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complete genome sequence of salmonella enterica subsp. enterica serovar thompson strain rm6836.salmonella enterica subsp. enterica serovar thompson strain rm6836 was isolated from lettuce in 2002. we report here the complete sequence and annotation of the genome of s. thompson rm6836. this is the first reported complete genome sequence for s. thompson and it will enhance our understanding of this serovar and provide another point for comparative studies between salmonella enterica strains.201324233585
[putative temperature sensitive riboswitchers in salmonella genome].currently, a number of structurally and functionally different temperature-sensitive elements like as rna thermometers which control a variety of biological processes of bacteria, including virulence, are known. well-known rna thermometers correspond to one long step-loop structure or few hairpins which can be matched or mismatched. based on the computer and thermodynamical analysis of 25 isolates of salmonella enterica with complete genome, algorithm and the criteria of search for putative rna ...201324228493
crispr-mvlst subtyping of salmonella enterica subsp. enterica serovars typhimurium and heidelberg and application in identifying outbreak isolates.salmonella enterica subsp. enterica serovars typhimurium (s. typhimurium) and heidelberg (s. heidelberg) are major causes of foodborne salmonellosis, accounting for a fifth of all annual salmonellosis cases in the united states. rapid, efficient and accurate methods for identification are required for routine surveillance and to track specific strains during outbreaks. we used pulsed-field gel electrophoresis (pfge) and a recently developed molecular subtyping approach termed crispr-mvlst that e ...201324219629
prevalence and characterization of salmonella enterica from the feces of cattle, poultry, swine and hedgehogs in burkina faso and their comparison to human salmonella isolates.production and wild animals are major sources of human salmonellosis and animals raised for food also play an important role in transmission of antimicrobial resistant salmonella strains to humans. furthermore, in sub-saharan africa non-typhoidal salmonella serotypes are common bloodstream isolates in febrile patients. yet, little is known about the environmental reservoirs and predominant modes of transmission of these pathogens. the purpose of this study was to discover potential sources and d ...201324215206
salmonella enterica serotype paratyphi a carrying ctx-m-15 type extended-spectrum beta-lactamase isolated from a japanese traveller returning from india, japan, july 2013.emerging drug resistance in salmonella typhi and s. paratyphi is a substantial public health concern. we report what appears to be the first case and isolation of multidrug resistant s. paratyphi a carrying ctxm-15-type extended-spectrum beta-lactamase from a japanese traveller returning from india.201324256887
genomic characterisation of invasive non-typhoidal salmonella enterica subspecies enterica serovar bovismorbificans isolates from malawi.invasive non-typhoidal salmonella (ints) are an important cause of bacteraemia in children and hiv-infected adults in sub-saharan africa. previous research has shown that ints strains exhibit a pattern of gene loss that resembles that of host adapted serovars such as salmonella typhi and paratyphi a. salmonella enterica serovar bovismorbificans was a common serovar in malawi between 1997 and 2004.201324244782
interaction of phytophagous insects with salmonella enterica on plants and enhanced persistence of the pathogen with macrosteles quadrilineatus infestation or frankliniella occidentalis feeding.recently, most foodborne illness outbreaks of salmonellosis have been caused by consumption of contaminated fresh produce. yet, the mechanisms that allow the human pathogen salmonella enterica to contaminate and grow in plant environments remain poorly described. we examined the effect of feeding by phytophagous insects on survival of s. enterica on lettuce. larger s. enterica populations were found on leaves infested with macrosteles quadrilineatus. in contrast, pathogen populations among plant ...201324205384
analysis of triclosan-selected salmonella enterica mutants of eight serovars revealed increased aminoglycoside susceptibility and reduced growth rates.the biocide triclosan (trc) is used in a wide range of household, personal care, veterinary, industrial and medical products to control microbial growth. this extended use raises concerns about a possible association between the application of triclosan and the development of antibiotic resistance. in the present study we determined triclosan mutant prevention concentrations (mpc) for salmonella enterica isolates of eight serovars and investigated selected mutants for their mechanisms mediating ...201324205194
evaluation of vaccine candidate potential of deltaaroa, deltahtra and deltaaroadeltahtra mutants of salmonella enterica subspecies enterica serovar abortusequi in guinea pigs.salmonella enterica subspecies enterica serovar abortusequi (s. abortusequi), a host adapted salmonella causes abortions, still births and foal mortality in equids. though known since more than 100 years, it is still a problem in many of the developing countries including india. there is dearth of really good vaccine affording immunity lasting at least for one full gestation. in search of a potential vaccine candidate, three defined deletion mutants (deltaaroa, deltahtra and deltaaroadeltahtra) ...201324195347
salmonella enterica serotype arizonae meningitis in a neonate.typhoidal and nontyphoidal salmonella infections are common causes of gastroenteritis in the community. however, salmonella only rarely causes invasive infections like meningitis. we report a 13-day-old female neonate with signs and symptoms of meningitis whose cerebrospinal fluid (csf) culture showed salmonella enterica serotype arizonae that was sensitive to ceftriaxone. she presented with fever and failure to feed for 2 days. despite prompt treatment with ampicillin, gentamicin, and ceftriaxo ...201324187642
dynamics of spread of salmonella enterica in the systemic compartment.traditional microbiological and immunological tools, combined with modern imaging, and molecular and mathematical approaches, have revealed the dispersive nature of salmonella infections. bacterial escape from infected cells, spread in the tissues and attempts to restrain this process by the host give rise to fascinating scenarios that underpin the pathogenesis of salmonelloses.201324183878
phylogenetic diversity of the enteric pathogen salmonella enterica subsp. enterica inferred from genome-wide reference-free snp characters.the enteric pathogen salmonella enterica is one of the leading causes of foodborne illness in the world. the species is extremely diverse, containing more than 2,500 named serovars that are designated for their unique antigen characters and pathogenicity profiles-some are known to be virulent pathogens, while others are not. questions regarding the evolution of pathogenicity, significance of antigen characters, diversity of clustered regularly interspaced short palindromic repeat (crispr) loci, ...201324158624
