Publications

correlations between carbon metabolism and virulence in bacteria.	bacteria have developed several mechanisms which allow the preferred utilization of the most efficiently metabolizable carbohydrates when these organisms are exposed to a mixture of carbon sources. interestingly, the same or similar mechanisms are used by some pathogens to control various steps of their infection process. the efficient metabolism of a carbon source might serve as signal for proper fitness. alternatively, the presence of a specific carbon source might indicate to bacterial cells ...	2009	19494580
membrane-protein structure: piercing insights.		2009	19494904
lac repressor is an antivirulence factor of salmonella enterica: its role in the evolution of virulence in salmonella.	the genus salmonella includes many pathogens of great medical and veterinary importance. bacteria belonging to this genus are very closely related to those belonging to the genus escherichia. laczya operon and laci are present in escherichia coli, but not in salmonella enterica. it has been proposed that salmonella has lost laczya operon and laci during evolution. in this study, we have investigated the physiological and evolutionary significance of the absence of laci in salmonella enterica. us ...	2009	19495420
mapping markers linked to porcine salmonellosis susceptibility.	the goal of this study was to identify pig chromosomal regions associated with susceptibility to salmonellosis. genomic dna from pig reference populations with differences in susceptibility to salmonella enterica serovar choleraesuis as quantified by spleen and liver bacterial colonization at day 7 post-infection (dpi; van diemen et al. 2002) was used. these samples belonged to the offspring of a sire thought to be heterozygous for genes involved in susceptibility to salmonellosis. amplified fra ...	2009	19496771
slc11a1 limits intracellular growth of salmonella enterica sv. typhimurium by promoting macrophage immune effector functions and impairing bacterial iron acquisition.	the natural resistance-associated macrophage protein 1, slc11a1, is a phagolysosomal transporter for protons and divalent ions including iron that confers host protection against diverse intracellular pathogens including salmonella. we investigated and compared the regulation of iron homeostasis and immune function in raw264.7 murine phagocytes stably transfected with non-functional slc11a1 and functional slc11a1 controls in response to an infection with salmonella enterica serovar typhimurium. ...	2009	19500110
stress-induced prophage dna replication in salmonella enterica serovar typhimurium.	salmonella typhimurium, a foodborne pathogen, is the cause of new outbreaks every year. the virulence of new pathogens is determined by their virulence genes, many of them carried on transferable elements, such as prophages. in bacteria harboring multiple prophages such as salmonella, the reassortment of these genes plays a major role in the emergence of new pathogens and consequently new epidemics. this gene transfer depends on prophage induction and the initiation of the phage lytic cycle. in ...	2009	19501196
escherichia coli o123 o antigen genes and polysaccharide structure are conserved in some salmonella enterica serogroups.	the serotyping of o and h antigens is an important first step in the characterization of salmonella enterica. however, serotyping has become increasingly technically demanding and expensive to perform. we have therefore sequenced additional s. enterica o antigen gene clusters to provide information for the development of dna-based serotyping methods. three s. enterica isolates had o antigen gene clusters with homology to the escherichia coli o123 o antigen region. o antigen clusters from two ser ...	2009	19502376
macrophage-specific overexpression of antimicrobial peptide pr-39 inhibits intracellular growth of salmonella enterica serovar typhimurium in macrophage cells.	although purified and synthesised pr-39 shows potent antibacterial effects in vitro, its ability to kill intracellular bacteria in macrophages, which are a major cause of refractory intracellular infection, has not yet been demonstrated. both to enhance its antimicrobial potential and to reduce systemic side effects, it would be desirable to deliver pr-39 into macrophage cells and to limit its activation to the site of infection. to address this issue, pr-39 dna was inserted into the eukaryotic ...	2009	19505806
mesenteric lymph nodes confine dendritic cell-mediated dissemination of salmonella enterica serovar typhimurium and limit systemic disease in mice.	in humans with typhoid fever or in mouse strains susceptible to salmonella enterica serovar typhimurium (s. typhimurium) infection, bacteria gain access to extraintestinal tissues, causing severe systemic disease. here we show that in the gut-draining mesenteric lymph nodes (mln), the majority of s. typhimurium-carrying cells show dendritic-cell (dc) morphology and express the dc marker cd11c, indicating that s. typhimurium bacteria are transported to the mln by migratory dcs. in vivo flt-3l-ind ...	2009	19506012
h-ns modulates multidrug resistance of salmonella enterica serovar typhimurium by repressing multidrug efflux genes acref.	screening of salmonella mutants for the ability to increase beta-lactam resistance has led to the identification of a mutation in hns, which codes for the histone-like nucleoid structuring protein (h-ns). in this study, we report that h-ns modulates multidrug resistance through repression of the genes that encode the acref multidrug efflux pump in salmonella enterica serovar typhimurium.	2009	19506059
kinetic and functional analysis of l-threonine kinase, the pdux enzyme of salmonella enterica.	the pdux enzyme of salmonella enterica is an l-threonine kinase used for the de novo synthesis of coenzyme b(12) and the assimilation of cobyric acid. pdux with an n-terminal histidine tag (his(8)-pdux) was produced in escherichiacoli and purified. the recombinant enzyme was soluble and active. kinetic analysis indicated a steady-state ordered bi bi complex mechanism in which atp is the first substrate to bind. based on a multiple sequence alignment of pdux homologues and other ghmp (galactokina ...	2009	19509296
priming of salmonella enterica serovar typhi-specific cd8(+) t cells by suicide dendritic cell cross-presentation in humans.	the emergence of antibiotic-resistant strains of salmonella enterica serovar typhi (s. typhi), the etiologic agent of typhoid fever, has aggravated an already important public health problem and added new urgency to the development of more effective typhoid vaccines. to this end it is critical to better understand the induction of immunity to s. typhi. cd8(+) t cells are likely to play an important role in host defense against s. typhi by several effector mechanisms, including killing of infecte ...	2009	19517022
chlorine dioxide gas from an aqueous solution: reduction of salmonella in wounds on tomato fruit and movement to sinks in a treatment chamber.	chlorine dioxide (clo2) off-gassed from an aqueous solution and reacted incrementally with potassium iodide solutions (sinks). after 30 min, 45% of the initial dose was detected as chlorite ion in the sink, whereas 35% of the initial dose was still in the source. aqueous solutions of clo2 can be used as a source of clo2 gas in various laboratory experiments involving treatment of fruits or vegetables. movement from source to sink is continuous, which precludes the development of large headspace ...	2009	19517720
