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lactic acid bacteria and bifidobacteria attenuate the proinflammatory response in intestinal epithelial cells induced by salmonella enterica serovar typhimurium.inflammation is a physiological response to infections and tissue injury; however, abnormal immune responses can give rise to chronic inflammation and contribute to disease progression. various dietary components, including probiotic lactic acid bacteria and prebiotics, have the potential to modulate intestinal inflammatory responses. one factor in particular, the chemokine interleukin-8 (il-8, cxcl-8), is one of the major mediators of the inflammatory response. the purpose of this study was to ...201223391223
evaluation of salmonella enterica serovar typhimurium ttss-2 deficient fur mutant as safe live-attenuated vaccine candidate for immunocompromised mice.salmonella enterica serovar typhimurium has been extensively exploited as live attenuated vaccines (lav) which generally confers better protection than killed or subunit vaccines. however, many lav are limited by their inherent ability to access systemic organs in many of the vaccinated hosts, especially those which are immunocompromised. we evaluated the efficacy of a live-attenuated spi2-deficient (δssav) s. typhimurium vaccine candidate (mt13) that additionally devoids the ferric uptake regul ...201223284865
salmonella typhimurium's transthyretin-like protein is a host-specific factor important in fecal survival in chickens.the transthyretin-like protein (tlp) from salmonella enterica subspecies i is a periplasmic protein with high level structural similarity to a protein found in mammals and fish. in humans, the protein homologue, transthyretin, binds and carries retinol and thyroxine, and a series of other, unrelated aromatic compounds. here we show that the amino acid sequence of the tlp from different species, subspecies and serovars of the salmonella genus is highly conserved and demonstrate that the tlp gene ...201223284609
characterization of citrobacter sp. line 328 as a source of vi for a vi-crm(197) glycoconjugate vaccine against salmonella typhi.salmonella enterica serovar typhi is the causative agent of typhoid fever with over 22 million cases and over 200,000 deaths reported annually. a vaccine is much needed for use in young children and the novartis vaccines institute for global health (nvgh) is developing a conjugate vaccine which targets s. typhi vi capsular polysaccharide.201223277501
optimized microbial dna extraction from diarrheic stools.the detection of enteropathogens in stool specimens increasingly relies on the detection of specific nucleic acid sequences. we observed that such detection was hampered in diarrheic stool specimens and we set-up an improved protocol combining lyophilization of stools prior to a semi-automated dna extraction.201223273000
azithromycin and ciprofloxacin resistance in salmonella bloodstream infections in cambodian adults.salmonella enterica is a frequent cause of bloodstream infection (bsi) in asia but few data are available from cambodia. we describe salmonella bsi isolates recovered from patients presenting at sihanouk hospital centre of hope, phnom penh, cambodia (july 2007-december 2010).201223272255
sesbania grandiflora leaf extract mediated green synthesis of antibacterial silver nanoparticles against selected human pathogens.simple, effective and rapid approach for the green synthesis of silver nanoparticles (agnps) using leaf extract of sesbania grandiflora and their in vitro antibacterial activity against selected human pathogens has been demonstrated in the study. various instrumental techniques were adopted to characterize the synthesized agnps viz. uv-vis, ftir, xrd, tem, edx and afm. surface plasmon spectra for agnps are centered at 422 nm with dark brown color. the synthesized agnps were found to be spherical ...201223270884
spontaneous non-rdar mutations increase fitness of salmonella in plants.proliferation of human enteric pathogens within alternate hosts, like plants, leads to temporal changes in gene expression and also selects for the phenotypic variants of the enterics that are presumed to be more fit within plants. human enteric pathogens recovered from produce-borne outbreaks exhibit peculiar phenotypes, for example many of them do not display the rdar (red dry and rough) phenotype. the non-rdar phenotype results from mutations in cellulose and/or curli synthesis or regulation. ...201223760832
root internalization, transport and in-planta survival of salmonella enterica serovar newport in sweet basil.it is now acknowledged that food-borne pathogens present in the irrigation water or soil can become associated with crop plants in the field, penetrate internal plant tissues via the root, translocate and survive inside plants. only little information is available concerning interaction between enteric pathogens and plants. the present study evaluated the potential for contamination of the aromatic plant, sweet basil during cultivation, by salmonella enterica serovar newport. root internalizatio ...201223757144
evaluation of the strain variability of salmonella enterica acid and heat resistance.the inherent acid and heat resistances of 60 salmonella enterica strains were assessed in tryptone soy broth without dextrose acidified to ph 3.0 or heated at 57 °c. a total of 360 inactivation curves were generated. regarding the acid challenge experiments, the inactivation rate (kacid), estimated using the log-linear model, ranged from 0.47 to 3.25 h(-1). a log-linear model with a "survival tail" was used to describe the thermal inactivation of the strains, and the estimated inactivation rate ...201223541192
inactivation of salmonella enterica serovar typhimurium and escherichia coli o157:h7 in peanut butter cracker sandwiches by radio-frequency heating.a multistate outbreak of salmonella enterica serovar typhimurium recently occurred in the usa, which was traced back to various food products made with contaminated peanut butter. this study was conducted to investigate the efficacy of radio-frequency (rf) heating to inactivate s. typhimurium and escherichia coli o157:h7 in peanut butter cracker sandwiches using creamy and chunky commercial peanut butter and to determine the effect on quality by measuring color changes and sensory evaluation. sa ...201223498191
salmonella enterica serovar typhi in breast abscess: a case report. 201223455830
Description of a 2,683-Base-Pair Plasmid Containing qnrD in Two Providencia rettgeri Isolates.qnr genes are plasmid-mediated quinolone resistance genes mainly harbored on large conjugative multiresistant plasmids. The qnrD gene was recently observed in Salmonella enterica on a small nonconjugative plasmid (p2007057). We describe two strains of Providencia rettgeri harboring qnrD on nonconjugative plasmids. The plasmids were 99% identical, with 2,683 bp and four open reading frames, including qnrD, but exhibited only 53% identity with the plasmid found in S. enterica.201221986831
Breast Abscess in a Man Due to Salmonella enterica Serotype Enteritidis.Nontyphoidal salmonellae can cause breast infection only exceptionally. A case of breast abscess in a 70-year-old man due to Salmonella enterica serotype Enteritidis (Salmonella Enteritidis) is reported. The infection was successfully treated with a combination of surgical and antibiotic treatment.201222031702
