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differences in host cell invasion and salmonella pathogenicity island 1 expression between salmonella enterica serovar paratyphi a and nontyphoidal s. typhimurium.active invasion into nonphagocytic host cells is central to salmonella enterica pathogenicity and dependent on multiple genes within salmonella pathogenicity island 1 (spi-1). here, we explored the invasion phenotype and the expression of spi-1 in the typhoidal serovars paratyphi a compared to that of the nontyphoidal serovars typhimurium. we demonstrate that while s. typhimurium is equally invasive under both aerobic and microaerobic conditions, s. paratyphi a invades only following growth unde ...201626857569
correction: genomic comparison of non-typhoidal salmonella enterica serovars typhimurium, enteritidis, heidelberg, hadar and kentucky isolates from broiler chickens. 201626854571
the o-antigen mediates differential survival of salmonella against communities of natural predators.antigenically-distinct members of bacterial species can be differentially distributed in the environment. predators known to consume antigenically-distinct prey with different efficiencies are also differentially distributed. here we show that antigenically-distinct, but otherwise isogenic and physiologically indistinct, strains of salmonella enterica show differential survival in natural soil, sediment and intestinal environments where they would face a community of predators. decline in overal ...201626888189
characterization of quinolone resistance in salmonella spp. isolates from food products and human samples in brazil.non-typhoidal salmonellosis is an important zoonotic disease caused by salmonella enterica. the aim of this study was to investigate the prevalence of plasmid-mediated quinolone resistance in salmonella spp. and its association with fluoroquinolone susceptibility in brazil. a total of 129 nts isolates (samples from human origin, food from animal origin, environmental, and animal) grouped as from animal (n=62) and human (n=67) food were evaluated between 2009 and 2013. these isolates were investi ...201626887245
spectroscopic studies of the eutt adenosyltransferase from salmonella enterica: mechanism of four-coordinate co(ii)cbl formation.eutt from salmonella enterica is a member of a class of enzymes termed atp:co(i)rrinoid adenosyltransferases (acats), implicated in the biosynthesis of adenosylcobalamin (adocbl). in the presence of cosubstrate atp, acats raise the co(ii)/co(i) reduction potential of their cob(ii)alamin [co(ii)cbl] substrate by >250 mv via the formation of a unique four-coordinate (4c) co(ii)cbl species, thereby facilitating the formation of a "supernucleophilic" cob(i)alamin intermediate required for the format ...201626886077
high-efficiency, two-step scarless-markerless genome genetic modification in salmonella enterica.we present a two-step method for scarless-markerless genome genetic modification in salmonella enterica based on the improved suicide plasmid pgmb152. the whole laczya gene can provide a lacz-based blue/white screening strategy for fast selection of double-crossover mutants by allelic exchange. the high efficiency of this genetic engineering strategy permits the study of gene function by gene knockin, site-directed mutagenesis, and gene knockout to construct live attenuated vaccines.201626883127
compensating the fitness costs of synonymous mutations.synonymous mutations do not change the sequence of the polypeptide but they may still influence fitness. we investigated in salmonella enterica how four synonymous mutations in the rpst gene (encoding ribosomal protein s20) reduce fitness (i.e., growth rate) and the mechanisms by which this cost can be genetically compensated. the reduced growth rates of the synonymous mutants were correlated with reduced levels of the rpst transcript and s20 protein. in an adaptive evolution experiment, these f ...201626882986
phenotypic and genotypic characterization of animal-source salmonella heidelberg isolates.salmonella enterica serotype heidelberg (s. heidelberg) is frequently implicated in human foodborne salmonella infections and often produces more severe clinical disease than other serotypes. livestock and poultry products represent a potential risk for transmission to humans. the purpose of this study was to evaluate 49 s. heidelberg veterinary isolates for exponential growth rate (egr), pfge pattern, and antimicrobial resistance to evaluate these parameters as mechanisms by which s. heidelberg ...201626881274
gatifloxacin versus ceftriaxone for uncomplicated enteric fever in nepal: an open-label, two-centre, randomised controlled trial.because treatment with third-generation cephalosporins is associated with slow clinical improvement and high relapse burden for enteric fever, whereas the fluoroquinolone gatifloxacin is associated with rapid fever clearance and low relapse burden, we postulated that gatifloxacin would be superior to the cephalosporin ceftriaxone in treating enteric fever.201626809813
core proteomic analysis of unique metabolic pathways of salmonella enterica for the identification of potential drug targets.infections caused by salmonella enterica, a gram-negative facultative anaerobic bacteria belonging to the family of enterobacteriaceae, are major threats to the health of humans and animals. the recent availability of complete genome data of pathogenic strains of the s. enterica gives new avenues for the identification of drug targets and drug candidates. we have used the genomic and metabolic pathway data to identify pathways and proteins essential to the pathogen and absent from the host.201626799565
complete genome sequences of salmonella enterica serovars anatum and anatum var. 15+, isolated from retail ground turkey.the complete genome sequences of two isolates of salmonella enterica serovars anatum and anatum var. 15+ revealed the presence of two plasmids of 112 kb and 3 kb in size in each. the chromosome of salmonella anatum (4.83 mb) was slightly smaller than that of salmonella anatum var. 15+ (4.88 mb).201626798111
whole-genome sequencing of salmonella enterica subsp. enterica serovar ouakam isolated from ground turkey.in this report, we announce the first whole-genome sequencing of salmonella enterica subsp. enterica serovar ouakam strain gnt-01, isolated from ground turkey retail meat. the strain has a chromosome of 5,088,451 bp long, with a g+c content of 52.3%, and a plasmid of 109,715 bp.201626798110
complete genome and methylome sequences of two salmonella enterica spp.salmonella enterica is responsible for major foodborne outbreaks worldwide. it can cause gastroenteritis characterized by diarrhea, vomiting, and fever. salmonella infections raise public health concerns along with consequential economic impacts. in this report, we announce the first complete genome sequences of salmonella enterica subsp. enterica serovar choleraeuis (s. choleraeuis) atcc 10708 and salmonella enterica subsp. enterica serovar pullorum (s. pullorum) atcc 9120, isolated from patien ...201626798102