isolation of salmonella virchow from a fruit bat (pteropus giganteus).detection of zoonotic pathogens carried by bats is important both for understanding disease ecology and for developing preventive measures. pteropus fruit bats have been identified as potential carriers of salmonella enterica serotype typhi. a cross-sectional study was conducted to determine the prevalence of salmonella typhi and other salmonella serotypes in pteropus giganteus fruit bats in bangladesh. rectal swabs were collected from 302 bats and cultured for salmonella species. the bats were ...201324136382
occurrence of extended-spectrum β-lactamases among isolates of salmonella enterica subsp. enterica from food-producing animals and food products, in portugal.a total of 1120 salmonella spp. isolates, recovered from poultry, swine and food products of animal origin (bovine, swine and poultry) over the period of 2009-2011, were investigated in order to determine their serotype, susceptibility to a panel of eleven antimicrobials (a, ampicillin; ct, cefotaxime; cp, ciprofloxacin; tm, trimethoprim; su, sulfamethoxazole; c, chloramphenicol; s, streptomycin; g, gentamicin; t, tetracycline; na, nalidixic acid; fl, florfenicol), and the presence of resistance ...201324135677
comparison of different preenrichment broths, egg:preenrichment broth ratios, and surface disinfection for the detection of salmonella enterica ssp. enterica serovar enteritidis in shell eggs.salmonella enterica ssp. enterica serovar enteritidis is the leading reported cause of salmonella infections. most salmonella enteritidis infections are associated with whole shell eggs and egg products. this project attempted to lay the foundation for improving the food and drug administration's current bacteriological analytical manual method for the detection of salmonella enteritidis in shell eggs. two salmonella enteritidis isolates were used for comparisons among different preenrichment an ...201324135606
mait cells detect and efficiently lyse bacterially-infected epithelial cells.mucosal associated invariant t cells (mait) are innate t lymphocytes that detect a large variety of bacteria and yeasts. this recognition depends on the detection of microbial compounds presented by the evolutionarily conserved major-histocompatibility-complex (mhc) class i molecule, mr1. here we show that mait cells display cytotoxic activity towards mr1 overexpressing non-hematopoietic cells cocultured with bacteria. the nk receptor, cd161, highly expressed by mait cells, modulated the cytokin ...201324130485
identification of virulence properties in salmonella typhimurium dt104 using caenorhabditis elegans.salmonella enterica serover typhimurium definitive phage type dt104, resistant to multiple antibiotics, is one of the most widespread salmonella species in human infection worldwide. although several cohort studies indicate that dt104 carrying the multidrug resistance (mdr) locus on salmonella genomic island 1 is a possible hyper-virulent strain compared to dt104 strains without mdr, or other salmonella enterica serotypes, existing experimental evidence regarding virulence properties associated ...201324124587
role of salmonella enterica exposure in chilean crohn's disease patients.to study the association between exposure to salmonella enterica (se) and crohn's disease (cd) and its clinical implications in chilean patients.201324124330
biofilm formation of salmonella serotypes in simulated meat processing environments and its relationship to cell characteristics.salmonella attached to meat contact surfaces encountered in meat processing facilities may serve as a source of cross-contamination. in this study, the influence of serotypes and media on biofilm formation of salmonella was investigated in a simulated meat processing environment, and the relationships between biofilm formation and cell characteristics were also determined. all six serotypes (salmonella enterica serotype heidelberg, salmonella derby, salmonella agona, salmonella indiana, salmonel ...201324112581
evaluation of levulinic acid and sodium dodecyl sulfate as a sanitizer for use in processing georgia-grown cantaloupes.freshly harvested georgia-grown cantaloupes (cucumis melo l. var. reticulatus cv. athena and atlantis) were spot inoculated with 100 μl of a five-strain mixture of salmonella enterica serovar poona (9 log cfu/ml) at the stem scar and on the netted rind and then subjected to no treatment (control) or a 6-min treatment (tank only) in water, 120 ppm of chlorine (ph 7.0), 1% levulinic acid plus 0.1% sodium dodecyl sulfate (sds; ph 3.0), or 2% levulinic acid plus 0.2% sds (ph 3.0). the log reduction ...201324112578
campylobacter spp., yersinia enterocolitica, and salmonella enterica and their simultaneous occurrence in german fattening pig herds and their environment.campylobacter spp., salmonella enterica, and yersinia enterocolitica are common causes of foodborne infections in humans with pork as a potential source. monitoring programs at farm level are, to date, only implemented for s. enterica, while epidemiological knowledge of the other two pathogens is still lacking. this study aimed to assess the pathogen load (in the pigs' environment) in fattening pig herds, their simultaneous occurrence, and the occurrence of campylobacter spp. and y. enterocoliti ...201324112569
identification of diverse salmonella serotypes, virulotypes, and antimicrobial resistance phenotypes in waterfowl from chile.salmonella enterica is a pathogen with a wide host-range that presents great concern in developed and developing countries. to determine and characterize salmonella strains found in chile's waterfowl, we sampled 758 birds along 2000 km of the chilean coast. in this sample, 46 isolates from 10 serotypes were detected, several with multidrug resistance phenotypes and different combinations of virulence-associated genes (virulotypes). these results suggest that salmonella infection in waterfowl in ...201324107205
distribution of serotypes and genotypes of salmonella enterica species in french pig production.the population of salmonella found at various stages of pig production in france was characterised to analyse the distribution and spread of salmonella in the pig production chain. we serotyped and genotyped by pfge 174 isolates collected from breeding pigs from breeding farms, 163 collected from breeding pigs from production farms, and 325 collected from fattening pigs. forty-seven serovars and 110 genotypes were identified. the major serovars were s derby (263 isolates) and s typhimurium (162 ...201324106251
characterization of drug resistance and virulotypes of salmonella strains isolated from food and humans.the virulence of bacteria can be evaluated through both phenotypic and molecular assays. we applied these techniques to 114 strains of salmonella enterica subsp. enterica collected from july 2010 to june 2012. salmonella strains were of human origin (71/114) or isolated from food (43/114). the strain set included only the three predominant salmonella serovars isolated in italy from humans (s. enteritidis, s. typhimurium, s. 4,[5],12:i:-). these strains were screened via polymerase chain reaction ...201324102078