characterization of planktonic and biofilm communities of day-of-hatch chicks cecal microflora and their resistance to salmonella colonization.	recent concerns about the use of antimicrobials in food animals have increased interest in the microbial ecology and biofilms within their gastrointestinal tract. this work used a continuous-flow chemostat system to model the microbial community within the ceca from day-of-hatch chicks and its ability to resist colonization by salmonella enterica serovar typhimurium. we characterized the biofilm and planktonic communities from five cultures by using automated ribotyping. eight species from six d ...	2009	19517721
an outbreak of salmonella enterica serotype litchfield infection in australia linked to consumption of contaminated papaya.	an outbreak of 26 cases of salmonella litchfield infection occurred in the states of western australia and queensland between october 2006 and january 2007. a case-control study was conducted with 12 cases and 24 controls, and a significant association was found between illness and consumption of papaya (odds ratio, 32.8; 95% confidence interval, 2.71 to 883.5). papaya samples were collected from 26 stores in western australia, and 9 of 38 samples were contaminated with salmonella litchfield. th ...	2009	19517740
[characterisation of a phenotypic monophasic variant belonging to salmonella enterica subsp. enterica serovar typhimurium from wild birds and its possible transmission to cats and humans].	in the last two years the national salmonella reference laboratory (nrl-salm) received an accumulating number of salmonellae with sero-formula 4,12:-:1,2 isolated from perished wild birds, particularly siskins. within these strains flagellar antigen of the first phase was phenotypically not detectable. by pcr a fragment could be amplified coding specifically for the h:i-flagellar antigen. consequently, this is a phenotypically monophasic variant of salmonella enterica subsp. enterica serovar typ ...	2009	19517930
interaction of nalidixic acid and ciprofloxacin with wild type and mutated quinolone-resistance-determining region of dna gyrase a.	the quinolones exert their anti-bacterial activity by binding to dna gyrase a (gyra), an essential enzyme in maintenance of dna topology within bacterial cell. the mutations conferring resistance to quinolones arise within the quinolone-resistance-determining region (qrdr) of gyra. therefore, quinolones interaction with wild and mutated gyra can provide the molecular explanation for resistance. resistant strains of salmonella enterica of our hospital have shown mutations in the qrdr of gyra of s ...	2009	19517991
conservation and divergence among salmonella enterica subspecies.	genome sequencing efforts of taxonomically proximate organisms successfully divulged proteomic diversity embedded within closely related organisms. the salmonella enterica subspecies represents a group of enterobacteric pathogens known to share similar genomic content yet possess diverse host specificity and distinct disease symptoms. study of salmonella enterica subspecies proteomes reports an overestimation of the proximity among the subspecies. interestingly, orthology comparison among salmon ...	2009	19519479
novel role of the nitrite transporter nirc in salmonella pathogenesis: spi2-dependent suppression of inducible nitric oxide synthase in activated macrophages.	activation of macrophages by interferon gamma (ifn-gamma) and the subsequent production of nitric oxide (no) are critical for the host defence against salmonella enterica serovar typhimurium infection. we report here the inhibition of ifn-gamma-induced no production in raw264.7 macrophages infected with wild-type salmonella. this phenomenon was shown to be dependent on the nirc gene, which encodes a potential nitrite transporter. we observed a higher no output from ifn-gamma-treated macrophages ...	2009	19520723
dna microarray for molecular epidemiology of salmonella.	salmonellosis is a common infection estimated to affect 3 billion people and to cause 200,000 deaths every year. infections can appear as enteric fever, gastroenteritis, bacteremia, or extraintestinal focal infection. the course of the disease depends on a variety of factors, including infective dose, immune status of the host, and the genetic background of both the host and the pathogen. it has been recognized that certain salmonella types play a major role in the epidemiology of salmonella. he ...	2009	19521880
lactobacilli stimulate the innate immune response and modulate the tlr expression of ht29 intestinal epithelial cells in vitro.	the potentially probiotic strain lactobacillus plantarum bfe 1685 isolated from a child's faeces and the probiotic strain lactobacillus rhamnosus gg were investigated for their capability to influence the innate immune response of ht29 intestinal epithelial cells towards salmonella enterica serovar typhimurium. furthermore, their capacity to modulate toll-like receptor expression of ht29 cells was investigated at the mrna and protein levels. tnf-alpha was used in cell culture with ht29 cells to ...	2009	19523707
a comparison of two pcr-based typing methods with pulsed-field gel electrophoresis in salmonella enterica serovar enteritidis.	two novel molecular typing methods, multiple-locus variable-number tandem repeats (vntr) analysis (mlva) and multiple amplification of phage loci typing (maplt), were compared with pulsed-field gel electrophoresis (pfge) for the discrimination of 128 salmonella enterica serovar enteritidis (s. enteritidis) isolates. selected epidemiologically unrelated isolates represented a cross-section of phage types routinely isolated in australia and included 28 isolates that could not be assigned a phage t ...	2009	19217348
[evolutionary engineering in salmonella: emergence of hybrid virulence-resistance plasmids in non-typhoid serotypes].	an example of evolutive engineering in bacterial pathogens is the emergence of hybrid virulence-resistance (vr) plasmids in salmonella enterica, resulting from an association between antimicrobial resistance determinants and specific virulence plasmids of the s. typhimurium and s. choleraesuis serotypes. vr plasmids all possess the spv (salmonella plasmid virulence) operon, which is involved in systemic infection; however, they differ in the presence of other virulence determinants and in the re ...	2009	19218002
subspecies iiia and iiib salmonellae are defective for colonization of murine models of salmonellosis compared to salmonella enterica subsp. i serovar typhimurium.	non-subspecies i salmonellae are commensals of cold-blooded vertebrates and cause sporadic disease in mammals. the reasons why non-subspecies i salmonellae do not circulate in populations of warm-blooded vertebrates, but instead only cause occasional disease in this niche, are unknown. we examined the ability of salmonella enterica subsp. iiia (subsp. arizonae) and subsp. iiib (subsp. diarizonae) isolates to grow competitively with subspecies i (serovar typhimurium) atcc 14028 in vitro, to colon ...	2009	19218378
role of fimw, fimy, and fimz in regulating the expression of type i fimbriae in salmonella enterica serovar typhimurium.	type i fimbriae in salmonella enterica serovar typhimurium are surface appendages that facilitate binding to eukaryotic cells. expression of the fim gene cluster is known to be regulated by three proteins--fimw, fimy, and fimz--and a trna encoded by fimu. in this work, we investigated how these proteins and trna coordinately regulate fim gene expression. our results indicate that fimy and fimz independently activate the p(fima) promoter which controls the expression of the fim structural genes. ...	2009	19218381