draft genome sequences of two salmonella enterica serotype infantis strains isolated from a captive western lowland gorilla (gorilla gorilla gorilla) and a cohabitant black and white tegu (tupinambis merianae) in brazil.the draft genome sequences of two salmonella enterica serotype infantis isolates are reported here. one of the strains was isolated from a western lowland gorilla (gorilla gorilla gorilla) with colitis. the second strain was isolated from a reptile that inhabited the same premises. whole-genome sequencing demonstrated that these isolates were not clonal.201626798099
comparison of immunomodulatory properties of mannose-binding lectins from canavalia brasiliensis and cratylia argentea in a mice model of salmonella infection.the immunomodulatory properties of mannose-binding lectins conbr (canavalia brasiliensis) and cfl (cratylia argentea) were investigated comparatively in a model of salmonella infection. the lectins were intraperitoneally (i.p.) administered to mice daily for three days before the bacterial challenge with salmonella enterica ser. typhimurium (0.2 ml i.p.; 10(7) cfu/ml). in vivo assays have shown that both lectins induced a significant leukocyte infiltration into the peritoneal cavity of uninfecte ...201626773770
complete genome and plasmid sequences of three canadian isolates of salmonella enterica subsp. enterica serovar heidelberg from human and food sources.isolates of salmonella enterica subsp. enterica serovar heidelberg are often associated with poultry products and may cause severe human illness. here, we report the fully assembled genome and plasmid sequences of three s. heidelberg strains with phage types 9, 29, and 41.201626769926
type-iii secretion filaments as scaffolds for inorganic nanostructures.nanostructured materials exhibit unique magnetic, electrical and catalytic properties. these characteristics are determined by the chemical composition, size and shape of the nanostructured components, which are challenging to modulate on such small size scales and to interface with living cells. to address this problem, we are using a self-assembling filament protein, prgi, as a scaffold for bottom-up inorganic nanostructure synthesis. prgi is a small protein (80 amino acids) that oligomerizes ...201626763334
molecular epidemiology of monophasic salmonella enterica serovar o7: -: 1, 5 isolates in akita prefecture, japan. 201626743153
differential killing of salmonella enterica serovar typhi by antibodies targeting vi and lipopolysaccharide o:9 antigen.salmonella enterica serovar typhi expresses a capsule of vi polysaccharide, while most salmonella serovars, including s. enteritidis and s. typhimurium, do not. both s. typhi and s. enteritidis express the lipopolysaccharide o:9 antigen, yet there is little evidence of cross-protection from anti-o:9 antibodies. vaccines based on vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against vi confer protection. here we investigate the role of vi capsule and antibodies ...201626741681
persistent infections by nontyphoidal salmonella in humans: epidemiology and genetics.although chronic infections by typhoidal salmonella are well-known, prolonged human infections by nontyphoidal salmonella (nts) are poorly characterized.201626740515
development and evaluation of an elime assay to reveal the presence of salmonella in irrigation water: comparison with real-time pcr and the standard culture method.a reliable, low-cost and easy-to-use elime (enzyme-linked-immuno-magnetic-electrochemical) assay for detection of salmonella enterica in irrigation water is presented. magnetic beads (mbs), coupled to a strip of eight-magnetized screen-printed electrodes localized at the bottom of eight wells (8-well/spe strip), effectively supported a sandwich immunological chain. enzymatic by-product is quickly measured by chronoamperometry, using a portable instrument. with the goal of developing a method abl ...201626717832
on the use of the electrospinning coating technique to produce antimicrobial polyhydroxyalkanoate materials containing in situ-stabilized silver nanoparticles.electro-hydrodynamic processing, comprising electrospraying and electrospinning techniques, has emerged as a versatile technology to produce nanostructured fiber-based and particle-based materials. in this work, an antimicrobial active multilayer system comprising a commercial polyhydroxyalkanoate substrate (pha) and an electrospun pha coating containing in situ-stabilized silver nanoparticles (agnps) was successfully developed and characterized in terms of morphology, thermal, mechanical, and b ...201628336838
construction and characterization of a cigr deletion mutant of salmonella enterica serovar pullorum.salmonella enterica serovar pullorum (s. pullorum) is the causative agent of pullorum disease (pd) and results in severe economic losses to the poultry industry. as a salmonella type iii secretion system 2 (t3ss2) effector and predicted membrane protein, cigr is encoded by the cigr gene within salmonella pathogenicity island 3 (spi3). in order to research the influence of the cigr gene on s. pullorum, a cigr mutant of s. pullorum s06004 was constructed by the lambda red recombination system, and ...201627163262
first case of lung abscess due to salmonella enterica serovar abony in an immunocompetent adult patient.in healthy individuals, nontyphoidal salmonella species predominantly cause a self-limited form of gastroenteritis, while they infrequently invade or cause fatal disease. extraintestinal manifestations of nontyphoidal salmonella infections are not common and mainly occur among individuals with specific risk factors; among them, focal lung infection is a rare complication caused by nontyphoidal salmonella strains typically occurring in immunocompromised patients with prior lung disease. we descri ...201627429814
tuning the catalytic activity of subcellular nanoreactors.bacterial microcompartments are naturally occurring subcellular organelles of bacteria and serve as a promising scaffold for the organization of heterologous biosynthetic pathways. a critical element in the design of custom biosynthetic organelles is quantitative control over the loading of heterologous enzymes to the interior of the organelles. we demonstrate that the loading of heterologous proteins to the 1,2-propanediol utilization microcompartment of salmonella enterica can be controlled us ...201627427532
tissue colonization and circulating t lymphocytes in laying hens upon oral challenge with salmonella enterica serovars.evaluating the potential of salmonella serovars for tissue colonization and egg contamination in laying hens is critical due to widespread consumption of poultry and egg-containing products. the 2009 fda egg rule was implemented to target the eradication of salmonella enterica enteritidis (se) from layers; however, other salmonella serovars, such as heidelberg (sh) and typhimurium (st), have also been associated with poultry-related outbreaks. we conducted this study to see if serovars other tha ...201627418660
