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increased secretion of exopolysaccharide and virulence potential of a mucoid variant of salmonella enterica serovar montevideo under environmental stress.during an investigation to increase the recovery of salmonella enterica from oregano, an increased expression of exopolysaccharide was induced in salmonella serovar montevideo. the atypical mucoid (sal242s) and the non-mucoid (sal242) strains of montevideo were compared and characterized using various methods. serotyping analysis demonstrated that both strains are the same serovar montevideo. electron microscopy (em) of cultured sal242s cells revealed the production of a prominent eps-like struc ...201728012986
draft genome sequence of a multidrug-resistant cmy-2-producing salmonella enterica subsp. enterica serovar minnesota st3088 isolated from chicken meat. 201728017672
construction of a pan-genome allele database of salmonella enterica serovar enteritidis for molecular subtyping and disease cluster identification.we built a pan-genome allele database with 395 genomes of salmonella enterica serovar enteritidis and developed computer tools for analysis of whole genome sequencing (wgs) data of bacterial isolates for disease cluster identification. a web server (http://wgmlst.imst.nsysu.edu.tw) was set up with the database and the tools, allowing users to upload wgs data to generate whole genome multilocus sequence typing (wgmlst) profiles and to perform cluster analysis of wgmlst profiles. the usefulness of ...201628018331
laboratory investigation of <i>salmonella enterica</i> serovar poona outbreak in california: comparison of pulsed-field gel electrophoresis (pfge) and whole genome sequencing (wgs) results.recently, salmonella enterica serovar poona caused a multistate outbreak, with 245 out of 907 cases occurring in california. we report a comparison of pulsed-field gel electrophoresis (pfge) results with whole genome sequencing (wgs) for genotyping of salmonella poona isolates.201628018748
hysteresis in myo-inositol utilization by salmonella typhimurium.growth of salmonella enterica serovar typhimurium strain 14028 with myo-inositol (mi) as the sole carbon and energy source is characterized by a bistable phenotype that manifests in a growth phenotype with an extraordinarily long and length-variable lag phase. however, in the presence of hydrogen carbonate, in the absence of iolr that represses the mi degradation pathway, or if cells are already adapted to minimal medium (mm) with mi, the lag phase is drastically shortened, and the bistable phen ...201728027601
fowl typhoid in laying hens cause hepatic oxidative stress.the aim of this study was to analyses nitric oxide, antioxidant status, and oxidative profile in the liver of laying hens naturally infected by salmonella enterica subsp enterica serovar gallinarum (s. gallinarum). the nitrite/nitrate (nox), reactive oxygen species (ros), thiobarbituric acid-reactive substances (tbars), catalase (cat), glutathione reductase (gr), glutathione peroxidase (gpx) and glutathione s-transferase (gst) activities were measured in liver samples, as well the biomarkers of ...201728027943
nadph oxidase-1 deficiency offers little protection in salmonella typhimurium-induced typhlitis in mice.to test whether nox1 plays a role in typhlitis induced by salmonella enterica serovar typhimurium (s. tm) in a mouse model.201628028364
review on the effects of potential prebiotics on controlling intestinal enteropathogens salmonella and escherichia coli in pig production.salmonella enterica serotypes (salmonella sp.) are the second cause of bacterial foodborne zoonoses in humans after campylobacteriosis. pork is the third most important cause for outbreak-associated salmonellosis, and colibacillosis is the most important disease in piglets and swine. attachment to host cells, translocation of effector proteins into host cells, invasion and replication in tissues are the vital virulence steps of these pathogens that help them to thrive in the intestinal environme ...201628028851
identification of a stable complex between a [nife]-hydrogenase catalytic subunit and its maturation protease.salmonella enterica serovar typhimurium has the ability to use molecular hydrogen as a respiratory electron donor. this is facilitated by three [nife]-hydrogenases termed hyd-1, hyd-2, and hyd-5. hyd-1 and hyd-5 are homologous oxygen-tolerant [nife]-hydrogenases. a critical step in the biosynthesis of a [nife]-hydrogenase is the proteolytic processing of the catalytic subunit. in this work, the role of the maturation protease encoded within the hyd-5 operon, hydd, was found to be partially compl ...201728029689
outbreak of salmonella oslo infections linked to persian cucumbers - united states, 2016.in april 2016, pulsenet, the national molecular subtyping network for foodborne disease surveillance, detected a multistate cluster of salmonella enterica serotype oslo infections with an indistinguishable pulsed-field gel electrophoresis (pfge) pattern (xbai pfge pattern oslx01.0090).* this pfge pattern was new in the database; no previous infections or outbreaks have been identified. cdc, state and local health and agriculture departments and laboratories, and the food and drug administration ...201628033312
peroxiredoxin-3 is involved in bactericidal activity through the regulation of mitochondrial reactive oxygen species.peroxiredoxin-3 (prdx3) is a mitochondrial protein of the thioredoxin family of antioxidant peroxidases and is the principal peroxidase responsible for metabolizing mitochondrial hydrogen peroxide. recent reports have shown that mitochondrial reactive oxygen species (mros) contribute to macrophage-mediated bactericidal activity in response to toll-like receptors. herein, we investigated the functional effect of prdx3 in bactericidal activity. the mitochondrial localization of prdx3 in hek293t ce ...201628035213
dynamics of salmonella shedding and welfare of hens in free-range egg production systems.the current study investigated the effect of environmental stressors (i.e., weather changes) on salmonella shedding in free-range production systems and the correlations with behavioral and physiological measures (i.e., fecal glucocorticoid metabolites). this involved longitudinal and point-in-time surveys of salmonella shedding and environmental contamination on four commercial free-range layer farms. the shedding of salmonella was variable across free-range farms and in different seasons. ther ...201728039133
application of a 222-nm krypton-chlorine excilamp to control foodborne pathogens on sliced cheese surfaces and characterization of the bactericidal mechanisms.this study was conducted to investigate the basic spectral properties of a 222-nm krypton-chlorine (krcl) excilamp and its inactivation efficacy against major foodborne pathogens on solid media, as well as on sliced cheese compared to a conventional 254-nm low-pressure mercury (lp hg) lamp. selective media and sliced cheese inoculated with escherichia coli o157:h7, salmonella enterica serovar typhimurium, and listeria monocytogenes were irradiated with a krcl excilamp and a lp hg lamp at the sam ...201728039742
