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fimy does not interfere with fimz-fimw interaction during type 1 fimbria production by salmonella enterica serovar typhimurium.the production of type 1 fimbriae in salmonella enterica serovar typhimurium is controlled, in part, by three proteins, fimz, fimy, and fimw. amino acid sequence analysis indicates that fimz belongs to the family of bacterial response regulators of two-component systems. in these studies, we have demonstrated that introducing a mutation mimicking phosphorylation of fimz is necessary for activation of its target gene, fima. in addition, the interaction of fimz with fimw, a repressor of fima expre ...201324042120
a novel insight on signal transduction mechanism of rcscdb system in salmonella enterica serovar typhimurium.the rcscdb system of salmonella enterica serovar typhimurium is implicated in the control of capsule and flagella synthesis. the hybrid sensor rcsc, the phosphotransferase rcsd and the rcsb regulator, constitute the main components of the rcscdb system. the proposed rcs signaling cascade involves the autophosphorylation of rcsc and the transfer of the phosphate group to rcsb, mediated by rcsd. we previously reported that the overexpression of rcsb repress the transcription of rcsd by an autoregu ...201324023746
tetracycline accelerates the temporally-regulated invasion response in specific isolates of multidrug-resistant salmonella enterica serovar typhimurium.multidrug-resistant (mdr) salmonella isolates are associated with increased morbidity compared to antibiotic-sensitive strains and are an important health and safety concern in both humans and animals. salmonella enterica serovar typhimurium is a prevalent cause of foodborne disease, and a considerable number of s. typhimurium isolates from humans and livestock are resistant to three or more antibiotics. the majority of these mdr s. typhimurium isolates are resistant to tetracycline, a commonly ...201324020473
hfq and arca are involved in the stationary phase-dependent activation of salmonella pathogenicity island 1 (spi1) under shaking culture conditions.in salmonella enterica serovar typhimurium, many genes encoded within salmonella pathogenicity island 1 (spi1) are required to induce intestinal/diarrheal disease. in this study, we compared the expression of four spi1 genes (hila, invf, prgh, and sipc) under shaking and standing culture conditions and found that the expression of these genes was highest during the transition from the exponential to stationary phase under shaking conditions. to identify regulators associated with the stationary ...201324018968
proof-of-concept study for successful inter-laboratory comparison of mlva results.multiple-locus variable-number of tandem repeats analysis (mlva) is widely used for typing of pathogens. methods such as mlva based on determining dna fragment size by the use of capillary electrophoresis have an inherent problem as a considerable offset between measured and real (sequenced) lengths is commonly observed. this discrepancy arises from variation within the laboratory set-up used for fragment analysis. to obtain comparable results between laboratories using different set-ups, some f ...201324008232
altered expression and localization of ion transporters contribute to diarrhea in mice with salmonella-induced enteritis.salmonella enterica serovar typhimurium is an enteropathogen that causes self-limiting diarrhea in healthy individuals, but poses a significant health threat to vulnerable populations. our understanding of the pathogenesis of salmonella-induced diarrhea has been hampered by the lack of a suitable mouse model. after a dose of oral kanamycin, salmonella-infected congenic balb/c.d2(nrampg169) mice, which carry a wild-type nramp1 gene, develop clear manifestations of diarrhea. we used this model to ...201324001788
identification of the first blacmy-2 gene in salmonella enterica serovar typhimurium isolates obtained from cases of paediatric diarrhoea illness detected in south america.the objectives of this study were to investigate clinical isolates of salmonella enterica serovar typhimurium resistant to β-lactam antibiotics, to characterise their mechanisms of antibiotic resistance and to evaluate the possible biological cost of expressing resistance genes. two oxyimino-cephalosporin-resistant salmonella isolates obtained from children with diarrhoea were characterised. the occurrence of plasmid-encoded blacmy-2 genes was confirmed by molecular methods and conjugation assay ...201327873624
mechanism of antimicrobial action of sodium metasilicate against salmonella enterica serovar typhimurium.sodium metasilicate (sms) is an alkaline antimicrobial approved by the u.s. department of agriculture for use in poultry processing and ready-to-eat poultry products. the objectives of this study were to determine the effectiveness of sms against salmonella enterica serovar typhimurium in suspension and to elucidate the antimicrobial mechanism of action of sms. salmonella typhimurium (atcc 14028) was exposed to 0 (positive control), 0.5%, 1%, 2% (wt/vol) sms and 0.1 n naoh (high ph) solutions fo ...201323980709
epithelial entry rather than the ensuing systemic immune response determines the pathogenicity of two salmonella enterica serovar typhimurium strains in a mouse model.most studies of salmonella enterica serovar typhimurium infection focus only on the pathogenicity of one strain. we investigated whether differences in pathogenicity of two wild-type s. typhimurium strains; dt120 and sl1344, were related to gut invasion or the resulting immune response. oral administration of a ten-fold lower number of sl1344 (10(6) cfu) as compared to dt120 (10(7) cfu) resulted in higher bacterial counts in liver and lymph nodes, and led to massive neutrophil infiltration of th ...201323978790
innate immune detection of flagellin positively and negatively regulates salmonella infection.salmonella enterica serovar typhimurium is a flagellated bacterium and one of the leading causes of gastroenteritis in humans. bacterial flagellin is required for motility and also a prime target of the innate immune system. innate immune recognition of flagellin is mediated by at least two independent pathways, tlr5 and naip5-naip6/nlrc4/caspase-1. the functional significance of each of the two independent flagellin recognition systems for host defense against wild type salmonella infection is ...201323977202
emergence of pulsed electric fields resistance in salmonella enterica serovar typhimurium sl1344.in this investigation we selected and isolated a culture derived from salmonella enterica serovar typhimurium sl1344 with stable increased resistance to pulsed electric fields (pef) after repeated rounds of pef treatment and outgrowth of survivors. the resulting culture showed a higher resistance to pef treatments under different treatment conditions. the acquisition of pef resistance was only observed in stationary phase cells. the cytoplasmic membrane of the resistant variant showed a higher r ...201323973831
roles of yehz, a putative osmoprotectant transporter, in tempering growth of salmonella enterica serovar typhimurium.salmonella, a main cause of foodborne diseases, encounters a variety of environmental stresses and overcomes the stresses by multiple resistance strategies. one of the general responses to hyperosmotic stress is to import or produce compatible solutes so that cells maintain fluid balance and protect proteins and lipids from denaturation. the prop and prou systems are the main transport systems for compatible solutes. the osmu system, recently identified as a third osmoprotectant transport system ...201323966021