increase in salmonella enterica serovar paratyphi a infections in phnom penh, cambodia, january 2011 to august 2013.we report an increased number of salmonella enterica paratyphi a infections in adults in cambodia. between january 2011 and august 2013, 71 s. paratyphi a isolates were recovered from blood cultures, representing a 44-fold increase compared to july 2007 to december 2010, while monthly numbers of cultures did not change. infections with s. typhi increased two-fold in the same period. most cases came from the capital phnom penh. these findings warrant epidemiological investigation to support publi ...201324094060
draft genome sequences of two salmonella strains from the sara collection, sara64 (muenchen) and sara33 (heidelberg), provide insight into their antibiotic resistance.the salmonella enterica strains that are representatives of the s. enterica serovar typhimurium complex in reference collection a (sara) are closely related but exhibit differences in antibiotic resistance, which could have public health consequences. to better understand the mechanisms behind these resistances, we sequenced the genomes of two multidrug-resistant strains: sara64 (muenchen) and sara33 (heidelberg).201324092796
unusual manifestation of salmonella enterica serotype enteritidis infection in a case of langerhans cell histiocytosis.nontyphoidal salmonella (nts) are established foodborne pathogens, most commonly reported in cases of gastroenteritis. these pathogens are however, increasingly being implicated in cases of bacteraemia and other extraintestinal manifestations. we report a case of a scalp abscess due to salmonella enterica serotype enteritidis, which is a serotype of nts, in a child suffering from a haematologic malignancy. the child was on steroid and anticancer chemotherapy and developed the abscess secondary t ...201324064654
study of the role of efflux pump in ciprofloxacin resistance in salmonella enterica serotype typhi.there are increasing reports on failure of clinical response to ciprofloxacin in typhoid fever despite the strain being sensitive to drug in in-vitro using standard guidelines and showing mutations in dna gyrase. but this increased mic and clinical failures with ciprofloxacin are not always co-related with mutations presently identified in gyra and parc genes. this shows that there may be other mechanisms such as an active drug efflux pump responsible as has been shown in other enterobacteriacea ...201324064645
salmonella enterica prevalence in leatherback sea turtles (dermochelys coriacea) in st. kitts, west indies.salmonella spp. are gram-negative bacteria capable of causing diseases in a wide range of aquatic and terrestrial animals, including humans. sea and terrestrial turtles have been recognized as carriers of this zoonotic pathogen. in this project, conventional and molecular diagnostic methods were combined to investigate the prevalence of salmonella enterica in leatherback sea turtles (dermochelys coriacea) that used the island of st. kitts, west indies as a nesting ground during 2011 (n = 21). is ...201324063110
increasing rates of salmonella paratyphi a and the current status of its vaccine development.enteric fever caused by salmonella enterica serovar typhi and salmonella enterica serovar paratyphi is still a major disease burden mainly in developing countries. previously, s. typhi was believed to be the major cause of enteric fever. the real situation is now becoming clear with reports emerging from many asian countries of s. paratyphi, mostly s. paratyphi a, causing a substantial number of cases of enteric fever. although there have been advances in the use of the currently available typho ...201324053396
trends in the antibiotic resistance patterns of enteric fever isolates - a three year report from a tertiary care centre.the incidence of multidrug resistant enteric fever is increasing alarmingly. this study was planned to determine the rate of isolation of salmonella spp. and to compare the isolates for their epidemiological parameters and antimicrobial susceptibility patterns at our center.201324043999
the plague of athens: an ancient act of bioterrorism?recent data implicate salmonella enterica serovar typhi as a causative pathogen of the plague of athens during the peloponnesian war (430-426 bc). according to thucydides, the sudden outbreak of the disease may link to poisoning of the water reservoirs by the spartans. the siege of a city was aimed at exhausting the supplies of a population, which often led to the outbreak and spread of epidemics. poisoning of the water reservoirs of a besieged city as an act of bioterrorism would probably short ...201324041196
commensal akkermansia muciniphila exacerbates gut inflammation in salmonella typhimurium-infected gnotobiotic mice.excessive mucin degradation by intestinal bacteria may contribute to inflammatory bowel diseases because access of luminal antigens to the intestinal immune system is facilitated. this study investigated how the presence of a mucin degrading commensal bacterium affects the severity of an intestinal salmonella enterica typhimurium-induced gut inflammation. using a gnotobiotic c3h mouse model with a background microbiota of eight bacterial species (sihumi) the impact of the mucin-degrading commens ...201324040367
stochastic simulation of endemic salmonella enterica serovar typhi: the importance of long lasting immunity and the carrier state.typhoid fever caused by salmonella enterica serovar typhi (s. typhi) remains a serious burden of disease, especially in developing countries of asia and africa. it is estimated that it causes 200,000 deaths per year, mainly in children. s. typhi is an obligate pathogen of humans and although it has a relatively complex life cycle with a long lived carrier state, the absence of non-human hosts suggests that well targeted control methods should have a major impact on disease. newer control methods ...201324040177
the genomic blueprint of salmonella enterica subspecies enterica serovar typhi p-stx-12.salmonella enterica subspecies enterica serovar typhi is a rod-shaped, gram-negative, facultatively anaerobic bacterium. it belongs to the family enterobacteriaceae in the class gammaproteobacteria, and has the capability of residing in the human gallbladder by forming a biofilm and hence causing the person to become a typhoid carrier. here we present the complete genome of salmonella enterica subspecies enterica serotype typhi strain p-stx-12, which was isolated from a chronic carrier in varana ...201324019994
