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inactivation of salmonella on sprouting seeds using a spontaneous carvacrol nanoemulsion acidified with organic acids.over the past decade, demand has increased for natural, minimally processed produce, including sprout-based products. sanitization with 20,000 ppm of calcium hypochlorite is currently recommended for all sprouting seeds before germination to limit sprout-related foodborne outbreaks. a potentially promising disinfectant as an alternative to calcium hypochlorite is acidified spontaneous essential oil nanoemulsions. in this study, the efficacy of an acidified carvacrol nanoemulsion was tested again ...201627357030
application of a nonlinear model to transcript levels of upregulated stress response gene ibpa in stationary-phase salmonella enterica subjected to sublethal heat stress.sublethal heating, which can occur during slow cooking of meat products, is known to induce increased thermal resistance in salmonella. however, very few studies have addressed the kinetics of this response. although several recent studies have reported improved thermal inactivation models that include the effect of prior sublethal history on subsequent thermal resistance, none of these models were based on cellular-level responses to sublethal thermal stress. the goal of this study was to deter ...201627357027
salmonella infection in healthy pet reptiles: bacteriological isolation and study of some pathogenic characters.the fecal samples from 213 captive reptiles were examined, and 29 (13.61%) salmonella enterica isolates were detected: 14/62 (22.58%) from chelonians, 14/135 (10.37%) from saurians, and 1/16 (6.25%) from ophidians. the isolates were distributed among 14 different serotypes: miami, ebrie, hermannsweder, tiergarten, tornov, pomona, poona, goteborg, abaetetube, nyanza, kumasi, typhimurium, 50:b:z6, 9,12:z29:1,5, and a non-motile serotype with antigenic formula 1,4,[5],12:-:-. salmonella typhimurium ...201627352973
six cases of paratyphoid fever due to salmonella paratyphi a in travelers returning from myanmar between july 2014 and august 2015.we report six cases of salmonella enterica serotype paratyphi a infections in travelers returning from myanmar. in 2015, 31 cases of paratyphoid fever were reported in japan, and 54.8% of those traveled to myanmar. among them, six patients presented to our hospital. they had traveled to myanmar from july 2014 to august 2015 for business purposes. all six isolates were phage type 1, and they were resistant to nalidixic acid.201627352874
two propanediol utilization-like proteins of moorella thermoacetica with phosphotransacetylase activity.moorella thermoacetica is one of the model acetogenic bacteria for the resolution of the wood-ljungdahl (acetyl-coa) pathway in which co2 is autotrophically assimilated yielding acetyl-coa as central intermediate. its further conversion into acetate relies on subsequent phosphotransacetylase (pta) and acetate kinase reactions. however, the genome of m. thermoacetica contains no pta homologous gene. it has been speculated that the moth_0864 and moth_1181 gene products sharing similarities with an ...201627338272
invasive infections with nontyphoidal salmonella in sub-saharan africa.invasive nontyphoidal salmonella (nts) infections in africa cause an enormous burden of illness. these infections are often devastating, with mortality estimated at 20%, even with appropriate antimicrobial therapy. two major groups-young children and hiv-infected adults-suffer the great majority of these infections. in children, younger age itself, as well as malaria, malnutrition, and hiv infection, are prominent risk factors. in adults, hiv infection is by far the most important risk factor. t ...201627337467
co-occurrence of mcr-1 and esbl on a single plasmid in salmonella enterica. 201627330065
detection of an mcr-1-encoding plasmid mediating colistin resistance in salmonella enterica from retail meat in portugal. 201627330063
the emergence and outbreak of multidrug-resistant typhoid fever in china.typhoid fever remains a severe public health problem in developing countries. the emergence of resistant typhoid, particularly multidrug-resistant typhoid infections, highlights the necessity of monitoring the resistance characteristics of this invasive pathogen. in this study, we report a typhoid fever outbreak caused by multidrug-resistant salmonella enterica serovar typhi strains with an acssxtt pattern. resistance genes conferring these phenotypes were harbored by a large conjugative plasmid ...201627329848
antimelanoma effect of salmonella typhimurium integration host factor mutant in murine model.this study aimed to evaluate an attenuated salmonella ihfa-null mutant strain as therapeutic agent to control tumor growth.201627328776
extended-spectrum cephalosporin-resistant salmonella enterica serovar heidelberg strains, the netherlands(1).extended-spectrum cephalosporin-resistant salmonella enterica serovar heidelberg strains (jf6x01.0022/xbai.0251, jf6x01.0326/xbai.1966, jf6x01.0258/xbai.1968, and jf6x01.0045/xbai.1970) have been identified in the united states with pulsed-field gel electrophoresis. our examination of isolates showed introduction of these strains in the netherlands and highlight the need for active surveillance and intervention strategies by public health organizations.201627314180
comparison of microbial communities isolated from feces of asymptomatic salmonella-shedding and non-salmonella shedding dairy cows.in the united states salmonella enterica subsp. enterica serotypes kentucky and cerro are frequently isolated from asymptomatic dairy cows. however, factors that contribute to colonization of the bovine gut by these two serotypes have not been identified. to investigate associations between salmonella status and bacterial diversity, as well as the diversity of the microbial community in the dairy cow hindgut, the bacterial and archaeal communities of fecal samples from cows on a single dairy far ...201627313565
virulence associated genes-deleted salmonella montevideo is attenuated, highly immunogenic and confers protection against virulent challenge in chickens.to construct a novel live vaccine against salmonella enterica serovar montevideo (sm) infection in chickens, two important bacterial regulatory genes, lon and cpxr, which are associated with invasion and virulence, were deleted from the wild type sm genome. attenuated strains, jol1625 (δlon), jol1597 (δcpxr), and jol1599 (δlonδcpxr) were thereby generated. observations with scanning electron microscopy suggested that jol1625 and jol1599 cells showed increased ruffled surface which may be related ...201627785128