short communication: characterization of salmonella phages from dairy calves on farms with history of diarrhea.salmonella enterica can cause disease and mortality in calves. this pathogen is also a zoonosis that can be transmitted by animal contact or by food. the prevalence of salmonella in dairy farms has been reported to range from 0 to 64%, and, due to the diversity of salmonella serovars that can be circulating, salmonella is an important concern for dairy production. bacteriophages that infect salmonella have been documented to be abundant and widely distributed in the dairy environment. the curren ...201728041722
prevalence and antimicrobial resistance in salmonella enterica isolated from broiler chickens, pigs and meat products in thailand-cambodia border provinces.this study aimed to examine the prevalence and antimicrobial resistance (amr) of salmonella isolates from broiler chickens, pigs and their associated meat products in the thailand-cambodia border provinces. a total of 941 samples were collected from pigs and broiler chickens at slaughter houses and from carcasses at local fresh markets in sa kaeo, thailand (n = 554) and banteay meanchey, cambodia (n = 387) in 2014 and 2015. from these samples, 345 salmonella isolates were collected from sa keao ...201728042666
empirical testing of modified salmonella mlst in aquatic environmental samples by in silico analysis.multilocus sequence typing (mlst) is an approach for prediction of salmonella servoar and ebrust groups (ebgs) based on seven typing scheme of housekeeping genes. up to date, >220.000 allelic profiles and 65,973 salmonella strains have been established in the mlst database. several studies have modified mlst method with fewer targeted housekeeping genes for the purpose of economy and efficiency. nevertheless, no study has conducted systematically to evaluate the correlation between the numbers o ...201728043703
collateral damage: insights into bacterial mechanisms that predispose host cells to cancer.infections are estimated to contribute to 20% of all human tumours. viruses are known to induce cell transformation, but evidence has also linked bacteria, such as helicobacter pylori and salmonella enterica subsp. enterica serovar typhi, to different cancer types. in addition, chlamydia trachomatis, fusobacterium nucleatum and bacteroides fragilis are associated with the development of cancer, although a causal relationship has not yet been established. bacterial effectors such as colibactin an ...201728045107
spectroscopic studies of the eutt adenosyltransferase from salmonella enterica: evidence of a tetrahedrally coordinated divalent transition metal cofactor with cysteine ligation.the eutt enzyme from salmonella enterica, a member of the family of atp:cobalt(i) corrinoid adenosyltransferase (acat) enzymes, requires a divalent transition metal ion for catalysis, with fe(ii) yielding the highest activity. eutt contains a unique cysteine-rich hx11ccx2c(83) motif (where h and the last c occupy the 67th and 83rd positions, respectively, in the amino acid sequence) not found in other acats and employs an unprecedented mechanism for the formation of adenosylcobalamin. recent kin ...201728045498
rna-seq unveils new attributes of the heterogeneous salmonella-host cell communication.high-throughput rna sequencing (rna-seq) has uncovered hundreds of small rnas and complex modes of rna regulation in every bacterium analyzed to date. this complexity agrees with the adaptability of most bacteria to varied environments including, in the case of pathogens, the new niches encountered in the host. recent rna-seq studies have analyzed simultaneously gene expression in the intracellular pathogen salmonella enterica and infected host cells at population and single-cell level. distinct ...201728045572
chitosan/sulfated locust bean gum nanoparticles: in vitro and in vivo evaluation towards an application in oral immunization.this work proposes the design of nanoparticles based on locus bean gum (lbg) and chitosan to be used as oral immunoadjuvant for vaccination purposes. lbg-based nanoparticles were prepared by mild polyelectrolyte complexation between chitosan (cs) and a synthesized lbg sulfate derivative (lbgs). morphological characterization suggested that nanoparticles present a solid and compact structure with spherical-like shape. sizes around 180-200nm and a positive surface charge between +9mv and +14mv wer ...201728049014
an unusual case of septic arthritis of the hip.non-typhoidal salmonella, particularly salmonella enterica serovar typhimurium is food borne pathogen causing mild self-limiting diarrhoea in healthy adults. it can occasionally cause extraintestinal focal infection in susceptible patients. salmonella, as the aetiological agent of osteomyelitis and septic arthritis is rare and has been mostly reported in patients with sickle cell disease or thalassaemia. we report a case of septic arthritis by salmonellatyphimurium in an immunocompromised patien ...201628050370
respiration of microbiota-derived 1,2-propanediol drives salmonella expansion during colitis.intestinal inflammation caused by salmonella enterica serovar typhimurium increases the availability of electron acceptors that fuel a respiratory growth of the pathogen in the intestinal lumen. here we show that one of the carbon sources driving this respiratory expansion in the mouse model is 1,2-propanediol, a microbial fermentation product. 1,2-propanediol utilization required intestinal inflammation induced by virulence factors of the pathogen. s. typhimurium used both aerobic and anaerobic ...201728056091
erratum to: studies on the therapeutic effect of propolis along with standard antibacterial drug in salmonella enterica serovar typhimurium infected balb/c mice. 201728056925
in vivo cleavage map illuminates the central role of rnase e in coding and non-coding rna pathways.understanding rna processing and turnover requires knowledge of cleavages by major endoribonucleases within a living cell. we have employed tier-seq (transiently inactivating an endoribonuclease followed by rna-seq) to profile cleavage products of the essential endoribonuclease rnase e in salmonella enterica. a dominating cleavage signature is the location of a uridine two nucleotides downstream in a single-stranded segment, which we rationalize structurally as a key recognition determinant that ...201728061332
qseb mediates biofilm formation and invasion in salmonella enterica serovar typhi.qseb is a response regulator of the qsebc two-component system (tcs) which is associated with quorum sensing and functions as a global regulator of flagella, biofilm formation, and virulence. the function of qseb and its interaction with qsec has been the subject of study in some organisms, however, little work was done in salmonella enterica serovar typhi (s. typhi). the objective of this study was to investigate the effect of qseb on biofilm formation and virulence in s. typhi. it showed that ...201728062286