expansion of paneth cell population in response to enteric salmonella enterica serovar typhimurium infection.paneth cells residing at the base of the small intestinal crypts contribute to the mucosal intestinal first line defense by secreting granules filled with antimicrobial polypeptides including lysozyme. these cells derive from the columnar intestinal stem cell located at position 0 and the transit amplifying cell located at position +4 in the crypts. we have previously shown that salmonella enterica serovar typhimurium (st), a leading cause of gastrointestinal infections in humans, effects an ove ...201222006567
salmonella enterica as a vaccine carrier.salmonella enterica is an invasive, facultative intracellular gastrointestinal pathogen causing human diseases such as gastroenteritis and typhoid fever. virulence-attenuated strains of this pathogen have interesting capacities for the generation of live vaccines. attenuated live typhoidal and nontyphoidal salmonella strains can be used for vaccination against salmonella infections and to target tumor tissue. such strains may also serve as live carriers for the development of vaccination strateg ...201222191450
Thiosulfate Reduction in Salmonella enterica Is Driven by the Proton Motive Force.Thiosulfate respiration in Salmonella enterica serovar Typhimurium is catalyzed by the membrane-bound enzyme thiosulfate reductase. Experiments with quinone biosynthesis mutants show that menaquinol is the sole electron donor to thiosulfate reductase. However, the reduction of thiosulfate by menaquinol is highly endergonic under standard conditions (?E°' = -328 mV). Thiosulfate reductase activity was found to depend on the proton motive force (PMF) across the cytoplasmic membrane. A structural m ...201222081391
Detecting non-typhoid Salmonella in humans by ELISAs: a literature review.Non-typhoid salmonellosis is one of the most common causes of foodborne illness throughout the world. Serological methods for the diagnosis of Salmonella infections vary widely and the most commonly used test is limited by high running costs as well as low sensitivity and specificity. Fast and reliable immunoassays which detect subunit antigens for Salmonella enterica subsp. enterica serovar Typhi are commercially available but at present there is no international consensus on similar tests for ...201222034162
characterization and comparative genomic analysis of a novel bacteriophage, sfp10, simultaneously inhibiting both salmonella enterica and escherichia coli o157:h7.salmonella enterica and escherichia coli o157:h7 are major food-borne pathogens causing serious illness. phage sfp10, which revealed effective infection of both s. enterica and e. coli o157:h7, was isolated and characterized. sfp10 contains a 158-kb double-stranded dna genome belonging to the vi01 phage-like family myoviridae. in vitro adsorption assays showed that the adsorption constant rates to both salmonella enterica serovar typhimurium and e. coli o157:h7 were 2.50 × 10(-8) ml/min and 1.91 ...201222020516
treatment of raw poultry with nonthermal dielectric barrier discharge plasma to reduce campylobacter jejuni and salmonella enterica.nonthermal plasma has been shown to be effective in reducing pathogens on the surface of a range of fresh produce products. the research presented here investigated the effectiveness of nonthermal dielectric barrier discharge plasma on salmonella enterica and campylobacter jejuni inoculated onto the surface of boneless skinless chicken breast and chicken thigh with skin. chicken samples were inoculated with antibiotic-resistant strains of s. enterica and c. jejuni at levels of 10(1) to 10(4) cf ...201222221351
evaluation of salmonella enterica type iii secretion system effector proteins as carriers for heterologous vaccine antigens.live attenuated strains of salmonella enterica have a high potential as carriers of recombinant vaccines. the type iii secretion system (t3ss)-dependent translocation of s. enterica can be deployed for delivery of heterologous antigens to antigen-presenting cells. here we investigated the efficacy of various effector proteins of the salmonella pathogenicity island (spi2)-encoded t3ss for the translocation of model antigens and elicitation of immune responses. the spi2-t3ss effector proteins sifa ...201222252866
nlrc4 inflammasomes in dendritic cells regulate noncognate effector function by memory cd8(+) t cells.memory t cells exert antigen-independent effector functions, but how these responses are regulated is unclear. we discovered an in vivo link between flagellin-induced nlrc4 inflammasome activation in splenic dendritic cells (dcs) and host protective interferon-γ (ifn-γ) secretion by noncognate memory cd8(+) t cells, which could be activated by salmonella enterica serovar typhimurium, yersinia pseudotuberculosis and pseudomonas aeruginosa. we show that cd8α(+) dcs were particularly efficient at s ...201222231517
the architecture and ppgpp-dependent expression of the primary transcriptome of salmonella typhimurium during invasion gene expression.abstract: background: invasion of intestinal epithelial cells by salmonella enterica serovar typhimurium (s. typhimurium) requires expression of the extracellular virulence gene expression programme (stex), activation of which is dependent on the signalling molecule guanosine tetraphosphate (ppgpp). recently, next-generation transcriptomics (rna-seq) has revealed the unexpected complexity of bacterial transcriptomes and in this report we use differential rna sequencing (drna-seq) to define the ...201222251276
antimicrobial activity of different copper alloy surfaces against copper resistant and sensitive salmonella enterica.copper has shown antibacterial effects against foodborne pathogens. the objective of this study was to evaluate the antibacterial activity of copper surfaces on copper resistant and sensitive strains of salmonella enterica. six different copper alloy coupons (60-99.9% copper) were tested along with stainless steel as the control. the coupons were surface inoculated with either s. enteritidis or one of the 3 copper resistant strains, s. typhimurium s9, s19 and s20; stored under various incubation ...201222265316
transcriptome sequencing of salmonella enterica serovar enteritidis under desiccation and starvation stress in peanut oil.it is well recognized that salmonella can survive long-term starvation and desiccation stresses and contaminate foods that have intermediate to low water activities; however, little is known about the specific molecular mechanisms underlying its survival and persistence in low water activity foods. in this study, we used the rna-seq approach to compare the transcriptomes (27-33 million 36-bp reads per sample) of a salmonella enterica subsp. enteric serovar enteritidis strain atcc baa-1045 after ...201222265317
inhibition of bacterial carbonic anhydrases and zinc proteases: from orphantargets to innovative new antibiotic drugs.zinc-containing enzymes, such as carbonic anhydrases (cas) and metalloproteases (mps) play critical functions in bacteria, being involved in various steps of their life cycle, which are important for survival, colonization, acquisition of nutrients for growth and proliferation, facilitation of dissemination, invasion and pathogenicity. the development of resistance to many classes of clinically used antibiotics emphasizes the need of new antibacterial drug targets to be explored. there is a weal ...201222214451