multiple-locus variable-number tandem repeat analysis (mlva) for genotyping of salmonella enterica subspecies enterica serotype infantis isolated from human sources.salmonella is an important cause of food-borne infection worldwide. detection of outbreaks caused by salmonella spp. relies on suitable and robust methods for genotyping. little is known about the genetic diversity of the salmonella enterica subspecies enterica serotype infantis strains isolated from human sources in iran. in this study, 40 isolates of s. infantis, which were previously recovered from patients with gastroenteritis or diarrhea in tehran between years 2007 and 2009, were subjected ...201627765620
antagonistic activity of intestinal lactobacteria from domestic fowl against clinical isolates of salmonella enterica.strain parameters of salmonellas and lactobacteria affecting their antagonistic activity were studied using an original method. real-time pcr was applied for measuring the decrease in the concentration of field isolates of salmonellas isolated from chickens in the presence of field isolates of lactobacteria also isolated from the gastrointestinal tract of chickens and broiler chickens. dispersion analysis showed that the probability of suppression of salmonella growth by lactobacteria is determi ...201627783299
typhoid fever in south africa in an endemic hiv setting.typhoid fever remains an important disease in africa, associated with outbreaks and the emerging multidrug resistant salmonella enterica serotype typhi (salmonella typhi) haplotype, h58. this study describes the incidence of, and factors associated with mortality due to, typhoid fever in south africa, where hiv prevalence is high.201627780232
diagnosis of imported ugandan typhoid fever based on local outbreak information: a case report.re-emerging multidrug-resistant typhoid fever is becoming a worldwide threat, especially in east africa. at the beginning of 2015, an outbreak of typhoid fever started in the capital city of uganda, and 1940 suspected cases were reported by 5 march 2015. in this report, we describe a case of typhoid fever caused by a mdr strain with hiv infection and hemoglobin s-syndrome thalassemia in an ugandan from kampala city. it is essential to consider mdr strains of salmonella enterica serovar typhi inf ...201627297635
interferon-γ in salmonella pathogenesis: new tricks for an old dog.salmonella enterica is a facultative intracellular bacterium that is the leading cause of food borne illnesses in humans. the cytokine ifn-γ has well-established antibacterial properties against salmonella and other intracellular microbes, for example its capacity to activate macrophages, promote phagocytosis, and destroy phagocytosed microbes by free radical-driven toxification of phagosomes. but ifn-γ induces the expression of hundreds of uncharacterized genes, suggesting that this cytokine de ...201627773552
ctx-m-14 production by a clinical isolate of the european clone of salmonella enterica 4,[5],12:i. 201627771596
feral pigeons: a reservoir of zoonotic salmonella enteritidis strains?salmonella enterica infections in pigeons are generally associated with pigeon-adapted strains of serovar typhimurium that are of little public health concern. here, we isolated salmonella enteritidis phage type 4 (pt4), an important human pathogen, from a population of feral pigeons in brussels, which was further characterized by pulsed-field gel electrophoresis. all pigeon isolates belonged to the same pulsotype, which has been present in belgian pigeons at least since 2001 and is associated w ...201627771054
urbanized white ibises (eudocimus albus) as carriers of salmonella enterica of significance to public health and wildlife.worldwide, salmonella spp. is a significant cause of disease for both humans and wildlife, with wild birds adapted to urban environments having different opportunities for pathogen exposure, infection, and transmission compared to their natural conspecifics. food provisioning by people may influence these factors, especially when high-density mixed species flocks aggregate. white ibises (eudocimus albus), an iconic everglades species in decline in florida, are becoming increasingly common in urb ...201627768705
isolation and plasmid characterization of carbapenemase (imp-4) producing salmonella enterica typhimurium from cats.carbapenem-resistant enterobacteriaceae (cre) are a pressing public health issue due to limited therapeutic options to treat such infections. cres have been predominantly isolated from humans and environmental samples and they are rarely reported among companion animals. in this study we report on the isolation and plasmid characterization of carbapenemase (imp-4) producing salmonella enterica typhimurium from a companion animal. carbapenemase-producing s. enterica typhimurium carrying blaimp-4 ...201627767038
molecular interaction and cellular location of reca and chew proteins in salmonella enterica during sos response and their implication in swarming.in addition to its role in dna damage repair and recombination, the reca protein, through its interaction with chew, is involved in swarming motility, a form of flagella-dependent movement across surfaces. in order to better understand how sos response modulates swarming, in this work the location of reca and chew proteins within the swarming cells has been studied by using super-resolution microscopy. further, and after in silico docking studies, the specific reca and chew regions associated wi ...201627766091
biofilm formation, phenotypic production of cellulose and gene expression in salmonella enterica decrease under anaerobic conditions.salmonella enterica subsp. enterica is one of the main food-borne pathogens. this microorganism combines an aerobic life outside the host with an anaerobic life within the host. one of the main concerns related to s. enterica is biofilm formation and cellulose production. in this study, biofilm formation, morphotype, cellulose production and transcription of biofilm and quorum sensing-related genes of 11 s. enterica strains were tested under three different conditions: aerobiosis, microaerobiosi ...201627592071
minimal processing of iceberg lettuce has no substantial influence on the survival, attachment and internalization of e. coli o157 and salmonella.the influence of a selection of minimal processing techniques (sanitizing wash prior to packaging, modified atmosphere, storage conditions under light or in the dark) was investigated in relation to the survival of, attachment to and internalization of enteric pathogens in fresh produce. cut iceberg lettuce was chosen as a model for fresh produce, escherichia coli o157:h7 (e. coli o157) and salmonella enterica were chosen as pathogen models. care was taken to simulate industrial post-harvest pro ...201627591385
identification of potential therapeutics to conquer drug resistance in salmonella typhimurium: drug repurposing strategy.salmonella typhimurium is the main cause of gastrointestinal illness in humans, and treatment options are decreasing because drug-resistant strains have emerged.201627761807