the wbak acetyltransferase of salmonella enterica group e gives insights into o antigen evolution.o antigens are polysaccharides consisting of repeat units of three to eight sugars, generally assembled by genes in a discrete o antigen gene cluster. salmonella enterica produces 46 forms of o antigen, and most of the variation is determined by genes in the gene cluster. however in some cases the structures are modified by enzymes encoded outside of the gene cluster, and several such modifications have been reported for salmonella enterica group e, some with the genes on bacteriophages and one ...201324014662
foodborne illness outbreaks from microbial contaminants in spices, 1973-2010.this review identified fourteen reported illness outbreaks attributed to consumption of pathogen-contaminated spice during the period 1973-2010. countries reporting outbreaks included canada, denmark, england and wales, france, germany, new zealand, norway, serbia, and the united states. together, these outbreaks resulted in 1946 reported human illnesses, 128 hospitalizations and two deaths. infants/children were the primary population segments impacted by 36% (5/14) of spice-attributed outbreak ...201324010629
atlas salmonella detection method using transcription mediated amplification (tma) to detect salmonella enterica in a variety of foods and select surfaces.the atlas salmonella detection assay was compared to the reference culture methods for 12 foods and three surfaces. comparison of the atlas method to the u.s. food and drug administration bacteriological analytical manual (fda/bam) and u.s. department of agriculture-food safety and inspection service/microbiology laboratory guidebook (usda-fsis/mlg) reference methods required an unpaired approach. each method had a total of 320 samples inoculated with an s. enterica strain. each food and surface ...201324000758
non-contiguous finished genome sequence and description of salmonella enterica subsp. houtenae str. rks3027.salmonella enterica subsp. houtenae serovar 16:z4, z32:-- str. rks3027 was isolated from a human in illinois, usa. s. enterica subsp. houtenae is a facultative aerobic rod-shaped gram-negative bacterium. here we describe the features of this organism, together with the draft genome sequence and annotation. the 4,404,136 bp long genome (97 contigs) contains 4,335 protein-coding gene and 28 rna genes.201323991252
trends of etiology and drug resistance in enteric fever in the last two decades in nepal: a systematic review and meta-analysis.prospective time-trend analyses on shifting etiology and trends of drug resistance in enteric fever are scarce. using published and unpublished datasets from nepal, we performed a systematic review and meta-analysis to understand the trends in etiology and resistance to antimicrobials that have occurred since 1993. thirty-two studies involving 21 067 salmonella enterica serotype typhi (st) and s. enterica serotype paratyphi a (spa) isolates were included. there was an increasing trend in enteric ...201323985342
salmonella on feces, hides and carcasses in beef slaughter facilities in venezuela.this study determined salmonella prevalence at different stages during the slaughtering in three beef slaughter plants (a, b and c) located in the western region of venezuela (zulia and lara states). each facility was visited three times at monthly intervals, from the months october through december of 2006. samples were collected from hides (n=80), fecal grabs (n=80) and carcasses (n=80) at the phases of pre-evisceration, after-evisceration and pre-cooler at three sampling sites on the animals ...201323973832
[salmonella serovars isolated in turkey up to the end of year 2011].bacteria in salmonella genus are separated into more than 2600 serovars. it is important that the isolated serovars and their sources are known in a certain country. this will help the identification of new salmonella serovars that will be isolated later on. since there is no salmonella reference center in turkey, salmonella serovars isolated in turkey were mainly reported by the articles of aksoycan's manuscripts in various years, and in the list of töreci and anğ in 1991. the aim of this meta- ...201323971922
genome sequence of salmonella enterica serovar typhi oral vaccine strain ty21a.attenuated salmonella enterica serovar typhi strain ty21a is an important vaccine for controlling typhoid fever and serves as an oral vector for delivering heterologous antigens. the key attenuating features of this randomly mutated strain remain in question. genome sequencing has revealed 679 single nucleotide polymorphisms (snps), and will help define alterations contributing to ty21a safety and immunogenicity.201323969054
gastroenteritis outbreak associated with unpasteurized tempeh, north carolina, usa.during an investigation of an outbreak of gastroenteritis caused by salmonella enterica serovar paratyphi b variant l(+) tartrate(+), we identified unpasteurized tempeh as a novel food vehicle and rhizopus spp. starter culture as the source of the contamination. safe handling of uncooked, unpasteurized tempeh should be emphasized for prevention of foodborne illnesses.201323965530
[antibiotic resistance in nontyphoidal salmonellae serovars in the czech republic].to determine antibiotic resistance and incidence of multidrug resistance among nontyphoidal salmonellae serovars isolated from humans.201323964964
genetic lineages of salmonella enterica serovar kentucky spreading in pet reptiles.the purpose of the study was to define genetic diversity of reptilian salmonella enterica serovar (s.) kentucky isolates and their epidemiological relations to the ones from poultry, food, and environmental origin in poland. between 2010 and 2012 twenty-four s. kentucky isolates derived from snakes (n=8), geckos (n=7), chameleons (n=4), agamas (n=1), lizard (n=1), and environmental swabs taken from reptile exhibition (n=3) were identified. they were characterized with antimicrobial minimal inhib ...201323962467
free-living turtles are a reservoir for salmonella but not for campylobacter.different studies have reported the prevalence of salmonella in turtles and its role in reptile-associated salmonellosis in humans, but there is a lack of scientific literature related with the epidemiology of campylobacter in turtles. the aim of this study was to evaluate the prevalence of campylobacter and salmonella in free-living native (emys orbicularis, n=83) and exotic (trachemysscripta elegans, n=117) turtles from 11 natural ponds in eastern spain. in addition, different types of samples ...201323951312
draft genome sequence of salmonella enterica subsp. enterica serovar manhattan strain 111113, from an outbreak of human infections in northern italy.we announce the draft genome sequence of salmonella enterica subsp. enterica serovar manhattan strain 111113, isolated from a patient during an outbreak in northern italy. the genome, which was obtained with illumina miseq technology, is composed of 21 contigs for a total of 4,684,342 bp, with a g+c content of 52.17%.201323950133