the antibiotic resistance characteristics of non-typhoidal salmonella enterica isolated from food-producing animals, retail meat and humans in south east asia.antimicrobial resistance is a global problem. it is most prevalent in developing countries where infectious diseases remain common, the use of antibiotics in humans and animals is widespread, and the replacement of older antibiotics with new generation antibiotics is not easy due to the high cost. information on antibiotic resistance phenotypes and genotypes of salmonella spp. in food animals and humans in different countries and geographic regions is necessary to combat the spread of resistance ...201222265849
recombinant antibodies encoded by ighv1-69 react with pul32, a phosphoprotein of cytomegalovirus and b-cell superantigen.leukemia cells from patients with chronic lymphocytic leukemia (cll) express a highly restricted immunoglobulin heavy variable chain (ighv) repertoire, which suggests that a limited set of antigens reacts with leukemic cells. here, we evaluated the reactivity of a panel of different cll recombinant antibodies (rabs) encoded by the most commonly expressed ighv genes with a panel of selected viral and bacterial pathogens. six different cll rabs encoded by ighv1-69 or ighv3-21, but not a cll rab en ...201222234695
general stress sigma factor rpos influences time required to enter the viable but non-culturable state in salmonella enterica.in stressful conditions, bacteria enter into the viable but non-culturable (vbnc) state; in this state, they are alive but fail to grow on conventional media on which they normally grow and develop into colonies. the molecular basis underlying this state is unknown. we investigated the role of the alternative sigma factor rpos (σ(38) ) in the vbnc induction using salmonella dublin, salmonella oranienburg and salmonella typhimurium lt2. vbnc was induced by osmotic stress in lt2 and oranienburg. d ...201222256797
bio-capture of s. typhimurium from surface water by aptamer for culture-free quantification.in this study, a dna aptamer was used to bio-capture salmonella enterica serovar typhimurium from surface water collected from highly endemic zone prior to culture-free detection through molecular-beacon based real-time pcr assay targeting inva gene. the assay could detect s. typhimurium cells (1cfu/pcr or 100cfu/ml) selectively captured by serovar specific dna aptamer. the observations indicate that all the water samples (n=40) collected from the river gomti were contaminated by s. typhimurium ...201222226327
electrospun poly(l-lactic acid)-co-poly(ɛ-caprolactone) nanofibres containing silver nanoparticles for skin-tissue engineering.silver nanoparticles (agnps) and silver ions (ag(+)) show growth-inhibitory activity against microorganisms and have been used for decades as antibacterial agents in various fields. to fabricate a nanofibrous scaffold which is antibacterial against bacteria and non-toxic to cells, we electrospun composite poly(l-lactic acid)-co-poly(ɛ-caprolactone) nanofibres containing silver nanoparticles (pllcl-agnps) with different concentrations (0.25, 0.50 and 0.75 wt%) of silver nitrate (agno(3)) in pllcl ...201222244047
immunological characterization of a gida mutant strain of salmonella for potential use in a live-attenuated vaccine.salmonella is often associated with gastrointestinal disease outbreaks in humans throughout the world due to the consumption of contaminated food. our previous studies have shown that deletion of glucose-inhibited division gene (gida) significantly attenuated salmonella enterica serovar typhimurium (stm) virulence in both in vitro and in vivo models of infection. most importantly, immunization with the gida mutant protected mice from a lethal dose challenge of wild-type stm. in this study, we fu ...201223194372
natural lysogenization and transduction in salmonella enterica serovar choleraesuis by bacteriophage p1.it has been reported that bacteriophage p1 injects dna into serovar choleraesuis without evidence of productive infection. however, we found that p1 generates progeny and is capable of transduction in serovar choleraesuis. this is not the case with other serovars of salmonella enterica we tested. therefore, p1 could play a role in serovar choleraesuis evolution and contribute to its genetic manipulation and analysis.201222995628
bacterial pathogens commandeer rab gtpases to establish intracellular niches.intracellular bacterial pathogens deploy virulence factors termed effectors to inhibit degradation by host cells and to establish intracellular niches where growth and differentiation take place. here, we describe mechanisms by which human bacterial pathogens (including chlamydiae; coxiella burnetii; helicobacter pylori; legionella pneumophila; listeria monocytogenes; mycobacteria; pseudomonas aeruginosa, salmonella enterica) modulate endocytic and exocytic rab gtpases in order to thrive in host ...201222901006
rapid discrimination of salmonella enterica serovar typhi from other serovars by maldi-tof mass spectrometry.systemic infections caused by salmonella enterica are an ongoing public health problem especially in sub-saharan africa. essentially typhoid fever is associated with high mortality particularly because of the increasing prevalence of multidrug-resistant strains. thus, a rapid blood-culture based bacterial species diagnosis including an immediate sub-differentiation of the various serovars is mandatory. at present, maldi-tof based intact cell mass spectrometry (icms) advances to a widely used rou ...201222768195
salmonella promotes asc oligomerization-dependent caspase-1 activation.innate immune cells sense and respond to the cytoplasmic infection of bacterial pathogens through nlrp3, nlrc4 or aim2 inflammasome depending on the unique molecular pattern of invading pathogens. the infection of flagellin- or type iii secretion system (t3ss)-containing gram-negative bacteria such as salmonella enterica serovar typhimurium (s. typhimurium) or pseudomonas aeruginosa (p. aeruginosa) triggers nlrc4-dependent caspase-1 activation leading to the secretion of proinflammatory cytokine ...201223396959
interplay between the qsec and qsee bacterial adrenergic sensor kinases in salmonella enterica serovar typhimurium pathogenesis.the bacterial adrenergic sensor kinases qsec and qsee respond to epinephrine and/or norepinephrine to initiate a complex phosphorelay regulatory cascade that modulates virulence gene expression in several pathogens. we have previously shown that qsec activates virulence gene expression in salmonella enterica serovar typhimurium. here we report the role of qsee in s. typhimurium pathogenesis as well as the interplay between these two histidine sensor kinases in gene regulation. an s. typhimurium ...201223027532
assessment of whole-genome mapping in a well-defined outbreak of salmonella enterica serotype saintpaul.we investigated the use of whole-genome mapping and pulsed-field gel electrophoresis (pfge) with isolates from an outbreak of salmonella enterica serotype saintpaul. pfge and whole-genome mapping were concordant with 22 of 23 isolates. whole-genome mapping is a viable alternative tool for the epidemiological analysis of salmonella food-borne disease investigations.201222718933
foxp3(+) regulatory t cells, immune stimulation and host defence against infection.the immune system is intricately regulated allowing potent effectors to expand and become rapidly mobilized after infection, while simultaneously silencing potentially detrimental responses that averts immune-mediated damage to host tissues. this relies in large part on the delicate interplay between immune suppressive regulatory cd4(+) t (treg) cells and immune effectors that without active suppression by treg cells cause systemic and organ-specific autoimmunity. although these beneficial roles ...201222211994