identification and characterization of a gene stp17 located on the linear plasmid pbssb1 as an enhanced gene of growth and motility in salmonella enterica serovar typhi.the linear plasmid pbssb1 mediates the flagellar phase variation in h:z66 positive salmonella enterica serovar typhi (s. typhi). the gene named stp17 (s. typhi plasmid number 17 gene) is located on pbssb1 and encodes the protein stp17. the expression pattern at the protein-level and function of stp17 remains unknown. in this study, the recombinant protein stp17his6 was expressed, purified and used to prepare the polyclonal anti-stp17 antibody. we detected protein-level expression of stp17 in s. ...201627761429
spatial dependence of dna damage in bacteria due to low-temperature plasma application as assessed at the single cell level.low temperature plasmas (ltps) generate a cocktail of reactive nitrogen and oxygen species (rnos) with bactericidal activity. the rnos however are spatially unevenly distributed in the plasma. here we test the hypothesis that this distribution will affect the mechanisms underpinning plasma bactericidal activity focussing on the level of dna damage in situ. for the first time, a quantitative, single cell approach was applied to assess the level of dna damage in bacteria as a function of the radia ...201627759098
mapping b-cell responses to salmonella enterica serovars typhimurium and enteritidis in chickens for the discrimination of infected from vaccinated animals.serological surveillance and vaccination are important strategies for controlling infectious diseases of food production animals. however, the compatibility of these strategies is limited by a lack of assays capable of differentiating infected from vaccinated animals (diva tests) for established killed or attenuated vaccines. here, we used next generation phage-display (ngpd) and a 2-proportion z score analysis to identify peptides that were preferentially bound by igy from chickens infected wit ...201627510219
antimicrobial resistance in zoonotic nontyphoidal salmonella: an alarming trend?zoonotic bacteria of the genus salmonella have acquired various antimicrobial resistance properties over the years. the corresponding resistance genes are commonly located on plasmids, transposons, gene cassettes, or variants of the salmonella genomic islands sgi1 and sgi2. human infections by nontyphoidal salmonella isolates mainly result from ingestion of contaminated food. the two predominantly found salmonella enterica subsp. enterica serovars in the usa and in europe are s. enteritidis and ...201627506509
a profile-based method for identifying functional divergence of orthologous genes in bacterial genomes.next generation sequencing technologies have provided us with a wealth of information on genetic variation, but predicting the functional significance of this variation is a difficult task. while many comparative genomics studies have focused on gene flux and large scale changes, relatively little attention has been paid to quantifying the effects of single nucleotide polymorphisms and indels on protein function, particularly in bacterial genomics.201627503221
measurement of the accurate mass of a 50 mda infectious virus.bacteriophage p22 is believed to contain a total of 521 copies of 9 different proteins and a 41,724 base pair genome. despite its enormous size and complexity, phage p22 can be electrosprayed, and it remains intact in ultra-high vacuum where its molar mass distribution has been measured.201627501430
isolation and characterization of antimicrobial-resistant nontyphoidal salmonella enterica serovars from imported food products.the objective of this study was to determine antimicrobial resistance and elucidate the resistance mechanism in nontyphoidal salmonella enterica serovars isolated from food products imported into the united states from 2011 to 2013. food products contaminated with antimicrobial-resistant nontyphoidal s. enterica were mainly imported from taiwan, indonesia, vietnam, and china. pcr, dna sequencing, and plasmid analyses were used to characterize antimicrobial resistance determinants. twentythree of ...201627497122
prevalence and characterization of salmonella enterica and salmonella bacteriophages recovered from beef cattle feedlots in south texas.asymptomatic salmonella carriage in beef cattle is a food safety concern, and the beef feedlot environment may function as a reservoir of this pathogen. the goal of this study was to identify and isolate salmonella and salmonella bacteriophages from beef cattle feedlot environments in order to better understand the microbial ecology of salmonella and identify phages that might be useful as anti-salmonella beef safety interventions. three feedlots in south texas were visited, and 27 distinct samp ...201627497120
rpoe promotes invasion and intracellular survival by regulating spi-1 and spi-2 in salmonella enterica serovar typhi.to demonstrate the role of rpoe during the later stage of hyperosmotic stress in salmonella.201627492279
protective efficacy and immune responses by homologous prime-booster immunizations of a novel inactivated salmonella gallinarum vaccine candidate.salmonella enterica serovar gallinarum (sg) ghost vaccine candidate was recently constructed. in this study, we evaluated various prime-boost vaccination strategies using the candidate strain to optimize immunity and protection efficacy against fowl typhoid.201627489805
characterization and evaluation of a salmonella enterica serotype senftenberg mutant created by deletion of virulence-related genes for use as a live attenuated vaccine.natural infections of chickens with salmonella enterica subsp. enterica serovar senftenberg (s. senftenberg) are characterized by low-level intestinal invasiveness and insignificant production of antibodies. in this study, we investigated the potential effects of lon and cpxr gene deletions on the invasiveness of s senftenberg into the intestinal epithelium of chickens and its ability to induce an immune response, conferring protection against s senftenberg infection. with the allelic exchange m ...201627489135
advances in diagnosis, treatment, and prevention of invasive salmonella infections.typhoidal and nontyphoidal salmonella enterica serotypes are among the most common bacterial causes of acute febrile illnesses in the developing world. in this review, we discuss new advances in understanding of the burden, diagnostic approaches, treatment and vaccines for invasive salmonella infections.201627479027
evaluation of protective immune response against fowl typhoid in chickens vaccinated with the attenuated strain salmonella gallinarum δcobsδcbia.salmonella enterica serovar gallinarum biovar gallinarum (sg) causes fowl typhoid in chickens, a septicemic infection which results in high mortality rates. this disease causes high economic impact to the poultry industry worldwide because of the mortality or elimination of positive flocks to control bacterial dissemination. live vaccines are used in the fields, however the characterization of immune mechanisms important for protection are being studied to improve the efficacy of vaccination sch ...201627473999
