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profile of culture positive enteric fever from bangalore.enteric fever is endemic in india. the aim of this study was to analyse the clinical, laboratory, antibiotic sensitivity profile and response to antibiotics of culture positive enteric fever patients from bangalore.200927408286
epidemiological investigation of an outbreak of enteric fever.ninety five cases of enteric fever among military recruits from a regimental training centre at maharastra were admitted to the local military hospital in a few weeks time.200727408039
reemergence of chloramphenicol sensitivity in enteric fever.enteric fever is a global health problem and rapidly developing resistance to various drugs makes the situation more alarming. drug sensitivity in salmonella enterica serovar typhi and salmonella enterica serovar paratyphi a isolated from 45 blood culture positive cases of enteric fever was tested to determine in-vitro susceptibility pattern of prevalent strains in northern india.200727407999
the target spectrum of sdsr small rna in salmonella.model enteric bacteria such as escherichia coli and salmonella enterica express hundreds of small non-coding rnas (srnas), targets for most of which are yet unknown. some srnas are remarkably well conserved, indicating that they serve cellular functions that go beyond the necessities of a single species. one of these 'core srnas' of largely unknown function is the abundant ∼100-nucleotide sdsr srna which is transcribed by the general stress σ-factor, σ(s) and accumulates in stationary phase. in ...201627407104
lps remodeling triggers formation of outer membrane vesicles in salmonella.outer membrane vesicles (omv) are proposed to mediate multiple functions during pathogenesis and symbiosis. however, the mechanisms responsible for omv formation remain poorly understood. it has been shown in eukaryotic membranes that lipids with an inverted-cone shape favor the formation of positive membrane curvatures. based on these studies, we formulated the hypothesis that lipid a deacylation might impose shape modifications that result in the curvature of the outer membrane (om) and subseq ...201627406567
salmonella effectors ssef and sseg interact with mammalian protein acbd3 (gcp60) to anchor salmonella-containing vacuoles at the golgi network.following infection of mammalian cells, salmonella enterica serovar typhimurium (s typhimurium) replicates within membrane-bound compartments known as salmonella-containing vacuoles (scvs). the salmonella pathogenicity island 2 type iii secretion system (spi-2 t3ss) translocates approximately 30 different effectors across the vacuolar membrane. ssef and sseg are two such effectors that are required for scvs to localize close to the golgi network in infected epithelial cells. in a yeast two-hybri ...201627406559
detection of a novel qnrb19-carrying plasmid variant mediating decreased fluoroquinolone susceptibility in salmonella enterica serovar hadar.thirty salmonella enterica subsp. enterica serovar hadar isolates of avian origin collected between 2007 and 2010 from chicken carcasses in five geographically spread abattoirs in germany were investigated for plasmid-mediated quinolone resistance determinants. four isolates were identified by pcr analysis and hybridization experiments to carry qnrb genes. the isolates were indistinguishable by their xbai macrorestriction patterns and did not exhibit a mutation in the quinolone resistance-determ ...201727404660
a metabolic intermediate of the fructose-asparagine utilization pathway inhibits growth of a salmonella frab mutant.insertions in the salmonella enterica fra locus, which encodes the fructose-asparagine (f-asn) utilization pathway, are highly attenuated in mouse models of inflammation (>1000-fold competitive index). here, we report that f-asn is bacteriostatic to a frab mutant (ic50 19 μm), but not to the wild-type or a fra island deletion mutant. we hypothesized that the presence of frad kinase and absence of frab deglycase causes build-up of a toxic metabolite: 6-phosphofructose-aspartate (6-p-f-asp). we us ...201627403719
mice deficient in angiopoietin-like protein 2 (angptl2) gene show increased susceptibility to bacterial infection due to attenuated macrophage activity.macrophages play crucial roles in combatting infectious disease by promoting inflammation and phagocytosis. angiopoietin-like protein 2 (angptl2) is a secreted factor that induces tissue inflammation by attracting and activating macrophages to produce inflammatory cytokines in chronic inflammation-associated diseases such as obesity-associated metabolic syndrome, atherosclerosis, and rheumatoid arthritis. here, we asked whether and how angptl2 activates macrophages in the innate immune response. ...201627402837
low concentration of salmonella enterica and generic escherichia coli in farm ponds and irrigation distribution systems used for mixed produce production in southern georgia.studies have shown that irrigation water can be a vector for pathogenic bacteria. due to this, the food safety modernization act's (fsma) produce safety rule requires that agricultural water directly applied to produce be safe and of adequate sanitary quality for use, which may pose a challenge for some farmers. the purpose of this research was to assess the presence and concentration of salmonella and generic escherichia coli in irrigation water from distribution systems in a mixed produce prod ...201627400147
incidence and growth of salmonella enterica on the peel and pulp of avocado (persea americana) and custard apple (annona squamosa).the aim of this study was to assess the incidence and to estimate the growth kinetic parameters (maximum growth rate, μ; lag time, λ; and maximum population, κ) of salmonella on the peel and pulp of avocado (perseaamericana var. americana) and custard apple (annona squamosa l.) as affected by temperature (10-30°c). the incidence of salmonella was assessed on the peel and pulp of the fruits (n=200 of each fruit), separately, totalizing 800 analyses. only three samples of custard apple pulp were p ...201627393884