genetic diversity and antimicrobial resistance profiles of salmonella enterica serotype derby isolated from pigs, pork, and humans in france.in france, salmonella enterica serotypes typhimurium and derby are the most often isolated serotypes in pigs. moreover, serotype derby usually ranks between third and fourth in prevalence among human isolates in france. the aim of this study was to evaluate the genetic relationships between human and pig salmonella derby isolates based on their pulsed-field gel electrophoresis (pfge) patterns after xbai, blni, and spei restriction and on their antimicrobial resistance profiles. the 196 studied i ...201323944749
physical interactions of fish protamine and antisepsis peptide drugs with bacterial membranes revealed by combination of specular x-ray reflectivity and grazing-incidence x-ray fluorescence.as a defined model of outer membranes of gram negative bacteria, we investigated the interaction of monolayers of lipopolysacchrides from salmonella enterica rough strains r90 (lps ra) with natural and synthetic peptides. the fine structures perpendicular to the membrane plane and the ion distribution near the interface were determined by specular x-ray reflectivity (xrr) and grazing-incidence x-ray fluorescence (gixf) in the presence and absence of divalent cations. the unique combination of xr ...201323944490
evaluation of nanoparticles as endocytic tracers in cellular microbiology.the study of pathogen interactions with eukaryotic host cells requires the introduction of fluorescent probes to visualize processes such as endocytosis, intracellular transport or host cell manipulation by the pathogen. here, three types of fluorescent nanoparticles (nps), i.e. rhodamine-labeled polymethacrylate (pma) nps, silica nps and gold nps, were employed to label the host cellular endolysosomal system and monitor manipulations by the pathogen salmonella enterica. using live cell imaging, ...201323942623
detection of biological contaminants on foods and food surfaces using laser-induced breakdown spectroscopy (libs).the rapid detection of biological contaminants, such as escherichia coli o157:h7 and salmonella enterica , on foods and food-processing surfaces is important to ensure food safety and streamline the food-monitoring process. laser-induced breakdown spectroscopy (libs) is an ideal candidate technology for this application because sample preparation is minimal and results are available rapidly (seconds to minutes). here, multivariate regression analysis of libs data is used to differentiate the liv ...201323941554
baseline antibody titres against salmonella typhi in apparently asymptomatic hiv positive individuals in a tertiary care hospital.enteric fever is common in tropical regions and is caused by salmonella enterica serotype typhi (s typhi ). for diagnosis of enteric fever, the widal test is the most widely used test after blood culture. in hiv infected individuals false positive and false negative widal reactions are common. the result is variable titres and baseline titres that are unusual in this patient population.201323940495
identification of immunogenic salmonella enterica serotype typhi antigens expressed in chronic biliary carriers of s. typhi in kathmandu, nepal.salmonella enterica serotype typhi can colonize and persist in the biliary tract of infected individuals, resulting in a state of asymptomatic chronic carriage. chronic carriers may act as persistent reservoirs of infection within a community and may introduce infection to susceptible individuals and new communities. little is known about the interaction between the host and pathogen in the biliary tract of chronic carriers, and there is currently no reliable diagnostic assay to identify asympto ...201323936575
fecal shedding of zoonotic food-borne pathogens by wild rodents in a major agricultural region of the central california coast.recent outbreaks of food-borne illness associated with the consumption of produce have increased concern over wildlife reservoirs of food-borne pathogens. wild rodents are ubiquitous, and those living close to agricultural farms may pose a food safety risk should they shed zoonotic microorganisms in their feces near or on agricultural commodities. fecal samples from wild rodents trapped on 13 agricultural farms (9 produce, 3 cow-calf operations, and 1 beef cattle feedlot) in monterey and san ben ...201323934490
working group on quality, safety and efficacy of typhoid vi capsular polysaccharide conjugate, vaccines, jeju, republic of korea, 5-7 september 2012.typhoid fever is a gastrointestinal disease transmitted through the ingestion of contaminated water or food. the bacterium, salmonella enterica subspecies enterica serovar typhi is an important cause of illness and death in many poor countries where access to safe water and basic sanitation is limited. humans are the only natural host and reservoir of s. typhi. typhoid fever causes around 21 million cases and at least 200,000 deaths per year. currently, several groups are developing typhoid conj ...201323933367
genetic boundaries to delineate the typhoid agent and other salmonella serotypes into distinct natural lineages.the deadly human typhoid agent was initially classified as a species called salmonella typhi but later reclassified as a serovar of salmonella enterica together with other pathogenically diverse serovars. the dynamic changes of salmonella taxonomy reflect the need to clarify the phylogenetic status of the salmonella serovars: are they discrete lineages or variants of a genetic lineage? to answer this question, we compared s. typhi and other salmonella serotypes. we found that the s. typhi and sa ...201323933189
detection of extended-spectrum β-lactamases and ampc β-lactamases in salmonella enterica isolates from patients in denmark during 2008-2010. 201323932741
gene expression analysis of salmonella enterica spi in macrophages indicates differences between serovars that induce systemic disease from those normally causing enteritis.global gene expression of the invasive salmonella serovars s. enteritidis and s. typhimurium, and the less-invasive s. infantis and s. hadar was studied during infection of a chicken macrophage cell line. major functional gene groups responsible for intracellular physiological changes were regulated similarly in all four serovars. however, spi1 and spi4 genes of s. enteritidis and s. typhimurium were strongly repressed in the macrophages whereas s. infantis, s. hadar and other similar serovars m ...201324080352
lymph node colonization dynamics after oral salmonella typhimurium infection in mice.an understanding of how pathogens colonize their hosts is crucial for the rational design of vaccines or therapy. while the molecular factors facilitating the invasion and systemic infection by pathogens are a central focus of research in microbiology, the population biological aspects of colonization are still poorly understood. here, we investigated the early colonization dynamics of salmonella enterica subspecies 1 serovar typhimurium (s. tm) in the streptomycin mouse model for diarrhea. we f ...201324068916