effect of simulated sanitizer carryover on recovery of salmonella from broiler carcass rinsates.numerous antimicrobial chemicals are currently utilized as processing aids with the aim of reducing pathogenic bacteria on processed poultry carcasses. carryover of active sanitizer to a carcass rinse solution intended for recovery of viable pathogenic bacteria by regulatory agencies may cause false-negative results. this study was conducted to document the potential carryover effect of five sanitizing chemicals commonly used as poultry processing aids for broilers in a postchill dip. the effect ...201627296416
fifteen years of successful spread of salmonella enterica serovar mbandaka clone st413 in poland and its public health consequences.in the 1990s, salmonella enterica serovar (s.) mbandaka occurred in feed and poultry in poland. in the following years, the serovar also gained epidemiological importance in other eu countries. the objectives of current study were to evaluate the genetic relationship of contemporary s. mbandaka with isolates originating from the beginning of the epidemics, and to assess the contribution of poultry as the source of infections in humans. seventy s. mbandaka isolated mainly in 2009 - 2010 from huma ...201627294625
detection of salmonella spp. with the bactec 9240 automated blood culture system in 2008 - 2014 in southern iran (shiraz): biogrouping, mic, and antimicrobial susceptibility profiles of isolates.human salmonellosis continues to be a major international problem, in terms of both morbidity and economic losses. the antibiotic resistance of salmonella is an increasing public health emergency, since infections from resistant bacteria are more difficult and costly to treat.201627284396
novel antimicrobial peptides with promising activity against multidrug resistant salmonella enterica serovar choleraesuis and its stress response mechanism.to evaluate the antibacterial efficacy of novel antimicrobial peptides (amps) against multidrug-resistant (mdr) salmonella enterica serovar choleraesuis (salm. choleraesuis) and to delineate the amp-responsive mechanisms of wild-type (wt) and mdr strains.201627280957
[laboratory surveillance of salmonella enterica from human clinical cases in colombia 2005-2011].salmonella is an enteropathogen acquired through contaminated food or water. in colombia, salmonella spp. is included in the national surveillance of acute diarrhoeal diseases and typhoid fever initiated in 1997. this report shows the phenotype and genotype results obtained from 2005 to 2011.201627038678
nontyphoidal salmonella disease: current status of vaccine research and development.among more than 2500 nontyphoidal salmonella enterica (nts) serovars, s. enterica serovar typhimurium and s. enterica serovar enteritidis account for approximately fifty percent of all human isolates of nts reported globally. the global incidence of nts gastroenteritis in 2010 was estimated to be 93 million cases, approximately 80 million of which were contracted via food-borne transmission. it is estimated that 155,000 deaths resulted from nts in 2010. nts also causes severe, extra-intestinal, ...201627032517
conserved transmembrane glycine residues in the shigella flexneri polysaccharide co-polymerase protein wzzb influence protein-protein interactions.the o antigen (oag) component of lipopolysaccharides (lps) is crucial for virulence and oag chain-length regulation is controlled by the polysaccharide co-polymerase class 1 (pcp1) proteins. crystal structure analyses indicate that structural conservation among pcp1 proteins is highly maintained, however the mechanism of oag modal-chain-length control remains to be fully elucidated. shigella flexneri pcp1 protein wzzbsf confers a modal-chain length of 10-17 oag repeat units (rus), whereas the sa ...201627028755
antimicrobial susceptibility and plasmid replicon typing of salmonella enterica serovar kentucky isolates recovered from broilers.salmonella kentucky has become the predominant serovar recovered from broilers slaughtered in the united states, and the prevalence of antimicrobial resistance (amr) has increased dramatically in this serovar. relationships between amr, genotype, and plasmid replicon types were characterized for 600 salmonella kentucky isolates recovered from chicken carcasses from 2004 to 2013. pulsed-field gel electrophoresis cluster analysis revealed 112 unique types sharing 79% similarity. over half of the i ...201627028167
draft whole-genome sequences of salmonella enterica subsp. enterica serovars enteritidis, veneziana, and salford, isolated from herbs.salmonellais a foodborne pathogen found in a wide variety of sources. here, we report draft genome sequences of threesalmonella entericasubsp.entericaserovars found in herbs: enteritidis, veneziana, and salford, with the latter two being extremely rare in california.201627013038
l-2,3-diaminopropionate generates diverse metabolic stresses in salmonella enterica.unchecked amino acid accumulation in living cells has the potential to cause stress by disrupting normal metabolic processes. thus, many organisms have evolved degradation strategies that prevent endogenous accumulation of amino acids. l-2,3-diaminopropionate (dap) is a non-protein amino acid produced in nature where it serves as a precursor to siderophores, neurotoxins and antibiotics. dap accumulation in salmonella enterica was previously shown to inhibit growth by unknown mechanisms. the prod ...201627010356
emergence and diversity of salmonella enterica serovar indiana isolates with concurrent resistance to ciprofloxacin and cefotaxime from patients and food-producing animals in china.salmonellosis is a major global foodborne infection, and strains that are resistant to a great variety of antibiotics have become a major public health concern. the aim of this study was to identify genes conferring resistance to fluoroquinolones and extended-spectrum β-lactams in nontyphoidal salmonella (nts) from patients and food-producing animals in china. in total, 133 and 21 nts isolates from animals and humans, respectively, exhibiting concurrent resistance to ciprofloxacin and cefotaxime ...201627001808
whole genome sequencing provides insights into the genetic determinants of invasiveness in salmonella dublin.salmonella enterica subsp. enterica serovar dublin (s. dublin) is one of the non-typhoidal salmonella (nts); however, a relatively high proportion of human infections are associated with invasive disease. we applied whole genome sequencing to representative invasive and non-invasive clinical isolates of s. dublin to determine the genomic variations among them and to investigate the underlying genetic determinants associated with invasiveness in s. dublin. although no particular genomic variation ...201626996313
broilers with low serum mannose-binding lectin show increased fecal shedding of salmonella enterica serovar montevideo.mannose-binding lectin (mbl) is a key molecule in innate immunity. mbl binds to carbohydrates on the surface of pathogens, initiating the complement system via the lectin-dependent pathway or facilitates opsonophagocytosis. in vivo studies using inbred chicken lines differing in mbl serum concentration indicate that chicken mbl affects salmonella resistance; further studies are imperative in conventional broiler chickens. in this study 104 conventional day-old chickens (offspring from a cross be ...201626994208