polyamines are required for virulence in salmonella enterica serovar typhimurium.sensing and responding to environmental cues is a fundamental characteristic of bacterial physiology and virulence. here we identify polyamines as novel environmental signals essential for virulence of salmonella enterica serovar typhimurium, a major intracellular pathogen and a model organism for studying typhoid fever. central to its virulence are two major virulence loci salmonella pathogenicity island 1 and 2 (spi1 and spi2). spi1 promotes invasion of epithelial cells, whereas spi2 enables s ...201222558361
novel genomic tools for specific and real-time detection of biothreat and frequently encountered foodborne pathogens.the bacterial genera escherichia, salmonella, shigella, vibrio, yersinia, and francisella include important food safety and biothreat agents. by extensive mining of the whole genome and protein databases of diverse, closely and distantly related bacterial species and strains, we have identified novel genome regions, which we utilized to develop a rapid detection platform for these pathogens. the specific genomic targets we have identified to design the primers in francisella tularensis subsp. tu ...201222488053
caspase-1 activity is required to bypass macrophage apoptosis upon salmonella infection.here we report awp28, an activity-based probe that can be used to biochemically monitor caspase-1 activation in response to proinflammatory stimuli. using awp28, we show that apoptosis is triggered upon salmonella enterica var. typhimurium infection in primary mouse bone marrow macrophages lacking caspase-1. furthermore, we report that upon salmonella infection, inflammasome-mediated caspase-1 activity is required to bypass apoptosis in favor of proinflammatory pyroptotic cell death.201222797665
isolation and preliminary characterization of amino acid substitution mutations that increase the activity of the osmoregulated prop protein of salmonella enterica serovar typhimurium.in enterobacteriaceae, the prop protein, which takes up proline and glycine betaine, is subject to a post-translational control mechanism that increases its activity at high osmolarity. in order to investigate the osmoregulatory mechanism of the salmonella enterica prop, we devised a positive selection for mutations that conferred increased activity on this protein at low osmolarity. the selection involved the isolation of mutations in a proline auxotroph that resulted in increased accumulation ...201222360681
isolation of a paenibacillus sp. strain and structural elucidation of its broad-spectrum lipopeptide antibiotic.this research was initiated to search for novel antimicrobial compounds produced by food or environmental microorganisms. a new bacterial strain, designated osy-se, which produces a unique and potent antimicrobial agent was isolated from soil. the isolate was identified as a paenibacillus sp. through cultural, biochemical, and genetic analyses. an antimicrobial compound was extracted from paenibacillus osy-se with acetonitrile and purified using liquid chromatography. after analyses by mass spec ...201222367082
differential biofilm formation and chemical disinfection resistance of sessile cells of listeria monocytogenes strains under monospecies and dual-species (with salmonella enterica) conditions.this study aimed to investigate the possible influence of bacterial intra- and interspecies interactions on the ability of listeria monocytogenes and salmonella enterica to develop mixed-culture biofilms on an abiotic substratum, as well as on the subsequent resistance of sessile cells to chemical disinfection. initially, three strains from each species were selected and left to attach and form biofilms on stainless steel (ss) coupons incubated at 15°c for 144 h, in periodically renewable trypto ...201222307304
variable carbon catabolism among salmonella enterica serovar typhi isolates.salmonella enterica serovar typhi (s. typhi) is strictly a human intracellular pathogen. it causes acute systemic (typhoid fever) and chronic infections that result in long-term asymptomatic human carriage. s. typhi displays diverse disease manifestations in human infection and exhibits high clonality. the principal factors underlying the unique lifestyle of s. typhi in its human host during acute and chronic infections remain largely unknown and are therefore the main objective of this study.201222662115
characterization of modular bacteriophage endolysins from myoviridae phages obp, 201φ2-1 and pvp-se1.peptidoglycan lytic enzymes (endolysins) induce bacterial host cell lysis in the late phase of the lytic bacteriophage replication cycle. endolysins obpgp279 (from pseudomonas fluorescens phage obp), pvp-se1gp146 (salmonella enterica serovar enteritidis phage pvp-se1) and 201φ2-1gp229 (pseudomonas chlororaphis phage 201φ2-1) all possess a modular structure with an n-terminal cell wall binding domain and a c-terminal catalytic domain, a unique property for endolysins with a gram-negative backgrou ...201222615864
enhanced inactivation of salmonella and pseudomonas biofilms on stainless steel by use of t-128, a fresh-produce washing aid, in chlorinated wash solutions.the effect of the washing aid t-128 (generally recognized as safe [gras] formulation, composed mainly of phosphoric acid and propylene glycol) on inactivation of salmonella and pseudomonas populations in biofilms on stainless steel was evaluated under conditions of increasing organic matter loads in chlorinated wash solutions dominated by hypochlorous acid. biofilms were formed statically on stainless steel coupons suspended in 2% lettuce extract after inoculation with salmonella enterica serova ...201222752180
phosphorothioate dna as an antioxidant in bacteria.diverse bacteria contain dna with sulfur incorporated stereo-specifically into their dna backbone at specific sequences (phosphorothioation). we found that in vitro oxidation of phosphorothioate (pt) dna by hydrogen peroxide (h(2)o(2)) or peracetic acid has two possible outcomes: dna backbone cleavage or sulfur removal resulting in restoration of normal dna backbone. the physiological relevance of this redox reaction was investigated by challenging pt dna hosting salmonella enterica cells using ...201222772986
requirement of siderophore biosynthesis for plant colonization by salmonella enterica.contaminated fresh produce has become the number one vector of nontyphoidal salmonellosis to humans. however, salmonella enterica genes essential for the life cycle of the organism outside the mammalian host are for the most part unknown. screening deletion mutants led to the discovery that an aroa mutant had a significant root colonization defect due to a failure to replicate. aroa is part of the chorismic acid biosynthesis pathway, a central metabolic node involved in aromatic amino acid and s ...201222522683
engineering of acetyl-coa metabolism for the improved production of polyhydroxybutyrate in saccharomyces cerevisiae.through metabolic engineering microorganisms can be engineered to produce new products and further produce these with higher yield and productivities. here, we expressed the bacterial polyhydroxybutyrate (phb) pathway in the yeast saccharomyces cerevisiae and we further evaluated the effect of engineering the formation of acetyl coenzyme a (acetyl-coa), an intermediate of the central carbon metabolism and precursor of the phb pathway, on heterologous phb production by yeast. we engineered the ac ...201223009357