use of carvacrol, thymol, and eugenol for biofilm eradication and resistance modifying susceptibility of salmonella enterica serovar typhimurium strains to nalidixic acid.the aims of the study was to evaluate the antibacterial susceptibility and the biofilm eradication of three natural compounds carvacrol (car), thymol (th) and eugenol (eug), alone or in combination with nalidixic acid (na) against twelve salmonella typhimurium strains. the minimum inhibitory concentration (mic) and the minimum biofilm eradication concentration (bec50) of the tested compounds (car, th and eug) and their combinations with na were evaluated. in order to assess whether these bacteri ...201728062292
[bovine lactoferrin decreases the invasion of salmonella enterica to hep-2 cells].to assess the effect of bovine lactoferrin (blf) on the invasion of salmonella enterica ser. typhimurium to hep-2 cells.201728062866
ssek1 and ssek3 type iii secretion system effectors inhibit nf-κb signaling and necroptotic cell death in salmonella-infected macrophages.within host cells such as macrophages, salmonella enterica translocates virulence (effector) proteins across its vacuolar membrane via the spi-2 type iii secretion system. previously, it was shown that when expressed ectopically, the effectors ssek1 and ssek3 inhibit tumor necrosis factor alpha (tnf-α)-induced nf-κb activation. in this study, we show that ectopically expressed ssek1, ssek2, and ssek3 suppress tnf-α-induced, but not toll-like receptor 4- or interleukin-induced, nf-κb activation. ...201728069818
essential oils against pathogen and spoilage microorganisms of fruit juices: use of versatile antimicrobial delivery systems.essential oils (eo) are increasingly used as natural antimicrobial compounds, however the effect of delivery system to enhance their antimicrobial activity has not been widely studied. limonene (0 to 10 μl/ml) was added to microbial suspensions (∼10(5) cfu/ml) of selected foodborne pathogens (listeria monocytogenes scott a, salmonella enterica typhimurium, escherichia coli and staphylococcus aureus), and spoilage microorganisms (lactobacillus plantarum, saccharomyces cerevisiae, and candida albi ...201728071802
promyelocytic leukemia protein (pml) controls listeria monocytogenes infection.the promyelocytic leukemia protein (pml) is the main organizer of stress-responsive subnuclear structures called pml nuclear bodies. these structures recruit multiple interactors and modulate their abundance or their posttranslational modifications, notably by the sumo ubiquitin-like modifiers. the involvement of pml in antiviral responses is well established. in contrast, the role of pml in bacterial infection remains poorly characterized. here, we show that pml restricts infection by the patho ...201728074026
complete genome sequence of the salmonella enterica serovar enteritidis bacteriophages fse1c and fse4c isolated from food matrices.salmonella enterica serovar enteritidis is one of the most common causes of salmonellosis worldwide. utilization of bacteriophages as prophylactic agents is a practical solution to prevent salmonellosis in ready-to-eat products. shelf stability is one of the desirable properties for prophylactic bacteriophages. here, we describe the phenotype, genome, and phylogeny of fse1c and fse4s salmonella bacteriophages. fse1c and fse4s were previously isolated from pickle sauce and ground beef respectivel ...201728074119
clinical predictors of the leading pathogens in human immunodeficiency virus-infected adults with community-onset bacteremia in the emergency department: the importance of transmission routes.to investigate the clinical characteristics and pathogens of community-onset bacteremia among human immunodeficiency virus (hiv)-infected adults as well as to establish the clinical predictors of the major microorganisms.201628082067
evolution of variable number tandem repeats and its relationship with genomic diversity in salmonella typhimurium.salmonella enterica serovar typhimurium is the most common salmonella serovar causing human infections in australia and many other countries. a total of 12,112 s. typhimurium isolates from new south wales were analyzed by multi-locus variable number of tandem repeat (vntr) analysis (mlva) using five vntrs from 2007 to 2014. we found that mid ranges of repeat units of 8-14 in vntr locus sttr5, 6-13 in sttr6, and 9-12 in sttr10 were always predominant in the population (>50%). in vitro passaging e ...201628082952
in vitro development of ciprofloxacin resistance of salmonella enterica serovars typhimurium, enteritidis, and indiana isolates from food animals.difference in the development of resistance may be associated with the epidemiological spread and drug resistance of different salmonella enterica serovar strains. in the present study, three susceptible s. enterica serovars, typhimurium (st), enteritidis (se), and indiana (si) strains, were subjected to stepwise selection with increasing ciprofloxacin concentrations. the results indicated that the mutation frequencies of the si group were 10(1)-10(4) higher and developed resistance to ciproflox ...201728085562
mangrovibacter phragmitis sp. nov., an endophyte isolated from the roots of phragmites karka.a facultative anaerobic, gram-stain-negative, rod-shaped, nitrogen fixing, endophytic bacterial strain mp23t was isolated from the roots of phragmites karka growing in chilika lagoon, odisha, india. strain mp23t was slightly halophilic and optimal nacl concentration and temperature for growth was 1% and 30°c, respectively. on the basis of 16s rrna gene sequence similarities, strain mp23t was affiliated to family enterobacteriaceae and most closely related to mangrovibacter yixingensis kctc 42181 ...201728086074
cecal micrornaome response to salmonella enterica serovar enteritidis infection in white leghorn layer.salmonella enterica serovar enteritidis (se) is a food-borne pathogen and of great threat to human health through consuming the contaminated poultry products. micrornas (mirnas) play an important role in different biological activities and have been shown to regulate the innate immunity in the bacterial infection. the objective of this study is to identify mirnas associated with se infection in laying chicken cecum.201728086873
effect of in vivo neutralization of tumor necrosis alpha on the efficacy of antibiotic treatment in systemic salmonella enterica infections.immunity can co-operate with antibiotics, but can also antagonize drug efficacy by segregating the bacteria to areas of the body that are less accessible to antimicrobials, and by selecting for subpopulations with low division rates that are often difficult to eradicate. we studied the effect of an anti-inflammatory/immunosuppressive anti-tnfα treatment, which accelerates bacterial growth in the tissues and inhibits or reverses the formation of granulomas, on the efficacy of ampicillin and cipro ...201728087648
nmr line-fitting quantification of polysaccharide n-acylurea-based modification in glycoconjugates of salmonella typhi vi polysaccharide.the polysaccharides modification via carbodiimide reaction is one of the most applied methods for obtaining conjugated vaccines against salmonella enterica. however, n-acylurea carbodiimide adduct generated in the process is a critical impurity in carbohydrate-based vaccines. a quantitative nmr method was developed for assessing the n-acylurea carbodiimide adduct impurity. the procedure was based on line-fitting facilities for processing the nmr signals on complex spectra. the method showed good ...201728087987