draft genome sequence of salmonella enterica subsp. enterica serovar kiambu strain crjjgf_00061 (phylum gammaproteobacteria).we report a 4.58 mbp draft genome sequence of salmonella enterica subsp. enterica serovar kiambu strain crjjgf_00061 isolated from cattle in 2004.201627389263
salmonella enterica serovar enteritidis brain abscess mimicking meningitis after surgery for glioblastoma multiforme: a case report and review of the literature.salmonella brain abscess associated with brain tumor is rare. only 11 cases have been reported to date. here we report a case of brain abscess caused by salmonella enterica serovar enteritidis mimicking post-surgical meningitis in a patient with glioblastoma multiforme.201627387824
experimental infection of chickens by a flagellated motile strain of salmonella enterica serovar gallinarum biovar gallinarum.salmonella enterica subsp. enterica serovar gallinarum biovar gallinarum (sg) causes fowl typhoid (ft), a septicaemic disease which can result in high mortality in poultry flocks. the absence of flagella in sg is thought to favour systemic invasion, since bacterial recognition via toll-like receptor (tlr)-5 does not take place during the early stages of ft. in the present study, chicks susceptible to ft were inoculated with a wild type sg (sg) or its flagellated motile derivative (sg fla(+)). in ...201627387725
licoflavonol is an inhibitor of the type three secretion system of salmonella enterica serovar typhimurium.as an important food-borne human pathogen, salmonella enterica serovar typhimurium depends on its type iii secretion system (t3ss) as a major virulence factor to cause disease all over the world. the t3ss secretes effector proteins to facilitate invasion into host cells. in this study, twenty prenylated flavonoids (1-20) were screened for their anti-t3ss activity, revealing that several analogs exhibited strong inhibitory effects on the secretion of salmonella pathogenicity island 1 (spi-1)-asso ...201627387231
beneficial effects of sodium phenylbutyrate administration during infection with salmonella enterica serovar typhimurium.sodium phenylbutyrate (pba) is a derivative of the short-chain fatty acid butyrate and is approved for treatment of urea cycle disorders and progressive familial intrahepatic cholestasis type 2. previously known functions include histone deacetylase inhibitor, endoplasmic reticulum stress inhibitor, ammonia sink, and chemical chaperone. here, we show that pba has a previously undiscovered protective role in host mucosal defense during infection. administration of pba to taconic mice resulted in ...201627382022
unstable tandem gene amplification generates heteroresistance (variation in resistance within a population) to colistin in salmonella enterica.heteroresistance, a phenomenon where subpopulations of a bacterial isolate exhibit different susceptibilities to an antibiotic, is a growing clinical problem where the underlying genetic mechanisms in most cases remain unknown. we isolated colistin resistant mutants in escherichia coli and salmonella enterica serovar typhimurium at different concentrations of colistin. genetic analysis showed that genetically stable pmrab point mutations were responsible for colistin resistance during selection ...201627381382
identification of bapa in strains of salmonella enterica subsp. enterica isolated from wild animals kept in captivity in sinaloa, mexico.bapa, previously named stm2689, encodes the bapa protein, which, along with cellulose and fimbriae, constitutes biofilms. biofilms are communities of microorganisms that grow in a matrix of exopolysaccharides and may adhere to living tissues or inert surfaces. biofilm formation is associated with the ability to persist in different environments, which contributes to the pathogenicity of several species. we analyzed the presence of bapa in 83 strains belonging to 17 serovars of salmonella enteric ...201627379195
microbial ecosystem analysis in root canal infections refractory to endodontic treatment.the purpose of this study was to combine multiple displacement amplification and checkerboard dna-dna hybridization to qualitatively and quantitatively evaluate the microbiota present in infections refractory to endodontic treatment.201627377440
in vitro and in vivo probiotic assessment of leuconostoc mesenteroides p45 isolated from pulque, a mexican traditional alcoholic beverage.pulque is a mexican traditional alcoholic, non-distilled, fermented beverage produced by the fermentation of the sap, known as aguamiel, extracted from several maguey (agave) species. pulque has traditionally been considered a healthy beverage due to its nutrient content and also a traditional medicine for the treatment of gastrointestinal disorders and intestinal infections. during pulque fermentation, the development of acidity, alcohol and viscosity define its final sensorial properties, deve ...201627375977
survival of foodborne pathogens in natural cracked olive brines.this work reports the survival (challenge tests) of foodborne pathogen species (escherichia coli, staphylococcus aureus, listeria monocytogenes, and salmonella enterica) in aloreña de málaga table olive brines. the inhibitions were fit using a log-linear model with tail implemented in ginafit excel software. the olive brine had a considerable inhibitory effect on the pathogens. the residual (final) populations (fp) after 24 h was below detection limit (<1.30 log10 cfu/ml) for all species assayed ...201627375250
baer protein acts as an activator of nuclear factor-kappa b and janus kinase 2 to induce inflammation in murine cell lines.baer, a response regulator protein, takes part in multidrug efflux, bacterial virulence activity, and other biological functions. recently, baer was shown to induce inflammatory responses by activating the mitogen-activated protein kinases (mapks). in this study, we investigated additional pathways used by baer to induce an inflammatory response. baer protein was purified from salmonella enterica paratyphi a and subcloned into a pposkj expression vector. raw 264.7 cells were treated with baer, a ...201627374640