signal peptide etiquette during assembly of a complex respiratory enzyme.salmonella enterica serovar typhimurium is a gram-negative pathogen capable of respiration with a number of terminal electron acceptors. tetrathionate reductase is important for the infection process and is encoded by the ttrbca operon where ttra and ttrb are metallocofactor-containing proteins targeted to the periplasmic side of the membrane by two different tat targeting peptides. in this work, the inter-relationship between these two signal peptides has been explored. molecular genetics and b ...201323961722
diverse secreted effectors are required for salmonella persistence in a mouse infection model.salmonella enterica serovar typhimurium causes typhoid-like disease in mice and is a model of typhoid fever in humans. one of the hallmarks of typhoid is persistence, the ability of the bacteria to survive in the host weeks after infection. virulence factors called effectors facilitate this process by direct transfer to the cytoplasm of infected cells thereby subverting cellular processes. secretion of effectors to the cell cytoplasm takes place through multiple routes, including two separate ty ...201323950998
the putative thiosulfate sulfurtransferases pspe and glpe contribute to virulence of salmonella typhimurium in the mouse model of systemic disease.the phage-shock protein pspe and glpe of the glycerol 3-phosphate regulon of salmonella enterica serovar typhimurium are predicted to belong to the class of thiosulfate sulfurtransferases, enzymes that traffic sulfur between molecules. in the present study we demonstrated that the two genes contribute to s. typhimurium virulence, as a glpe and pspe double deletion strain showed significantly decreased virulence in a mouse model of systemic infection. however, challenge of cultured epithelial cel ...201323940650
a low-ph medium in vitro or the environment within a macrophage decreases the transcriptional levels of fima, fimz and lrp in salmonella enterica serovar typhimurium.many salmonella typhimurium isolates produce type 1 fimbriae and exhibit fimbrial phase variation in vitro. static broth culture favours the production of fimbriae, while solid agar medium inhibits the generation of these appendages. little information is available regarding whether s. typhimurium continues to produce type 1 fimbriae during in vivo growth. we used a type 1 fimbrial phase-variable strain s. typhimurium lb5010 and its derivatives to infect raw 264.7 macrophages. following entry in ...201323938383
pathoadaptive mutations in salmonella enterica isolated after serial passage in mice.how pathogenic bacteria adapt and evolve in the complex and variable environment of the host remains a largely unresolved question. here we have used whole genome sequencing of salmonella enterica serovar typhimurium lt2 populations serially passaged in mice to identify mutations that adapt bacteria to systemic growth in mice. we found unique pathoadaptive mutations in two global regulators, phoq and stpa, which increase the competitive indexes of the bacteria 3- to 5-fold. also, all mouse-adapt ...201323936152
15-deoxy-δ12,14-prostaglandin j2 inhibits macrophage colonization by salmonella enterica serovar typhimurium.15-deoxy-δ(12,14)-prostaglandin j2 (15d-pgj2) is an anti-inflammatory downstream product of the cyclooxygenase enzymes. it has been implicated to play a protective role in a variety of inflammatory mediated diseases, including rheumatoid arthritis, neural damage, and myocardial infarctions. here we show that 15d-pgj2 also plays a role in salmonella infection. salmonella enterica typhimurium is a gram-negative facultative intracellular pathogen that is able to survive and replicate inside phagocy ...201323922794
salmonella enterica serovar typhimurium baesr two-component system positively regulates soda in response to ciprofloxacin.in response to antibiotics, bacteria activate regulatory systems that control the expression of genes that participate in detoxifying these compounds, like multidrug efflux systems. we previously demonstrated that the baesr two-component system from salmonella enterica serovar typhimurium (s. typhimurium) participates in the detection of ciprofloxacin, a bactericidal antibiotic, and in the positive regulation of mdta, an efflux pump implicated in antibiotic resistance. in the present work, we pr ...201323918818
in vitro and in vivo investigation on genomic stability of salmonella enterica typhimurium dt41 obtained from broiler breeders in denmark.salmonella enterica serovar typhimurium phage type dt41 has previously been identified from salmonella-positive broiler breeder flocks in denmark and isolates obtained from different flocks have demonstrated major diversity by multiple-locus variable-number tandem-repeats analysis (mlva) typing. to elucidate whether the high diversity observed by mlva was related to multiple independent introductions at farm level or genetic instability of markers, we investigated the genomic stability of differ ...201323915994
prevalence and characterization of apramycin-resistant salmonella enterica serotype typhimurium isolated from healthy and diseased pigs in korea during 1998 through 2009.apramycin resistance was observed in 22.8% (81 of 355) of salmonella typhimurium isolates collected from pigs from 1998 through 2009 in korea. all apramycin-resistant salmonella typhimurium isolates also were cross-resistant to gentamicin and tobramycin. among the seven types of aminoglycoside resistance genes tested, only four types were detected in the apramycin-resistant salmonella typhimurium isolates: aac (3)-iv, aac (3)-ii, aac (3)-iii, and ant (2'')-i. although the aac (3)-iv gene was fou ...201323905803
combined stimulation of toll-like receptor 5 and nod1 strongly potentiates activity of nf-κb, resulting in enhanced innate immune reactions and resistance to salmonella enterica serovar typhimurium infection.pathogen recognition receptors (prrs) are essential components of host innate immune systems that detect specific conserved pathogen-associated molecular patterns (pamps) presented by microorganisms. members of two families of prrs, transmembrane toll-like receptors (tlrs 1, 2, 4, 5, and 6) and cytosolic nod receptors (nod1 and nod2), are stimulated upon recognition of various bacterial pamps. such stimulation leads to induction of a number of immune defense reactions, mainly triggered via activ ...201323897616
complete genome sequence of salmonella enterica serovar typhimurium u288.salmonella enterica serovar typhimurium u288 has firmly established itself within the united kingdom pig production industry. the prevalence of this highly pathogenic multidrug-resistant serovar at such a critical point in the food chain is therefore of great concern. to enhance our understanding of this microorganism, whole-genome and plasmid sequencing was performed.201323887910
antimicrobial resistance of human salmonella enterica serovar typhimurium u302 strains: prevalence of r-type assut in slovakia, 2006-2011.salmonella enterica serovar typhimurium is a common cause of non-typhoid salmonellosis in humans. since 2006, an increase in the human infections caused by u302 phage type in slovakia has been documented and, from 2006 to 2011, a total of 291 u302 human strains were isolated. antimicrobial susceptibility testing demonstrated that these strains had a high overall antimicrobial resistance and 244 (83.8%) of the tested strains were multidrug-resistant (mdr). the most prevalent resistance was to amp ...201323883849