rapid concentration detection and differentiation of bacteria in skimmed milk using surface enhanced raman scattering mapping on 4-mercaptophenylboronic acid functionalized silver dendrites.a novel method was developed to rapidly concentrate, detect, and differentiate bacteria in skimmed milk using surface enhanced raman scattering (sers) mapping on 4-mercaptophenylboronic acid (4-mpba) functionalized silver (ag) dendrites. the 4-mpba functionalized ag dendritic sers substrate was used to capture the bacterial cells and enhance the bacterial signal. salmonella, a significantly important food pathogen, was used as the representative strain to optimize and evaluate the developed meth ...201728091716
antimicrobial probiotics reduce salmonella enterica in turkey gastrointestinal tracts.despite the arsenal of technologies employed to control foodborne nontyphoidal salmonella (nts), infections have not declined in decades. poultry is the primary source of nts outbreaks, as well as the fastest growing meat sector worldwide. with recent fda rules for phasing-out antibiotics in animal production, pressure is mounting to develop new pathogen reduction strategies. we report on a technology to reduce salmonella enteritidis in poultry. we engineered probiotic e. coli nissle 1917, to ex ...201728094807
bacterium-derived cell-penetrating peptides deliver gentamicin to kill intracellular pathogens.commonly used antimicrobials show poor cellular uptake and often have limited access to intracellular targets, resulting in low antimicrobial activity against intracellular pathogens. an efficient delivery system to transport these drugs to the intracellular site of action is needed. cell-penetrating peptides (cpps) mediate the internalization of biologically active molecules into the cytoplasm. here, we characterized two cpps, α1h and α2h, derived from the yersinia enterocolitica yopm effector ...201728096156
biosynthesis, characterization, and bioactivities evaluation of silver and gold nanoparticles mediated by the roots of chinese herbal angelica pubescens maxim.a facile synthesis and biological applications of silver (dh-agnps) and gold nanoparticles (dh-aunps) mediated by the aqueous extract of angelicae pubescentis radix (du huo) are explored. du huo is a medicinal root belonging to angelica pubescens maxim which possesses anti-inflammatory, analgesic, and antioxidant properties. the absorption spectra of nanoparticles in varying root extract and metal ion concentration, ph, reaction temperatures, and time were recorded by ultraviolet-visible (uv-vis ...201728097599
mcr-1-harboring salmonella enterica serovar typhimurium sequence type 34 in pigs, china.we detected the mcr-1 gene in 21 (14.8%) salmonella isolates from pigs at slaughter; 19 were serovar typhimurium sequence type 34. the gene was located on inchi2-like plasmids that also harbored incf replicons and lacked a conjugative transfer region. these findings highlight the need to prevent further spread of colistin resistance in animals and humans.201728098547
virulent nontyphoidal salmonella producing ctx-m and cmy-2 β-lactamases from livestock, food and human infection, brazil. 201728102761
causes and outcomes of sepsis in southeast asia: a multinational multicentre cross-sectional study.improved understanding of pathogens that cause sepsis would aid management and antimicrobial selection. in this study, we aimed to identify the causative pathogens of sepsis in southeast asia.201728104185
[salmonella enterica: a review or the trilogy agent, host and environment and its importance in chile].salmonella enterica is a major foodborne pathogen worldwide, being the main cause of outbreaks by food consumption in chile. despite all efforts deployed for control and prevention, the high incidence in people still persists, with several factors that could be influencing the epidemiological behavior of this infection. the objective of this review is to identify these factors belonging to the biological agent, the human host and the environment, which probably have a greater importance in chile ...201628112339
evaluation of colonisation resistance in stool of human donors using ex vivo, in vitro and in vivo assays.the indigenous microbiota is the population of microorganisms normally present on the surface and mucosa of an individual, where it performs essential health functions, including the colonisation resistance (cr) against pathogens. to identify the bacteria responsible and the mechanisms involved in the cr, the germ-free (gf) animal model has been used, because in vitro studies cannot always be extrapolated to what occurs in vivo. in this study, ex vivo antagonism assays against seven enteropathog ...201728116929
novel temperate phages of salmonella enterica subsp. salamae and subsp. diarizonae and their activity against pathogenic s. enterica subsp. enterica isolates.forty strains of salmonella enterica (s. enterica) subspecies salamae (ii), arizonae (iiia), diarizonae (iiib), and houtenae (iv) were isolated from human or environmental samples and tested for bacteriophage production. production of bacteriophages was observed in 15 s. enterica strains (37.5%) belonging to either the subspecies salamae (8 strains) or diarizonae (7 strains). activity of phages was tested against 52 pathogenic s. enterica subsp. enterica isolates and showed that phages produced ...201728118395
candida krusei isolated from fruit juices ultrafiltration membranes promotes colonization of escherichia coli o157:h7 and salmonella enterica on stainless steel surfaces.to clarify the interactions between a common food spoilage yeast and two pathogenic bacteria involved in outbreaks associated with fruit juices, the present paper studies the effect of the interplay of candida krusei, collected from uf membranes, with escherichia coli o157:h7 and salmonella enterica in the overall process of adhesion and colonization of abiotic surfaces. two different cases were tested: a) co-adhesion by pathogenic bacteria and yeasts, and b) incorporation of bacteria to pre-adh ...201728120191
the role of universal stress proteins in bacterial infections.universal stress proteins are ubiquitously expressed in bacteria, archaea and plants and other eukaryotes. a general property of usps is their role in adaptation of bacteria to oxidative stress, high temperature, low ph and/or hypoxia. there is increasing evidence that these proteins facilitate the adaption of bacterial pathogens to the human host environment, thereby facilitating colonisation and pathogenicity. usps in mycobacterium tuberculosis are well studied and may play a role in latency o ...201728120710
identification of unannotated small genes in salmonella.increasing evidence indicates that many, if not all, small genes encoding proteins ≤100 aa are missing in annotations of bacterial genomes currently available. to uncover unannotated small genes in the model bacterium salmonella enterica typhimurium 14028s, we used the genomic technique ribosome profiling, which provides a snapshot of all mrnas being translated (translatome) in a given growth condition. for comprehensive identification of unannotated small genes, we obtained salmonella translato ...201728122954