identification of salmonella enterica serovar kentucky genes involved in attachment to chicken skin.regardless of sanitation practices implemented to reduce salmonella prevalence in poultry processing plants, the problem continues to be an issue. to gain an understanding of the attachment mechanism of salmonella to broiler skin, a bioluminescent-based mutant screening assay was used. a random mutant library of a field-isolated bioluminescent strain of salmonella enterica serovar kentucky was constructed. mutants' attachment to chicken skin was assessed in 96-well plates containing uniform 6 mm ...201627473153
management of osteomyelitis caused by salmonella enterica subsp. houtenae in a taylor's cantil (agkistrodon bilineatus taylori) using amikacin delivered via osmotic pump.an adult female taylor's cantil (agkistrodon bilineatus taylori) presented with marked spinal and mandibular osteomyelitis that cultured positive for salmonella enterica subsp. houtenae, serovar iv 43:z4,z32:-. progression of osteomyelitis was arrested by treatment using amikacin (0.026 mg/kg per hour) delivered via subcutaneous osmotic pump for 10 mo, replacing the pump every 4 wk. no adverse effects on renal function were appreciated throughout the course of therapy. amikacin therapy was disco ...201627468053
an immuno-magnetic nanobead probe competitive assay for rapid detection of salmonella choleraesuis.a competitive lateral flow assay for the rapid detection of salmonella choleraesuis was developed. immuno-magnetic nanobeads were produced by covalently coupling anti-salmonella choleraesuis antibody to magnetic nanobeads. these immuno-magnetic nanobeads were used as visually detected probes in the subsequent assay. compared with the traditional sandwich assay, which is used for detecting macro-molecules, this new method was developed based on the competitive relationship between s. choleraesuis ...201627455631
the efficacy of an inhibin dna vaccine delivered by attenuated salmonella choleraesuis on follicular development and ovulation responses in crossbred buffaloes.the aim of this study was to evaluate the efficacy of an inhibin dna vaccine delivered by attenuated salmonella choleraesuis on follicular development and ovulation responses in crossbred buffaloes. a total of 158 crossbred buffaloes divided into four groups and were intramuscularly injected with 1×10(10) (t1, n=41), 1×10(9) (t2, n=37), 1×10(8) (t3, n=37) or 0 (c, n=43) cfu/ml bacteria delivered inhibin vaccine in 10ml pbs on day 0 and 14, respectively. all animals were administered with 1000 iu ...201627449408
the crystal structure of the c-terminal domain of the salmonella enterica pduo protein: an old fold with a new heme-binding mode.the two-domain protein pduo, involved in 1,2-propanediol utilization in the pathogenic gram-negative bacterium salmonella enterica is an atp:cob(i)alamin adenosyltransferase, but this is a function of the n-terminal domain alone. the role of its c-terminal domain (pduoc) is, however, unknown. in this study, comparative growth assays with a set of salmonella mutant strains showed that this domain is necessary for effective in vivo catabolism of 1,2-propanediol. it was also shown that isolated, re ...201627446048
prevalence and molecular characterization of salmonella enterica isolates throughout an integrated broiler supply chain in china.a total of 1145 samples were collected from chicken breeder farms, hatcheries, broiler farms, a slaughterhouse and retail refrigerated chicken stores in an integrated broiler supply chain in guangdong province, china, in 2013. one-hundred and two salmonella enterica strains were isolated and subjected to serotyping, antimicrobial susceptibility testing, virulence profile determination and molecular subtyping by pulsed field gel electrophoresis (pfge). the contamination rates in samples from bree ...201627443305
high-resolution ph imaging of living bacterial cells to detect local ph differences.protons are utilized for various biological activities such as energy transduction and cell signaling. for construction of the bacterial flagellum, a type iii export apparatus utilizes atp and proton motive force to drive flagellar protein export, but the energy transduction mechanism remains unclear. here, we have developed a high-resolution ph imaging system to measure local ph differences within living salmonella enterica cells, especially in close proximity to the cytoplasmic membrane and th ...201627923921
interaction between salmonella and schistosomiasis: a review.the interaction between schistosomiasis and salmonella is a particularly important issue in africa, where dual infection by the parasite and the bacterium are likely common. in this review, the ways in which schistosomiasis affects human biology as it relates to salmonella are described. those who are infected by both organisms experience reduced immunological functioning, exhibit irreversible organ damage due to prolonged schistosomiasis infection, and become latent carriers of salmonella enter ...201627907208
antimicrobial susceptibility to azithromycin among salmonella enterica typhi and paratyphi a isolates from india.decreased ciprofloxacin susceptibility (dcs) and multidrug resistance in typhoidal salmonella isolates in areas of endemicity are significant therapeutic problems. guidelines for azithromycin disc diffusion and mic interpretive criteria for salmonella enterica serovar typhi were published recently by the clinical and laboratory standards institute in 2015. we investigated the antimicrobial susceptibility pattern of azithromycin in 100 isolates of salmonella typhi (n=80), paratyphi a (n=18) and b ...201627902389
a comparative evaluation of different diagnostic modalities in the diagnosis of typhoid fever using a composite reference standard: a tertiary hospital based study in central india.enteric fever, caused by salmonella spp. is a major cause of morbidity and mortality worldwide and endemic in many developing countries including india and other south-east asian countries. blood culture is regarded as the gold standard for diagnosis. currently, the standard serological method is tube agglutination with moderate sensitivity and specificity. dot blot assay detecting igm and igg antibodies to a specific 50kd outer membrane protein (omp) antigen of salmonella spp. is a simple, reli ...201627891335
in silico clustering of salmonella global gene expression data reveals novel genes co-regulated with the spi-1 virulence genes through hild.a wide variety of salmonella enterica serovars cause intestinal and systemic infections to humans and animals. salmonella patogenicity island 1 (spi-1) is a chromosomal region containing 39 genes that have crucial virulence roles. the arac-like transcriptional regulator hild, encoded in spi-1, positively controls the expression of the spi-1 genes, as well as of several other virulence genes located outside spi-1. in this study, we applied a clustering method to the global gene expression data of ...201627886269