emergence of a multidrug-resistant (assuttm) strain of salmonella enterica serovar typhimurium dt120 in england in 2011 and the use of multiple-locus variable-number tandem-repeat analysis in supporting outbreak investigations.in summer 2011, two outbreaks of a unique, multidrug-resistant strain of salmonella enterica serovar typhimurium phage type 120 (dt120) occurred mainly in the midlands, england. the first outbreak occurred among guests attending a wedding in july 2011 ('wedding outbreak'), followed by a more geographically dispersed outbreak in august and september 2011 ('midlands outbreak'). fifty-one cases were confirmed. detailed epidemiological and environmental health investigations suggested that pork was ...201323869962
a multi-omic view of host-pathogen-commensal interplay in salmonella-mediated intestinal infection.the potential for commensal microorganisms indigenous to a host (the 'microbiome' or 'microbiota') to alter infection outcome by influencing host-pathogen interplay is largely unknown. we used a multi-omics "systems" approach, incorporating proteomics, metabolomics, glycomics, and metagenomics, to explore the molecular interplay between the murine host, the pathogen salmonella enterica serovar typhimurium (s. typhimurium), and commensal gut microorganisms during intestinal infection with s. typh ...201323840608
antimicrobial activity of plant compounds against salmonella typhimurium dt104 in ground pork and the influence of heat and storage on the antimicrobial activity.salmonella enterica is a predominant foodborne pathogen that causes diarrheal illness worldwide. a potential method of inhibiting pathogenic bacterial growth in meat is through the introduction of plant-derived antimicrobials. the objectives of this study were to investigate the influence of heat (70°c for 5 min) and subsequent cold storage (4°c up to 7 days) on the effectiveness of oregano and cinnamon essential oils and powdered olive and apple extracts against salmonella enterica serovar typh ...201323834804
postharvest handling conditions affect internalization of salmonella in baby spinach during washing.internalization of foodborne pathogens in fruits and vegetables is an increasing safety concern. the aim of this research was to assess the potential for internalization of an enteric pathogen (salmonella enterica serotype typhimurium) in a leafy vegetable (baby spinach) during washing as influenced by three postharvest handling conditions: (i) illumination, (ii) negative temperature differential, and (iii) relative humidity (rh). to compare these potential postharvest handling conditions, leave ...201323834788
salmonella enterica serovar typhimurium virulence-resistance plasmids derived from the pslt carrying nonconventional class 1 integrons with dfra12 gene in their variable region and sul3 in the 3' conserved segment.drug-resistant derivatives of serovar-specific virulence plasmids, such as pslt, in clinically-relevant salmonella enterica serovar typhimurium strains, represent a threat for human health. we have analysed 14 s. typhimurium isolates recovered in italy and the united kingdom from swine and from cases of human infection for the presence of virulence-resistance (vr) plasmids. they were negative for the multidrug resistance (mdr) region of the salmonella genomic island 1 (sgi1), but expressed resis ...201323808958
expansion of salmonella enterica serovar typhimurium st34 clone carrying multiple resistance determinants in china. 201323796940
draft genome sequences for ten salmonella enterica serovar typhimurium phage type 135 variants.salmonella enterica serovar typhimurium (s. typhimurium) is a common cause of gastroenteritis in humans. here, we report the draft genome sequences of 10 isolates of an s. typhimurium phage type 135 variant that is linked to egg-associated outbreaks in tasmania, australia.201323792739
longitudinal study of distributions of similar antimicrobial-resistant salmonella serovars in pigs and their environment in two distinct swine production systems.the aim of this longitudinal study was to determine and compare the prevalences and genotypic profiles of antimicrobial-resistant (ar) salmonella isolates from pigs reared in antimicrobial-free (abf) and conventional production systems at farm, at slaughter, and in their environment. we collected 2,889 pig fecal and 2,122 environmental (feed, water, soil, lagoon, truck, and floor swabs) samples from 10 conventional and eight abf longitudinal cohorts at different stages of production (farrowing, ...201323793629
unsaturated long chain free fatty acids are input signals of the salmonella enterica phop/phoq regulatory system.the salmonella enterica serovar typhimurium phop/phoq system has largely been studied as a paradigmatic two-component regulatory system not only to dissect structural and functional aspects of signal transduction in bacteria but also to gain knowledge about the versatile devices that have evolved allowing a pathogenic bacterium to adjust to or counteract environmental stressful conditions along its life cycle. mg(2+) limitation, acidic ph, and the presence of cationic antimicrobial peptides have ...201323782700
β-1,3/1,6-glucan alleviated intestinal mucosal barrier impairment of broiler chickens challenged with salmonella enterica serovar typhimurium.this study investigated the protective effect of β-1,3/1,6-glucan on gut morphology, intestinal epithelial tight junctions, and bacterial translocation of broiler chickens challenged with salmonella enterica serovar typhimurium. ninety salmonella-free arbor acre male broiler chickens were randomly divided into 3 groups: negative control group (nc), salmonella typhimurium-infected positive group (pc), and the salmonella typhimurium-infected group with dietary 100 mg/kg of β-1,3/1,6-glucan supplem ...201323776263
evidence of metabolic switching and implications for food safety from the phenome(s) of salmonella enterica serovar typhimurium dt104 cultured at selected points across the pork production food chain.salmonella enterica serovar typhimurium dt104 is a recognized food-borne pathogen that displays a multidrug-resistant phenotype and that is associated with systemic infections. at one extreme of the food chain, this bacterium can infect humans, limiting the treatment options available and thereby contributing to increased morbidity and mortality. although the antibiotic resistance profile is well defined, little is known about other phenotypes that may be expressed by this pathogen at key points ...201323770904
attenuated salmonella enterica serovar typhimurium lacking the znuabc transporter: an efficacious orally-administered mucosal vaccine against salmonellosis in pigs.we have recently demonstrated that an attenuated strain of salmonella enterica serovar typhimurium unable to synthesize the zinc transporter znuabc (s. typhimurium δznuabc), is able to protect mice against systemic and enteric salmonellosis and is safe in pigs. here, we have tested the protective effects of s. typhimurium δznuabc in pigs. resistance to challenge with the fully virulent strain s. typhimurium atcc 14028 was assessed in animals vaccinated with s. typhimurium δznuabc (two dosages te ...201323770333