[bacteremia caused by ciprofloxacin-resistant salmonella serotype kentucky: a case report and the review of literature].salmonella infections can be seen in four clinical types, namely gastroenteritis, bacteremia/sepsis, enteric fever and carriage. these infections can result in uncomplicated diarrhea in most cases, but can lead to invasive disease requiring antimicrobial therapy and can be life-threatening in elderly or immunocomprimised patients. broad-spectrum cephalosporins and fluoroquinolones are crucial options in the treatment of the invasive infections. ciprofloxacin resistance is rarely seen in non-typh ...201628124965
whole-genome sequence and annotation of salmonella enterica subsp. enterica serovar enteritidis phage type 8 strain en1660.the genome of salmonella enterica subspecies enterica serovar enteritidis phage type 8 strain en1660, isolated from an outbreak in thunder bay, canada, was sequenced to 46-fold coverage using an illumina miseq with 300-bp paired-end sequencing chemistry to produce 28 contigs with an n50 value of 490,721 bp.201728126943
differential attachment of salmonella enterica and enterohemorrhagic escherichia coli to alfalfa, fenugreek, lettuce, and tomato seeds.vegetable seeds have the potential to disseminate and transmit foodborne bacterial pathogens. this study was undertaken to assess the abilities of selected salmonella and enterohemorrhagic escherichia coli (ehec) strains to attach to fungicide-treated versus untreated, and intact versus mechanically damaged, seeds of alfalfa, fenugreek, lettuce, and tomato. surface-sanitized seeds (2 g) were exposed to four individual strains of salmonella or ehec at 20°c for 5 h. contaminated seeds were rinsed ...201728130295
novel aldo-keto reductases for the biocatalytic conversion of 3-hydroxybutanal to 1,3-butanediol: structural and biochemical studies.the nonnatural alcohol 1,3-butanediol (1,3-bdo) is a valuable building block for the synthesis of various polymers. one of the potential pathways for the biosynthesis of 1,3-bdo includes the biotransformation of acetaldehyde to 1,3-bdo via 3-hydroxybutanal (3-hb) using aldolases and aldo-keto reductases (akrs). this pathway requires an akr selective for 3-hb, but inactive toward acetaldehyde, so it can be used for one-pot synthesis. in this work, we screened more than 20 purified uncharacterized ...201728130301
a live attenuated mutant of salmonella montevideo triggers il-6, ifn-γ and il-12 cytokines that co-related with humoral and cellular immune responses required for reduction of challenge bacterial load in experimental chickens.a live attenuated salmonella enterica serovar montevideo (sm) mutant jol1599 was constructed by deletion of virulence-associated genes. the protective efficacy and immune response profiles of chickens immunized with jol1599 were investigated. immunized chickens demonstrated significant increases in plasma igg and lymphocyte proliferative responses (p≤0.05). increased levels of il-6, inf-γ, and il-12 were also observed. immunized birds strongly responded to infection by rapid stimulation of a cd4 ...201728131368
health survey of free-ranging raccoons (procyon lotor) in central park, new york, new york, usa: implications for human and domestic animal health.we conducted health assessments on 113 free-ranging raccoons ( procyon lotor ) in central park, new york city, us, in february 2010, september 2010, and november 2011 in conjunction with a trap-vaccinate-release program to control a raccoon rabies epizootic. five individuals were sampled at two time points for 118 raccoon examinations in total. we tested 13 of 13 and 8 of 13 euthanized raccoons for rabies and canine distemper virus (cdv), respectively, by antigen testing on brain tissue; all wer ...201728135131
a whole-genome sequencing approach to study cefoxitin-resistant salmonella enterica serovar heidelberg isolates from various sources.this study characterized cefoxitin-resistant and -susceptible salmonella enterica serovar heidelberg strains from humans, abattoir poultry, and retail poultry to assess the molecular relationships of isolates from these sources in québec in 2012. isolates were collected as part of the canadian integrated program for antimicrobial resistance surveillance (cipars). all isolates were subjected to antimicrobial susceptibility testing, pcr for cmy-2, pulsed-field gel electrophoresis (pfge), and whole ...201728137797
the mechanism of killing by the proline-rich peptide bac7(1-35) against clinical strains of pseudomonas aeruginosa differs from that against other gram-negative bacteria.pseudomonas aeruginosa infections represent a serious threat to worldwide health. proline-rich antimicrobial peptides (pr-amps), a particular group of peptide antibiotics, have demonstrated in vitro activity against p. aeruginosa strains. here we show that the mammalian pr-amp bac7(1-35) is active against some multidrug-resistant cystic fibrosis isolates of p. aeruginosa by confocal microscopy and cytometric analyses, we investigated the mechanism of killing against p. aeruginosa strain pao1 and ...201728137800
cattle-derived salmonella enterica serovar dublin infections in red foxes ( vulpes vulpes ) in tyrol, austria.salmonella enterica serovar dublin is endemic in the cattle population in some areas of the austrian province tyrol, and each year single dairy farms have experienced clinical infections. to ascertain if tyrolean red foxes ( vulpes vulpes ) act as a reservoir for salmonella spp., we tested hepatic tissue and intestinal content from foxes hunted in the years 2015-16 by using microbiological methods. in addition, we included several fox fecal samples collected on a mountain pasture near chamois ca ...201728139955
effect of chitosan physical form on its antibacterial activity against pathogenic bacteria.the antibacterial activity of chitosan (cs) nanospheres, in comparison with other physical forms, was investigated against salmonella enterica serovar typhimurium and staphylococcus aureus, which are 2 foodborne harmful pathogens. results showed that the antibacterial efficacy of cs nanospheres: (1) was superior to that displayed by cs in powder and solution form; (2) was higher against s. aureus than against salmonella typhimurium; and (3) was dependent on the temperature and ph of the medium d ...201728140469
homologous prime-boost immunization with live attenuated salmonella enterica serovar senftenberg and its preventive efficacy against experimental challenge with various strains of s. senftenberg.the heterogeneity observed regarding persistence, and subsequent fecal shedding pattern of the salmonella senftenberg (s. senftenberg) serovar in chicken's calls for development of the optimized immunization strategy which can provide protection against various s. senftenberg isolated. optimization of an immunization strategy with a live attenuated s. senftenberg (δlon and δcpxr) vaccine candidate (jol1587) was undertaken in this study to evaluate the ability of a homologous prime-boost immuniza ...201728143524