clonal persistence of salmonella enterica serovars montevideo, tennessee, and infantis in feed factories.novel molecular techniques applied in biotechnology research have provided sound evidence on clonal persistence of distinct serovars of salmonella in feed factory environments, over long periods of time (months, even years), which can be responsible for repeated in-house contamination of final products. in this study, we examined the possibility of clonal persistence of isolates of three salmonella serovars that have been repeatedly identified in animal feed samples from three feed factories thr ...201627367016
igg subclasses targeting the flagella of salmonella enterica serovar typhimurium can mediate phagocytosis and bacterial killing.invasive non-typhoidal salmonella are a common cause of invasive disease in immuno-compromised individuals and in children. multi-drug resistance poses challenges to disease control, with a critical need for effective vaccines. flagellin is an attractive vaccine candidate due to surface exposure and high epitope copy number, but its potential as a target for opsonophacytic antibodies is unclear. we examined the effect of targeting flagella with different classes of igg on the interaction between ...201627366588
an outbreak of a possibly new salmonella enterica subspecies enterica serovar with the antigenic formula 11:z41:e,n,z15, greece, march to may 2016: preliminary results.eleven salmonella spp. isolates with the antigenic type 11:z41:e,n,z15 - not referred to in the 9th edition of the white-kauffman-le minor scheme - were identified at the national reference laboratory for salmonella in greece. their pulsed-field gel electrophoresis profiles were indistinguishable. no apparent epidemiological link has yet been identified; the results of a case-case study are pending.201627363973
salmosan, a β-galactomannan-rich product, protects epithelial barrier function in caco-2 cells infected by salmonella enterica serovar enteritidis.one promising strategy for reducing human salmonellosis induced by salmonella enteritidis is to supplement animal diets with natural feed additives such as mannan oligosaccharides (moss).201627358412
dectin-2 recognizes mannosylated o-antigens of human opportunistic pathogens and augments lipopolysaccharide activation of myeloid cells.lps consists of a relatively conserved region of lipid a and core oligosaccharide and a highly variable region of o-antigen polysaccharide. whereas lipid a is known to bind to the toll-like receptor 4 (tlr4)-myeloid differentiation factor 2 (md2) complex, the role of the o-antigen remains unclear. here we report a novel molecular interaction between dendritic cell-associated c-type lectin-2 (dectin-2) and mannosylated o-antigen found in a human opportunistic pathogen, hafnia alvei pcm 1223, whic ...201627358401
diverse distribution of toxin-antitoxin ii systems in salmonella enterica serovars.type ii toxin-antitoxin systems (tas), known for their presence in virulent and antibiotic resistant bacterial strains, were recently identified in salmonella enterica isolates. however, the relationships between the presence of tas (ccdab and vapbc) and the epidemiological and genetic features of different non-typhoidal salmonella serovars are largely unknown, reducing our understanding of the ecological success of different serovars. salmonella enterica isolates from different sources, belongi ...201627357537
transfer of salmonella enterica serovar typhimurium from beef to tomato through kitchen equipment and the efficacy of intermediate decontamination procedures.it is well established that a high percentage of foodborne illness is caused by failure of consumers to prepare food in a hygienic manner. indeed, a common practice in households is to use the same kitchen equipment for both raw meat and fresh produce. such a practice may lead to cross-contamination of fruits and vegetables, which are mainly consumed without further processing, with pathogenic microorganisms originating from raw meat. the present study was performed to examine the transfer of th ...201627357047
higher storage temperature causes greater salmonella enterica serovar typhimurium internal penetration of artificially contaminated, commercially available, washed free range eggs.foodborne salmonellosis is a major public health concern, with contaminated eggs identified as a significant source of infection. in australia, the most prevalent cause of salmonellosis from eggs is salmonella enterica subsp. enterica serovar typhimurium. this study explored the effect of temperature after 1, 7, 14, 21, and 28 days of storage on commercially available washed free range eggs, artificially contaminated with salmonella typhimurium on the external surface. at each time point, the ex ...201627357046
biofilm formation and morphotypes of salmonella enterica subsp.arizonae differs from those of other salmonella enterica subspecies in isolates from poultry houses.salmonella serovars are responsible for foodborne diseases around the world. the ability to form biofilms allows microorganisms to survive in the environment. in this study, 73 salmonella strains, belonging to four different subspecies, were isolated from poultry houses and foodstuffs and tested. biofilm formation was measured at four different temperatures and two nutrient concentrations. morphotypes and cellulose production were evaluated at three different temperatures. the presence of severa ...201627357031
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
trna(pro) -mediated downregulation of elongation factor p is required for mgtcbr expression during salmonella infection.bacterial ribosome requires elongation factor p to translate fragments harbouring consecutive proline codons. given the abundance of orfs with potential ef-p regulated sites, ef-p was assumed to be constitutively expressed. here, we report that the intracellular pathogen salmonella enterica serovar typhimurium decreases efp mrna levels during course of infection. we determined that the decrease in efp mrna is triggered by low levels of charged trna(pro) , a condition that salmonella experiences ...201627350030