evaluation of the efficiency of synthesized efflux pump inhibitors on salmonella enterica ser. typhimurium cells.multidrug efflux pump inhibitors have a great potential as pharmacological agents that increase the drug susceptibility of bacterial pathogens. our study was focused on the synthesis and evaluation of the efficiency of resistance-nodulation-division (rnd) family efflux pump inhibitors. the efficiency of these inhibitors was investigated on salmonella enterica ser. typhimurium cells using tetraphenylphosphonium (tpp(+) ) and ethidium cations as the efflux pump substrates. results of our study ind ...201323763959
the systemic immune state of super-shedder mice is characterized by a unique neutrophil-dependent blunting of th1 responses.host-to-host transmission of a pathogen ensures its successful propagation and maintenance within a host population. a striking feature of disease transmission is the heterogeneity in host infectiousness. it has been proposed that within a host population, 20% of the infected hosts, termed super-shedders, are responsible for 80% of disease transmission. however, very little is known about the immune state of these super-shedders. in this study, we used the model organism salmonella enterica sero ...201323754944
role of murine intestinal interleukin-1 receptor 1-expressing lymphoid tissue inducer-like cells in salmonella infection.interleukin (il)-1 signaling plays a critical role in intestinal immunology. here, we report that the major population of intestinal lamina propria lymphocytes expressing il-1 receptor 1 (il-1r1) is the lymphoid tissue inducer (lti)-like cell, a type of innate lymphoid cell. these cells are significant producers of il-22, and this il-22 production depends on il-1r1 signaling. lti-like cells are required for defense against salmonella enterica serovar typhimurium. moreover, colonic lti-like cell ...201323750260
oxidoreductases that act as conditional virulence suppressors in salmonella enterica serovar typhimurium.in salmonella enterica serovar typhimurium, oxidoreductases of the thioredoxin superfamily contribute to bacterial invasiveness, intracellular replication and to the virulence in balb/c mice as well as in the soil nematode caenorhabditis elegans. the scsabcd gene cluster, present in many but not all enteric bacteria, codes for four putative oxidoreductases of the thioredoxin superfamily. here we have analyzed the potential role of the scs genes in oxidative stress tolerance and virulence in s. t ...201323750221
length control of the flagellar hook in a temperature-sensitive flge mutant of salmonella enterica serovar typhimurium.the flagellar hook is a short, curved, extracellular structure located between the basal body and the filament. the hook is composed of the flge protein. in this study, we analyzed flagellum assembly in a temperature-sensitive flge mutant of salmonella enterica serovar typhimurium. when the mutant cells were grown at 30°c, they produced flagella of a normal length (71% of the population) and short hooks without filaments (26%). at 37°c, 70% of the basal bodies lacked hooks, and intact flagella m ...201323749974
identification and characterization of a novel flagellum-dependent salmonella-infecting bacteriophage, ieps5.a novel flagellatropic phage of salmonella enterica serovar typhimurium, called ieps5, was isolated and characterized. ieps5 has an icosahedral head and a long noncontractile tail with a tail fiber. genome sequencing revealed a double-stranded dna of 59,254 bp having 73 open reading frames (orfs). to identify the receptor for ieps5, tn5 transposon insertion mutants of s. typhimurium sl1344 that were resistant to the phage were isolated. all of the phage-resistant mutants were found to have mutat ...201323747700
spread of oqxab in salmonella enterica serotype typhimurium predominantly by inchi2 plasmids.to investigate the prevalence and genetic environment of the multiresistance gene oqxab in salmonella enterica serotype typhimurium isolated from food-producing animals.201323737490
potential therapeutic anti-tumor effect of a salmonella-based vaccine.one of the major obstacles to achieving complete eradication of tumors, even in the presence of circulating tumor-specific immunity, is the tumor-induced immunosuppressive environment, which includes myeloid-derived suppressor cells and regulatory t cells. attenuated microorganisms have emerged as candidates for a novel anti-cancer approach in which they enhance anti-cancer immunity by boosting the innate immune system. herein, we will discuss current innate-immunity activating strategies for an ...201323733040
survival of acid adapted and non-acid adapted salmonella typhimurium in pasteurized orange juice and yogurt under different storage temperatures.the survival capacity of salmonella enterica serovar typhimurium acid adapted and non-acid adapted cells was monitored in pasteurized yogurt (ph 4.1) and orange juice (ph 3.6) during storage at different temperatures (4, 10, 25 and 37 ). acid adapted and non-acid adapted cells were obtained by means of their growth for 36 h in brain heart infusion broth acidified at ph 4.8 with citric acid and buffered (ph 7.0) brain heart infusion broth, respectively. s. typhimurium showed a great ability to su ...201323729421
crystal structure of the periplasmic disulfide-bond isomerase dsbc from salmonella enterica serovar typhimurium and the mechanistic implications.the disulfide-bond isomerase dsbc plays a crucial role in the folding of bacterial proteins in the periplasmic space. dsbc has a v-shaped dimeric structure with two domains, and cys98 in the c-terminal domain attacks inappropriate disulfide bonds in substrate proteins due to its high nucleophilic activity. in this article, we present the crystal structure of dsbc from salmonella enterica serovar typhimurium. we evaluated the conserved residues asp95 and arg125, which are located close to cys98. ...201323726983
circadian clock regulates the host response to salmonella.organisms adapt to day-night cycles through highly specialized circadian machinery, whose molecular components anticipate and drive changes in organism behavior and metabolism. although many effectors of the immune system are known to follow daily oscillations, the role of the circadian clock in the immune response to acute infections is not understood. here we show that the circadian clock modulates the inflammatory response during acute infection with the pathogen salmonella enterica serovar t ...201323716692
choice of bacterial growth medium alters the transcriptome and phenotype of salmonella enterica serovar typhimurium.the type of bacterial culture medium is an important consideration during design of any experimental protocol. the aim of this study was to understand the impact of medium choice on bacterial gene expression and physiology by comparing the transcriptome of salmonella enterica sl1344 after growth in the widely used lb broth or the rationally designed mops minimal medium. transcriptomics showed that after growth in mops minimal media, compared to lb, there was increased expression of 42 genes invo ...201323704954
molecular characterization of salmonella enterica serovar typhimurium isolated from human, food, and animal sources in malaysia.salmonella typhimurium is an important nontyphoidal salmonella serovar associated with foodborne diseases in many parts of the world. this organism is the major causative agent of nontyphoidal salmonellosis in malaysia. we aimed to investigate the genetic profiles of the strains isolated from clinical, zoonotic, and dietary sources in malaysia using multilocus variable number tandem repeat analysis (mlva) and pulsed-field gel electrophoresis (pfge). by focusing on the 5 common variable number ta ...201323698477