quantitative proteomics charts the landscape of salmonella carbon metabolism within host epithelial cells.we performed a proteomic survey of salmonella enterica serovar typhimurium during infection of host epithelial cells. our data reveal substantial metabolic reshuffling of salmonella in the host in addition to severe degeneration of bacterial flagella and chemotaxis systems. the large-scale quantitative data allowed us to chart an overview of intracellular salmonella carbon metabolism. notably, we found preferential utilization of glycolysis, the pentose phosphate pathway, mixed acid fermentation ...201728152601
draft genome sequence of the tumor-targeting salmonella enterica serovar typhimurium strain sl7207.salmonella enterica serovar typhimurium strain sl7207 is a genetically modified derivative of strain sl1344, which preferentially accumulates in tumors and can be used as a vehicle for tissue-specific gene delivery in vivo here, we report the draft genome sequence of sl7207, confirming a purported aroa deletion and four single-nucleotide polymorphisms compared to sl1344.201728153911
towards an understanding of salmonella enterica serovar typhimurium persistence in swine.salmonella enterica is an important food borne pathogen that is frequently carried by swine. carrier animals pose a food safety risk because they can transmit s. enterica to finished food products in the processing plant or by contamination of the environment. environmental contamination has become increasingly important as non-animal foods (plant-based) have been implicated as sources of s. enterica. the prevalence of s. enterica in swine is high and yet carrier animals remain healthy. s. enter ...201628155802
evaluation of the clinical and microbiological response to salmonella paratyphi a infection in the first paratyphoid human challenge model.to expedite the evaluation of vaccines against paratyphoid fever, we aimed to develop the first human challenge model of salmonella enterica serovar paratyphi a infection.201728158395
utilization of a molecular serotyping method for salmonella enterica in a routine laboratory in alberta canada.salmonella is one of the most common enteric pathogens related to foodborne illness. alberta's provincial laboratory for public health (provlab) provides outbreak and surveillance support by performing serotyping. the check&trace salmonella™ (cts) assay (check-points, netherlands), a commercial dna microarray system, can determine the serotype designation of a salmonella isolate with automated interpretation. here we evaluate 1028 salmonella isolates of human clinical or environmental sources in ...201728159627
epidihydropinidine, the main piperidine alkaloid compound of norway spruce (picea abies) shows promising antibacterial and anti-candida activity.this study reports for the first time promising antibacterial and antifungal effects of epidihydropinidine, the major piperidine alkaloid in the needles and bark of norway spruce, picea abies (l.) karsten. epidihydropinidine was growth inhibitory against all bacterial and fungal strains used in our investigation, showing the lowest mic value of 5.37μg/ml against pseudomonas aeruginosa, enterococcus faecalis, candida glabrata and c. albicans. epidihydropinidine was nearly three times more active ...201728163074
salmonella enterica serovar typhi lipopolysaccharide o-antigen modification impact on serum resistance and antibody recognition.salmonella enterica serovar typhi is a human-restricted gram-negative bacterial pathogen responsible for causing an estimated 27 million cases of typhoid fever annually, leading to 217,000 deaths, and current vaccines do not offer full protection. the o-antigen side chain of the lipopolysaccharide is an immunodominant antigen, can define host-pathogen interactions, and is under consideration as a vaccine target for some gram-negative species. the composition of the o-antigen can be modified by t ...201728167670
comparative analysis of the bacterial membrane disruption effect of two natural plant antimicrobial peptides.in the medicago truncatula genome about 700 genes code for nodule-specific cysteine-rich (ncr) small peptides that are expressed in the symbiotic organ, the root nodule, where they control terminal differentiation of the endosymbiotic rhizobium bacteria to nitrogen-fixing bacteroids. cationic ncr peptides were predicted to have antimicrobial activities. here antibacterial activities of ncr247, ncr335, polymyxin b (pmb), and streptomycin were investigated and compared on two foodborne pathogens s ...201728167938
identification of the crucial genes in the elimination and survival process of salmonella enterica ser. pullorum in the chicken spleen.salmonella enterica ser. pullorum is one of the most easily re-infecting pathogens in poultry production because of its mechanism of escaping from immune elimination. we used the transcriptome method to investigate the variation in gene expression in chicken spleen resulting from the interaction between hosts and s. pullorum in the survival process. the expression of various genes related to the maturation and activation of b cells was activated before s. pullorum was eliminated, which might hel ...201728176342
ceruloplasmin-derived peptide is the strongest regulator of oxidative stress and leukotriene synthesis in neutrophils.ceruloplasmin, an acute-phase protein, can affect the activity of leukocytes through its various enzymatic activities and protein-protein interactions (with lactoferrin, myeloperoxidase, eosinophil peroxidase, serprocidins, and 5-lipoxygenase (5-lox), among others). however, the molecular mechanisms of ceruloplasmin activity are not clearly understood. in this study, we tested the ability of two synthetic peptides, rpylkvfnpr (883-892) (p1) and rrpylkvfnprr (882-893) (p2), corresponding to the i ...201728177760
the mals-5'utr regulates hisg, a key gene in the histidine biosynthetic pathway in salmonella enterica serovar typhi.bacterial noncoding rnas (ncrna) regulate diverse cellular processes, including virulence and environmental fitness. the mals 5' untranslated region (named mals-5'utr) was identified as a regulatory ncrna that increases the invasive capacity of salmonella enterica serovar typhi. an intarna search suggested base pairing between mals-5'utr and hisg mrna, a key gene in the histidine biosynthetic pathway. overexpression of mals-5'utr markedly reduced bacterial growth in minimal medium without histid ...201728177798
comparison of the antimicrobial and sanitizer resistance of salmonella isolates from chicken slaughter processes in korea.salmonella is a foodborne pathogen worldwide. outbreaks of salmonella are commonly associated with consumption of contaminated foods such as poultry products. therefore, the objective of this study was to determine the occurrence, biofilm formation, antibiotic resistance, and sanitizer resistance of salmonella enterica isolated from chicken carcasses. a total of 318 samples were collected from 15 chicken slaughterhouses in 8 provinces of korea. they were then examined for salmonella contaminatio ...201728178381