o-antigen chain-length distribution in salmonella enterica serovar enteritidis is regulated by oxygen availability.lipopolysaccharide (lps) consists of three covalently linked domains: the lipid a, the core region and the o antigen (oag), consisting of repeats of an oligosaccharide. salmonella enterica serovar enteritidis (s. enteritidis) produces a lps with two oag preferred chain lengths: a long (l)-oag controlled by wzzse and a very long (vl)-oag controlled by wzzfepe. in this work, we show that oag produced by s. enteritidis grown in e minimal medium also presented two preferred chain-lengths. however, a ...201627343553
identification of the crp gene in avian pasteurella multocida and evaluation of the effects of crp deletion on its phenotype, virulence and immunogenicity.pasteurella multocida (p. multocida) is an important veterinary pathogen that can cause severe diseases in a wide range of mammals and birds. the global regulator crp gene has been found to regulate the virulence of some bacteria, and crp mutants have been demonstrated to be effective attenuated vaccines against salmonella enterica and yersinia enterocolitica. here, we first characterized the crp gene in p. multocida, and we report the effects of a crp deletion.201627343075
hydrosol of thymbra capitata is a highly efficient biocide against salmonella enterica serovar typhimurium biofilms.salmonella is recognized as one of the most significant enteric foodborne bacterial pathogens. in recent years, the resistance of pathogens to biocides and other environmental stresses, especially when they are embedded in biofilm structures, has led to the search for and development of novel antimicrobial strategies capable of displaying both high efficiency and safety. in this direction, the aims of the present work were to evaluate the antimicrobial activity of hydrosol of the mediterranean s ...201627342550
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
designing, construction and characterization of genetically encoded fret-based nanosensor for real time monitoring of lysine flux in living cells.engineering microorganisms in order to improve the metabolite flux needs a detailed knowledge of the concentrations and flux rates of metabolites and metabolic intermediates in vivo. fluorescence resonance energy transfer (fret) based genetically encoded nanosensors represent a promising tool for measuring the metabolite levels and corresponding rate changes in live cells. here, we report the development of a series of fret based genetically encoded nanosensor for real time measurement of lysine ...201627334743
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
infection susceptibility in gastric intrinsic factor (vitamin b12)-defective mice is subject to maternal influences.mice harboring a mutation in the gene encoding gastric intrinsic factor (gif), a protein essential for the absorption of vitamin b12/cobalamin (cbl), have potential as a model to explore the role of vitamins in infection. the levels of cbl in the blood of gif(tm1a/tm1a) mutant mice were influenced by the maternal genotype, with offspring born to heterozygous (high cbl, f1) mothers exhibiting a significantly higher serum cbl level than those born to homozygous (low cbl, f2) equivalents. low cbl l ...201627329747
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
functional analysis of a type-i ribosome inactivating protein balsamin from momordica balsamina with anti-microbial and dnase activity.ribosome inactivating proteins (rips) have received considerable attention in biomedical research because of their unique activities towards tumor and virus-infected cells. we extracted balsamin, a type-i rip, from momordica balsamina. in the present study, a detailed investigation on dnase activity, antioxidant capacity and antibacterial activity was conducted using purified balsamin. dnase-like activity of balsamin towards plasmid dna was ph, incubation time and temperature dependent. moreover ...201627319013
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
host-mediated sugar oxidation promotes post-antibiotic pathogen expansion.changes in the gut microbiota may underpin many human diseases, but the mechanisms that are responsible for altering microbial communities remain poorly understood. antibiotic usage elevates the risk of contracting gastroenteritis caused by salmonella enterica serovars, increases the duration for which patients shed the pathogen in their faeces, and may on occasion produce a bacteriologic and symptomatic relapse. these antibiotic-induced changes in the gut microbiota can be studied in mice, in w ...201627309805
convergent synthesis of oligosaccharide fragments corresponding to the cell wall o-polysaccharide of salmonella enterica o53.conventional glycoconjugate vaccines are prepared with polysaccharides isolated from bacterial fermentation, an approach with some significant drawbacks such as handling of live bacterial strains, the presence of biological impurities, and inter-batch variations in oligosaccharide epitope structure. however, it has been shown in many cases that a synthetic fragment of appropriate structure conjugated to a protein can be an effective vaccine that circumvents the shortcomings of using full-length ...201527308202
intranasal immunization with a peptide conjugated to salmonella flagellin induces both systemic and mucosal peptide-specific antibody responses in mice.in this study, the mucosal adjuvant activity of salmonella flagellin as a carrier in a conjugate of exp153-rflic was investigated. exp153-rflic was made by conjugation of a synthetic b-cell epitope peptide derived from plasmodium falciparum exported protein-1(exp153) to recombinant phase 1 flagellin of salmonella enterica serovar typhimurium expressed in escherichia coli (rflic), and used to immunize balb/c mice via intranasal instillation. it was found that robust exp153-specific serum igg anti ...201627301339
heterologous expression of der homologs in an escherichia coli der mutant and their functional complementation.the unique escherichia coli gtpase der (double era-like gtpase), which contains tandemly repeated gtp-binding domains, has been shown to play an essential role in 50s ribosomal subunit biogenesis. the depletion of der results in the accumulation of precursors of 50s ribosomal subunits that are structurally unstable at low mg(2+) concentrations. der homologs are ubiquitously found in eubacteria. conversely, very few are conserved in eukaryotes, and none is conserved in archaea. in the present stu ...201627297882