hyperinvasiveness of salmonella enterica serovar choleraesuis linked to hyperexpression of type iii secretion systems in vitro.salmonella enterica serovars choleraesuis and typhimurium are among the non-typhoid salmonella serovars that are important zoonotic pathogens. in clinical observation, s. typhimurium typically causes diarrheal diseases; however, s. choleraesuis shows high predilection to cause bacteremia. the mechanism why s. choleraesuis is more invasive to humans remains unknown. in this study, we compared the s. typhimurium lt2 and s. choleraesuis sc-b67 proteomes through stable isotope labeling of amino acid ...201627886215
draft genome sequence of salmonella enterica subsp. diarizonae serovar 61:k:1,5,(7) strain crjjgf_00165 (phylum gammaproteobacteria).here, we report a 4.78-mb draft genome sequence of the salmonella enterica subsp. diarizonae serovar 61:k:1,5,(7) strain crjjgf_00165 [also called s. enterica subsp. iiib serovar 61:k:1,5,(7) strain crjjgf_00165], isolated from ground beef in 2007.201627881547
vi capsular polysaccharide: synthesis, virulence, and application.vi capsular polysaccharide, a linear homopolymer of α-1,4-linked n-acetylgalactosaminuronate, is characteristically produced by salmonella enterica serovar typhi. the vi capsule covers the surface of the producing bacteria and serves as an virulence factor via inhibition of complement-mediated killing and promoting resistance against phagocytosis. furthermore, vi also represents a predominant protective antigen and plays a key role in the development of vaccines against typhoid fever. herein, we ...201627869515
salmonella enteritidis effector avra stabilizes intestinal tight junctions via the jnk pathway.salmonella pathogenesis studies to date have focused on salmonella typhimurium, and the pathogenesis of a second major serotype, salmonella enteritidis, is poorly understood. salmonella spp. possess effector proteins that display biochemical activities and modulate host functions. here, we generated a deletion mutant of the effector avra, s.e-avra(-), and a plasmid-mediated complementary strain, s.e-avra(-)/pavra(+) (s.e-avra(+)), in s. enteritidis. using in vitro and in vivo infection models, w ...201627875307
multidrug-resistant outbreak-associated salmonella strains in irrigation water from the metropolitan region, chile.salmonella enterica (s. enterica) is the main cause of foodborne diseases in the chilean population. with the aim of characterizing the presence of s. enterica in bodies of water, samples from 40 sources were obtained, including rivers and irrigation canals used by agricultural farms in the most populated regions of chile. as result, 35 s. enterica isolates belonging to several serotypes were detected, with the highest frequency represented by typhimurium and enteritidis. all strains showed phen ...201627860367
genome sequences of two salmonella enterica serovar kentucky isolates recovered from poultry carcasses in the united states.we report here the draft genome sequences of two salmonella enterica serovar kentucky eburstgroup 15 isolates collected from poultry carcasses in georgia (usa).201627856587
high resolution melting (hrm) analysis as a new tool for rapid identification of salmonella enterica serovar gallinarum biovars pullorum and gallinarum.salmonella enterica serovar gallinarum biovars pullorum and gallinarum represent the most common causative agents of chicken salmonellosis, which result in high mortality and morbidity throughout the world. it is difficult and laborious to discriminate these diseases based on biochemical or phenotypic methods. herein, we report the development of a single nucleotide polymorphism (snp) pcr-high resolution melt (pcr-hrm) assay for the detection and discrimination of both s pullorum and s gallinaru ...201627837117
distribution trends & antibiogram pattern of salmonella enterica serovar newport in india.salmonellosis is a major public health concern worldwide. besides typhoidal salmonellae, infections due to non-typhoidal serovars of salmonella are also associated with high morbidity and mortality leading to huge economic losses. among non-typhoidal serovars, salmonella newport has been reported as a major cause of foodborne infections resulting in outbreaks due to consumption of contaminated food items. little data related to this serovar are available from india leading to the scarcity of inf ...201627834330
the salmonella effector sted mediates march8-dependent ubiquitination of mhc ii molecules and inhibits t cell activation.the spi-2 type iii secretion system (t3ss) of intracellular salmonella enterica translocates effector proteins into mammalian cells. infection of antigen-presenting cells results in spi-2 t3ss-dependent ubiquitination and reduction of surface-localized mature mhc class ii (mmhcii). we identify the effector sted as required and sufficient for this process. in mel juso cells, sted localized to the golgi network and vesicles containing the e3 ubiquitin ligase march8 and mmhcii. sted caused march8-d ...201627832589
molecular characterization of salmonella serovars anatum and ealing associated with two historical outbreaks, linked to contaminated powdered infant formula.powdered infant formula (pif) is not intended to be produced as a sterile product unless explicitly stated and on occasion may become contaminated during production with pathogens such as salmonella enterica. this retrospective study focused on two historically reported salmonellosis outbreaks associated with pif from the united kingdom and france, in 1985 and 1996/1997. in this paper, the molecular characterization of the two outbreaks associated salmonella serovars anatum and ealing is reporte ...201627818652
complete whole-genome sequence of salmonella enterica subsp. enterica serovar java nctc5706.salmonellae are a significant cause of morbidity and mortality globally. here, we report the first complete genome sequence for salmonella enterica subsp. enterica serovar java strain nctc5706. this strain is of historical significance, having been isolated in the pre-antibiotic era and was deposited into the national collection of type cultures in 1939.201627811100
disseminated infections with antibiotic-resistant non-typhoidal salmonella strains: contributions of host and pathogen factors.non-typhoidal salmonella enterica serovars (nts) are generally associated with gastroenteritis; however, the very young and elderly, as well as individuals with compromised immunity, are at risk of developing disseminated infection that can manifest as bacteremia or focal infections at systemic sites. disseminated nts infections can be fatal and are responsible for over 600 000 deaths annually. most of these deaths are in sub-saharan africa, where multidrug-resistant nts clones are currently cir ...201627765795