complete genome and methylome sequences of salmonella enterica subsp. enterica serovar panama (atcc 7378) and salmonella enterica subsp. enterica serovar sloterdijk (atcc 15791).salmonella enterica spp. are pathogenic bacteria commonly associated with food-borne outbreaks in human and animals. salmonella enterica spp. are characterized into more than 2,500 different serotypes, which makes epidemiological surveillance and outbreak control more difficult. in this report, we announce the first complete genome and methylome sequences from two salmonella type strains associated with food-borne outbreaks, salmonella enterica subsp. enterica serovar panama (atcc 7378) and salm ...201626988049
phenotypic and genotypic diversity of salmonella in finishing swine.salmonella enterica (nontyphoidal) is one of the major causes of foodborne diseases in the united states and worldwide. molecular typing methods are significant tools used to better understand the transmission and ecology of salmonella in order to implement pre-harvest control measures. the objectives of this study were to describe the salmonella genotypes, the distribution of isolate subtypes from different ecological niches (i.e., barn environment, nursery, and individual pigs) and their evolu ...201626977814
global mlst of salmonella typhi revisited in post-genomic era: genetic conservation, population structure, and comparative genomics of rare sequence types.typhoid fever, caused by salmonella enterica serovar typhi, remains an important public health burden in southeast asia and other endemic countries. various genotyping methods have been applied to study the genetic variations of this human-restricted pathogen. multilocus sequence typing (mlst) is one of the widely accepted methods, and recently, there is a growing interest in the re-application of mlst in the post-genomic era. in this study, we provide the global mlst distribution of s. typhi ut ...201626973639
presence of plasmid-mediated quinolone resistance determinants and mutations in gyrase and topoisomerase in salmonella enterica isolates with resistance and reduced susceptibility to ciprofloxacin.in recent decades, the emergence and spread of resistance to nalidixic acid are usually associated with reduced susceptibility to ciprofloxacin among salmonella serotypes. the aims of this study were to investigate the mechanisms associated with resistance to fluoroquinolone and the clonal relatedness of salmonella strains isolated from human and nonhuman origins, in a 5-year period in são paulo, brazil. antimicrobial susceptibility testing for salmonella isolates was performed. pcr and dna sequ ...201626971183
development of a simple, peripheral-blood-based lateral-flow dipstick assay for accurate detection of patients with enteric fever.enteric fever is a systemic infection caused by typhoidal strains of salmonella enterica and is a significant cause of mortality and morbidity in many parts of the world, especially in resource-limited areas. unfortunately, currently available diagnostic tests for enteric fever lack sensitivity and/or specificity. no true clinically practical gold standard for diagnosing patients with enteric fever exists. unfortunately, microbiologic culturing of blood is only 30 to 70% sensitive although 100% ...201626961857
salmonella typhimurium undergoes distinct genetic adaption during chronic infections of mice.typhoid fever caused by salmonella enterica serovar typhi (s. typhi) is a severe systemic human disease and endemic in regions of the world with poor drinking water quality and sewage treatment facilities. a significant number of patients become asymptomatic life-long carriers of s. typhi and serve as the reservoir for the disease. the specific mechanisms and adaptive strategies enabling s. typhi to survive inside the host for extended periods are incompletely understood. yet, elucidation of the ...201626955808
draft genome sequence of a salmonella enterica subsp. enterica serovar gallinarum bv. gallinarum isolate associated with fowl typhoid outbreaks in brazil.salmonella enterica subsp. enterica serovar gallinarum bv. gallinarum strains are bird pathogens causing fowl typhoid (ft). isolate br_rs12 was obtained from a poultry flock with ft in 2014. the sequencing of this genome will enable to track the origin of the recent outbreaks in brazil.201626950322
assessing the growth of escherichia coli o157:h7 and salmonella in spinach, lettuce, parsley and chard extracts at different storage temperatures.the objective of this work was to study the growth potential of escherichia coli o157:h7 and salmonella spp. in leafy vegetable extracts at different temperature conditions.201626950043
effective photosensitization-based inactivation of gram (-) food pathogens and molds using the chlorophyllin-chitosan complex: towards photoactive edible coatings to preserve strawberries.this study is focused on the novel approaches to enhance the inactivation of the gram (-) food pathogen salmonella enterica and harmful molds in vitro and on the surface of strawberries using the chlorophyllin-chitosan complex. salmonella enterica (∼1 × 10(7) cfu ml(-1)) was incubated with chlorophyllin 1.5 × 10(-5) m (chl, food additive), chitosan 0.1% (chs, food supplement) or the chlorophyllin-chitosan complex (1.5 × 10(-5) m chl-0.1% chs) and illuminated with visible light (λ = 405 nm, light ...201626947225
colonization of internal organs by salmonella enteritidis in experimentally infected laying hens housed in enriched colony cages at different stocking densities.epidemiologic analyses have linked the frequency of human infections with salmonella enterica subspecies enterica serovar enteritidis to the consumption of contaminated eggs and thus to the prevalence of this pathogen in commercial egg-laying flocks. contamination of the edible contents of eggs by salmonella enteritidis is a consequence of the colonization of reproductive tissues in systemically infected hens. the animal welfare implications of laying hen housing systems have been widely debated ...201626944976
differential antibacterial response of chicken granulosa cells to invasion by salmonella serovars.in the united states, salmonella enterica ser. enteritidis (se) is among the leading bacterial cause of foodborne illness via consumption of raw or undercooked eggs. the top salmonella serovars implicated in u.s. foodborne outbreaks associated with chicken consumption include se, typhimurium (st), heidelberg (sh), montevideo, mbandka, braenderup, and newport. while enforcement actions target the eradication of se from layer hens, there is a growing concern that other serovars could occupy this n ...201626944965
development of a loop mediated isothermal amplification (lamp) - surface enhanced raman spectroscopy (sers) assay for the detection of salmonella enterica serotype enteritidis.as a major foodborne pathogen, salmonella enterica serotype enteritidis is increasingly rising as a global health concern. here, we developed an integrated assay that combines loop mediated isothermal amplification (lamp) and surface enhanced raman spectroscopy (sers) for dna detection of s. enteritidis using specifically designed raman active au-nanoprobes. the target dna was amplified by lamp and then labeled with au-nanoprobes comprised of gold nanoparticle-modified with specific cy5/dna prob ...201626941845