srfj, a salmonella type iii secretion system effector regulated by phop, rcsb, and iolr.virulence-related type iii secretion systems are present in many gram-negative bacterial pathogens. these complex devices translocate proteins, called effectors, from the bacterium into the eukaryotic host cell. here, we identify the product of srfj, a salmonella enterica serovar typhimurium gene regulated by ssrb, as a new substrate of the type iii secretion system encoded by salmonella pathogenicity island 2. the n-terminal 20-amino-acid segment of srfj was recognized as a functional secretion ...201222661691
functional and computational analysis of amino acid patterns predictive of type iii secretion system substrates in pseudomonas syringae.bacterial type iii secretion systems (t3sss) deliver proteins called effectors into eukaryotic cells. although n-terminal amino acid sequences are required for translocation, the mechanism of substrate recognition by the t3ss is unknown. almost all actively deployed t3ss substrates in the plant pathogen pseudomonas syringae pathovar tomato strain dc3000 possess characteristic patterns, including (i) greater than 10% serine within the first 50 amino acids, (ii) an aliphatic residue or proline at ...201222558318
type vi secretion system-associated gene clusters contribute to pathogenesis of salmonella enterica serovar typhimurium.the enteropathogen salmonella enterica serovar typhimurium employs a suite of tightly regulated virulence factors within the intracellular compartment of phagocytic host cells resulting in systemic dissemination in mice. a type vi secretion system (t6ss) within salmonella pathogenicity island 6 (spi-6) has been implicated in this process; however, the regulatory inputs and the roles of noncore genes in this system are not well understood. here we describe four clusters of noncore t6ss genes in s ...201222493086
a glycine betaine importer limits salmonella stress resistance and tissue colonization by reducing trehalose production.mechanisms by which salmonella establish chronic infections are not well understood. microbes respond to stress by importing or producing compatible solutes, small molecules that stabilize proteins and lipids. the salmonella locus opuabcd (also called opuc) encodes a predicted importer of the compatible solute glycine betaine. under stress conditions, if glycine betaine cannot be imported, salmonella enterica produce the disaccharide trehalose, a highly effective compatible solute. we demonstrat ...201222375627
identification of a third osmoprotectant transport system, the osmu system, in salmonella enterica.the growth of salmonella enterica serovar typhimurium mutants lacking the prop and prou osmoprotectant transport systems is stimulated by glycine betaine in high-osmolarity media, suggesting that this organism has an additional osmoprotectant transport system. bioinformatic analysis revealed that the genome of this organism contains a hitherto-unidentified operon, designated osmu, consisting of four genes whose products show high similarity to abc-type transport systems for osmoprotectants in ot ...201222609924
functional dissection of ssef, a membrane-integral effector protein of intracellular salmonella enterica.during intracellular life, the bacterial pathogen salmonella enterica translocates a complex cocktail of effector proteins by means of the spi2-encoded type iii secretions system. the effectors jointly modify the endosomal system and vesicular transport in host cells. ssef and sseg are two effectors encoded by genes within salmonella pathogenicity island 2 and both effector associate with endosomal membranes and microtubules and are involved in the formation of salmonella-induced filaments. our ...201222529968
Phagocytosis and killing of salmonella by 7-hydroxycoumarin activated macrophages.Coumarin and its derivatives have potent immunomodulatory activities. Here we describe the parameters of the protective effect of 7-hydroxycoumarin (7-OHC) in experimental Salmonella enterica Serovar Typhimurium infection in mice. The protective effect depended on the duration of treatment reaching its maximum after 10 days of pretreatment and lasted for at least 15 days after its end. Electron microscopy studies revealed that 7-OHC induced ultrastructural changes in macrophages consistent with ...201222007641
The C-terminal domain of the Salmonella enterica WbaP (UDP-galactose:Und-P galactose-1-phosphate transferase) is sufficient for catalytic activity and specificity for undecaprenyl monophosphate.Two families of membrane enzymes catalyze the initiation of the synthesis of O-antigen lipopolysaccharide. The Salmonella enterica Typhimurium WbaP is a prototypic member of one of these families. We report here the purification and biochemical characterization of the WbaP C-terminal (WbaP(CT)) domain harboring one putative transmembrane helix and a large cytoplasmic tail. An N-terminal thioredoxin fusion greatly improved solubility and stability of WbaP(CT) allowing us to obtain highly purified ...201221856724
Molecular characterization of strains of fluoroquinolone-resistant Salmonella enterica serovar Schwarzengrund carrying multidrug resistance isolated from imported foods.Objectives To determine the fluoroquinolone resistance determinants in Salmonella enterica serovar Schwarzengrund from imported foods. Methods Antibiotic susceptibility of Salmonella Schwarzengrund to 16 antibiotics was examined using disc agar diffusion and Etest. Quinolone resistance determinants were examined by sequence analysis of gyrA, gyrB, parC and parE, PCR amplification of qnrA, qnrB and qnrS, and expression of acrB, ramA, marA, soxS and rob using quantitative RT-PCR. The contribution ...201222010209
A single method for recovery and concentration of enteric viruses and bacteria from fresh-cut vegetables.Fresh-cut vegetables are prone to be contaminated with foodborne pathogens during growth, harvest, transport and further processing and handling. As most of these products are generally eaten raw or mildly treated, there is an increase in the number of outbreaks caused by viruses and bacteria associated with fresh vegetables. Foodborne pathogens are usually present at very low levels and have to be concentrated (i.e. viruses) or enriched (i.e. bacteria) to enhance their detection. With this aim, ...201222036077
Resolving the contributions of the membrane-bound and periplasmic nitrate reductase systems to nitric oxide and nitrous oxide production in Salmonella enterica serovar Typhimurium.The production of cytotoxic nitric oxide (NO) and conversion into the neuropharmacological agent and potent greenhouse gas nitrous oxide (N2O) is linked with anoxic nitrate catabolism by Salmonella enterica serovar Typhimurium. Salmonella can synthesize two types of nitrate reductase: a membrane-bound form (Nar) and a periplasmic form (Nap). Nitrate catabolism was studied under nitrate-rich and nitrate-limited conditions in chemostat cultures following transition from oxic to anoxic conditions. ...201222039967
tn1548-associated arma is co-located with qnrb2, aac(6')-ib-cr and blactx-m-3 on an incfii plasmid in a salmonella enterica subsp. enterica serovar paratyphi b strain isolated from chickens in china. 201221965429
transfer of foodborne pathogenic bacteria to non-inoculated beef fillets through meat mincing machine.the aim of this study was to evaluate the transfer of pathogens population to non-inoculated beef fillets through meat mincing machine. in this regard, cocktails of mixed strain cultures of each listeria monocytogenes, salmonella enterica ser. typhimurium and escherichia coli o157:h7 were used for the inoculation of beef fillets. three different initial inoculum sizes (3, 5, or 7 log cfu/g) were tested. the inoculated beef fillets passed through meat mincing machine and then, six non-inoculated ...201222119672