prevalence of virulence and antimicrobial resistance genes in <i>salmonella</i> spp. isolated from commercial chickens and human clinical isolates from south africa and brazil.salmonellosis is a significant public health concern around the world. the injudicious use of antimicrobial agents in poultry production for treatment, growth promotion and prophylaxis has resulted in the emergence of drug resistant strains of salmonella. the current study was conducted to investigate the prevalence of virulence and antimicrobial resistance genes from salmonella isolated from south african and brazilian broiler chickens as well as human clinical isolates. out of a total of 200 c ...201627796114
bloodstream infection due to ctx-m-15 and tem-1 extended spectrum β-lactamase-producing salmonella enterica serovar virchow st16.a 57-year-old man presented with a high fever and diarrhea. a blood culture showed the presence of a group c nontyphoidal salmonella isolate. on salmonella serotyping, the isolate was salmonella enterica serovar virchow. its sequence type was determined to be st16 by sequence analysis of seven different housekeeping genes. the blactx-m group 1 and blatem genes were amplified by multiplex pcr assays for detecting esbl genes. sequences of both amplicons were respectively identical to ctx-m-15- and ...201627795467
an extended genotyping framework for salmonella enterica serovar typhi, the cause of human typhoid.the population of salmonella enterica serovar typhi (s. typhi), the causative agent of typhoid fever, exhibits limited dna sequence variation, which complicates efforts to rationally discriminate individual isolates. here we utilize data from whole-genome sequences (wgs) of nearly 2,000 isolates sourced from over 60 countries to generate a robust genotyping scheme that is phylogenetically informative and compatible with a range of assays. these data show that, with the exception of the rapidly d ...201627703135
occurrence of mcr-1 in colistin-resistant salmonella enterica isolates recovered from humans and animals in italy, 2012 to 2015. 201627697756
genomic and evolutionary analysis of two salmonella enterica serovar kentucky sequence types isolated from bovine and poultry sources in north america.salmonella enterica subsp. enterica serovar kentucky is frequently isolated from healthy poultry and dairy cows and is occasionally isolated from people with clinical disease. a genomic analysis of 119 isolates collected in the united states from dairy cows, ground beef, poultry and poultry products, and human clinical cases was conducted. results of the analysis demonstrated that the majority of poultry and bovine-associated s. kentucky were sequence type (st) 152. several bovine-associated (n ...201627695032
complete genome sequence of a lytic siphoviridae bacteriophage infecting several serovars of salmonella enterica.the bacteriophage 100268_sal2 was isolated from water buffalo feces in southern italy, exhibiting lytic activity against several subspecies of salmonella enterica this bacteriophage belongs to the siphoviridae family and has a 125,114-bp double-stranded dna (ds-dna) genome containing 188 coding sequences (cdss).201627688334
draft genome sequence of salmonella enterica subsp. enterica serovar orion strain crjjgf_00093 (phylum gammaproteobacteria).here, we report a 4.70-mbp draft genome sequence of salmonella enterica subsp. enterica serovar orion strain crjjgf_00093, isolated from a dog in 2005.201627688320
grad-seq guides the discovery of proq as a major small rna-binding protein.the functional annotation of transcriptomes and identification of noncoding rna (ncrna) classes has been greatly facilitated by the advent of next-generation rna sequencing which, by reading the nucleotide order of transcripts, theoretically allows the rapid profiling of all transcripts in a cell. however, primary sequence per se is a poor predictor of function, as ncrnas dramatically vary in length and structure and often lack identifiable motifs. therefore, to visualize an informative rna land ...201627671629
in vivo cloning of large chromosomal segments into a bac derivative by generalized transduction and recombineering in salmonella enterica.recombineering has been used to facilitate the development of in vivo cloning methods. however, the method relies heavily on pcr, which still generates a much higher error rate than dna replication in vivo, even when amplifying large dna inserts. here, a precise technique is reported in salmonella enterica that enables the cloning of up to at least 19 kb target chromosomal dna segments that had been marked by frts, which were derived from two consecutive lambda red-mediated recombination events. ...201627666751
isolation, identification, and antibiotic susceptibility testing of salmonella from slaughtered bovines and ovines in addis ababa abattoir enterprise, ethiopia: a cross-sectional study.salmonellae are ubiquitous, found in animals, humans, and the environment, a condition which facilitates transmission and cross contamination. salmonella enterica serotypes exert huge health and economic impacts due to their virulence or carriage of antibiotic resistance traits. to address this significant issues with regard to public health, availability of adequate information on the prevalence and antibiotic resistance patterns of salmonella, and establishment of adequate measures to control ...201627660816
draft genome sequences of two salmonella enterica strains isolated from sprouted chia and flax seed powders.a 2014 foodborne salmonellosis outbreak in canada and the united states implicated, for the first time, sprouted chia seed powder as the vehicle of transmission. here, we report the draft whole genome sequences of two salmonella enterica strains isolated from sprouted powders related to the aforementioned outbreak.201627660774
draft genome sequences of 11 salmonella enterica strains with variable levels of barotolerance.the diversity of the genus salmonella is reflected in the physiological adaptations used by its members in response to stressors such as high pressure. here we report the draft whole genome sequences of 11 salmonella enterica strains, five sensitive strains and six demonstrating high levels of pressure resistance.201627660773
molecular surveillance identifies multiple transmissions of typhoid in west africa.the burden of typhoid in sub-saharan african (ssa) countries has been difficult to estimate, in part, due to suboptimal laboratory diagnostics. however, surveillance blood cultures at two sites in nigeria have identified typhoid associated with salmonella enterica serovar typhi (s. typhi) as an important cause of bacteremia in children.201627657909