salmonella gallinarum field isolates from laying hens are related to the vaccine strain sg9r.salmonella enterica subspecies enterica serotype gallinarum can cause severe systemic disease in chickens and a live salmonella gallinarum 9r vaccine (sg9r) has been used widely to control disease. using whole-genome sequencing we found point mutations in the pyruvate dehydrogenase (acee) and/or lipopolysaccharide 1,2-glucosyltransferase (rfaj) genes that likely explain the attenuation of the sg9r vaccine strain. molecular typing using pulsed field gel electrophoresis and multiple-locus variable ...201323994381
a novel method for purification of vi capsular polysaccharide produced by salmonella enterica subspecies enterica serovar typhi.vi capsular polysaccharide is the major component of vi polysaccharide typhoid vaccines. vi is synthesized during growth of salmonella enterica subspecies enterica serovar typhi and is released into the fermentation broth in large quantities. along with the vi considerable amounts of impurities consisting of bacterial protein, nucleic acid and lipopolysaccharide (lps) as well as media components contaminate the fermentation broth. a purification method based on selective precipitation of vi usin ...201323994374
infection of chickens with antimicrobial-resistant salmonella enterica typhimurium dt193 and monophasic salmonella typhimurium-like variants: an emerging risk to the poultry industry?antimicrobial-resistant salmonella enterica poses a particular risk to public health, and in particular isolates belonging to clonal lineages such as salmonella typhimurium dt104 cause epidemics across species including poultry. in recent years, antimicrobial-resistant s. typhimurium dt193 and specifically the monophasic s. typhimurium-like variants of this phage type, serotypes 4,12:i:- and 4,5,12:i:-, have become an increasing risk to public health in europe and the usa and now account for nea ...201323930753
neck abscess caused by salmonella enterica serotype enteritidis. 201323927985
resistance genes, phage types and pulsed field gel electrophoresis pulsotypes in salmonella enterica strains from laying hen farms in southern italy.twenty-four salmonella enterica isolates (13 serovar enteritidis and 11 typhimurium) isolated from 5,600 samples from intensive laying hen farms in italy in 1998-2007 were characterized for antimicrobial resistance genes, pulsotype and phage type. most of s. typhimurium strains were pulsotype stymxb.0147 (81.8%), phage type dt143 and resistant to sulfamethoxazole encoded by sul2. two multidrug resistant (mdr) strains were identified. one strain, stymxb.0061, was resistant to ampicillin (a), chlo ...201323924880
a phase i, dose-escalation trial in adults of three recombinant attenuated salmonella typhi vaccine vectors producing streptococcus pneumoniae surface protein antigen pspa.live, attenuated, orally-administered salmonella strains are excellent vectors for vaccine antigens and are attractive as vaccines based on previous use of s. typhimurium in animals. a phase i dose escalation trial was conducted to evaluate the safety and immunogenicity of three newly constructed recombinant attenuated salmonella enterica serovar typhi vaccine (rasv) vectors synthesizing streptococcus pneumoniae surface protein a (pspa).201323916987
rapid, sensitive recovery of recombinant attenuated salmonella enterica serovar typhi vaccine strains from human blood.prior to initiating a phase 1 dose escalation trial of the safety and immunogenicity of live, oral, recombinant, attenuated salmonella enterica serovar typhi vaccine strains in human subjects, the suitability of conventional blood culture procedures to rapidly and reliably detect the organisms in human blood was investigated. blood culture specimens, with and without added growth supplements, were inoculated with study organism concentrations ranging from approximately 300 to as few as 1 to 2 cf ...201323885029
prevalence of salmonella in wild snakes in japan.a total of 87 wild snakes of 6 species in 2 families collected in japan were examined for the presence of salmonella. the prevalence of salmonella was 58.6%, and that of salmonella enterica subspecies i, which includes most human pathogenic serotypes, accounted for 12.6%. s. enterica subspecies i was isolated from japanese grass snakes and japanese four-striped snakes, and the isolates belonged to 6 serotypes: s. enterica subspecies enterica serotypes eastbourne, mikawashima, narashino, newport, ...201323883839
outbreak-associated salmonella enterica serotypes and food commodities, united states, 1998-2008.salmonella enterica infections are transmitted not only by animal-derived foods but also by vegetables, fruits, and other plant products. to clarify links between salmonella serotypes and specific foods, we examined the diversity and predominance of food commodities implicated in outbreaks of salmonellosis during 1998-2008. more than 80% of outbreaks caused by serotypes enteritidis, heidelberg, and hadar were attributed to eggs or poultry, whereas >50% of outbreaks caused by serotypes javiana, l ...201323876503
rflm functions as a transcriptional repressor in the autogenous control of the salmonella flagellar master operon flhdc.motility of bacteria like salmonella enterica is a highly regulated process that responds to a variety of internal and external stimuli. a hierarchy of three promoter classes characterizes the salmonella flagellar system, and the onset of flagellar gene expression depends on the oligomeric regulatory complex and class 1 gene product flhd(4)c(2). the flhdc promoter is a target for a broad range of transcriptional regulators that bind within the flhdc promoter region and either negatively or posit ...201323873910
use of allyl isothiocyanate and carbon nanotubes in an antimicrobial film to package shredded, cooked chicken meat.we developed antimicrobial packaging incorporated with allyl isothiocyanate (ait) and carbon nanotube (cnt), and this packaging was used for shredded cooked chicken meat inoculated with salmonella choleraesuis. the following parameters were analysed during the 40 days of storage: microbial counts, colour characteristics and changes in the oxidation of the meat as well as changes in the mechanical properties of the film, the structure of the antimicrobial film and the diffusion of the antimicrobi ...201323871073
distribution of salmonella enterica isolates from human cases in italy, 1980 to 2011. 201323870078
salmonella enterica delivers its genotoxin through outer membrane vesicles secreted from infected cells.cytolethal-distending toxins (cdts) belong to a family of dna damage inducing exotoxins that are produced by several gram-negative bacteria. salmonella enterica serovar typhi expresses its cdt (named as typhoid toxin) only in the salmonella-containing vacuole (scv) of infected cells, which requires its export for cell intoxication. the mechanisms of secretion, release in the extracellular space and uptake by bystander cells are poorly understood. we have addressed these issues using a recombinan ...201323869968