genomic analysis of salmonella enterica serovar typhimurium definitive phage type 104. 201323697578
expression, purification, crystallization and preliminary x-ray diffraction analysis of a core fragment of flgg, a bacterial flagellar rod protein.flgg is a bacterial flagellar rod protein and constructs the distal rod connecting to the hook. flgg of salmonella enterica serovar typhimurium is a 260-amino-acid protein composed of a folded core region and n- and c-terminal regions that are unfolded in solution. a core fragment of flgg (flgg47-227) was expressed, purified and crystallized. crystals of native and semet-labelled flgg47-227 were obtained by the sitting-drop vapour-diffusion technique with peg mme 2000 as precipitant. the native ...201323695574
the lipopolysaccharide modification regulator pmra limits salmonella virulence by repressing the type three-secretion system spi/ssa.the regulatory protein pmra controls expression of lipopolysaccharide (lps) modification genes in salmonella enterica serovar typhimurium, the etiologic agent of human gastroenteritis and murine typhoid fever. pmra-dependent lps modifications confer resistance to serum, fe(3+), and several antimicrobial peptides, suggesting that the pmra gene is required for salmonella virulence. we now report that, surprisingly, a pmra null mutant is actually hypervirulent when inoculated i.p. into c3h/hen mice ...201323690578
the use of factorial design, image analysis, and an efficiency calculation for multiplex pcr optimization.the quality of multiplex polymerase chain reaction (pcr) assays depends on several factors. therefore, it is important to establish the optimal conditions to achieve efficient amplification. the objective of this study was to implement a 5 × 4 factorial design combined with image analysis using agarose gels and an efficiency calculation to optimize a multiplex pcr assays for the detection of salmonella enterica serovar typhimurium.201323686781
clpp deletion causes attenuation of salmonella typhimurium virulence through mis-regulation of rpos and indirect control of csra and the spi genes.salmonella enterica serovar typhimurium requires the type iii secretion system encoded by salmonella pathogenicity island 1 (spi1) and controlled by the master regulator, hila, to penetrate the intestinal epithelium. numerous regulators affect virulence through influence on this system, including the proteolytic component clpp, the stationary phase regulator rpos and the carbon-storage regulator csra. however, the mechanism behind the clpp regulation is not fully understood. to elucidate this we ...201323676436
prop is required for the survival of desiccated salmonella enterica serovar typhimurium cells on a stainless steel surface.consumers trust commercial food production to be safe, and it is important to strive to improve food safety at every level. several outbreaks of food-borne disease have been caused by salmonella strains associated with dried food. currently we do not know the mechanisms used by salmonella enterica serovar typhimurium to survive in desiccated environments. the aim of this study was to discover the responses of s. typhimurium st4/74 at the transcriptional level to desiccation on a stainless steel ...201323666329
raon, a small rna encoded within salmonella pathogenicity island-11, confers resistance to macrophage-induced stress.bacterial small non-coding rnas act as important regulators that control numerous cellular processes. here we identified raon, a novel small rna encoded in the csph-enve intergenic region on salmonella pathogenicity island-11 (spi-11). raon contributes to survival under conditions of acid and oxidative stress combined with nutrient limitation, which partially mimic the intramacrophage environment. indeed, inactivation of raon reduces the intramacrophage replication of salmonella enterica serovar ...201323657681
biotin sulfoxide reductase contributes to oxidative stress tolerance and virulence in salmonella enterica serovar typhimurium.oxidative stress converts sulfur residues of molecules like biotin and methionine into their oxidized forms. here we show that the biotin sulfoxide reductase bisc of salmonella enterica serovar typhimurium (s. typhimurium) repairs both oxidized biotin and oxidized methionine. exposure to h2o2 in vitro reduced survival of a s. typhimurium δbisc mutant. furthermore, replication of the δbisc mutant inside ifn-γ activated macrophages was reduced. in vitro tolerance of the mutant to h2o2 was restored ...201323657680
conflicting roles for a cell surface modification in salmonella.chemical modifications of components of the bacterial cell envelope can enhance resistance to antimicrobial agents. why then are such modifications produced only under specific conditions? here, we address this question by examining the role of regulated variations in o-antigen length in the lipopolysaccharide (lps), a glycolipid that forms most of the outer leaflet of the outer membrane in gram-negative bacteria. we determined that activation of the pmra/pmrb two-component system, which is the ...201323646936
intestinal invasion of salmonella enterica serovar typhimurium in the avian host is dose dependent and does not depend on motility and chemotaxis.salmonella enterica serotype typhimurium (s. typhimurium) can invade in the intestine of the avian host, and knowledge on the mechanisms that govern this is potentially important for prevention of disease. this study investigated the invasion of s. typhimurium in the avian host and to which extent it depended on motility and chemotaxis. wild type and previously well-characterized transposon mutants in flagella genes flic and fljb and in chemotaxis genes chea, cheb and cher were used as challenge ...201323642416
a simple technique based on a single optical trap for the determination of bacterial swimming pattern.bacterial motility is associated to a wide range of biological processes and it plays a key role in the virulence of many pathogens. here we describe a method to distinguish the dynamic properties of bacteria by analyzing the statistical functions derived from the trajectories of a bacterium trapped by a single optical beam. the approach is based on the model of the rotation of a solid optically trapped sphere. the technique is easily implemented in a biological laboratory, since with only a sma ...201323637869
nontyphoid salmonella infection: microbiology, clinical features, and antimicrobial therapy.nontyphoid salmonella is the most common bacterial pathogen causing gastrointestinal infection worldwide. most nontyphoid salmonella infection is limited to uncomplicated gastroenteritis that seldom requires antimicrobial treatment. nevertheless, invasive infections, such as bacteremia, osteomyelitis, and meningitis, may occur and require antimicrobial therapy. continuous genetic and genomic evolution in salmonella leading to increased virulence and resistance to multiple drugs are of significan ...201323597525
new sub-family of lysozyme-like proteins shows no catalytic activity: crystallographic and biochemical study of stm3605 protein from salmonella typhimurium.phage viruses that infect prokaryotes integrate their genome into the host chromosome; thus, microbial genomes typically contain genetic remnants of both recent and ancient phage infections. often phage genes occur in clusters of atypical g+c content that reflect integration of the foreign dna. however, some phage genes occur in isolation without other phage gene neighbors, probably resulting from horizontal gene transfer. in these cases, the phage gene product is unlikely to function as a compo ...201323572252