study of salmonella typhimurium infection in laying hens.members of salmonella enterica are frequently involved in egg and egg product related human food poisoning outbreaks worldwide. in australia, salmonella typhimurium is frequently involved in egg and egg product related foodborne illness and salmonella mbandaka has also been found to be a contaminant of the layer farm environment. the ability possessed by salmonella enteritidis to colonize reproductive organs and contaminate developing eggs has been well-described. however, there are few studies ...201626941727
draft whole-genome sequences of 25 salmonella enterica strains representing 24 serovars.we report the draft genome sequences of 25 salmonella enterica strains representing 24 different serotypes, many of which were not available in public repositories during our selection process. these draft genomes will provide useful reference for the genetic variation between serotypes and aid in the development of molecular typing tools.201626941156
new insights about excisable pathogenicity islands in salmonella and their contribution to virulence.pathogenicity islands (pais) are regions of the chromosome of pathogenic bacteria that harbor virulence genes, which were probably acquired by lateral gene transfer. several pais can excise from the bacterial chromosome by site-specific recombination and in this review have been denominated "excisable pais". here, the characteristic of some of the excisable pais from salmonella enterica and the possible role and impact of the excision process on bacterial virulence is discussed. understanding th ...201626939722
genome-scale screening and validation of targets for identification of salmonella enterica and serovar prediction.salmonella enterica is the most common foodborne pathogen worldwide, with 2,500 recognized serovars. detection of s. enterica and its classification into serovars are essential for food safety surveillance and clinical diagnosis. the pcr method is useful for these applications because of its rapidity and high accuracy. we obtained 412 candidate detection targets for s. enterica using a comparative genomics mining approach. gene ontology (go) functional enrichment analysis of these candidate targ ...201626939647
strain-specific survival of salmonella enterica in peanut oil, peanut shell, and chia seeds.in north america, outbreaks of salmonella have been linked to low-water activity (aw) foods, such as nuts and seeds. these outbreaks have implicated an assortment of salmonella serotypes. some salmonella serotypes (e.g., enteritidis and typhimurium) cause high proportions of salmonellosis. nevertheless, there has recently been an emergence of uncommon salmonella serotypes and strains (e.g., tennessee, hartford, and thompson) in low-aw foods. the aim of this study was to evaluate the survival cha ...201626939645
autoregulation of the tufb operon in salmonella.in salmonella enterica and related species, translation elongation factor ef-tu is encoded by two widely separated but near-identical genes, tufa and tufb. two thirds of ef-tu is expressed from tufa with the remaining one third coming from tufb. inactivation of tufa is partly compensated by a doubling in the amount of ef-tub but the mechanism of this up-regulation is unknown. by experimental evolution selecting for improved growth rate in a strain with an inactive tufa we selected six different ...201626934594
prevalence of salmonella excretion in stool: a community survey in 2 sites, guinea-bissau and senegal.chronic and convalescent carriers play an important role in the transmission and endemicity of many communicable diseases. a high incidence of salmonella enterica serovar typhi and invasive nontyphoidal salmonella (nts) infection has been reported in parts of sub-saharan africa, yet the prevalence of salmonella excretion in the general population is unknown.201626933022
a multicountry molecular analysis of salmonella enterica serovar typhi with reduced susceptibility to ciprofloxacin in sub-saharan africa.salmonella enterica serovar typhi is a predominant cause of bloodstream infections in sub-saharan africa (ssa). increasing numbers of s. typhi with resistance to ciprofloxacin have been reported from different parts of the world. however, data from ssa are limited. in this study, we aimed to measure the ciprofloxacin susceptibility of s. typhi isolated from patients with febrile illness in ssa.201626933020
challenges and opportunities for typhoid fever control: a call for coordinated action.the burden of enteric fever caused by salmonella enterica serovars typhi and paratyphi is substantial and has high impact in toddlers and young children. this burden is relatively well documented in asia, and this supplement provides new data on the substantial burden in several sub-saharan african countries. challenges in standardized surveillance and imperfect diagnostic tools have resulted in patchy local disease data, which are not well acknowledged or integrated into local country evidence ...201626933019
diagnosing salmonella enterica serovar typhi infections by polymerase chain reaction using edta blood samples of febrile patients from burkina faso.globally, there are an estimated 22 million cases of salmonella enterica serovar typhi infection each year. however, this figure is likely to be an underestimate due to the low sensitivity of blood culture in s. typhi diagnosis. the aim of this study was to diagnose s. typhi by conventional polymerase chain reaction (pcr) using patient's blood preserved with ethylenediamine tetraacetic acid (edta).201626933018
variations of invasive salmonella infections by population size in asante akim north municipal, ghana.the typhoid fever surveillance in africa program (tsap) estimated adjusted incidence rates (irs) for salmonella enterica serovar typhi and invasive nontyphoidal s. enterica serovars (ints) of >100 cases per 100 000 person-years of observation (pyo) for children aged <15 years in asante akim north municipal (aan), ghana, between march 2010 and may 2012. we analyzed how much these rates differed between rural and urban settings.201626933015
what have we learned from the typhoid fever surveillance in africa program?the typhoid fever surveillance in africa program (tsap) was established in 2009 to fill the data void concerning invasive salmonella disease in sub-saharan africa, and to specifically estimate the burden of bloodstream infections caused by the key pathogen, salmonella enterica serovar typhi. tsap has achieved this ambitious target, finding high incidences of typhoid fever in both rural and urban populations in several countries in sub-saharan africa. the results of tsap will undoubtedly dictate ...201626933014
unraveling the effects of static magnetic field stress on cytosolic proteins of salmonella by using a proteomic approach.the present study investigated the adaptation of salmonella enterica subsp. enterica serovar hadar to static magnetic field (smf) exposure (200 mt, 9 h). the proteomic analysis provides an overview of potentially important cytosolic proteins that salmonella needs to regulate to survive and adapt to magnetic stress. via 2-dimensional electrophoresis and liquid chromatography tandem mass spectrometry, we compared cytosolic proteomes before and after exposure to magnetic field. a total of 35 protei ...201626928316