the effect of phytogenic feed additives to substitute in-feed antibiotics on growth traits and blood biochemical parameters in broiler chicks challenged with salmonella typhimurium.there is a growing concern over the use of antibiotics due to the increased resistance of pathogens in broiler. the present study was designed to find the comparative effect of an antibiotic, and some phytogenic on performance traits, blood biochemical parameters, and antioxidant status during starter phase exposed to salmonella typhimurium challenge. a total of 560-day-old broiler chicks (ross 308) were randomly allocated to seven treatments (eight replicates). control (basal diet); t1, infecte ...201627646442
complete genome sequences of 17 canadian isolates of salmonella enterica subsp. enterica serovar heidelberg from human, animal, and food sources.salmonella enterica subsp. enterica serovar heidelberg is a highly clonal serovar frequently associated with foodborne illness. to facilitate subtyping efforts, we report fully assembled genome sequences of 17 canadian s heidelberg isolates including six pairs of epidemiologically related strains. the plasmid sequences of eight isolates contain several drug resistance genes.201627635008
draft genome sequence of salmonella enterica subsp. enterica serovar bardo strain crjjgf_00099 (phylum gammaproteobacteria).here, we report a 4.87-mbp draft genome sequence of the multidrug-resistant (mdr) salmonella enterica subsp. enterica serovar bardo strain crjjgf_00099, isolated from dairy cattle in 2005.201627634995
cross-reactive multifunctional cd4+ t cell responses against salmonella enterica serovars typhi, paratyphi a and paratyphi b in humans following immunization with live oral typhoid vaccine ty21a.the live oral typhoid vaccine ty21a elicits predominantly cd8+, as well as cd4+ t cells mediated immune responses. clinical field studies showed that ty21a is moderately effective against s. typhi and s. paratyphi b, but not s. paratyphi a infections. in this study we describe the in depth characterization of s. typhi, s. paratyphi a and s. paratyphi b cross-reactive cd4+ t cell responses elicited following immunization with ty21a. pbmc samples were collected from 16 healthy volunteers before an ...201627634430
gyra ser83 and parc trp106 mutations in salmonella enterica serovar typhi isolated from typhoid fever patients in tertiary care hospital.typhoid fever is endemic in india and other developing countries, causing major public health problems with high morbidity and mortality. the resistance of salmonella enterica serovar typhi (s. typhi) towards commonly prescribed antimicrobials is increasing in developing countries. however, there have been several reports of the therapeutic failure of fluoroquinolones in patients with salmonella infection. resistance to quinolones/ fluoroquinolones commonly arises due to target site mutation.201627630841
attachment of salmonella strains to a plant cell wall model is modulated by surface characteristics and not by specific carbohydrate interactions.processing of fresh produce exposes cut surfaces of plant cell walls that then become vulnerable to human foodborne pathogen attachment and contamination, particularly by salmonella enterica. plant cell walls are mainly composed of the polysaccharides cellulose, pectin and hemicelluloses (predominantly xyloglucan). our previous work used bacterial cellulose-based plant cell wall models to study the interaction between salmonella and the various plant cell wall components. we demonstrated that sa ...201627629769
salmonella enterica serotype enteritidis vertebral osteomyelitis and epidural abscess complicated with meningitis.infection with non-typhoidal salmonella often results in a self-limited acute gastroenteritis. extra-intestinal salmonella infection is relatively rare and occurs predominantly in infants and adults with significant underlying conditions. we describe a 54-year-old japanese man with a history of heavy alcohol consumption and daily contact with a dog, who developed bacteremia complicated by vertebral osteomyelitis, spinal epidural abscess, and meningitis, due to salmonella enterica serotype enteri ...201627628612
prevalence, distribution, and diversity of salmonella spp. in meat samples collected from italian slaughterhouses.recently worldwide food safety authorities indicated the rise of foodborne outbreaks linked to salmonella: this highlighted the need to intensify monitoring and apply more targeted controls to help manage the spread of the disease. the aim of this study was to assess the prevalence and distribution of salmonella serotypes in 7 slaughterhouses, located in different areas of naples province (regione campania, italy). meat samples collected from the slaughterhouses were submitted for standardized m ...201627626599
mtmr4 is required for the stability of the salmonella-containing vacuole.the intracellular pathogen salmonella enterica servovar typhimurium (s.typhimurium) modulates the host cell's phosphoinositide (pi) metabolism to establish its intracellular replicative niche, the salmonella-containing vacuole (scv). upon invasion, phosphoinositide 3-phosphate (pi(3)p) and other early endosomal markers are rapidly recruited to and remain associated with the scv throughout its early maturation. while the phosphoinositide 3-phosphatase myotubularin 4 (mtmr4) has an established rol ...201627625994
antimicrobial susceptibility pattern and sequence analysis of dna gyrase and dna topoisomerase iv in salmonella enterica serovars typhi and paratyphi a isolates with decreased susceptibility to ciprofloxacin.we describe the antimicrobial susceptibility pattern of 100 typhoidal salmonella isolates recovered from blood cultures and also investigate the association of decreased ciprofloxacin susceptibility with mutations in the genes coding for dna gyrase and topoisomerase iv in 55 isolates.201627618918
typhoidal salmonellae: use of multi-locus sequence typing to determine population structure.enteric fever is an invasive infection predominantly caused by salmonella enterica serovars typhi and paratyphi a. the pathogens have evolved from other nontyphoidal salmonellaeto become invasive and host restricted. emergence of antimicrobial resistance in typhoidal salmonellae in some countries is a major therapeutic concern as the travelers returning from endemic countries carry resistant strains to non endemic areas. in order to understand the epidemiology and to design disease control strat ...201627618626
zebrafish as a novel model for non-typhoidal salmonella pathogenesis, transmission and vaccine efficacy.salmonella-induced gastroenteritis causes massive morbidity and mortality in both adults and children of developing countries. however, it is difficult to study the mode of infection and vaccine efficacy due to inadequacies of current animal models. for this reason, we have explored using zebrafish as an improved model for non-typhoidal salmonella (nts) infection, including salmonella enterica typhimurium, salmonella enterica enteritidis and salmonella enterica weltevreden. in this study, we fou ...201627614779