self-oligomerizing structure of the flagellar cap protein flid and its implication in filament assembly.flid is a self-oligomerizing structural protein that caps the growing end of the bacterial flagellar filament. flid also plays a key role in the flagellar system by continuously adding a new flagellin protein to the tip of the filament. to structurally characterize flid oligomerization and to provide a flid-mediated flagellin polymerization mechanism, we have determined the crystal structures of flid proteins from escherichia coli and salmonella enterica serovar typhimurium (ecflid and stflid, r ...201728179186
(99m) tc-tazobactam, a novel infection imaging agent: radiosynthesis, quality control, biodistribution, and infection imaging studies.the radiolabeled drug (99m) tc-tazobactam ((99m) tc-tzb) was developed and assessed as an infection imaging agent in pseudomonas aeruginosa and salmonella enterica infection-induced animal models by comparing with inflammation induced animal models. radiosynthesis of (99m) tc-tzb was assessed while changing ligand concentration, reducing agent concentration, ph, and reaction time while keeping radioactivity constant (~370 mbq). percent labeling of the resulting complex was measured using paper c ...201728181269
elongation factor p restricts salmonella's growth by controlling translation of a mg(2+) transporter gene during infection.when a ribosome translates mrna sequences, the ribosome often stalls at certain codons because it is hard to translate. consecutive proline codons are such examples that induce ribosome stalling and elongation factor p (ef-p) is required for the stalled ribosome to continue translation at those consecutive proline codons. we found that ef-p is required for translation of the mgtb gene encoding a mg(2+) transporter in the mgtcbr virulence operon from the intracellular pathogen salmonella enterica ...201728181542
draft genome sequences of two strains of salmonella enterica serovar typhimurium displaying different virulence in an experimental chicken model.salmonella enterica serovar typhimurium strains 22495 and 22792, obtained from wild birds, were found to display different virulence attributes in an experimental chicken model. closed genome sequences were assembled after sequencing with the roche 454 and illumina miseq platforms. an additional plasmid was present in the more virulent strain 22495.201728183752
salmonella effector sopd2 interferes with rab34 function.many intracellular pathogens have evolved highly specialized mechanisms to isolate themselves from the host cell's innate immune response while still obtaining the necessary nutrients to survive. salmonella utilizes type 3 secretion systems (t3sss) to deliver bacterial proteins called effectors, across the encompassing salmonella containing vacuole (scv) membrane, to subvert the host's membrane trafficking pathways and alter other cellular processes. the salmonella pathogenicity island (spi)-2 e ...201728185347
seeds of the wild progenitor of maize possess bacteria that antagonize foodborne pathogens.endophytes are microorganisms that inhabit plant tissues without causing disease. some endophytes help their hosts to combat pathogens. here we explored the hypothesis that the plant-derived foods consumed by humans and other animals host endophytes that also antagonize foodborne pathogens or food-rotting agents. our laboratory previously cultured a library of bacterial endophytes from different members of the maize/corn family (zea) including wild relatives. here, 190 of these endophytes were s ...201728186422
first detection of salmonella enterica serovar napoli in kennel dogs in italy. 201728188162
synthesis of l-cysteine derivatives containing stable sulfur isotopes and application of this synthesis to reactive sulfur metabolome.cysteine persulfide is an l-cysteine derivative having one additional sulfur atom bound to a cysteinyl thiol group, and it serves as a reactive sulfur species that regulates redox homeostasis in cells. here, we describe a rapid and efficient method of synthesis of l-cysteine derivatives containing isotopic sulfur atoms and application of this method to a reactive sulfur metabolome. we used bacterial cysteine syntheses to incorporate isotopic sulfur atoms into the sulfhydryl moiety of l-cysteine. ...201728189853
plant lectins conbr and cfl modulate expression toll-like receptors, pro-inflammatory cytokines and reduce the bacterial burden in macrophages infected with salmonella enterica serovar typhimurium.plant lectins have long been used in biomedical research as immunomodulators against tumor cells and microbial infections.201728190471
development of a high-throughput method to evaluate serum bactericidal activity using bacterial atp measurement as survival readout.serum bactericidal activity (sba) assay is the method of choice to evaluate the complement-mediated functional activity of both infection- and vaccine-induced antibodies. to perform a typical sba assay, serial dilutions of sera are incubated with target bacterial strains and complement. the conventional sba assay is based on plating on agar the sba reaction mix and counting the surviving bacterial colony forming units (cfu) at each serum dilution. even with automated colony counting, it is labor ...201728192483
salmonella inactivation during extrusion of an oat flour model food.little research exists on salmonella inactivation during extrusion processing, yet many outbreaks associated with low water activity foods since 2006 were linked to extruded foods. the aim of this research was to study salmonella inactivation during extrusion of a model cereal product. oat flour was inoculated with salmonella enterica serovar agona, an outbreak strain isolated from puffed cereals, and processed using a single-screw extruder at a feed rate of 75 kg/h and a screw speed of 500 rpm. ...201728192610
incidence of invasive salmonella disease in sub-saharan africa: a multicentre population-based surveillance study.available incidence data for invasive salmonella disease in sub-saharan africa are scarce. standardised, multicountry data are required to better understand the nature and burden of disease in africa. we aimed to measure the adjusted incidence estimates of typhoid fever and invasive non-typhoidal salmonella (ints) disease in sub-saharan africa, and the antimicrobial susceptibility profiles of the causative agents.201728193398
prevalence and molecular characterization of mcr-1-positive salmonella strains recovered from clinical specimens in china.the recently discovered colistin resistance-encoding element, mcr-1, adds to the list of antimicrobial resistance genes that rapidly erodes the antimicrobial efficacy of not only the commonly used antibiotics, but also the last line agents of carbapenems and colistin. this study investigated the prevalence of the mobile colistin resistance determinant mcr-1 in salmonella strains recovered from clinical settings in china, and the transmission potential of mcr-1-bearing mobile elements harbored by ...201728193662
different behavior of enteric bacteria and viruses in clay and sandy soils after biofertilization with swine digestate.enteric pathogens from biofertilizer can accumulate in the soil, subsequently contaminating water and crops. we evaluated the survival, percolation and leaching of model enteric pathogens in clay and sandy soils after biofertilization with swine digestate: phix-174, mengovirus (vmc0), salmonella enterica typhimurium and escherichia coli o157:h7 were used as biomarkers. the survival of vmc0 and phix-174 in clay soil was significantly lower than in sandy soil (it90 values of 10.520 ± 0.600 vs. 21. ...201728197137