regulation of igaa and the rcs system by the mvia response regulator in salmonella enterica.	igaa is a membrane protein that prevents overactivation of the rcs regulatory system in enteric bacteria. here we provide evidence that igaa is the first gene in a sigma(70)-dependent operon of salmonella enterica serovar typhimurium that also includes yrfg, yrfh, and yrfi. we also show that the lon protease and the mvia response regulator participate in regulation of the igaa operon. our results indicate that mvia regulates igaa transcription in an rpos-dependent manner, but the results also su ...	2009	19218385
antimicrobial susceptibility profiles of salmonella enterica serotypes recovered from pens of commercial feedlot cattle using different types of composite samples.	salmonella enterica in cattle production systems may be associated with important human and animal disease issues. however, tremendous diversity exists among salmonella recovered, and more information is needed about strains of greatest potential health concern, particularly those that are multidrug resistant (mdr). by characterizing salmonella isolates from commercial feedlot pens, this study aimed to evaluate the strain diversity and prevalence of mdr salmonella from different types of composi ...	2009	19219500
global regulators and environmental adaptation in gram-negative pathogens.	a powerful combination of single-gene studies and whole genome approaches has provided a wealth of information about the regulatory circuits used by bacteria to adapt to the environmental changes that are encountered during infection. the facultative intracellular pathogen salmonella enterica will be used to illustrate how global regulators such as the nucleoid-associated proteins fis and h-ns collaborate with fluctuations in the superhelicity of the dna template to modify the gene expression pr ...	2009	19220355
osmoregulated periplasmic glucans are needed for competitive growth and biofilm formation by salmonella enterica serovar typhimurium in leafy-green vegetable wash waters and colonization in mice.	osmoregulated periplasmic glucans (opgs) are major periplasmic constituents of gram-negative bacteria. the role of opgs has been postulated in symbiotic as well as pathogenic host-microorganism interactions. here, we report the role of opgs from salmonella enterica serovar typhimurium during growth and biofilm formation in leafy-green vegetable wash water. the opggh mutant strain, which was defective in opg biosynthesis, initiated the growth at a slower rate in wash waters obtained from spinach, ...	2009	19222578
development of non-antibiotic-resistant, chromosomally based, constitutive and inducible expression systems for aroa-attenuated salmonella enterica serovar typhimurium.	live-vaccine delivery systems expressing two model antigens from mycoplasma hyopneumoniae, f2(p97) (adh) and nrdf, were constructed using salmonella enterica serovar typhimurium aroa (stm-1), and immunogenicity in mice was evaluated. recombinant plasmid-based expression (pbe) and chromosomally based expression (cbe) systems were constructed. the pbe system was formed by cloning both antigen genes into pjla507 to create an operon downstream of temperature-inducible promoters. constitutive cbe was ...	2009	19223478
emergence of plasmid-mediated quinolone resistance among non-typhi salmonella enterica isolates from humans in the united states.	plasmid-mediated quinolone resistance determinants are emerging among gram-negative pathogens. here we report results of a retrospective study investigating the prevalence of aac(6')-ib-cr, qepa, and qnr genes among 19,010 human isolates of non-typhi salmonella enterica collected in the united states from 1996 to 2006.	2009	19223618
screening and characterization of monoclonal antibodies to the surface antigens of listeria monocytogenes serotype 4b.	this study aims to develop and characterize monoclonal antibodies (mabs) with high specificity and affinity for surface antigens of an epidemiologically important serotype 4b of listeria monocytogenes.	2009	19226395
coordinated regulation of virulence during systemic infection of salmonella enterica serovar typhimurium.	to cause a systemic infection, salmonella must respond to many environmental cues during mouse infection and express specific subsets of genes in a temporal and spatial manner, but the regulatory pathways are poorly established. to unravel how micro-environmental signals are processed and integrated into coordinated action, we constructed in-frame non-polar deletions of 83 regulators inferred to play a role in salmonella enteriditis typhimurium (stm) virulence and tested them in three virulence ...	2009	19229334
salmonella paratyphi c: genetic divergence from salmonella choleraesuis and pathogenic convergence with salmonella typhi.	background: although over 1400 salmonella serovars cause usually self-limited gastroenteritis in humans, a few, e.g., salmonella typhi and s. paratyphi c, cause typhoid, a potentially fatal systemic infection. it is not known whether the typhoid agents have evolved from a common ancestor (by divergent processes) or acquired similar pathogenic traits independently (by convergent processes). comparison of different typhoid agents with non-typhoidal salmonella lineages will provide excellent models ...	2009	19229335
genome-wide analysis of the prea/preb (qseb/qsec) regulon of salmonella enterica serovar typhimurium.	the salmonella prea/preb two-component system (tcs) is an ortholog of the qsebc tcs of escherichia coli. in both salmonella and e. coli, this system has been shown to affect motility and virulence in response to quorum-sensing and hormonal signals, and to affect the transcription of the salmonella enterica serovar typhimurium (s. typhimurium) pmrab operon, which encodes an important virulence-associated tcs.	2009	19236707
risk factors for salmonella enterica subsp. enterica contamination in 519 french laying hen flocks at the end of the laying period.	a cross-sectional study was carried out to identify risk factors for salmonella spp. contamination in french laying hen flocks at the end of the laying period. five hundred and nineteen flocks were studied between october 2004 and september 2005. the salmonella status of the flocks was assessed from 5 faeces samples (pooled faeces samples from cage flocks and foot swabs from flocks kept on the floor, i.e. in a barn, outdoors and on organic farms) and 2 dust samples analysed using a classical bac ...	2009	19237216
contribution of flagellin pattern recognition to intestinal inflammation during salmonella enterica serotype typhimurium infection.	salmonella enterica serotype typhimurium causes acute inflammatory diarrhea in humans. flagella contribute to intestinal inflammation, but the mechanism remains unclear since most mutations abrogating pattern recognition of flagellin also prevent motility and reduce bacterial invasion. to determine the contribution of flagellin pattern recognition to the generation of innate immune responses, we compared in two animal models a nonmotile, but flagellin-expressing and -secreting serotype typhimuri ...	2009	19237529
interactions of salmonella enterica with lettuce leaves.	to investigate the interactions of salmonella enterica with abiotic and plant surfaces and their effect on the tolerance of the pathogen to various stressors.	2009	19239550