salmonella modulates metabolism during growth under conditions that induce expression of virulence genes.salmonella enterica serovar typhimurium (s. typhimurium) is a facultative pathogen that uses complex mechanisms to invade and proliferate within mammalian host cells. to investigate possible contributions of metabolic processes to virulence in s. typhimurium grown under conditions known to induce expression of virulence genes, we used a metabolomics-driven systems biology approach coupled with genome-scale modeling. first, we identified distinct metabolite profiles associated with bacteria grown ...201323559334
salmonella enterica serovar typhimurium skills to succeed in the host: virulence and regulation.salmonella enterica serovar typhimurium is a primary enteric pathogen infecting both humans and animals. infection begins with the ingestion of contaminated food or water so that salmonellae reach the intestinal epithelium and trigger gastrointestinal disease. in some patients the infection spreads upon invasion of the intestinal epithelium, internalization within phagocytes, and subsequent dissemination. in that case, antimicrobial therapy, based on fluoroquinolones and expanded-spectrum cephal ...201323554419
profiling the gastrointestinal microbiota in response to salmonella: low versus high salmonella shedding in the natural porcine host.controlling salmonella in the food chain is complicated by the ability of salmonella to colonize livestock without causing clinical symptoms/disease. salmonella-carrier animals are a significant reservoir for contamination of naïve animals, the environment, and our food supply. salmonella carriage and shedding in pigs varies greatly both experimentally and on-farm. to investigate the dynamics between the porcine intestinal microbiota and salmonella shedding, we temporally profiled the microbiota ...201323535116
identification of an outer membrane protein of salmonella enterica serovar typhimurium as a potential vaccine candidate for salmonellosis in mice.we report our investigation of the functions of pagn in salmonella pathogenesis and its potential as a vaccine candidate. further investigation conducted in this study indicates that the outer membrane protein pagn is important for salmonella adhesion/invasion of epithelial cells as well as bacterial virulence. when pagn was deleted from salmonella enterica serovar typhimurium (s. typhimurium), the adhesion and invasion of ht-29 epithelial cells was significantly decreased compared with the wild ...201323485513
wild birds carry similar salmonella enterica serovar typhimurium strains to those found in domestic animals and livestock.the objective of this study was to investigate the hypothesis that some sporadic salmonella infections in domesticated animals may be associated with salmonella infections originating from garden birds. phage type and antimicrobial resistance details of isolates of s. typhimurium obtained from wild birds were comparable with those from s. typhimurium infections from domesticated animals or livestock between 2002 and 2010. a small panel of s. typhimurium isolates (n=37) were characterised by mult ...201323481141
delivery of the co-expression plasmid pendo-si-stat3 by attenuated salmonella serovar typhimurium for prostate cancer treatment.to investigate the therapeutic utility of an attenuated bacterium carrying a plasmid that co-expresses endostatin, an inhibitor of tumor neovasculogenesis, and a shrna that targets stat3 to suppress prostate cancer growth.201323463096
salmonella enterica causes more severe inflammatory disease in c57/bl6 nramp1g169 mice than sv129s6 mice.salmonella enterica serovar typhimurium (s. typhimurium) causes systemic inflammatory disease in mice by colonizing cells of the mononuclear leukocyte lineage. mouse strains resistant to s. typhimurium, including sv129s6, have an intact nramp1 (slc11a1) allele and survive acute infection, whereas c57/bl6 mice, homozygous for a mutant nramp1 allele, nramp1(g169d) , develop lethal infections. restoration of nramp1 (c57/bl6 nramp1(g169) ) reestablishes resistance to s. typhimurium; mice survive at ...201323446432
the actin-polymerizing activity of sipa is not essential for salmonella enterica serovar typhimurium-induced mucosal inflammation.salmonella enterica serovar typhimurium depends on type iii secretion systems to inject effector proteins into host cells to promote bacterial invasion and to induce intestinal inflammation. sipa, a type iii effector, is known to play important roles in both the invasion and the elicitation of intestinal inflammation. the actin-modulating activity of sipa has been shown to promote salmonella entry into epithelial cells. to investigate whether the actin-modulating activity of sipa is required for ...201323439302
no protective effects of high-dosage dietary zinc oxide on weaned pigs infected with salmonella enterica serovar typhimurium dt104.twenty-eight-day-old weaned pigs were fed diets with a low (lzn), medium (mzn), or high (mzn) zn concentration (50 to 80, 150, or 2,500 mg zn/kg of diet, respectively) provided as zinc oxide (zno)(24 pigs per group). they were infected orally with salmonella enterica serovar typhimurium dt104 on day 32. salmonellae were cultivated from feces (up to 42 days postinfection [dpi]) and organs (2 and 42 dpi). activation of the adaptive systemic and mucosal immune systems was investigated by recording ...201323435881
an essential role for the atg8 ortholog lc3c in antibacterial autophagy.autophagy defends the mammalian cytosol against bacterial invasion. efficient bacterial engulfment by autophagy requires cargo receptors that bind (a) homolog(s) of the ubiquitin-like protein atg8 on the phagophore membrane. the existence of multiple atg8 orthologs in higher eukaryotes suggests that they may perform distinct functions. however, no specific role has been assigned to any mammalian atg8 ortholog. we recently discovered that the autophagy receptor calcoco2/ndp52, which detects cytos ...201323434839
reconciling a salmonella enterica metabolic model with experimental data confirms that overexpression of the glyoxylate shunt can rescue a lethal ppc deletion mutant.the in silico reconstruction of metabolic networks has become an effective and useful systems biology approach to predict and explain many different cellular phenotypes. when simulation outputs do not match experimental data, the source of the inconsistency can often be traced to incomplete biological information that is consequently not captured in the model. to address this problem, general approaches continue to be needed that can suggest experimentally testable hypotheses to reconcile incons ...201323432746
regulation of chemokines, ccl3 and ccl4, by interferon γ and nitric oxide synthase 2 in mouse macrophages and during salmonella enterica serovar typhimurium infection.interferon γ (ifn-γ) increases the expression of multiple genes and responses; however, the mechanisms by which ifn-γ downmodulates cellular responses is not well understood. in this study, the repression of ccl3 and ccl4 by ifn-γ and nitric oxide synthase 2 (nos2) in macrophages and upon salmonella typhimurium infection of mice was investigated.201323431040