Classification of Salmonella enterica serotypes from Australian poultry using repetitive sequence-based PCR.Aims: To evaluate a semi-automated repetitive extragenic palindromic sequence-based PCR (rep-PCR) system for the classification of Salmonella serotypes from Australian poultry. Methods and Results: Using a DNA fingerprint library within the DiversiLab(®) System, four separate databases were constructed (serogroup B, C, E and Other). These databases contained 483 serologically confirmed (reference laboratory) Salmonella isolates. A blinded set of Salmonella cultures (n = 155) were typed by rep ...201221981579
reductions of salmonella enterica on chicken breast by thymol, acetic acid, sodium dodecyl sulfate or hydrogen peroxide combinations as compared to chlorine wash.poultry products are important vehicles for salmonella transmission to humans and have been incriminated in several salmonella outbreaks. thymol (thy) from thyme oil has wide inhibitory effects against foodborne pathogens including salmonella, and has shown great potential as a natural alternative to chlorine. in order to improve the cost-effectiveness of thymol-based washing solutions, formulas of thy with combination of organic acid or surfactant were developed and their efficacies to reduce s ...201222030209
First multi-epitope subunit vaccine against extraintestinal pathogenic Escherichia coli delivered by a bacterial type-3 secretion system (T3SS).Infections due to extraintestinal pathogenic E. coli (ExPEC) are very common in humans as well as in animals. In humans ExPEC infections include urinary tract infections (UTI), septicemia, and wound infections, which result in significant morbidity, mortality, and substantial healthcare costs. In view of the increasing number of ExPEC infections caused by more and more resistant strains, effective prevention would be desirable. Given the rising treatment costs, a vaccine may be cost-effective in ...201222000741
complete genome sequence of salmonella enterica serovar typhimurium bacteriophage spn1s.to understand the interaction between the host of pathogenic salmonella enterica serovar typhimurium and its bacteriophage, we isolated the bacteriophage spn1s. it is a lysogenic phage in the podoviridae family and uses the o-antigen of lipopolysaccharides (lps) as a host receptor. comparative genomic analysis of phage spn1s and the s. enterica serovar anatum-specific phage ε15 revealed different host specificities, probably due to the low homology of host specificity-related genes. here we repo ...201222205721
Composition and antibacterial activity of essential oil from Scutellaria grossa Wall ex Benth.The chemical composition of the steam volatile oil of the whole aerial part of Scutellaria grossa Wall ex Benth. (Lamiaceae), obtained by steam distillation, has been analysed by capillary GC and GC-MS. The oil was found to be rich in oxygenated monoterpenes (88.6%). A total of 50 constituents were identified, representing 94.4% of the total oil composition. Linalool (37.0%) and 1-octen-3-ol (32.0%) were found to be the principal constituents. The antibacterial activity of the oil was determined ...201222060314
Immunochemical studies of Salmonella Dakar and Salmonella Telaviv O-antigens (serogroup O:28).Salmonella Dakar and Salmonella Telaviv bacteria belong to serogroup O:28, which represents 107 serovars and possesses only the epitope O28. Salmonella Telaviv has the subfactors O28(1) and O28(2) , whereas S. Dakar has O28(1) and O28(3) . So far, only limited serological and immunological information for this serogroup is available in the literature. Knowledge of the structures of their O-polysaccharides and the immunochemical investigations performed in this work allowed to reveal the nature ...201222092663
typhoid fever: "you can't hit what you can't see"the host restricts dissemination of invasive enteric pathogens, such as non-typhoidal salmonella serovars, by mounting acute inflammatory responses characterized by the recruitment of neutrophils. however, some enteric pathogens, such as salmonella enterica serovar typhi (s. typhi), can bypass these defenses and cause an invasive bloodstream infection known as typhoid fever. recent studies on virulence mechanisms of s. typhi suggest that tight regulation of virulence gene expression during the t ...201222156762
gaussia princeps luciferase as a reporter for transcriptional activity, protein secretion, and protein-protein interactions in salmonella enterica serovar typhimurium.gaussia princeps luciferase (gluc) is widely used as a reporter in eukaryotes, but data about its applicability in bacteria are very limited. here we show that a codon-optimized gluc gene can be efficiently expressed in salmonella enterica serovar typhimurium. to test different gluc variants as transcriptional reporters, we used the siia promoter of salmonella pathogenicity island 4 (spi-4) driving expression of either an episomal or a chromosomally integrated gluc gene. most reliable results we ...201222020521
Genetic response of Salmonella enterica serotype Enteritidis to thioridazine rendering the organism resistant to the agent.Thioridazine (TZ)-induced accumulation of the universal efflux pump substrate ethidium bromide and its subsequent efflux by Salmonella strains with various degrees of overexpressed efflux pumps takes place automatically at pH 7.4, is independent of a metabolic source, is not affected by a proton ionophore and is precluded by palmitic acid. Salmonella enterica serotype Enteritidis cultured in medium containing increasing concentrations of TZ does not grow during the first 6-8h, after which time i ...201221982147
enterobacterial common antigen mutants of salmonella enterica serovar typhimurium establish a persistent infection and provide protection against subsequent lethal challenge.infection with salmonella spp. is a significant source of disease globally. a substantial proportion of these infections are caused by salmonella enterica serovar typhimurium. here, we characterize the role of the enterobacterial common antigen (eca), a surface glycolipid ubiquitous among enteric bacteria, in s. typhimurium pathogenesis. construction of a defined mutation in the udp-n-acetylglucosamine-1-phosphate transferase gene, weca, in two clinically relevant strains of s. typhimurium, tml ...201222025511
competition and resilience between founder and introduced bacteria in the caenorhabditis elegans gut.the microbial communities that reside within the intestinal tract in vertebrates are complex and dynamic. in this report, we establish the utility of c. elegans as a model system for identifying the factors that contribute to bacterial persistence and for host control of gut luminal populations. we found that for n2 worms grown on mixed lawns of bacteria, salmonella substantially out-competed e. coli even when e. coli was initially present at 100-fold higher concentrations. to address whether in ...201122184417
in vivo expression of salmonella enterica serotype typhi genes in the blood of patients with typhoid fever in bangladesh.salmonella enterica serotype typhi is the cause of typhoid fever. it is a human-restricted pathogen, and few data exist on s. typhi gene expression in humans.201122180799