integron-mediated multidrug resistance in a global collection of nontyphoidal salmonella enterica isolates.	salmonella enterica bacteria have become increasingly resistant to antimicrobial agents, partly as a result of genes carried on integrons. clonal expansion and horizontal gene transfer may contribute to the spread of antimicrobial drug-resistance integrons in these organisms. we investigated this resistance and integron carriage among 90 isolates with the acssut phenotype (resistance to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline) in a global collection of s. en ...	2009	19239750
control of foodborne pathogens and soft-rot bacteria on bell pepper by three strains of bacterial antagonists.	forty-two representative strains of native bacteria associated with fresh peeled baby carrots were isolated and characterized. two of these strains, identified as pseudomonas fluorescens ag3a (pf ag3a) and bacillus yd1, were evaluated in conjunction with another known antagonist, p. fluorescens 2-79 (pf 2-79), for their potential as biocontrol agents of human pathogens (listeria monocytogenes, yersinia enterocolitica, salmonella enterica, and escherichia coli o157:h7) and soft-rot bacteria (erwi ...	2009	19205468
a method for investigating protein-protein interactions related to salmonella typhimurium pathogenesis.	we successfully modified an existing method to investigate protein-protein interactions in the pathogenic bacterium salmonella enterica serovar typhimurium (salmonella typhimurium). this method includes (i) addition of a histidine-biotin-histidine tag to the bait proteins via recombinant dna techniques, (ii) in vivo cross-linking with formaldehyde, (iii) tandem affinity purification of bait proteins under fully denaturing conditions, and (iv) identification of the proteins cross-linked to the ba ...	2009	19206470
pathogen trafficking pathways and host phosphoinositide metabolism.	phosphoinositide (pi) glycerolipids are key regulators of eukaryotic signal transduction, cytoskeleton architecture and membrane dynamics. the host cell pi metabolism is targeted by intracellular bacterial pathogens, which evolved intricate strategies to modulate uptake processes and vesicle trafficking pathways. upon entering eukaryotic host cells, pathogenic bacteria replicate in distinct vacuoles or in the host cytoplasm. vacuolar pathogens manipulate pi levels to mimic or modify membranes of ...	2009	19208094
hydrophobic peptides: novel regulators within bacterial membrane.	identification of short coding sequences is challenging, both experimentally and in silico, and functional natural peptides (< 50 amino acids) have to a large extent been overlooked in gram-negative bacteria. recent results have converged to highlight the role of hydrophobic peptides that form a novel class of active molecules in escherichia coli and salmonella enterica serovar typhimurium. these peptides can play a regulatory role by interacting with protein partners at the inner membrane and b ...	2009	19210615
sequence analysis of escherichia coli o157:h7 bacteriophage phiv10 and identification of a phage-encoded immunity protein that modifies the o157 antigen.	bacteriophage phiv10 is a temperate phage, which specifically infects escherichia coli o157:h7. the nucleotide sequence of the phiv10 genome is 39 104 bp long and contains 55 predicted genes. phiv10 is closely related to two previously sequenced phages, the salmonella enterica serovar anatum (group e1) phage epsilon15 and a prophage from e. coli apec o1. the attachment site of phiv10, like those of its two closest relatives, overlaps the 3' end of guaa in the host chromosome. phiv10 encodes an o ...	2009	19210675
antimicrobial properties of the equine alpha-defensin defa1 against bacterial horse pathogens.	defensins are small effector molecules of the innate immune system, synthesised by various organisms including plants and animals. the peptides act as endogenous antibiotics with an antimicrobial activity against a broad spectrum of microbes including bacteria, fungi and viruses. alpha-defensins are a subgroup of the defensin family, their synthesis is limited to some tissues and furthermore to some mammalian species including the horse. equine defa1 is an enteric alpha-defensin exclusively prod ...	2009	19211153
re-emerging chloramphenicol sensitivity and emerging low level ciprofloxacin resistance among salmonella enterica serotype typhi isolates in north india.	ciprofloxacin has become the antibiotic of choice for the treatment of typhoid fever with the emergence and worldwide spread of salmonella enterica typhi strains resistant to chloramphenicol. however, the rampant use of ciprofloxacin gradually led to an increase in its minimum inhibitory concentration against s. enterica typhi. this threatened its therapeutic efficacy and resulted in the re-emergence of chloramphenicol-sensitive s. enterica typhi strains.	2009	19211419
effect of a direct-fed microbial (primalac) on structure and ultrastructure of small intestine in turkey poults.	the effects of dietary supplementation of the direct-fed microbial (dfm) primalac in mash or crumbled feed on histological and ultrastructural changes of intestinal mucosa was determined in 2 populations of poults; 1 with and 1 without a salmonella spp. challenge. three hundred thirty-six 1-d-old female large white turkey poults were randomly distributed into 8 treatment groups with 6 replicates of 7 poults in each pen. the poults were placed on 1 of 4 dietary treatments in a 2 x 2 x 2 factorial ...	2009	19211517
prevalence and risk factors for bacterial food-borne zoonotic hazards in slaughter pigs: a review.	the hygiene package and regulation ec-2160/2003 require information flow from farm to slaughterhouse to enhance european consumers protection in a 'farm to fork' approach. this obligation especially concerns food-borne zoonotic hazards transmitted to humans through pork consumption, such as thermophilic campylobacter spp., listeria monocytogenes, salmonella enterica and yersinia enterocolitica. prevalence estimates of these four hazards are affected by the sampling strategy and diagnostic proced ...	2009	19175574
occurrence of extended-spectrum beta-lactamase-producing salmonella enterica in northern spain with evidence of ctx-m-9 clonal spread among animals and humans.	among the 1233 salmonella enterica isolates obtained in two spanish hospitals, five isolates (0.4%) (serovars: virchow, four; livingstone, one) had the phenotype of an extended-spectrum beta-lactamase (esbl) producer. the genetic characterization of the esbl of s. enterica livingstone revealed a bla(shv-2) gene. the bla(ctx-m-10) gene in a phage-related genetic environment was found in one s. enterica virchow isolate, and the bla(ctx-m-9) gene within the in60 integron was found in the three rema ...	2009	19175621
genetic stability of vaccine strain salmonella typhi ty21a over 25 years.	the attenuated live bacterial vaccine strain salmonella enterica serovar typhi ty21a is the main constituent of vivotif, the only licensed oral vaccine against typhoid fever. the strain was developed in the 1970s by chemical mutagenesis. in the course of this mutagenesis, a number of mutations were introduced into the vaccine strain. characterisation of the vaccine strain during development as well as release of master- and working seed lots (msl and wsl) and commercial batches is based on pheno ...	2009	19121604
calprotectin s100a9 calcium-binding loops i and ii are essential for keratinocyte resistance to bacterial invasion.	epithelial cells expressing calprotectin, a heterodimer of s100a8 and s100a9 proteins, are more resistant to bacterial invasion. to determine structural motifs that affect resistance to bacterial invasion, mutations were constructed in s100a9 targeting the calcium-binding loops i and ii (e36q, e78q, e36q,e78q) and the c terminus (s100a9(1-99) and s100a9(1-112)), which contains putative antimicrobial zinc-binding and phosphorylation sites. the s100a8 and mutated s100a9 encoding plasmids were tran ...	2009	19122197