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
transfer of pathogens from cantaloupe rind to preparation surfaces and edible tissue as a function of cutting method.whole and cut cantaloupes have been implicated as vehicles in foodborne illness outbreaks of norovirus, salmonellosis, and listeriosis. preparation methods that minimize pathogen transfer from external surfaces to the edible tissue are needed. two preparation methods were compared for the transfer of listeria monocytogenes, salmonella enterica serovar typhimurium lt2, murine norovirus, and tulane virus from inoculated cantaloupe rinds to edible tissue and preparation surfaces. for the first meth ...201627296423
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
proteomic analysis of egg white heparin-binding proteins: towards the identification of natural antibacterial molecules.the chicken egg resists most environmental microbes suggesting that it potentially contains efficient antimicrobial molecules. considering that some heparin-binding proteins in mammals are antibacterial, we investigated the presence and the antimicrobial activity of heparin-binding proteins from chicken egg white. mass spectrometry analysis of the proteins recovered after heparin-affinity chromatography, revealed 20 proteins, including known antimicrobial proteins (avidin, lysozyme, tenp, ovalbu ...201627294500
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
acidic ph sensing in the bacterial cytoplasm is required for salmonella virulence.ph regulates gene expression, biochemical activities and cellular behaviors. a mildly acidic ph activates the master virulence regulatory system phop/phoq in the facultative intracellular pathogen salmonella enterica serovar typhimurium. the sensor phoq harbors an extracytoplasmic domain implicated in signal sensing, and a cytoplasmic domain controlling activation of the regulator phop. we now report that, surprisingly, a decrease in salmonella's own cytoplasmic ph induces transcription of phop- ...201627282333
salmonella mitigates oxidative stress and thrives in the inflamed gut by evading calprotectin-mediated manganese sequestration.neutrophils hinder bacterial growth by a variety of antimicrobial mechanisms, including the production of reactive oxygen species and the secretion of proteins that sequester nutrients essential to microbes. a major player in this process is calprotectin, a host protein that exerts antimicrobial activity by chelating zinc and manganese. here we show that the intestinal pathogen salmonella enterica serovar typhimurium uses specialized metal transporters to evade calprotectin sequestration of mang ...201627281571
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
early onset neonatal sepsis due to salmonella enterica serovar 4,5,12:i:-: a case report with literature review.the authors report a case of a 36-week male infant born via spontaneous vaginal delivery who developed salmonella sepsis at hrh princess maha chakri sirindhorn medical center srinakharinwirot university, nakhon nayok, thailand. he was born to a mother without identifiable risk factors. on day 3, he developed fever tachycardia, lethargy, poor feeding and diarrhea prompting a sepsis evaluation. blood and stool cultures were positive for s. enterica serovar 4,5,12:i:-. therefore, salmonella infecti ...201527276847
the smul_1544 gene product governs norcobamide biosynthesis in the tetrachloroethene-respiring bacterium sulfurospirillum multivorans.the tetrachloroethene (pce)-respiring bacterium sulfurospirillum multivorans produces a unique cobamide, namely, norpseudo-b12, which, in comparison to other cobamides, e.g., cobalamin and pseudo-b12, lacks the methyl group in the linker moiety of the nucleotide loop. in this study, the protein smul_1544 was shown to be responsible for the formation of the unusual linker moiety, which is most probably derived from ethanolamine-phosphate (ea-p) as the precursor. the product of the smul_1544 gene ...201627274028
structural flexibility of the periplasmic protein, flga, regulates flagellar p-ring assembly in salmonella enterica.a periplasmic flagellar chaperone protein, flga, is required for p-ring assembly in bacterial flagella of taxa such as salmonella enterica or escherichia coli. the mechanism of chaperone-mediated p-ring formation is poorly understood. here we present the open and closed crystal structures of flga from salmonella enterica serovar typhimurium, grown under different crystallization conditions. an intramolecular disulfide cross-linked form of flga caused a dominant negative effect on motility of the ...201627273476
adding biotic complexity alters the metabolic benefits of mutualism.mutualism is ubiquitous in nature and plays an integral role in most communities. to predict the eco-evolutionary dynamics of mutualism it is critical to extend classic pair-wise analysis to include additional species. we investigated the effect of adding a third species to a pair-wise mutualism in a spatially structured environment. we tested the hypotheses that selection for costly excretions in a focal population (i) decreases when an exploiter is added (ii) increases when a third mutualist i ...201627272242
aneurysm of the cranial mesenteric artery as a site of carriage of salmonella enterica subsp. enterica serovar abortusequi in the horse.salmonella enterica subsp. enterica serovar abortusequi is a pathogen restricted to horses. our investigation targeted 4 draft horses (9-10 months old) kept on a japanese farm that had suffered an outbreak of s. abortusequi abortion. the 4 horses were suspected to be carriers of the bacterium owing to their high agglutination titers (≥1:2,560) in tube agglutination testing. the owners' on-farm observations confirmed that the horses had no apparent abnormalities, and s. abortusequi was not isolat ...201627271985