stabilization of cooperative virulence by the expression of an avirulent phenotype.pathogens often infect hosts through collective actions: they secrete growth-promoting compounds or virulence factors, or evoke host reactions that fuel the colonization of the host. such behaviours are vulnerable to the rise of mutants that benefit from the collective action without contributing to it; how these behaviours can be evolutionarily stable is not well understood. we address this question using the intestinal pathogen salmonella enterica serovar typhimurium (hereafter termed s. typhi ...201323426324
inactivation of salmonella enterica serovar typhimurium and quality maintenance of cherry tomatoes treated with gaseous essential oils.the antimicrobial activity of the essential oils (eos) from cinnamon bark, oregano, mustard, and of their major components cinnamaldehyde, carvacrol, and allyl isothiocyanate (ait) was evaluated as a gaseous treatment to reduce salmonella enterica serovar typhimurium in vitro and on tomatoes. in vitro tests showed that mustard eo and ait had the greatest inhibition of salmonella, followed by cinnamon eo and cinnamaldehyde, while oregano and carvacrol showed the least inhibition. scanning electro ...201323398191
rida proteins prevent metabolic damage inflicted by plp-dependent dehydratases in all domains of life.pyridoxal 5'-phosphate (plp) is a coenzyme synthesized by all forms of life. relevant to the work reported here is the mechanism of the plp-dependent threonine/serine dehydratases, which generate reactive enamine/imine intermediates that are converted to keto acids by members of the rida family of enzymes. the rida protein of salmonella enterica serovar typhimurium lt2 is the founding member of this broadly conserved family of proteins (formerly known as yjgf/yer057c/uk114). rida proteins were r ...201323386433
rac and rab gtpases dual effector nischarin regulates vesicle maturation to facilitate survival of intracellular bacteria.the intracellular pathogenic bacterium salmonella enterica serovar typhimurium (salmonella) relies on acidification of the salmonella-containing vacuole (scv) for survival inside host cells. the transport and fusion of membrane-bound compartments in a cell is regulated by small gtpases, including rac and members of the rab gtpase family, and their effector proteins. however, the role of these components in survival of intracellular pathogens is not completely understood. here, we identify nischa ...201323386062
cooperation of the multidrug efflux pump and lipopolysaccharides in the intrinsic antibiotic resistance of salmonella enterica serovar typhimurium.in gram-negative bacteria, drug susceptibility is associated with multidrug efflux systems and an outer membrane (om) barrier. previous studies revealed that salmonella enterica serovar typhimurium has 10 functional drug efflux pumps. among them, acrb is a major factor to maintain the intrinsic drug resistance in this organism. the lipopolysaccharide (lps) content of om is also important for resistance to lipophilic drugs; however, the interplay between the multidrug efflux pump and lps in the i ...201323378414
colonization and internalization of salmonella enterica in tomato plants.the consumption of fresh tomatoes has been linked to numerous food-borne outbreaks involving various serovars of salmonella enterica. recent advances in our understanding of plant-microbe interactions have shown that human enteric pathogenic bacteria, including s. enterica, are adapted to survive in the plant environment. in this study, tomato plants (solanum lycopersicum cv. micro-tom) grown in sandy loam soil from virginia's eastern shore (ves) were inoculated with s. enterica serovars to eval ...201323377940
pmdt1, a small cole1-like plasmid mobilizing a new variant of the aac(6')-ib-cr gene in salmonella enterica serovar typhimurium.to characterize a 5.9 kb aac(6')-ib-cr-harbouring plasmid that was detected in a clinical salmonella typhimurium dt104b strain.201323361643
stochasticity in colonial growth dynamics of individual bacterial cells.conventional bacterial growth studies rely on large bacterial populations without considering the individual cells. individual cells, however, can exhibit marked behavioral heterogeneity. here, we present experimental observations on the colonial growth of 220 individual cells of salmonella enterica serotype typhimurium using time-lapse microscopy videos. we found a highly heterogeneous behavior. some cells did not grow, showing filamentation or lysis before division. cells that were able to gro ...201323354712
development of ceftriaxone resistance affects the virulence properties of salmonella enterica serotype typhimurium strains.development of antibiotic resistance may alter the virulence properties of bacterial organisms. in this study, nine clinical ceftriaxone-susceptible salmonella enterica serotype typhimurium strains were subjected to stepwise selection with increasing concentrations of ceftriaxone in culture media. mutations in virulence-associated genes and antibiotic efflux genes were analyzed by polymerase chain reaction (pcr) and dna sequencing. the expression levels of virulence genes inva and stn as well as ...201323320420
salmonella polarises peptide-mhc-ii presentation towards an unconventional type b cd4+ t-cell response.distinct peptide-mhc-ii complexes, recognised by type a and b cd4(+) t-cell subsets, are generated when antigen is loaded in different intracellular compartments. conventional type a t cells recognize their peptide epitope regardless of the route of processing, whereas unconventional type b t cells only recognise exogenously supplied peptide. type b t cells are implicated in autoimmune conditions and may break tolerance by escaping negative selection. here we show that salmonella differentially ...201323319341
intratumoral injection of attenuated salmonella vaccine can induce tumor microenvironmental shift from immune suppressive to immunogenic.attenuated salmonella vaccines show therapeutic anti-cancer effects, but the underlying mechanism has not been well investigated. in the current study, intratumoral (i.t.) injection of recombinant attenuated salmonella enterica serovar typhimurium vaccine (rasv) significantly inhibited her-2/neu-expressing tumor growth. although depletion of cd8(+) cells in rasv-treated mice significantly restored tumor growth, the induction of her-2/neu-specific cytotoxic t lymphocytes (ctls) was not well corre ...201323318147
characterization of an acid-inducible sulfatase in salmonella enterica serovar typhimurium.sulfatases of enteric bacteria can provide access to heavily sulfated mucosal glycans. in this study, we show that asla (stm0084) of salmonella enterica serovar typhimurium lt2 encodes a sulfatase that requires mildly acidic ph for its expression and activity. asla is not regulated by sulfur compounds or tyramine but requires the envz-ompr and phopq regulatory systems, which play an important role in pathogenesis.201323315743
molecular characterization of the inve regulator in the secretion of type iii secretion translocases in salmonella enterica serovar typhimurium.the type iii secretion systems (t3sss) are exploited by many gram-negative pathogenic bacteria to deliver a set of effector proteins into the host cytosol during cell entry. the t3ss of salmonella enterica serovar typhimurium is composed of more than 20 proteins that constitute the membrane-associated base, the needle and the tip complex at the distal end of the t3ss needle. membrane docking and piercing between the t3ss and host cells is followed by the secretion of effector proteins. therefore ...201323288540