typhoid rhabdomyolysis with acute renal failure and acute pancreatitis: a case report and review of the literature.	we report a case of typhoid rhabdomyolysis with acute renal failure and acute pancreatitis in a 23-year-old vietnamese male who was admitted to the intensive care unit with a 15-day history of fever followed by severe abdominal pain. on examination, the patient was febrile and his abdomen was diffusely tender. serum creatinine was 533 micromol/l, pancreatic amylase 1800 u/l and lipase 900 u/l; the myoglobin blood level was high, which is associated with significant myoglobinuria. blood, urine an ...	2009	19147385
paracoccidioides brasiliensis vaccine formulations based on the gp43-derived p10 sequence and the salmonella enterica flic flagellin.	paracoccidioidomycosis (pcm) is a systemic granulomatous disease caused by the dimorphic fungus paracoccidioides brasiliensis. anti-pcm vaccine formulations based on the secreted fungal cell wall protein (gp43) or the derived p10 sequence containing a cd4(+) t-cell-specific epitope have shown promising results. in the present study, we evaluated new anti-pcm vaccine formulations based on the intranasal administration of p. brasiliensis gp43 or the p10 peptide in combination with the salmonella e ...	2009	19204092
rapid, sensitive, and specific detection of the o4 group of salmonella enterica by loop-mediated isothermal amplification.	the present study developed a loop-mediated isothermal amplification (lamp) assay that amplifies the fragments of o4 salmonella enterica-specific gene rfbj and evaluates the potential use in detection of salmonella enterica serovar typhimurium (st). the detection limit of the lamp assay was 10(3) cfu/ml, which was lower than that of the pcr assay with the same target gene (10(5) cfu/ml), confirmed by electrophoresis. the increased turbidity of the final products of lamp was also observed with mo ...	2009	19630227
emergence of fluoroquinolone-resistant strains of salmonella enterica in surabaya, indonesia.	typhoid fever remains a major health problem in developing countries. fluoroquinolones such as ciprofloxacin emerged as the 1st-choice treatment of enteric fever, including typhoid, in the 1990s. recently, salmonella typhi strains with resistance to ciprofloxacin have been increasingly reported in several countries, although the fluoroquinolone-resistant clinical strain has not been reported in indonesia. in the present study, we examined the drug susceptibility and the presence of gyra mutation ...	2009	19631095
rapid identification of salmonella enterica subsp. arizonae and s. enterica subsp. diarizonae by real-time polymerase chain reaction.	reptiles are popular as pets, leading to an increased risk of human infections due to uncommon salmonella strains including the arizona group (subspecies arizonae and diarizonae). we present a real-time arizona-specific polymerase chain reaction demonstrating 100% specificity and 99.6% sensitivity, offering savings in time and labor over traditional identification methods.	2009	19631101
innate immune gene expression differentiates the early avian intestinal response between salmonella and campylobacter.	salmonella enterica serovar typhimurium and campylobacter jejuni are major human pathogens, yet colonise chickens without causing pathology. the aim of this study was to compare intestinal innate immune responses to both bacterial species, in a 4-week-old broiler chicken model. challenged and control birds were sacrificed and tissue samples taken for histopathology and rna extraction. no significant clinical or pathological changes were observed in response to infection with either bacterial spe ...	2009	19632728
distribution of sulfonamide resistance genes in escherichia coli and salmonella isolates from swine and chickens at abattoirs in ontario and québec, canada.	sulfonamide-resistant escherichia coli and salmonella isolates from pigs and chickens in ontario and québec were screened for sul1, sul2, and sul3 by pcr. each sul gene was distributed differently across populations, with a significant difference between distribution in commensal e. coli and salmonella isolates and sul3 restricted mainly to porcine e. coli isolates.	2009	19633109
[a new method of designing genechip probe for frontier port detection of pathogenic microorganism].	in the process of designing genechip probe for detecting pathogenic microorganism, the selection of single nucleotide polymorphism (snp) combination is of great importance. at present, there is no automatic design method. this work is hard and the result is not always well. a new approach for selecting snp combination is presented in this paper. genetic algorithm is used to search optimal solution on the basis of classification ability of snp combination, which is evaluated by the rough set theo ...	2009	19634689
development and application of an electrochemical plate coupled with immunomagnetic beads (elime) array for salmonella enterica detection in meat samples.	salmonella is one of the main organisms causing outbreaks of foodborne illness, and meat is one of the major vehicles of salmonellosis throughout the world. a novel analytical immunosensor array, based on a 96-well electrochemical plate coupled with immunomagnetic beads (elime array), is proposed for the detection of salmonella in meat samples. after an optimization study, using salmonella enterica serotype enteritidis as reference antigen, the ability of the method to interact with a large numb ...	2009	19639993
survival and growth of salmonella and vibrio in som-fak, a thai low-salt garlic containing fermented fish product.	fermentation of raw fish is a common process in asia for improvement of shelf life and safety, however, little is known about the survival of pathogenic bacteria in these products. raw fish may be contaminated with salmonella and vibrio species. the purpose of this study was to determine survival and potential growth of salmonella enterica serovar weltevreden, s. enterica serovar enteritidis, vibrio cholerae and v. parahaemolyticus as influenced by the preservation parameters (sodium chloride, g ...	2009	19640599
detection of enterobacter sakazakii and other pathogens associated with infant formula powder by use of a dna microarray.	pathogen detection is critical to the process of generating and testing powdered infant formula (pif). an obstacle associated with pif microbial surveillance is that most current procedures are time-consuming and labor-intensive. we have developed a rapid, dna microarray-based detection technique to identify 10 different pathogenic bacteria associated with pif contamination based on the 16s-23s rrna gene internal transcribed spacer (its) sequences and wzy (o antigen polymerase) gene. using this ...	2009	19641057
gamma radiation used as hygienization technique for foods does not induce viable but non-culturable state (vbnc) in salmonella enterica subsp. enterica serovar typhimurium.	gamma radiation has been widely used for hygienization of food products. whether gamma radiation stress induces vbnc state in salmonella is of great concern. therefore, the study was carried out to determine whether gamma radiation exposure induces vbnc state in salmonella enterica subsp. enterica serovar typhimurium (s. typhimurium). the parameters tested were culturability on agar medium, transcriptional activity by rt-pcr, cytoplasmic membrane integrity, and direct viable count using live/dea ...	2009	19641961