The TCA cycle is not required for selection or survival of multidrug-resistant Salmonella.OBJECTIVES: The initial aim of this study was to use a systems biology approach to analyse a ciprofloxacin-selected multidrug-resistant (MDR) Salmonella enterica serotype Typhimurium, L664. METHODS: The whole genome sequence and transcriptome of L664 were analysed. Site-directed mutagenesis to recreate each mutation was carried out, followed by phenotypic characterization and mutation frequency analysis. As a mutation in the TCA cycle was detected we tested the controversial hypothesis regarding ...201122186876
An outbreak of Salmonella enterica serotype Choleraesuis in goitered gazelle (Gazella subgutrosa subgutrosa) and a Malayan tapir (Tapirus indicus).An outbreak of Salmonella enterica serotype Choleraesuis enteritis occurred in two juvenile goitered gazelles and an adult Malayan tapir over a period of 5 wk at the Minnesota Zoo. Diagnosis was made postmortem on one gazelle and one tapir, and a second gazelle was diagnosed via fecal culture. The death of the tapir was attributed to S. enterica serovar Choleraesuis septicemia, while salmonellosis was considered to be a contributing factor besides ostertagiasis for the death of one goitered gaze ...201122204065
Deletion of glucose-inhibited division (gidA) gene alters the morphological and replication characteristics of Salmonella enterica Serovar typhimurium.Salmonella is an important food-borne pathogen that continues to plague the United States food industry. Characterization of bacterial factors involved in food-borne illnesses could help develop new ways to control salmonellosis. We have previously shown that deletion of glucose-inhibited division gene (gidA) significantly altered the virulence potential of Salmonella in both in vitro and in vivo models of infection. Most importantly, the gidA mutant cells displayed a filamentous morphology comp ...201122109813
Salmonella bongori provides insights into the evolution of the Salmonellae.The genus Salmonella contains two species, S. bongori and S. enterica. Compared to the well-studied S. enterica there is a marked lack of information regarding the genetic makeup and diversity of S. bongori. S. bongori has been found predominantly associated with cold-blooded animals, but it can infect humans. To define the phylogeny of this species, and compare it to S. enterica, we have sequenced 28 isolates representing most of the known diversity of S. bongori. This cross-species analysis al ...201121876672
temperature-sensitive mutants of rnase e in salmonella enterica.rnase e has an important role in mrna turnover and stable rna processing, although the reason for its essentiality is unknown. we isolated conditional mutants of rnase e to provide genetic tools to probe its essential function. in salmonella enterica serovar typhimurium, an extreme slow-growth phenotype caused by mutant ef-tu (gln125arg, tufa499) can be rescued by mutants of rnase e that have reduced activity. we exploited this phenotype to select mutations in rnase e and screened these for temp ...201121949072
Handheld device for real-time, quantitative, LAMP-based detection of Salmonella enterica using assimilating probes.A simple handheld instrument was designed to enable real-time detection of the LAMP reaction in a standard PCR tube using newly described assimilating probes as sequence-specific reporter molecules. The system was validated using DNA isolated from Salmonella enterica, demonstrating accurate temperature control with little power and little overshoot of setpoint temperatures, with rapid and accurate detection often in less than 30 min and within 20 min for reactions with high (>10(5)) genome copy ...201121982643
binding of the ramr repressor to wild-type and mutated promoters of the rama gene involved in efflux-mediated multidrug resistance in salmonella enterica serovar typhimurium.the transcriptional activator rama is involved in multidrug resistance (mdr) by increasing expression of the acrab-tolc rnd-type efflux system in several pathogenic enterobacteriaceae. in salmonella enterica serovar typhimurium (s. typhimurium), rama expression is negatively regulated at the local level by ramr, a transcriptional repressor of the tetr family. we here studied the dna-binding activity of the ramr repressor with the rama promoter (p(rama)). as determined by high-resolution footprin ...201122123696
decreased transport restores growth of a salmonella enterica apbc mutant on tricarballylate.mutants of salmonella enterica lacking apbc have nutritional and biochemical properties indicative of defects in iron-sulfur ([fe-s]) cluster metabolism. an apbc mutant is unable to grow on tricarballylate as a carbon source. based on the ability of apbc to transfer an [fe-s] cluster to an apoprotein, this defect was attributed to poor loading of the [fe-s] cluster-containing tcub enzyme. consistent with these observations, a previous study showed that overexpression of iscu, which encodes an [f ...201122101844
Influence of prior growth conditions, pressure treatment parameters, and recovery conditions on the inactivation and recovery of Listeria monocytogenes, Escherichia coli, and Salmonella Typhimurium in turkey meat.The relatively high prevalence of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella enterica serovar Typhimurium in various food products is of great concern to the food industry. The objective of this study was to determine the pressure-inactivation of the pathogens in a representative food model as affected by prior growth temperature, physiological age of the culture, pressure level and treatment temperature. The effect of post-treatment conditions (incubation temperature and g ...201122169000
Salmonella enterica serovar Typhimurium and Enteritidis infection of pigs and cytokine signalling in palatine tonsils.Pigs are considered as one of the major sources of zoonotic strains of Salmonella enterica for humans. Out of many S. enterica serovars, S. Typhimurium dominates in pigs, however, in several countries in Central Europe, S. Enteritidis is also quite frequent in pig herds. In this study we therefore compared the colonisation of pigs with S. Typhimurium and S. Enteritidis. We found that 3 weeks after infection S. Enteritidis 147 colonised the intestinal tract in higher quantities but was shed in fa ...201122019291
distinct peripheral blood rna responses to salmonella in pigs differing in salmonella shedding levels: intersection of ifng, tlr and mirna pathways.transcriptomic analysis of the response to bacterial pathogens has been reported for several species, yet few studies have investigated the transcriptional differences in whole blood in subjects that differ in their disease response phenotypes. salmonella species infect many vertebrate species, and pigs colonized with salmonella enterica serovar typhimurium (st) are usually asymptomatic, making detection of these salmonella-carrier pigs difficult. the variable fecal shedding of salmonella is an ...201122174891
nanostructured silver vanadate as a promising antibacterial additive to water-based paints.in this article, we report the use of nanostructured silver vanadate as a promising antibacterial additive to water-based paints that has potential for applications in bathrooms, kitchens, and hospital environments. this hybrid nanomaterial was prepared by a simple and fast precipitation reaction involving silver nitrate and ammonium vanadate, dismissing the hydrothermal treatment. the preparation involved using ag vanadate nanowires (β-agvo(3)) with diameters ranging from 20 to 60 nm and decora ...201122197722