performance of stool cultures before and after a 3-day hospitalization: fewer cultures, better for patients and for money.we evaluated retrospectively the yield of stool culture (sc) depending on the length of hospitalization, and we characterized the patients missed by the 3-day rejection rule. sc detects bacterial enteric pathogens (campylobacter spp., salmonella enterica, yersinia spp., shigella spp.). during this 5-year study period, 13,039 scs were requested, and 376 were positive (2.9%). the yield of sc dropped from 11.7% before 3 days of hospitalization to 0.7% after 3 days in children and 4.3% to 0.3% in ad ...201323867328
[metabolism of salmonella enterica serovar typhi influenced by rpoe and rpos under hyperosmosis].to study the role of rpoe and rpos on the influence of the metabolism and growth of bacterial under hyperosmotic stress.201323866755
salmonella enterica serovar typhi cutf is upregulated during environmental stress. 201323863294
loss of very-long o-antigen chains optimizes capsule-mediated immune evasion by salmonella enterica serovar typhi.expression of capsular polysaccharides is a variable trait often associated with more-virulent forms of a bacterial species. for example, typhoid fever is caused by the capsulated salmonella enterica serovar typhi, while nontyphoidal salmonella serovars associated with gastroenteritis are noncapsulated. here we show that optimization of the immune evasive properties conferred by the virulence-associated (vi) capsular polysaccharide involved an additional alteration to the cell envelope of s. typ ...201323860765
evaluation of an electricity-free, culture-based approach for detecting typhoidal salmonella bacteremia during enteric fever in a high burden, resource-limited setting.in many rural areas at risk for enteric fever, there are few data on salmonella enterica serotypes typhi (s. typhi) and paratyphi (s. paratyphi) incidence, due to limited laboratory capacity for microbiologic culture. here, we describe an approach that permits recovery of the causative agents of enteric fever in such settings. this approach involves the use of an electricity-free incubator based upon use of phase-change materials. we compared this against conventional blood culture for detection ...201323853696
salmonella typhi rib osteomyelitis with abscess mimicking a 'cold abscess'.salmonella enterica serovar typhi (salmonella typhi) causing typhoid fever is common in many parts of the world particularly in developing countries. extra-intestinal manifestations such as osteomyelitis are rare in immunocompetent individuals. we report a case of salmonella typhi osteomyelitis of a rib with overlying abscess mimicking a 'cold abscess', treatment outcomes and discuss relevant literature.201323853436
outbreak of salmonella heidelberg infections linked to a single poultry producer -- 13 states, 2012-2013.in june 2012, the oregon health authority and the washington state department of health noted an increase in the number of salmonella enterica serotype heidelberg clinical isolates sharing an identical pulsed-field gel electrophoresis (pfge) pattern. in 2004, this pattern had been linked to chicken from foster farms by the washington state department of health; preliminary 2012 interviews with infected persons also indicated exposure to foster farms chicken. on august 2, 2012, cdc's pulsenet* de ...201323842445
prevalence, serovars, and antimicrobial susceptibility of salmonella isolated from blue land crabs (cardisoma guanhumi) in grenada, west indies.samples of intestine and hepatopancreas from 65 blue land crabs (cardisoma guanhumi), a crustacean commonly consumed as a food item in grenada, were collected from six geographic sites in grenada and tested for salmonella by enrichment and selective culture. the individual animal prevalence of salmonella based on isolation was 17% (11 of 65), and all infected crabs were from three of the six sampled locations. isolates were identified by serotyping as salmonella enterica serovars saintpaul (n = ...201323834805
protective immunity to salmonella enterica is partially serogroup specific.pre-harvest reduction of salmonella carriage by swine would benefit both animal health and food quality. while vaccination is an attractive pre-harvest intervention to reduce salmonella levels in swine, the large number of potential salmonella enterica serovars found in swine makes it critical that vaccines provide broad serotype efficacy. in order to directly compare the relative efficacy of salmonella vaccines against serogroup-matched and serogroup-unmatched salmonella, we vaccinated pigs wit ...201323830894
identification of salmonella enterica serovar typhi genotypes by use of rapid multiplex ligation-dependent probe amplification.salmonella enterica serovar typhi, the causative agent of typhoid fever, is highly clonal and genetically conserved, making isolate subtyping difficult. we describe a standardized multiplex ligation-dependent probe amplification (mlpa) genotyping scheme targeting 11 key phylogenetic markers of the s. typhi genome. the mlpa method demonstrated 90% concordance with single nucleotide polymorphism (snp) typing, the gold standard for s. typhi genotyping, and had the ability to identify isolates of th ...201323824765
rbrothers: r package for bayesian multiple change-point recombination detection.phylogenetic recombination detection is a fundamental task in bioinformatics and evolutionary biology. most of the computational tools developed to attack this important problem are not integrated into the growing suite of r packages for statistical analysis of molecular sequences. here, we present an r package, rbrothers, that makes a bayesian multiple change-point model, one of the most sophisticated model-based phylogenetic recombination tools, available to r users. moreover, we equip the bay ...201323818749
ndm-1 carbapenemase-producing salmonella enterica subsp. enterica serovar corvallis isolated from a wild bird in germany. 201323818284
[isolation of salmonella enterica serovar typhi in a mesenteric adenopathy]. 201323817655
decreased coenzyme a levels in rida mutant strains of salmonella enterica result from inactivated serine hydroxymethyltransferase.the rida/yer057/uk114 family of proteins is well represented across the domains of life and recent work has defined both an in vitro activity and an in vivo role for rida. rida proteins have enamine deaminase activity, and in their absence the reactive 2-aminoacrylate (2-aa) accumulates and inactivates at least some pyridoxal 5'-phosphate (plp)-containing enzymes in salmonella enterica. the conservation of rida suggested that 2-aa was a ubiquitous cellular stressor that was generated in central ...201323815688
antimicrobial resistance of salmonella enterica serovar heidelberg isolated from poultry in alberta.salmonella enterica serovar heidelberg is one of the top three serovars implicated in human infections in canada. in 2003, the canadian integrated program for antimicrobial resistance surveillance reported antimicrobial resistance (amr) in s. heidelberg in canada. the study objective was to investigate the amr of s. heidelberg isolated from poultry in alberta. we examined 951 s. heidelberg poultry isolates obtained during 1996 to 2010 and tested against 18 antibiotics using the sensititre avian1 ...201323815674