salmonella enterica subclinical infection: bacteriological, serological, pulsed-field gel electrophoresis, and antimicrobial resistance profiles--longitudinal study in a three-site farrow-to-finish farm.	the aim of this surveillance was to study both salmonella spp. shedding patterns and the time course of serological response in farrow-to-finish reared pigs from a subclinically infected farm. antimicrobial resistance profile, molecular subtyping, and the relationship among the isolates were determined by pulsed-field gel electrophoresis (pfge). a farrow-to-finish farm of 6000 sows, with a history of salmonella typhimurium septicemia, was selected. a longitudinal bacteriological and serological ...	2009	19642916
transcriptional profiling avian beta-defensins in chicken oviduct epithelial cells before and after infection with salmonella enterica serovar enteritidis.	salmonella enterica serovar enteritidis (se) colonizes the ovary and oviduct of chickens without causing overt clinical signs which can lead to se-contamination of the content and membrane of shell-eggs as well as hatchery eggs. the organism utilizes the salmonella pathogenicity island-2 encoded type iii secretion system (t3ss-2) to promote persistence in the oviduct of laying hens. in this study, reverse transcriptase-polymerase chain reaction (rt-pcr) was carried out to determine the expressio ...	2009	19642979
internalization of salmonella enterica in leaves is induced by light and involves chemotaxis and penetration through open stomata.	outbreaks of salmonellosis related to consumption of fresh produce have raised interest in salmonella-plant interactions leading to plant colonization. incubation of gfp-tagged salmonella enterica with iceberg lettuce leaves in the light resulted in aggregation of bacteria near open stomata and invasion into the inner leaf tissue. in contrast, incubation in the dark resulted in a scattered attachment pattern and very poor stomatal internalization. forcing stomatal opening in the dark by fusicocc ...	2009	19648358
antimicrobial resistance-conferring plasmids with similarity to virulence plasmids from avian pathogenic escherichia coli strains in salmonella enterica serovar kentucky isolates from poultry.	salmonella enterica, a leading cause of food-borne gastroenteritis worldwide, may be found in any raw food of animal, vegetable, or fruit origin. salmonella serovars differ in distribution, virulence, and host specificity. salmonella enterica serovar kentucky, though often found in the food supply, is less commonly isolated from ill humans. the multidrug-resistant isolate s. kentucky cvm29188, isolated from a chicken breast sample in 2003, contains three plasmids (146,811 bp, 101,461 bp, and 46, ...	2009	19648374
comprehensive identification of salmonella enterica serovar typhimurium genes required for infection of balb/c mice.	genes required for infection of mice by salmonella typhimurium can be identified by the interrogation of random transposon mutant libraries for mutants that cannot survive in vivo. inactivation of such genes produces attenuated s. typhimurium strains that have potential for use as live attenuated vaccines. a quantitative screen, transposon mediated differential hybridisation (tmdh), has been developed that identifies those members of a large library of transposon mutants that are attenuated. tmd ...	2009	19649318
purification, crystallization and preliminary x-ray analysis of flit, a bacterial flagellar substrate-specific export chaperone.	the assembly process of the bacterial flagellum is coupled to flagellar gene expression. flit acts not only as a flagellar type iii substrate-specific export chaperone for the filament-capping protein flid but also as a negative regulator that suppresses flagellar gene expression through its specific interaction with the master regulator flhd(4)c(2) complex. in this study, flit of salmonella enterica serovar typhimurium was expressed, purified and crystallized. crystals of semet flit were obtain ...	2009	19652350
cell yields and fermentation responses of a salmonella typhimurium poultry isolate at different dilution rates in an anaerobic steady state continuous culture.	the objectives of these studies were to determine cell yield and fermentation responses of a salmonella enterica serovar typhimurium poultry isolate using various dilution rates in steady state continuous culture incubations. s. enterica typhimurium cells were propagated in continuous cultures with a total volume of 0.50 l of luria bertani medium containing 0.1% glucose. dilution rates from 0.0125 to 1.44/h were used. cell protein concentration generally increased linearly with increased dilutio ...	2009	19655268
molecular typing of escherichia coli strains isolated from food in casablanca (morocco).	serotyping of o- and h- antigens is regarded as the gold standard in classification of e. coli for taxonomic and epidemiological purposes similar to the kaufmann-white scheme for salmonella enterica. molecular methods to replace or to support the serotyping were recently applied. using the molecular polymorphism of the somatic (o- antigen) gene rfb cluster and flagella (h- antigen) gene flic, 74 e. coli strains carrying the virulent genes isolated from food were characterised by polymerase chain ...	2009	19656466
protection of salmonella by ampicillin-resistant escherichia coli in the presence of otherwise lethal drug concentrations.	microbial systems have become the preferred testing grounds for experimental work on the evolution of traits that benefit other group members. this work, based on conceptual and theoretical models of frequency-dependent selection within populations, has proven fruitful in terms of understanding the dynamics of group beneficial or 'public goods' traits within species. here, we expand the scope of microbial work on the evolution of group-beneficial traits to the case of multi-species communities, ...	2009	19656787
global transcriptional response of salmonella enterica serovar typhi to anti-z66 antiserum.	recent studies have shown that flagella may modulate physiological processes by sensing environmental changes in temperature and moisture. when the z66(+) strain of salmonella enterica serovar typhi (s. typhi) was exposed to an antiserum against the z66 flagellar antigen, the fljba operon was deleted from a linear plasmid, leading to the unidirectional flagellar phase variation from fljb to flic. we hypothesized that flagella may serve as a sensor that responded to the antiserum by altering gene ...	2009	19659726
outbreak of salmonella enterica serotype muenster infections associated with goat's cheese, france, march 2008.	salmonella enterica serotype muenster (hereafter referred to as s. muenster) is rare in france and in europe. in france, a nationwide outbreak of gastrointestinal illness due to s. muenster occurred during march and april 2008. twenty-five laboratory-confirmed cases of s. muenster were documented by telephone using a trawling questionnaire. four patients were admitted to hospital and no death was recorded. among the 21 interviewed cases, 16 reported consumption of goat's cheese in the days prior ...	2009	19660242
macrophages influence salmonella host-specificity in vivo.	the generalist salmonella enterica serovar typhimurium causes disease in many animal species, but the closely related host-specific serovar typhi only causes disease in humans. typhi and typhimurium share major virulence loci; hence it is not known exactly why typhi does not cause disease in mice. we tested the hypothesis that macrophages contribute to salmonella host-specificity in mice. no significant difference in survival of the two serovars was observed in vitro in mouse macrophage cell lin ...	2009	19660538