mechanisms of resistance to linalool in salmonella senftenberg and their role in survival on basil.fresh produce contaminated with human pathogens raises vital and ecological questions about bacterial survival strategies. such occurrence was basil harboring salmonella enterica serovar senftenberg that caused an outbreak in 2007. this host was unanticipated due to its production of antibacterial substances, including linalool. we show that linalool perforates bacterial membranes, resulting in increased permeability and leakage of vital molecules. it also inhibits cell motility and causes bacte ...201626914987
genome sequences of salmonella enterica subsp. enterica serovar lubbock strains isolated from liver abscesses of feedlot cattle.the genome sequencing of 13 salmonella enterica subsp. enterica serovar lubbock strains isolated from liver abscesses of feedlot cattle is reported here. the availability of these genomes will help to further understand the etiologic role of salmonella strains in liver abscesses of cattle and will serve as references in microbial trace-back studies to improve food safety.201627151794
draft genome sequences of 37 salmonella enterica strains isolated from poultry sources in nigeria.here, we report the availability of draft genomes of several salmonella serotypes, isolated from poultry sources from nigeria. these genomes will help to further understand the biological diversity of s. enterica and will serve as references in microbial trace-back studies to improve food safety.201627151793
a multischool outbreak due to salmonella enterica serovar napoli associated with elevated rates of hospitalizations and bacteremia, milan, italy, 2014.a multischool outbreak of salmonellosis caused by salmonella enterica serovar napoli was investigated in the province of milan from october to november 2014, following an increase in school absenteeism coinciding with two positive cases. epidemiological studies detected 47 cases in four primary schools: 46 children and 1 adult woman (51.4% males and 48.6% females, median age 8.9). from these, 14 cases (29.8%) were severe and resulted in hospitalization, including 6 children (12.8%) who developed ...201627148636
chitin mixed in potting soil alters lettuce growth, the survival of zoonotic bacteria on the leaves and associated rhizosphere microbiology.chitin is a promising soil amendment for improving soil quality, plant growth, and plant resilience. the objectives of this study were twofold. first, to study the effect of chitin mixed in potting soil on lettuce growth and on the survival of two zoonotic bacterial pathogens, escherichia coli o157:h7 and salmonella enterica on the lettuce leaves. second, to assess the related changes in the microbial lettuce rhizosphere, using phospholipid fatty acid (plfa) analysis and amplicon sequencing of a ...201627148242
preventing invasive salmonellosis in children through vaccination.vaccination is an important strategy to control endemic enteric fever (ef) and to interrupt transmission during outbreaks. the main aim of this paper is to discuss the efficacy of available ef vaccines in children and to highlight novel vaccination possibilities against ef and non-typhoid invasive salmonelloses.201627140662
altered virulence potential of salmonella enteritidis cultured in different foods: a cumulative effect of differential gene expression and immunomodulation.salmonella enterica serovars enteritidis (s. enteritidis) is one of the most common causes of food borne illness. bacterial growth environment plays an important role in regulating gene expression thereby affecting the virulence profile of the bacteria. different foods present diverse growth conditions which may affect the pathogenic potential of the bacteria. in the present study, the effect of food environments on the pathogenic potential of s. enteritidis has been evaluated. s. enteritidis wa ...201627132148
salmonella pneumonia complicated with encysted empyema in an immunocompromised youth: case report and literature review.in this case report we described a bahraini male patient of twenty years of age, a smoker and diagnosed with stage iv b hodgkin lymphoma. he presented with fever, nonproductive cough, upper back pain and shortness of breath due to right upper lobe pneumonia with right encysted pleural effusion. salmonella enterica serotype enteritidis was isolated from the sputum. he was successfully treated with 2 weeks of ceftriaxone followed by 2 weeks of oral cefixime. this was the first case of encysted emp ...201627131011
carriage prevalence of salmonella enterica serotype typhi in gallbladders of adult autopsy cases from mozambique.typhoid fever is an important public health problem in many low-income countries where asymptomatic carriers play an important role in its dissemination. the bacterium causing typhoid fever can live in the gallstones of asymptomatic persons after the infection. these carriers are reservoirs of s. typhi, are highly contagious, and spread the disease through the secretion of bacteria in feces and urine. the aim of this study was to determine the carrier rate in an area of mozambique.201627131005
emergence of host-adapted salmonella enteritidis through rapid evolution in an immunocompromised host.host adaptation is a key factor contributing to the emergence of new bacterial, viral and parasitic pathogens. many pathogens are considered promiscuous because they cause disease across a range of host species, while others are host-adapted, infecting particular hosts(1). host adaptation can potentially progress to host restriction where the pathogen is strictly limited to a single host species and is frequently associated with more severe symptoms. host-adapted and host-restricted bacterial cl ...201627127642
emergence of blactx-m-15, blatem-169 and blaper-1 extended-spectrum β-lactamase genes among different salmonella enterica serovars from human faecal samples.broad-spectrum β-lactams are used for empirical therapy of severe infections with non-typhoid salmonella serotypes; however, activities of these drugs against the strains producing different β-lactamase is not so clear. this study investigated the prevalence of β-lactamase genes among isolates of s. enterica serovars from human faecal samples and determined their diversity in activity against different β-lactams.201627117981
analysis of the fluoroquinolone antibiotic resistance mechanism of salmonella enterica isolates.quinolone-resistant salmonella strains were isolated from patient samples, and several quinolone-sensitive strains were used to analyze mutations in the quinolone resistance-determining region (qrdr) of gyra, gyrb, parc, and pare and to screen for plasmid-mediated quinolone resistance. among the 21 strains that showed resistance to nalidixic acid and ciprofloxacin (mic 0.125-2.0 μg/ml), 17 strains had a mutation in qrdr codon 87 of gyra, and 3 strains had a single mutation (ser83 → phe). another ...201627116992