salmonella enterica isolates from layer farm environments are able to form biofilm on eggshell surfaces.this study examined the eggshell biofilm forming ability of salmonella enterica isolates recovered from egg farms. multicellular behaviour and biofilm production were examined at 22 and 37°c by congo red morphology and the crystal violet staining assay. the results indicated that the biofilm forming behaviour of salmonella isolates was dependent on temperature and associated with serovars. significantly greater biofilm production was observed at 22°c compared with 37°c. the number of viable biof ...201627268931
dynamics of antagonistic potency of rhodobacter capsulatus pg lipopolysaccharide against endotoxin-induced effects.the dynamics of antagonistic potency of lipopolysaccharide (lps) isolated from rhodobacter capsulatus pg on the synthesis of proinflammatory (tnf-α, il-1β, il-8, il-6, ifn-γ) and antiinflammatory (il-10, il-1ra) cytokines induced by highly stimulatory endotoxins from escherichia coli or salmonella enterica have been studied. using human whole blood, we have shown that r. capsulatus pg lps inhibited most pronouncedly the endotoxin-induced synthesis of tnf-α, il-1β, il-8, and il-6 during the first ...201627262197
the impact of oxygen on bacterial enteric pathogens.bacterial enteric pathogens are responsible for a tremendous amount of foodborne illnesses every year through the consumption of contaminated food products. during their transit from contaminated food sources to the host gastrointestinal tract, these pathogens are exposed and must adapt to fluctuating oxygen levels to successfully colonize the host and cause diseases. however, the majority of enteric infection research has been conducted under aerobic conditions. to raise awareness of the import ...201627261784
a modular, tn7-based system for making bioluminescent or fluorescent salmonella and escherichia coli strains.our goal was to develop a robust tagging method that can be used to track bacterial strains in vivo to address this challenge, we adapted two existing systems: a modular plasmid-based reporter system (pcs26) that has been used for high-throughput gene expression studies in salmonella and escherichia coli and tn7 transposition. we generated kanamycin- and chloramphenicol-resistant versions of pcs26 with bacterial luciferase, green fluorescent protein (gfp), and mcherry reporters under the control ...201627260360
spi-9 of salmonella enterica serovar typhi is constituted by an operon positively regulated by rpos and contributes to adherence to epithelial cells in culture.the genomic island 9 (spi-9) from salmonella enterica serovar typhi (s. typhi) carries three orfs (sty2876, sty2877, sty2878) presenting 98 % identity with a type 1 secretory apparatus (t1ss), and a single orf (sty2875) similar to a large rtx-like protein exhibiting repeated ig domains. bapa, the salmonella enterica serovar enteritidis orthologous to s. typhi sty2875, has been associated with biofilm formation, and is described as a virulence factor in mice. preliminary in silico analyses reveal ...201627260307
complete and closed genome sequences of 10 salmonella enterica subsp. enterica serovar anatum isolates from human and bovine sources.salmonella enterica is an important pathogen transmitted by numerous vectors. genomic comparisons of salmonella strains from disparate hosts have the potential to further our understanding of mechanisms underlying host specificities and virulence. here, we present the closed genome and plasmid sequences of 10 salmonella enterica subsp. enterica serovar anatum isolates from bovine and human sources.201627257192
small molecule restores itaconate sensitivity in salmonella enterica: a potential new approach to treating bacterial infections.in the context of increasing global antibiotic resistance, the need for alternative therapeutic targets is great. although new antibiotics and resistance inhibitors provide temporary solutions, they are bound to become obsolete. in this work, we propose a new approach, coined "bacterio-modulation" that aims to restore macrophage potency towards bacterial strains that are able to survive in phagolysosomes. one key defense in the macrophage's arsenal is itaconate, an endogenous molecule with antim ...201627254798
serotype epidemiology and multidrug resistance patterns of salmonella enterica infecting humans in italy.salmonella enterica is the zoonotic agent most frequently responsible for foodborne infections in humans worldwide. in this work the presence of s. enterica was investigated in 734 unique enteropathogenic isolates collected from human patients between 2011 and 2012.201627252785
systemic concentrations of short chain fatty acids are elevated in salmonellosis and exacerbation of familial mediterranean fever.gut microbiota-produced short chain fatty acids (scfas) play an important role in the normal human metabolism and physiology. although the gradients of scfas from the large intestine, where they are largely produced, to the peripheral blood as well as the main routes of scfa metabolism by different organs are known well for the healthy state, there is a paucity of information regarding how these are affected in disease. in particular, how the inflammation caused by infection or autoinflammatory ...201627252692
prevalence of virulence and antimicrobial resistance genes in salmonella 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 ...201627247072
the bacterial ipra gene is conserved across enterobacteriaceae, is involved in oxidative stress resistance, and influences gene expression in salmonella enterica serovar typhimurium.the ipra gene (formerly known as yaiv or stm0374) is located in a two-gene operon in the salmonella enterica serovar typhimurium genome and is associated with altered expression during spaceflight and rotating-wall-vessel culture conditions that increase virulence. however, ipra is uncharacterized in the literature. in this report, we present the first targeted characterization of this gene, which revealed that ipra is highly conserved across enterobacteriaceae we found that s typhimurium, esche ...201627246569