[activity of ertapenem and ceftriaxone in the eradication of salmonella in a model of experimental peritonitis in mice].	since the beginning of the 1990s, the prevalence of isolates of non-typhoidal salmonella species resistant to antimicrobial agents, including those commonly used for the treatment of salmonella infections such as fluoroquinolones, trimethoprim-sulfamethoxazole or beta-lactams, has increased substantially. infections caused by multidrug-resistant strains of non-typhoidal salmonella are now frequently encountered. in order to consider an appropriate role of ertapenem in salmonella-due intraabdomin ...	2009	19662546
characterization of lactobacillus spp. isolated from the feces of breast-feeding piglets.	lactobacillus spp., referred to as ij-1 and ij-2, were isolated from the feces of breast-feeding piglets and analyzed for probiotic properties. according to the analyses of 16s rdna sequence, lactobacillus sp. ij-1 showed greater than 99% homology with lactobacillus reuteri dsm 20016(t), and lactobacillus sp. ij-2 had greater than 99% homology with the l. gasseri atcc 33323(t) and l. johnsonii atcc 33200(t). the ph changes in the culture media of lactobacillus sp. ij-1 and lactobacillus sp. ij-2 ...	2009	19664551
autonomous and flik-dependent length control of the flagellar rod in salmonella enterica.	salmonella flgg point mutations produce filamentous rod structures whose lengths are determined by flik. flik length variants produce rods with lengths proportional to the corresponding flik molecular size, suggesting that flik controls the length of not only the hook but also the rod by the same molecular mechanism.	2009	19666714
quantification of horizontal transmission of salmonella enterica serovar enteritidis bacteria in pair-housed groups of laying hens.	an important source of human salmonellosis is the consumption of table eggs contaminated with salmonella enterica serovar enteritidis. optimization of the various surveillance programs currently implemented to reduce human exposure requires knowledge of the dynamics of s. enteritidis infection within flocks. the aim of this study was to provide parameter estimates for a transmission model of s. enteritidis in laying-type chicken flocks. an experiment was carried out with 60 pairs of laying hens. ...	2009	19666725
autophagy genes protect against salmonella typhimurium infection and mediate insulin signaling-regulated pathogen resistance.	a conserved insulin-like pathway modulates both aging and pathogen resistance in caenorhabditis elegans. however, the specific innate effector functions that mediate this pathogen resistance are largely unknown. autophagy, a lysosomal degradation pathway, plays a role in controlling intracellular bacterial pathogen infections in cultured cells, but less is known about its role at the organismal level. we examined the effects of autophagy gene inactivation on salmonella enterica serovar typhimuri ...	2009	19667176
silica-antibiotic hybrid nanoparticles for targeting intracellular pathogens.	we investigated the capability of biodegradable silica xerogel as a novel carrier of antibiotic and the efficacy of treatment compared to that with the same dose of free drug against murine salmonellosis. the drug molecules (31%) entrapped in the sol-gel matrix remained in biologically active form, and the bactericidal effect was retained upon drug release. the in vitro drug release profiles of the gentamicin from the xerogel and that from the xerogel-polyethylene glycol (peg) were distinctly di ...	2009	19667284
polysaccharides derived from yamoa (funtumia elastica) prime gammadelta t cells in vitro and enhance innate immune responses in vivo.	yamoa (ground bark of funtumia elastica tree) is marketed and sold as a dietary supplement with anecdotal therapeutic effects in the treatment of asthma and hay fever. we determined that yamoa and yamoa-derived polysaccharides affected innate immunity, in part, by priming gammadelta t cells. gene expression patterns in purified bovine gammadelta t cells and monocytes induced by yamoa were similar to those induced by ultrapure lipopolysaccharide (ulps). in the presence of accessory cells, yamoa h ...	2009	19671448
an improved method to knock out the asd gene of salmonella enterica serovar pullorum.	an asd-deleted (deltaasd) mutant of salmonella enterica serovar pullorum (sp) was constructed using an improved method of gene knockout by combining the pi-suicide plasmid system with the red disruption system. the asd gene was efficiently knocked out by the recombinant suicide vector, which replaced the asd gene with the cmr gene. based on the balanced lethal host-vector system, the phenotype of the deltaasd mutant was further defined. the improved method was simpler and more effective than pre ...	2009	19672470
use of stabilized luciferase-expressing plasmids to examine in vivo-induced promoters in the vibrio cholerae vaccine strain cvd 103-hgr.	live, attenuated vibrio cholerae vaccines can induce potent immune responses after only a single oral dose. the strategy of harnessing these strains to present antigens from heterologous pathogens to the mucosal immune system shows great promise. to fully realize this possibility, v. cholerae strains must be created that stably express antigens in vivo in sufficient quantity to generate an immune response. in vivo-induced promoters have been shown to increase the stability and immunogenicity of ...	2009	19678844
escherichia coli unsaturated fatty acid synthesis: complex transcription of the faba gene and in vivo identification of the essential reaction catalyzed by fabb.	although the unsaturated fatty acid (ufa) synthetic pathway of escherichia coli is the prototype of such pathways, several unresolved issues have accumulated over the years. the key players are the faba and fabb genes. earlier studies of faba transcription showed that the gene was transcribed from two promoters, with one being positively regulated by the fadr protein. the other weaker promoter (which could not be mapped with the technology then available) was considered constitutive because its ...	2009	19679654
antibody selection for immobilizing living bacteria.	we report a comparative study of the efficacy of immobilizing living bacteria by means of seven antibodies against bacterial surface antigens associated with salmonella enterica serovar typhimurium. the targeted bacterial antigens were cfa/i fimbriae, flagella, lipopolysaccharides (lps), and capsular f1 antigen. the best immobilization of s. typhimurium was achieved with the antibody against cfa/i fimbriae. the immobilization of bacteria using antiflagellin showed significant enhancement if the ...	2009	19681578
genomic diversity of citrate fermentation in klebsiella pneumoniae.	it has long been recognized that klebsiella pneumoniae can grow anaerobically on citrate. genes responsible for citrate fermentation of k. pneumoniae were known to be located in a 13-kb gene cluster on the chromosome. by whole genome comparison of the available k. pneumoniae sequences (mgh 78578, 342, and ntuh-k2044), however, we discovered that the fermentation gene cluster was present in mgh 78578 and 342, but absent in ntuh-k2044. in the present study, the previously unknown genome diversity ...	2009	19682387