nosocomial outbreak of a novel extended-spectrum β-lactamase salmonella enterica serotype isangi among surgical patients.objective nosocomial outbreaks caused by salmonella are rare. we describe the investigation and control of a cluster of novel extended-spectrum β-lactamase (esbl) salmonella enterica serotype isangi in a hospital in southeastern michigan. methods an epidemiologic investigation, including case-control study, assessment of infection control practices and environmental cultures, was performed to identify modes of transmission. healthcare workers (hcws) exposed to case patients were screened. strain ...201627108715
mp-v1 from the venom of social wasp vespula vulgaris is a de novo type of mastoparan that displays superior antimicrobial activities.mastoparans from the venom of social wasps have attracted considerable attention as effective antibiotic candidates. in this study, mastoparan v1 (mp-v1) from vespula vulgaris was first disclosed to have a peptide amino acid sequence distinct from typical mastoparans and its biochemical properties and antimicrobial effects were compared with those of typical mastoparans mp-l, -x(v) and -b. circular dichroism (cd) spectroscopy revealed that mp-v1 and -x(v) form more stable α-helical conformations ...201627104500
draft genome sequences of salmonella enterica subsp. enterica serovar berta atcc 8392 and a nalidixic acid-resistant isolate of this strain.italic! salmonella entericasubspecies italic! entericaserovar berta has been isolated in multiple animal species and has been implicated in human disease. here, we report a 4.7-mbp draft genome sequence of italic! s. entericaserovar berta (atcc strain 8392) and a nalidixic acid-resistant isolate derived from this strain.201627103707
generation of a naïve human single chain variable fragment (scfv) library for the identification of monoclonal scfv against salmonella typhi hemolysin e antigen.antibody phage display is a useful tool for the isolation and identification of monoclonal antibodies. naive antibody libraries are able to overcome the limitations associated with the traditional hybridoma method for monoclonal antibody generation. antibody phage display is also a preferred method for antibody generation against toxins as it does not suffer from toxicity mediated complications. here, we describe a naïve multi ethnic scfv antibody library generated via two-step cloning with an e ...201627090555
genome sequence of the fish pathogen yersinia ruckeri sc09 provides insights into niche adaptation and pathogenic mechanism.yersinia ruckeri is the etiologic agent of enteric red mouth disease (erm), a severe fish disease prevailing in worldwide aquaculture industries. here we report for the first time the complete genome of y. ruckeri (yersinia ruckeri) sc09, a highly virulent strain isolated from ictalurus punctatus with severe septicemia. sc09 possesses a single chromosome of 3,923,491 base pairs, which contains 3651 predicted protein coding sequences (cds), 19 rrna genes, and 79 trna genes. among the cds, we have ...201627089334
serotypes and antimicrobial resistance of salmonella enterica isolated from pork, chicken meat and lettuce, bangkok and central thailand.food of animal origins, particularly pork and chicken meat, has long been recognized as major sources of human salmonellosis. there have been recent reports of human salmonellosis outbreaks due to consumption of leafy green vegetables such as lettuce. in this study, 120 (40 pork, 40 chicken meat and 40 lettuce) samples were randomly collected from retail markets in bangkok and central thailand during june to august 2015 for salmonella serotype identification and antimicrobial susceptibility test ...201627086423
status of paratyphoid fever vaccine research and development.salmonella enterica serovars typhi and paratyphi (s. paratyphi) a and b cause enteric fever in humans. of the paratyphoid group, s. paratyphi a is the most common serovar. in 2000, there were an estimated 5.4 million cases of s. paratyphi a worldwide. more recently paratyphoid fever has accounted for an increasing fraction of all cases of enteric fever. although vaccines for typhoid fever have been developed and in use for decades, vaccines for paratyphoid fever have not yet been licensed. sever ...201627083427
transmissible plasmid containing salmonella enterica heidelberg isolates modulate cytokine production during early stage of interaction with intestinal epithelial cells.the variation in cytokine production during bacterial invasion of human intestinal epithelial cells (iecs) is a contributing factor for progression of the infection. a few salmonella enterica heidelberg strains isolated from poultry products harbor transmissible plasmids (tps), including those that encode a type-iv secretion system. earlier, we showed that these tps are responsible for increased virulence during infection. this study examines the potential role of these tps in cytokine productio ...201627082282
the type three secreted effector sipc regulates the trafficking of perp during salmonella infection.salmonella enterica typhimurium employs type iii secreted effectors to induce cellular invasion and pathogenesis. we previously reported the secreted effector sipa is in part responsible for inducing the apical accumulation of the host membrane protein perp, a host factor we have shown is key to the inflammatory response induced by salmonella. we now report that the s. typhimurium type iii secreted effector sipc significantly contributes to perp redistribution to the apical membrane surface. to ...201627078059
salmonella infection and carriage in reptiles in a zoological collection.objective to identify important subspecies and serovars of salmonella enterica in a captive reptile population and clinically relevant risk factors for and signs of illness in salmonella-positive reptiles. design retrospective cross-sectional study. animals 11 crocodilians (4 samples), 78 snakes (91 samples), 59 lizards (57 samples), and 34 chelonians (23 samples) at the bronx zoo from 2000 through 2012. procedures data pertaining to various types of biological samples obtained from reptiles wit ...201627074614
transfer rna bound to mnmh protein is enriched with geranylated trna--a possible intermediate in its selenation?the wobble nucleoside 5-methylaminomethyl-2-thio-uridine (mnm5s2u) is present in bacterial trnas specific for lys and glu and 5-carboxymethylaminomethyl-2-thio-uridine (cmnm5s2u) in trna specific for gln. the sulfur of (c)mnm5s2u may be exchanged by selenium (se)-a reaction catalyzed by the selenophosphate-dependent trna 2-selenouridine synthase encoded by the mnmh (ybbb, selu, sufy) gene. the mnmh protein has a rhodanese domain containing one catalytic cys (c97) and a p-loop domain containing a ...201627073879
dksa-dependent transcriptional regulation in salmonella experiencing nitrosative stress.redox-based signaling is fundamental to the capacity of bacteria to sense, and respond to, nitrosative and oxidative stress encountered in natural and host environments. the conserved rna polymerase regulatory protein dksa is a thiol-based sensor of reactive nitrogen and oxygen species. dksa-dependent transcriptional control promotes antinitrosative and antioxidative defenses that contribute to salmonella pathogenesis. the specific adaptive changes mediated by dksa in response to reactive specie ...201627065993