lipid-rich enteral nutrition regulates mucosal mast cell activation via the vagal anti-inflammatory reflex.nutritional stimulation of the cholecystokinin-1 receptor (cck-1r) and nicotinic acetylcholine receptor (nachr)-mediated vagal reflex was shown to reduce inflammation and preserve intestinal integrity. mast cells are important early effectors of the innate immune response; therefore modulation of mucosal mast cells is a potential therapeutic target to control the acute inflammatory response in the intestine. the present study investigates intestinal mast cell responsiveness upon nutritional acti ...201323812038
[rapid methods for the genus salmonella bacteria detection in food and raw materials].the article considers sanitary and epidemiological aspects and the impact of salmonella food poisoning in russia and abroad. the main characteristics of the agent (salmonella enterica subsp. enteritidis) are summarized. the main sources of human salmonella infection are products of poultry and livestock (poultry, eggs, dairy products, meat products, etc.). standard methods of identifying the causative agent, rapid (alternative) methods of analysis of salmonella using differential diagnostic medi ...201323808276
an antioxidant role for catecholate siderophores in salmonella.iron acquisition is an important aspect of the host-pathogen interaction. in the case of salmonella it is established that catecholate siderophores are important for full virulence. in view of their very high affinity for ferric iron, functional studies of siderophores have been almost exclusively focused on their role in acquisition of iron from the host. in the present study, we investigated whether the siderophores (enterobactin and salmochelin) produced by salmonella enterica sv. typhimurium ...201323805839
therapeutic effects of bacteriophages against salmonella gallinarum infection in chickens.in this study the isolation and characterization of three bacteriophages (st4, l13, and sg3) infecting salmonella gallinarum were carried out. they were further tested for their in vivo efficacy in phage therapy. all three phages belong to the siphoviridae family with isometric heads and non-contractile tails. they have a broad host range among serovars of salmonella enterica. the burst sizes were observed to be 1670, 80, and 28 for st4, l13, and sg3, respectively. the in vivo efficacy of the ph ...201323801253
the biology of the pmra/pmrb two-component system: the major regulator of lipopolysaccharide modifications.the ability of gram-negative bacteria to resist killing by antimicrobial agents and to avoid detection by host immune systems often entails modification to the lipopolysaccharide (lps) in their outer membrane. in this review, we examine the biology of the pmra/pmrb two-component system, the major regulator of lps modifications in the enteric pathogen salmonella enterica. we examine the signals that activate the sensor pmrb and the targets controlled by the transcriptional regulator pmra. we disc ...201323799815
immune response variations to salmonella enterica serovar typhi recombinant porin proteins in mice.typhoid fever is caused by salmonella enterica serovar typhi. ompc, ompf and ompa, the three major outer membrane proteins (omps), could serve as vaccine candidates.201323796754
substantial within-animal diversity of salmonella isolates from lymph nodes, feces, and hides of cattle at slaughter.lymph nodes (mandibular, mesenteric, mediastinal, and subiliac; n = 68) and fecal (n = 68) and hide (n = 35) samples were collected from beef carcasses harvested in an abattoir in mexico. samples were analyzed for salmonella, and presumptive colonies were subjected to latex agglutination. of the isolates recovered, a subset of 91 was characterized by serotyping, pulsed-field gel electrophoresis (pfge), and antimicrobial susceptibility phenotyping. salmonella was isolated from 100% (hide), 94.1% ...201323793628
population structure of salmonella enterica serovar 4,[5],12:b:- strains and likely sources of human infection.salmonella enterica serovar 4,[5],12:b:- is a monophasic serovar not able to express the second-phase flagellar antigen (h2 antigen). in germany, the serovar is occasionally isolated from poultry, reptiles, fish, food, and humans. in this study, a selection of 67 epidemiologically unrelated salmonella enterica serovar 4,[5],12:b:- strains isolated in germany between 2000 and 2011 from the environment, animal, food, and humans was investigated by phenotypic and genotypic methods to better underst ...201323793625
cloning, expression, and purification of the hemolysin/cytolysin (hlye antigen) from salmonella enterica serovar typhi: potential application for immunoassay development.the hemolysin (hlye) protein of salmonella enterica serovar typhi was reported to be antigenic. this work describes the cloning, expression, and purification of a hexahistidine-tagged hlye protein under native conditions. immunoblot analysis and a competitive enzyme-linked immunosorbent assay using sera from typhoid patients showed the presence of hlye-specific antibodies in circulation.201323790417
an outbreak of foodborne gastroenteritis caused by dual pathogens, salmonella enterica serovar weltevreden and vibrio fluvialis in kolkata, india.salmonella enterica serovar weltevreden and vibrio fluvialis were identified as etiological agents of a foodborne gastroenteritis outbreak after an iftar feast in north dumdum. of the 278 cases admitted to the infectious diseases hospital, kolkata, 44 stool samples were tested for the enteric pathogens. six were positive for salmonella weltevreden, 5 for vibrio fluvialis, and 8 contained both of the pathogens. consumption of mutton-ghogni might have been the likely vehicle of this outbreak. in t ...201323789767
salmonella enterica serovar minnesota urosepsis in a patient with crohn's disease in the absence of recent or current gastrointestinal symptoms.salmonella enterica serovar minnesota is a rarely isolated organism in clinical samples mainly grown from stool cultures. sepsis due to salmonella is known in severely immunocompromised patients, but so far urosepsis due to s. enterica serovar minnesota has not been described. we report a case of a 31-year-old patient suffering from crohn's disease treated with infliximab and azathioprine, in whom was implanted a double-j ureteric catheter for urolithiasis. the patient presented with urinary tra ...201323788591
phenotypic and molecular characterisation of multiresistant monophasic salmonella typhimurium (1,4,[5],12:i:-) in greece, 2006 to 2011.recently, multiresistant salmonella enterica serovar1,4,[5],12:i:-, a monophasic variant of s. typhimurium(1,4,[5],12:i:1,2) emerged, and is now among the most common serovars isolated from humans in many countries.in greece, monophasic typhimurium which was recorded for the first time in human isolates in 2007(0.3% of total isolates), increased sharply thereafter,and since 2009 is the third most frequent serovar. in the present study, 119 s. enterica 1,4,[5],12:i:- strains of human, animal and ...201323787078
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