role of a conserved prolyl residue (pro173) of mota in the mechanochemical reaction cycle of the proton-driven flagellar motor of salmonella.	the mota/b complex acts as the stator of the proton-driven bacterial flagellar motor. proton translocation through the stator complex is efficiently coupled with torque generation by the stator-rotor interactions. in salmonella enterica serovar typhimurium, the highly conserved pro173 residue of mota is close to the absolutely conserved asp33 residue of motb, which is believed to be a proton-binding site. pro173 is postulated to be involved in coupling proton influx to torque generation. however ...	2009	19683537
the s. typhimurium effector sope induces caspase-1 activation in stromal cells to initiate gut inflammation.	in the healthy intestinal mucosa, homeostasis between the immune system and commensal microflora prevents detrimental inflammatory responses. infection with acute enteropathogens such as salmonella enterica serovar typhimurium disturbs this homeostasis and triggers inflammation, but the underlying mechanisms are poorly understood. we found that bacterial delivery or ectopic expression of the s. typhimurium type iii effector protein sope, a known activator of host cellular rho gtpases, led to pro ...	2009	19683679
prognostic factors and clinical features of non-typhoid salmonella bacteremia in adults.	infections caused by non-typhoid salmonella (nts) have increased, and the increasing incidence of multidrug-resistant nts bacteremia in adult patients has also been noted. this study aimed to investigate the clinical and microbiological characteristics of nts bacteremia.	2009	19686996
molecular insights into farm animal and zoonotic salmonella infections.	salmonella enterica is a facultative intracellular pathogen of worldwide importance. infections may present in a variety of ways, from asymptomatic colonization to inflammatory diarrhoea or typhoid fever depending on serovar- and host-specific factors. human diarrhoeal infections are frequently acquired via the food chain and farm environment by virtue of the ability of selected non-typhoidal serovars to colonize the intestines of food-producing animals and contaminate the avian reproductive tra ...	2009	19687040
pspa family fusion proteins delivered by attenuated salmonella enterica serovar typhimurium extend and enhance protection against streptococcus pneumoniae.	pneumococcal surface protein a (pspa) is highly immunogenic and can induce a protective immune response against pneumococcal infection. pspa is divided into two major families based on serological variability: family 1 and family 2. to provide broad protection, pspa proteins from pneumococcal strains rx1 (family 1) and ef5668 (family 2) were combined to form two pspa fusion proteins, pspa/rx1-ef5668 and pspa/ef5668-rx1. each protein was fused to a type ii secretion signal and delivered by a reco ...	2009	19687204
msbb deletion confers acute sensitivity to co2 in salmonella enterica serovar typhimurium that can be suppressed by a loss-of-function mutation in zwf.	pathogens tolerate stress conditions that include low ph, oxidative stress, high salt and high temperature in order to survive inside and outside their hosts. lipopolysaccharide (lps), which forms the outer-leaflet of the outer membrane in gram-negative bacteria, acts as a permeability barrier. the lipid a moiety of lps anchors it to the outer membrane bilayer. the msbb enzyme myristoylates the lipid a precursor and loss of this enzyme, in salmonella, is correlated with reduced virulence and sev ...	2009	19689794
salmonella type iii secretion effector slrp is an e3 ubiquitin ligase for mammalian thioredoxin.	salmonella enterica encodes two virulence-related type iii secretion systems in salmonella pathogenicity islands 1 and 2, respectively. these systems mediate the translocation of protein effectors into the eukaryotic host cell, where they alter cell signaling and manipulate host cell functions. however, the precise role of most effectors remains unknown. using a genetic screen, we identified the small, reduction/oxidation-regulatory protein thioredoxin as a mammalian binding partner of the salmo ...	2009	19690162
interaction between host cells and septicemic salmonella enterica serovar typhimurium isolates from pigs.	salmonella enterica serovar typhimurium is an important pathogen in swine and is also a frequently reported zoonotic agent. the objective of this study was to characterize isolates of s. enterica serovar typhimurium associated with septicemia in swine and to compare them to isolates recovered from clinically healthy pigs. we were particularly interested in comparing the two groups of isolates for their ability to adhere to and invade host cells, to be phagocytized and survive in monocyte cells, ...	2009	19710281
kinetics of the natural, humoral immune response to salmonella enterica serovar typhi in kathmandu, nepal.	typhoid fever is a major public health problem in developing countries, conservatively estimated to occur in 17 million cases and be responsible for 200,000 deaths annually. we investigated the acquisition of natural immunity to salmonella enterica serovar typhi in a region where typhoid is endemic by testing sera from an age-stratified sample of 210 healthy participants in kathmandu, nepal, for bactericidal activity toward s. typhi and for anti-vi capsular polysaccharide antibodies. bactericida ...	2009	19710294
effect of mixed antimicrobial agents and flavors in active packaging films.	active packaging is an emerging food technology to improve the quality and safety of food products. many works have been developed to study the antimicrobial activity of essential oils. essential oils have been traditionally used as flavorings in food, so they have an important odor impact but they have as well antimicrobial properties that could be used to protect the food. recent developments in antimicrobial active packaging showed the efficiency of essential oils versus bread and bakery prod ...	2009	19711918
previously uncharacterized salmonella enterica genes required for swarming play a role in seedling colonization.	incidences of bacterial foodborne illness caused by ingestion of fresh produce are rising. instead of this being due to incidental contamination, the animal pathogen salmonella enterica utilizes specific molecular mechanisms to attach to and colonize plants. this work characterizes two s. enterica genes of unknown function: a putative periplasmic protein, stm0278, and a putative protein with a hydrolase in the c-terminus, stm0650. stm0278 and stm0650 are important for seedling colonization but a ...	2009	19713240
salmonella enterica serovar typhimurium exploits toll-like receptor signaling during the host-pathogen interaction.	salmonella survives and replicates in host cells by using a type iii secretion system to evade host immune defenses. the innate immune system plays an important role as a first line of defense against pathogens and is mediated in part by toll-like receptors (tlrs); however, the infection dynamics of salmonella enterica serovar typhimurium within macrophages stimulated with tlr ligands is poorly understood. we studied the infection dynamics of salmonella in murine macrophages previously exposed t ...	2009	19720755
perceptions, practices, and consequences associated with foodborne pathogens and the feeding of raw meat to dogs.	this study explored the impact of feeding raw meat to dogs on the fecal prevalence of several enteric bacterial zoonotic pathogens. campylobacter jejuni was isolated from 1/42 (2.6%) raw meat-fed dogs. salmonella enterica was isolated from 2/40 (5%) of the raw meat feeds, 6/42 (14%) raw meat-fed dog feces, none of the dogs that did not receive raw meat (p = 0.001), 4/38 (10.5%) of the vacuum cleaner waste samples from households where raw meat was fed, and 2/44 (4.5%) of vacuum cleaner waste sam ...	2009	19721784