development and validation of a cultural method for the detection and isolation of salmonella in cloves.detection of salmonella in some spices, such as cloves, remains a challenge due to their inherent antimicrobial properties. the purpose of this study was to develop an effective detection method for salmonella from spices using cloves as a model. two clove varieties, ceylon and madagascar, were used in the study. cloves were inoculated with salmonella enterica subsp. enterica serotypes montevideo, typhimurium, or weltevreden at about 1, 3, or 6 log cfu/25 g. two test portion sizes, 10 and 25 g, ...201728199150
antimicrobial resistance percentages of salmonella and shigella in seafood imported to jordan: higher percentages and more diverse profiles in shigella.this study determined the prevalence and antimicrobial resistance of human-specific ( shigella spp.) and zoonotic ( salmonella enterica ) foodborne pathogens in internationally traded seafood. sixty-four salmonella and 61 shigella isolates were obtained from 330 imported fresh fish samples from egypt, yemen, and india. the pathogens were isolated on selective media, confirmed by pcr, and tested for antimicrobial resistance. approximately 79 and 98% of the salmonella and shigella isolates, respec ...201728199151
diffusible substances from lactic acid bacterial cultures exert strong inhibitory effects on listeria monocytogenes and salmonella enterica serovar enteritidis in a co-culture model.food-borne infections cause huge economic and human life losses. listeria monocytogenes and salmonella enterica serovar enteritidis are among the top ranking pathogens causing such losses. control of such infections is hampered by persistent contamination of foods and food-processing environments, resistance of pathogens to sanitizing agents, existence of heterogeneous populations of pathogens (including culturable and viable but non-culturable cells) within the same food items, and inability to ...201728202007
epidemiological, molecular characterization and antibiotic resistance of salmonella enterica serovars isolated from chicken farms in egypt.salmonella is one of major causes of foodborne outbreaks globally. this study was conducted to estimate the prevalence, typing and antibiotic susceptibilities of salmonella enterica serovars isolated from 41 broiler chicken farms located in kafr el-sheikh province in northern egypt during 2014-2015. the clinical signs and mortalities were observed.201728203289
salmonella enterica serotype typhi bacteremia complicating pregnancy in the third trimester.background. salmonella enterica serotype typhi (s. typhi) is an anaerobic gram-negative enteric rod that causes infection when contaminated food or water is ingested and may cause illness in pregnancy. case. this is a patient who presented at 31 weeks' gestation with abdominal pain and fever and was diagnosed with s. typhi bacteremia. conclusion. s. typhi should be considered in febrile patients with recent travel presenting with abdominal discomfort with or without elevated liver enzymes.201728203469
comparative responses of chicken macrophages to infection with salmonella enterica serovars. 201728204713
enteric pathogens and their toxin-induced disruption of the intestinal barrier through alteration of tight junctions in chickens.maintaining a healthy gut environment is a prerequisite for sustainable animal production. the gut plays a key role in the digestion and absorption of nutrients and constitutes an initial organ exposed to external factors influencing bird's health. the intestinal epithelial barrier serves as the first line of defense between the host and the luminal environment. it consists of a continuous monolayer of intestinal epithelial cells connected by intercellular junctional complexes which shrink the s ...201728208612
regulation of nrf operon expression in pathogenic enteric bacteria: sequence divergence reveals new regulatory complexity.the escherichia coli k-12 nrf operon encodes a periplasmic nitrite reductase, the expression of which is driven from a single promoter, pnrf. expression from pnrf is activated by the fnr transcription factor in response to anaerobiosis and further increased in response to nitrite by the response regulator proteins, narl and narp. fnr-dependent transcription is suppressed by the binding of two nucleoid associated proteins, ihf and fis. as fis levels increase in cells grown in rich medium, the pos ...201728211111
kinneretia thg-sqi4 mediated biosynthesis of silver nanoparticles and its antimicrobial efficacy.simple, facile, effective approach for the biosynthesis of silver nanoparticles using kinneretia species and its antimicrobial activity against human pathogens has been demonstrated in this study. kinneretia thg-sqi4 has been isolated from soil sample collected from shangqui, china. the synthesized nanoparticles were characterized by ultraviolet-visible spectrophotometry (uv-vis), field emission transmission electron microscopy (fe-tem), energy dispersive x-ray spectroscopy (edx), elemental mapp ...201728211298
scarless deletion of up to seven methyl-accepting chemotaxis genes with an optimized method highlights key function of chem in salmonella typhimurium.site-directed scarless mutagenesis is an essential tool of modern pathogenesis research. we describe an optimized two-step protocol for genome editing in salmonella enterica serovar typhimurium to enable multiple sequential mutagenesis steps in a single strain. the system is based on the λ red recombinase-catalyzed integration of a selectable antibiotics resistance marker followed by replacement of this cassette. markerless mutants are selected by expressing the meganuclease i-scei which induces ...201728212413
pathogen biofilm formation on cantaloupe surface and its impact on the antibacterial effect of lauroyl arginate ethyl.pathogen biofilm at fruit surface may pose a particular risk to food safety. in this study, the biofilms of listeria monocytogenes v7 and salmonella enterica serovar typhimurium atcc 13311 on cantaloupe fruit surface were visualized, and the resistance of biofilms against lauroyl arginate ethyl (lae, an antibacterial compound) was evaluated. each bacterium was inoculated on isolated cantaloupe rind surfaces at 10(5)-10(6) cfu/cm(2) and after incubation for 2, 12, 24, and 48 h, the surfaces were ...201728213018
the locus of heat resistance (lhr) mediates heat resistance in salmonella enterica, escherichia coli and enterobacter cloacae.enterobacteriaceae comprise food spoilage organisms as well as food-borne pathogens including escherichia coli. heat resistance in e. coli was attributed to a genomic island called the locus of heat resistance (lhr). this genomic island is also present in several other genera of enterobacteriaceae, but its function in the enteric pathogens salmonella enterica and enterobacter cloacae is unknown. this study aimed to determine the frequency of the lhr in food isolates of e. coli, and its influence ...201728213040
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