phenotypic and genetic changes in the life cycle of small colony variants of salmonella enterica serotype typhimurium induced by streptomycin.small colony variants (scvs), constituting a slow-growing subpopulation of bacteria that facilitates persistence in lethal environmental conditions, are able to revert to the phenotype of rapid growth for further proliferation and transmission. salmonella enterica serotype typhimurium is one of the most important foodborne pathogens. this study investigated the genetic mechanisms how scvs induced by streptomycin reverted to the fast-growing phenotype and the phenotypic changes of scvs among thei ...201627245674
horizontal acquisition of a multidrug-resistance module (r-type assut) is responsible for the monophasic phenotype in a widespread clone of salmonella serovar 4,[5],12:i:.salmonella enterica serovar 4,[5],12:i:- is a monophasic variant of s. typhimurium incapable of expressing the second-phase flagellar antigen (fljab operon), and it is recognized to be one of the most prevalent serovars causing human infections. a clonal lineage characterized by phage type dt193, pulsenet pfge profile stymxb.0131 and multidrug resistance to ampicillin, streptomycin, sulphonamides and tetracycline (r-type assut) is commonly circulating in europe. in this study we determined the d ...201627242707
qnrs1- and aac(6')-ib-cr-producing escherichia coli among isolates from animals of different sources: susceptibility and genomic characterization.salmonella enterica and escherichia coli can inhabit humans and animals from multiple origins. these bacteria are often associated with gastroenteritis in animals, being a frequent cause of resistant zoonotic infections. in fact, bacteria from animals can be transmitted to humans through the food chain and direct contact. in this study, we aimed to assess the antibiotic susceptibility of a collection of s. enterica and e. coli recovered from animals of different sources, performing a genomic com ...201627242699
roles of two ryhb paralogs in the physiology of salmonella enterica.salmonella has evolved complicated regulatory systems to regulate the expression of virulence determinants that are acquired by horizontal gene transfer in response to various environmental niches. among these, small rna (srna)-mediated regulation exhibits unique features, distinct from those of protein factor-mediated regulation, which may provide benefits for a pathogen coping with the complex stress conditions encountered during host infection. specifically, iron acquisition by this pathogeni ...201727242152
cellulolytic potential of probiotic bacillus subtilis ams6 isolated from traditional fermented soybean (churpi): an in-vitro study with regards to application as an animal feed additive.the aim of the present study is to evaluate the probiotic attributes of bacillus subtilis ams6 isolated from fermented soybean (churpi). this isolate exhibited tolerance to low ph (ph 2.0) and bile salt (0.3%), capability to autoaggregate and coaggregate. ams6 also showed highest antibacterial activity against the pathogenic indicator strain salmonella enterica typhimurium (mtcc 1252) and susceptibility towards different antibiotics tested. the isolate was effective in inhibiting the adherence o ...201727242144
engineering of a live salmonella enterica serovar choleraesuis negative-marker strain that allows serological differentiation between immunised and infected animals.the usefulness of salmonella vaccine vehicles is limited by the fact that control programmes relying on salmonella bacteriology and serology cannot differentiate infected animals from vaccinated ones, an ability referred to as diva (differentiating infected from vaccinated animals). as a first step towards salmonella-based diva vaccines, the ompa gene was deleted in live attenuated δphop and δrpos vaccine strains. the ompa gene is present in all salmonella enterica serovars and it encodes an abu ...201627240916
new high-cloning-efficiency vectors for complementation studies and recombinant protein overproduction in escherichia coli and salmonella enterica.galloway et al. recently described a method to alter vectors to include type iis restriction enzymes for high efficiency cloning. utilizing this method, the multiple cloning sites of complementation and overexpression vectors commonly used in our laboratory were altered to contain recognition sequences of the type iis restriction enzyme, bspqi. use of this enzyme increased the rate of cloning success to >97% efficiency. l(+)-arabinose-inducible complementation vectors and overexpression vectors ...201627234933
inhibition of nuclear transport of nf-ĸb p65 by the salmonella type iii secretion system effector spvd.salmonella enterica replicates in macrophages through the action of effector proteins translocated across the vacuolar membrane by a type iii secretion system (t3ss). here we show that the spi-2 t3ss effector spvd suppresses proinflammatory immune responses. spvd prevented activation of an nf-ĸb-dependent promoter and caused nuclear accumulation of importin-α, which is required for nuclear import of p65. spvd interacted specifically with the exportin xpo2, which mediates nuclear-cytoplasmic recy ...201627232334
genetically similar isolates of salmonella enterica serotype enteritidis persistent in china for a long-term period.salmonella enterica serotype enteritidis (s. enteritidis) is an important causative agent of nontyphoidal salmonellosis in human populations. in this study, we collected 72 s. enteritidis strains from 2004 to 2014 in ningbo, mid-east china. of the 72 strains, we identified a dominant clone of 58 strains recovered from patient's feces (n = 48), blood (n = 1), pleural effusion (n = 1), chickens (n = 3), and dessert cakes (n = 5) by pulsed-field gel electrophoresis (pfge) and variable-number of tan ...201627228342
investigating salmonella eko from various sources in nigeria by whole genome sequencing to identify the source of human infections.twenty-six salmonella enterica serovar eko isolated from various sources in nigeria were investigated by whole genome sequencing to identify the source of human infections. diversity among the isolates was observed and camel and cattle were identified as the primary reservoirs and the most likely source of the human infections.201627228329