Genome sequencing reveals diversification of virulence factor content and possible host adaptation in distinct subpopulations of Salmonella enterica.Divergence of bacterial populations into distinct subpopulations is often the result of ecological isolation. While some studies have suggested the existence of Salmonella enterica subsp. enterica subclades, evidence for these subdivisions has been ambiguous. Here we used a comparative genomics approach to define the population structure of Salmonella enterica subsp. enterica, and identify clade-specific genes that may be the result of ecological specialization.201121859443
Empiric antimicrobial therapy and infectious diarrhea. Do we need local guidelines?In the management of acute diarrhea, administration of antibiotics may be indicated. Appropriate antimicrobial therapy can shorten illness, reduce morbidity and can be life-saving in invasive infections. Emergence of microbial strains resistant to commonly used antibiotics means that treatment failures may become common. Because of changing patterns of resistance, knowledge of recent local patterns of susceptibility can guide the initial choice of antibiotics.201121925045
Genetic analysis of the pnp-deaD genetic region reveals membrane lipoprotein NlpI as an independent participant in cold acclimatization of Salmonella enterica serovar Typhimurium.The cold acclimatization response in many bacterial species is a tightly regulated process, which ensures the correct folding of macromolecules. In enterobacteria, this response is in part dependent on polynucleotide phosphorylase, which is encoded by the gene pnp. Based on transcriptional analysis of the pnp locus of Salmonella enterica serovar Typhimurium, we show that pnp and the adjacent membrane lipoprotein nlpI gene form an operon with both genes contributing independently to the cold accl ...201122092862
prevalence of salmonella in fecal samples of western grey kangaroos (macropus fuliginosus).this is the first extensive study of the prevalence of naturally acquired salmonella infection in wild-caught kangaroos in australia. given the close association between kangaroos, livestock, and humans and the growing popularity of kangaroo meat, it is important to identify epidemiologic factors associated with infection in these marsupials in order to minimize the risk of salmonella transmission. the overall prevalence of fecal salmonella in 645 western grey kangaroos (macropus fuliginosus) sa ...201122102658
Phenotypic and Genotypic Characterization of Salmonella enterica Recovered from Poultry Meat in Tunisia and Identification of New Genetic Traits.Abstract Thirty-seven Salmonella enterica isolates obtained from poultry meat in Tunisia were included in this study for characterization of antibiotic resistance mechanisms. High percentages of resistance were detected to ampicillin, sulfonamides, tetracycline, nalidixic acid, and streptomycin (32.4%-89.2%), and lower percentages to amoxicillin-clavulanic acid, kanamycin, amikacin, trimethoprim-sulfamethoxazol, and chloramphenicol (2.7%-18.9%). All strains showed susceptibility to ceftazidime ...201121919733
antibiotic control of tumor-colonizing salmonella enterica serovar typhimurium.systemic administration of salmonella enterica serovar typhimurium (s. typhimurium) into tumor-bearing mice results in preferential colonization of tumors and causes shrinkage and sometimes complete tumor clearance. however, in spite of these beneficial antitumor effects, the systemic administration of a bacterial pathogen raises serious safety concerns as well. addressing those concerns, here, we demonstrate that tumor-colonizing salmonella can be readily controlled by systemic administration o ...201121987828
Complete sequencing of the bla(NDM-1)-positive IncA/C plasmid from Escherichia coli ST38 isolate suggests a possible origin from plant pathogens.The complete sequence of the plasmid pNDM-1_Dok01 carrying New Delhi metallo-ß-lactamase (NDM-1) was determined by whole genome shotgun sequencing using Escherichia coli strain NDM-1_Dok01 (multilocus sequence typing type: ST38) and the transconjugant E. coli DH10B. The plasmid is an IncA/C incompatibility type composed of 225 predicted coding sequences in 195.5 kb and partially shares a sequence with bla(CMY-2)-positive IncA/C plasmids such as E. coli AR060302 pAR060302 (166.5 kb) and Salmonell ...201121966500
bacteremia and antimicrobial drug resistance over time, ghana.bacterial distribution and antimicrobial drug resistance were monitored in patients with bacterial bloodstream infections in rural hospitals in ghana. in 2001-2002 and in 2009, salmonella enterica serovar typhi was the most prevalent pathogen. although most s. enterica serovar typhi isolates were chloramphenicol resistant, all isolates tested were susceptible to ciprofloxacin.201122000360
The ERM protein, ezrin, regulates neutrophil transmigration by modulating the apical localization of MRP2 in response to the SipA effector protein during Salmonella Typhimurium infection.In human disease induced by Salmonella enterica serovar Typhimurium (S. Typhimurium), transepithelial migration of neutrophils rapidly follows attachment of the bacteria to the epithelial apical membrane. We have previously shown that during S. Typhimurium infection the multidrug resistance-associated protein 2 (MRP2) is highly expressed at the apical surface of the intestinal epithelia, and that it functions as an efflux pump for the potent neutrophil chemoattractant hepoxilin A(3) . However, t ...201121899702
reveal salmonella enteritidis test for detection of salmonella enteritidis in shell eggs and environmental samples.reveal salmonella enteritidis (se) is a lateral flow-based immunodiagnostic assay used for rapid detection of salmonella enterica serovar enteritidis from pooled shell eggs and environmental samples. this assay uses highly specific antibodies to accurately detect s. enteritidis. studies were conducted to compare the performance of this test against reference procedures for detection of s. enteritidis from both pooled shell eggs and environmental samples. pooled shell eggs were inoculated with lo ...201121919347
both the unique and repeat regions of the porphyromonas gingivalis hemagglutin a are involved in adhesion and invasion of host cells.porphyromonas gingivalis is one of the major etiologic agents of adult periodontitis and has been associated with cardiovascular diseases. it expresses multiple hemagglutinins that are significant virulence factors and play an important role in bacterial attachment and invasion of host cells. the objective of this study was to determine the impact of p. gingivalis hemagglutinin a (haga) on the attachment to and invasion of human coronary artery endothelial cells (hcaec) and gingival epithelial c ...201122100486
Host response transcriptional profiling reveals extracellular components and ABC (ATP-binding cassette) transporters gene enrichment in typhoid fever-infected Nigerian children.Salmonella enterica serovar Typhi (S. Typhi) is a human-specific pathogen that causes typhoid fever, and remains a global health problem especially in developing countries. Its pathogenesis is complex and host response is poorly understood. In Africa, typhoid fever can be a major cause of morbidity in young infected children. The onset of the illness is insidious and clinical diagnosis is often unreliable. Gold standard blood culture diagnostic services are limited, thus rapid, sensitive, and af ...201121914192
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