human isolates of salmonella enterica serovar typhimurium from taiwan displayed significantly higher levels of antimicrobial resistance than those from denmark.salmonella enterica serovar typhimurium is a major zoonotic pathogen with a high prevalence of antimicrobial resistance. this pathogen can disseminate across borders and spread far distances via the food trade and international travel. in this study, we compared the genotypes and antimicrobial resistance of 378 s. typhimurium isolates collected in taiwan and denmark between 2009 and 2010. genotyping revealed that many s. typhimurium strains were concurrently circulating in taiwan, denmark and ot ...201323279815
exploring the immune response of porcine mesenteric lymph nodes to salmonella enterica serovar typhimurium: an analysis of transcriptional changes, morphological alterations and pathogen burden.infections caused by salmonella enterica serovar typhimurium (s. typhimurium) cause important economic problems in the swine industry and threaten the integrity of a safe and healthy food supply. controlling the prevalence of salmonella in pig production requires a thorough knowledge of the response processes that occurs in the gut associated immune tissues. to explore the in vivo porcine response to s. typhimurium, mln samples from four control pigs and twelve infected animals at 1, 2 and 6 day ...201323274115
salmonella infection in a remote, isolated wild pig population.although wild pig populations are known to sometimes be infected by salmonella, the situation in australia has received little attention and few population-based, planned studies have been conducted. understanding the distribution of salmonella infections within wild pig populations allows the potential hazard posed to co-grazing livestock to be assessed. we sampled a remote and isolated wild pig population in northwestern australia. faecal and mesenteric lymph node samples were collected from 6 ...201323266110
critical role of type i interferon-induced macrophage necroptosis during infection with salmonella enterica serovar typhimurium. 201323262973
intraspecies competition for niches in the distal gut dictate transmission during persistent salmonella infection.in order to be transmitted, a pathogen must first successfully colonize and multiply within a host. ecological principles can be applied to study host-pathogen interactions to predict transmission dynamics. little is known about the population biology of salmonella during persistent infection. to define salmonella enterica serovar typhimurium population structure in this context, 129svj mice were oral gavaged with a mixture of eight wild-type isogenic tagged salmonella (wits) strains. distinct s ...201425474319
identification of antigenic proteins of the nosocomial pathogen klebsiella pneumoniae.the continuous expansion of nosocomial infections around the globe has become a precarious situation. key challenges include mounting dissemination of multiple resistances to antibiotics, the easy transmission and the growing mortality rates of hospital-acquired bacterial diseases. thus, new ways to rapidly detect these infections are vital. consequently, researchers around the globe pursue innovative approaches for point-of-care devices. in many cases the specific interaction of an antigen and ...201425333280
salmonella enterica in the chicken: how it has helped our understanding of immunology in a non-biomedical model species.salmonella infection of the chicken is important both as a source of foodborne human salmonellosis and as a source of disease in the chicken itself. vaccination and other control strategies require an understanding of the immune response and as such have been important in understanding both mucosal immunity and more generally the response to bacterial infection. in this review, we discuss the contribution the study of avian salmonellosis has made to understanding innate immunity including the fu ...201425346731
spread and transmission of bacterial pathogens in experimental populations of the nematode caenorhabditis elegans.caenorhabditis elegans is frequently used as a model species for the study of bacterial virulence and innate immunity. in recent years, diverse mechanisms contributing to the nematode's immune response to bacterial infection have been discovered. yet despite growing interest in the biochemical and molecular basis of nematode-bacterium associations, many questions remain about their ecology. although recent studies have demonstrated that free-living nematodes could act as vectors of opportunistic ...201424973073
gastroenteritis due to typhoidal salmonella: a decade of observation at an urban and a rural diarrheal disease hospital in bangladesh.the study aimed to compare the socio-demographic, host and clinical characteristics, seasonality and antimicrobial susceptibility of typhoidal salmonella (salmonella enterica serovar typhi and paratyphi) (ts) with diarrhea between urban and rural bangladesh.201425098316
epidemiology of pathogenic enterobacteria in humans, livestock, and peridomestic rodents in rural madagascar.among the families of enteric bacteria are globally important diarrheal agents. despite their potential for zoonotic and environmental transmission, few studies have examined the epidemiology of these pathogens in rural systems characterized by extensive overlap among humans, domesticated and peridomestic animals. we investigated patterns of infection with enterotoxigenic escherichia coli, shigella spp., salmonella enterica, vibrio cholerae, and yersinia spp. (enterocolitica, and pseudotuberculo ...201424983990
the focal complex of epithelial cells provides a signalling platform for interleukin-8 induction in response to bacterial pathogens.bacterial pathogens can induce an inflammatory response from epithelial tissues due to secretion of the pro-inflammatory chemokine interleukin-8 (il-8). many bacterial pathogens manipulate components of the focal complex (fc) to induce signalling events in host cells. we examined the interaction of several bacterial pathogens with host cells, including campylobacter jejuni, to determine if the fc is required for induction of chemokine signalling in response to bacterial pathogens. our data indic ...201424779413
the evolutionary history and diagnostic utility of the crispr-cas system within salmonella enterica ssp. enterica.evolutionary studies of clustered regularly interspaced short palindromic repeats (crisprs) and their associated (cas) genes can provide insights into host-pathogen co-evolutionary dynamics and the frequency at which different genomic events (e.g., horizontal vs. vertical transmission) occur. within this study, we used whole genome sequence (wgs) data to determine the evolutionary history and genetic diversity of crispr loci and cas genes among a diverse set of 427 salmonella enterica ssp. enter ...201424765574
the arable ecosystem as battleground for emergence of new human pathogens.disease incidences related to escherichia coli and salmonella enterica infections by consumption of (fresh) vegetables, sprouts, and occasionally fruits made clear that these pathogens are not only transmitted to humans via the "classical" routes of meat, eggs, and dairy products, but also can be transmitted to humans via plants or products derived from plants. nowadays, it is of major concern that these human pathogens, especially the ones belonging to the taxonomical family of enterobacteriace ...201424688484
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