tiny turtles purchased at pet stores are a potential high risk for salmonella human infection in the valencian region, eastern spain.turtles may be considered unsafe pets, particularly in households with children. this study aimed to assess salmonella carriage by turtles in pet stores and in private ownership to inform the public of the potential health risk, enabling informed choices around pet selection. during the period between september and october 2013, 24 pet stores and 96 private owners were sampled in the valencian region (eastern spain). salmonella identification procedure was based on iso 6579: 2002 recommendations ...201627228194
chronic bacterial pathogens: mechanisms of persistence.many bacterial pathogens can cause acute infections that are cleared with the onset of adaptive immunity, but a subset of these pathogens can establish persistent, and sometimes lifelong, infections. while bacteria that cause chronic infections are phylogenetically diverse, they share common features in their interactions with the host that enable a protracted period of colonization. this article will compare the persistence strategies of two chronic pathogens from the proteobacteria, brucella a ...201627227304
unique lipid anchor attaches vi antigen capsule to the surface of salmonella enterica serovar typhi.polysaccharide capsules are surface structures that are critical for the virulence of many gram-negative pathogenic bacteria. salmonella enterica serovar typhi is the etiological agent of typhoid fever. it produces a capsular polysaccharide known as "vi antigen," which is composed of nonstoichiometrically o-acetylated α-1,4-linked n-acetylgalactosaminuronic acid residues. this glycan is a component of currently available vaccines. the genetic locus for vi antigen production is also present in so ...201627226298
genomic and phenotypic analyses reveal the emergence of an atypical salmonella enterica serovar senftenberg variant in china.human infections with salmonella enterica subspecies enterica serovar senftenberg are often associated with exposure to poultry flocks, farm environments, or contaminated food. the recent emergence of multidrug-resistant isolates has raised public health concerns. in this study, comparative genomics and phenotypic analysis were used to characterize 14 salmonella senftenberg clinical isolates recovered from multiple outbreaks in shenzhen and shanghai, china, between 2002 and 2011. single-nucleoti ...201627225410
images in clinical medicine. salmonella enterica aortitis. 201627223163
poor biofilm-forming ability and long-term survival of invasive salmonella typhimurium st313.salmonella enterica serovar typhimurium, an enteric pathogen that causes a self-limiting gastroenteritis, forms biofilms on different surfaces. in sub-saharan africa, salmonella typhimurium of a novel sequence type (st) 313 was identified and produces septicemia in the absence of gastroenteritis. no animal reservoir has been identified, and it is hypothesized that transmission occurs via human to human. in this study, we show that invasive salmonella typhimurium st313 strains from mali are poor ...201627222487
revisit of fluoroquinolone and azithromycin susceptibility breakpoints for salmonella enterica serovar typhi.in recent years, increase in occurrence of fluoroquinolone (fq)-resistant s almonella typhi isolates has caused considerable inconvenience in selecting appropriate antimicrobials for treatment of typhoid. the world health organization (who) recommends azithromycin for the empirical treatment option of uncomplicated typhoid. the clsi updated the breakpoints of disc diffusion (dd) and mic results of fqs and azithromycin for salmonella typhi in 2015, but dd breakpoints of ofloxacin and levofloxacin ...201627221661
interferon-driven alterations of the host's amino acid metabolism in the pathogenesis of typhoid fever.enteric fever, caused by salmonella enterica serovar typhi, is an important public health problem in resource-limited settings and, despite decades of research, human responses to the infection are poorly understood. in 41 healthy adults experimentally infected with wild-type s. typhi, we detected significant cytokine responses within 12 h of bacterial ingestion. these early responses did not correlate with subsequent clinical disease outcomes and likely indicate initial host-pathogen interactio ...201627217537
heat resistance of salmonella enterica is increased by pre-adaptation to peanut oil or sub-lethal heat exposure.cross-protection represents a considerable challenge in the food industry where hurdled interventions are often employed to reduce salmonella contamination. the heat resistance of salmonella strains from five serotypes (i.e., typhimurium, enteritidis, tennessee, thompson and hartford) at 70 °c was determined by measurement of viable cell populations before and after adaptation to two common stresses employed in low-water activity food processing, desiccation and sub-lethal heat treatment. surviv ...201627217370
effects of citrox and chitosan on the survival of escherichia coli o157:h7 and salmonella enterica in vacuum-packaged turkey meat.in this study, we examined the antimicrobial effects of citrus extract (citrox(®)) and chitosan on lactic acid bacteria (lab) and the pathogens escherichia coli o157:h7 and salmonella enterica on turkey meat during storage under vacuum packaging (vp) at 4 and 10 °c. we also examined the effects of citrox and chitosan on pathogen contamination in tryptic soy broth (tsb). chitosan alone or in combination with citrox inhibited the growth of endogenous lab in turkey meat, whereas citrus extract did ...201627217368
modeling the long-term kinetics of salmonella survival on dry pet food.due to multiple outbreaks and large-scale product recalls, salmonella has emerged as a priority pathogen in dry pet food and treats. however, little data are available to quantify risks posed by these classes of products to both pets and their owners. specifically, the kinetics of salmonella survival on complex pet food matrices are not available. this study measured the long-term kinetics of salmonella survival on a dry pet food under storage conditions commonly encountered during production, r ...201627217351
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