draft genome sequence of salmonella enterica subsp. enterica serovar blockley strain crjjgf_00147 (phylum gammaproteobacteria).here, we report a 4.72-mbp draft genome sequence of salmonella enterica subsp. enterica serovar blockley strain crjjgf_00147, isolated from chicken rinse in 2009.201627609923
tolc is important for bacterial survival and oxidative stress response in salmonella enterica serovar choleraesuis in an acidic environment.the outer membrane protein tolc, which is one of the key components of several multidrug efflux pumps, is thought to be involved in various independent systems in enterobacteriaceae. since the acidic environment of the stomach is an important protection barrier against foodborne pathogen infections in hosts, we evaluated whether tolc played a role in the acid tolerance of salmonella enterica serovar choleraesuis. comparison of the acid tolerance of the tolc mutant and the parental wild-type stra ...201627599929
draft genome sequence of salmonella enterica subsp. enterica serovar putten strain crjjgf_00159 (phylum gammaproteobacteria).here, we report a 4.90 mbp draft genome sequence of salmonella enterica subsp. enterica serovar putten strain crjjgf_00159 isolated from food animal in 2004.201627587814
phenotypic and genotypic antimicrobial resistance and virulence genes of salmonella enterica isolated from pet dogs and cats.a total of 122 salmonella isolates from dogs (n=113) and cats (n=9) comprising 32 serotypes were obtained from household dogs (n=250) and cats (n=50) during 2012-2015. the isolates were characterized by serotyping, examining phenotype and genotype of antimicrobial resistance and screening virulence genes. serovars weltevreden (15.6%) and typhimurium (13.9%) were the most common serotypes. the majority of the isolates were multidrug resistant (43%). the dog isolates (12.3%) harbored class 1 integ ...201627586467
wgs for surveillance of antimicrobial resistance: a pilot study to detect the prevalence and mechanism of resistance to azithromycin in a uk population of non-typhoidal salmonella.wgs and phenotypic methods were used to determine the prevalence of azithromycin resistance in salmonella enterica isolates from the uk and to identify the underlying mechanisms of resistance.201627585964
outer membrane vesicles derived from salmonella typhimurium mutants with truncated lps induce cross-protective immune responses against infection of salmonella enterica serovars in the mouse model.salmonella enterica cause diarrheal and systemic diseases and are of considerable concern worldwide. vaccines that are cross-protective against multiple serovars could provide effective control of salmonella-mediated diseases. bacteria-derived outer membrane vesicles (omvs) are highly immunogenic and are capable of eliciting protective immune responses. alterations in lipopolysaccharide (lps) length can result in outer membrane remodeling and composition of outer membrane proteins (omps) changin ...201627578609
a toxin antitoxin system promotes the maintenance of the inca/c-mobilizable salmonella genomic island 1.the multidrug resistance salmonella genomic island 1 (sgi1) is an integrative mobilizable element identified in several enterobacterial pathogens. this chromosomal island requires a conjugative inca/c plasmid to be excised as a circular extrachromosomal form and conjugally mobilized in trans. preliminary observations suggest stable maintenance of sgi1 in the host chromosome but paradoxically also incompatibility between sgi1 and inca/c plasmids. here, using a salmonella enterica serovar agona cl ...201627576575
molecular characterization of extended-spectrum-cephalosporin-resistant enterobacteriaceae from wild kelp gulls in south america.extended-spectrum-cephalosporin-resistant enterobacteriaceae are a public health concern due to limited treatment options. here, we report on the occurrence and the molecular characteristics of extended-spectrum-cephalosporin-resistant enterobacteriaceae recovered from wild birds (kelp gulls). our results revealed kelp gulls as a reservoir of various extended-spectrum cephalosporinase genes associated with different genetic platforms. in addition, we report for the first time the presence of a k ...201627572403
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 c ...201627572160
what's in a name? species-wide whole-genome sequencing resolves invasive and noninvasive lineages of salmonella enterica serotype paratyphi b.for 100 years, it has been obvious that salmonella enterica strains sharing the serotype with the formula 1,4,[5],12:b:1,2-now known as paratyphi b-can cause diseases ranging from serious systemic infections to self-limiting gastroenteritis. despite considerable predicted diversity between strains carrying the common paratyphi b serotype, there remain few methods that subdivide the group into groups that are congruent with their disease phenotypes. paratyphi b therefore represents one of the can ...201627555304
molecular characterization of salmonella enterica serovar aberdeen negative for h2s production in china.salmonella enterica infections continue to be a significant burden on public health worldwide. the ability of s. enterica to produce hydrogen sulfide (h2s) is an important phenotypic characteristic used to screen and identify salmonella with selective medium; however, h2s-negative salmonella have recently emerged. in this study, the h2s phenotype of salmonella isolates was confirmed, and the selected isolates were subjected to antimicrobial susceptibility testing and molecular identification by ...201627552230
single molecule super-resolution imaging of proteins in living salmonella enterica using self-labelling enzymes.the investigation of the subcellular localization, dynamics and interaction of proteins and protein complexes in prokaryotes is complicated by the small size of the cells. super-resolution microscopy (srm) comprise various new techniques that allow light microscopy with a resolution that can be up to ten-fold higher than conventional light microscopy. application of srm techniques to living prokaryotes demands the introduction of suitable fluorescent probes, usually by fusion of proteins of inte ...201627534893
draft genome sequence of blatem-1-mediated cephalosporin-resistant salmonella enterica serovar typhi from bloodstream infection.enteric fever is a major cause of concern in developing countries across the globe. the primary choice of antibiotics remains fluoroquinolones, followed by cephalosporins. resistance to third-generation cephalosporins is rarely reported in salmonella enterica serovar typhi. this study reports the whole genome sequence of an s. typhi isolate resistant to cefixime [minimum inhibitory concentration (mic)=512μg/ml] by microbroth dilution. interestingly, the isolate was negative for the cephalosporin ...201627530999
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