expression and secretion pattern of fljb of salmonella enterica serovar typhi in different culture conditions. 201627057676
the typhoid toxin promotes host survival and the establishment of a persistent asymptomatic infection.bacterial genotoxins, produced by several gram-negative bacteria, induce dna damage in the target cells. while the responses induced in the host cells have been extensively studied in vitro, the role of these effectors during the course of infection remains poorly characterized. to address this issue, we assessed the effects of the salmonella enterica genotoxin, known as typhoid toxin, in in vivo models of murine infection. immunocompetent mice were infected with isogenic s. enterica, serovar ty ...201627055274
fluorescence-based thermal shift data on multidrug regulator acrr from salmonella enterica subsp. entrica serovar typhimurium str. lt2.the fluorescence-based thermal shift (fts) data presented here include table s1 and fig. s1, and are supplemental to our original research article describing detailed structural, fts, and fluorescence polarization analyses of the salmonella enterica subsp. entrica serovar typhimurium str. lt2 multidrug transcriptional regulator acrr (stacrr) (doi:10.1016/j.jsb.2016.01.008) (manjasetty et al., 2015 [1]). table s1 contains chemical formulas, a chemical abstracts service (cas) registry number (cas ...201627054155
evaluation the antibacterial effects of echinophora platyloba extracts against some salmonella species.salmonellosis, which is caused by nontyphoid salmonella bacteria, is one of the most common foodborne diseases, and it causes gastrointestinal infections worldwide, most of which are limited gastroenteritis that requires antimicrobial treatment. the aim of this study was to investigate the effects of echinophora platyloba extract on inhibiting the growth of salmonella typhi, salmonella enteritidis, and salmonella choleraesuis.201627054002
genetic relatedness of salmonella serovars isolated from catfish (clarias gariepinus) and tilapia (tilapia mossambica) obtained from wet markets and ponds in penang, malaysia.a total of 43 salmonella enterica isolates belonging to different serovars (salmonella albany, salmonella agona, salmonella corvallis, salmonella stanley, salmonella typhimurium, salmonella mikawasima, and salmonella bovismorbificans) were isolated from catfish (clarias gariepinus) and tilapia (tilapia mossambica) obtained from nine wet markets and eight ponds in penang, malaysia. thirteen, 19, and 11 isolates were isolated from 9 of 32 catfish, 14 of 32 tilapia, and 11 of 44 water samples, resp ...201627052872
irradiance and temperature influence the bactericidal effect of 460-nanometer light-emitting diodes on salmonella in orange juice.blue light-emitting diodes (leds) have been known to produce an antibacterial effect on various pathogenic bacteria. to extend this application to foods, blue 460-nm leds were evaluated for their antibacterial effect on salmonella in orange juice. a cocktail of salmonella enterica serovars gaminara, montevideo, newport, typhimurium, and saintpaul was inoculated into pasteurized orange juice and illuminated with 460-nm leds at irradiances of 92, 147.7, and 254.7 mw/cm(2) and temperatures of 4, 12 ...201627052858
diagnostic accuracy of rectoanal mucosal swab of feedlot cattle for detection and enumeration of salmonella enterica.cattle are noted carriers of the foodborne pathogen salmonella enterica. the perceived need to decrease the potential human health risk posed by excretion of this pathogen has resulted in numerous studies examining the factors that influence salmonella shedding in cattle. fecal grab (fg) samples have been the predominant method used to identify cattle colonized or infected with salmonella; however, fg sampling can be impractical in certain situations, and rectoanal mucosal swabs (rams) are a mor ...201627052855
evaluation of corn oil as an additive in the pre-enrichment step to increase recovery of salmonella enterica from oregano.phenolic compounds associated with essential oils of spices and herbs possess a variety of antioxidant and antimicrobial properties that interfere with salmonella detection from fresh and dried products. finding a compound to neutralize the effect of these antimicrobial compounds, while allowing salmonella growth during pre-enrichment, is a crucial step in both traditional pathogen isolation and molecular detection from these foods. this study evaluated the effectiveness of corn oil as a compone ...201627052719
prevalence and characterization of multi-drug resistant salmonella enterica serovar gallinarum biovar pullorum and gallinarum from chicken.salmonella is an important zoonotic pathogen responsible for animal and human diseases. the aim of the present study was to determine the prevalence and stereotyping of salmonella isolates isolated from apparently healthy poultry. furthermore, the clonal relatedness among the isolated salmonella serovars was assessed.201627051187
serodiagnosis of acute typhoid fever in nigerian pediatric cases by detection of serum iga and igg against hemolysin e and lipopolysaccharide.inexpensive, easy-to-use, and highly sensitive diagnostic tests are currently unavailable for typhoid fever. to identify candidate serodiagnostic markers, we have probed microarrays displaying the full salmonella enterica serovar typhi (s. typhi) proteome of 4,352 different proteins + lipopolysaccharides (lpss), with sera from nigerian pediatric typhoid and other febrile cases, nigerian healthy controls, and healthy u.s. adults. nigerian antibody profiles were broad (∼500 seropositive antigens) ...201627215295
rflm mediates target specificity of the rcscdb phosphorelay system for transcriptional repression of flagellar synthesis in salmonella enterica.the bacterial flagellum enables directed movement of salmonella enterica towards favorable conditions in liquid environments. regulation of flagellar synthesis is tightly controlled by various environmental signals at transcriptional and post-transcriptional levels. the flagellar master regulator flhd4 c2 resides on top of the flagellar transcriptional hierarchy and is under autogenous control by flhd4 c2 -dependent activation of the repressor rflm. the inhibitory activity of rflm depends on the ...201627206164
effect of reduced graphene oxide-hybridized zno thin films on the photoinactivation of staphylococcus aureus and salmonella enterica serovar typhi.the immobilization of photocatalyst nanoparticles on a solid substrate is an important aspect for improved post-treatment separation and photocatalyst reactor design. in this study, we report the simple preparation of reduced graphene oxide (rgo)-hybridized zinc oxide (zno) thin films using a one-step electrochemical deposition, and investigated the effect of rgo-hybridization on the photoinactivation efficiency of zno thin films towards staphylococcus aureus (s. aureus) and salmonella enterica ...201627203568
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