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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
salmonella enterica serotype typhi from a case of empyema. 201123785888
vaccination of chickens with spi1-lon and spi1-lon-flic mutant of salmonella enterica serovar enteritidis.the prevalence of salmonella enterica serovar enteritidis is gradually decreasing in poultry flocks in the eu, which may result in the demand for a vaccine that allows for the differentiation of vaccinated flocks from those infected by wild-type s. enteritidis. in this study, we therefore constructed a (salmonella pathogenicity island 1) spi1-lon mutant with or without flic encoding for s. enteritidis flagellin. the combination of spi1-lon mutations resulted in attenuated but immunogenic mutant ...201323785484
first report of liver abscess caused by salmonella enterica serovar dublin.this is the first reported case of liver abscess attributable to salmonella serovar dublin infection and also the fourth case of salmonella liver abscess complicated with hepatocellular carcinoma reported since 1990. drainage combined with intravenous antibiotics resulted in improvement, but recovery regressed again. subsequent hepatic left lobectomy led to full recovery.201323784127
unsaturated long chain free fatty acids are input signals of the salmonella enterica phop/phoq regulatory system.the salmonella enterica serovar typhimurium phop/phoq system has largely been studied as a paradigmatic two-component regulatory system not only to dissect structural and functional aspects of signal transduction in bacteria but also to gain knowledge about the versatile devices that have evolved allowing a pathogenic bacterium to adjust to or counteract environmental stressful conditions along its life cycle. mg(2+) limitation, acidic ph, and the presence of cationic antimicrobial peptides have ...201323782700
salmonella enterica serotype choleraesuis infection of the knee and femur in a nonbacteremic diabetic patient.osteoarticular infections caused by salmonella are rare. the rates of osteomyelitis and septic arthritis due to salmonella are estimated to be less than 1% and 0.1%-0.2%, respectively (kato et al., 2012). salmonella enterica serotype choleraesuis is a nontyphoidal salmonella, highly pathogenic in humans, usually causing septicemic disease with little or no intestinal involvement. serotype choleraesuis accounts for a small percentage of published studies of salmonella infections in the united sta ...201323781356
β-1,3/1,6-glucan alleviated intestinal mucosal barrier impairment of broiler chickens challenged with salmonella enterica serovar typhimurium.this study investigated the protective effect of β-1,3/1,6-glucan on gut morphology, intestinal epithelial tight junctions, and bacterial translocation of broiler chickens challenged with salmonella enterica serovar typhimurium. ninety salmonella-free arbor acre male broiler chickens were randomly divided into 3 groups: negative control group (nc), salmonella typhimurium-infected positive group (pc), and the salmonella typhimurium-infected group with dietary 100 mg/kg of β-1,3/1,6-glucan supplem ...201323776263
a colanic acid operon deletion mutation enhances induction of early antibody responses by live attenuated salmonella vaccine strains.colanic acid (ca) is a common exopolysaccharide produced by many genera in the enterobacteriaceae. it is critical for biofilm formation on hep-2 cells and on chicken intestinal tissue by salmonella. in this study, we generated different ca synthesis gene mutants and evaluated the immune responses induced by these mutants. one of these mutations, δ(wza-wcam)8, which deleted the whole operon for ca synthesis, was introduced into two salmonella vaccine strains attenuated by auxotrophic traits or by ...201323774599
identification of salmonella enterica serovar pullorum antigenic determinants expressed in vivo.salmonella enterica serovar pullorum affecting poultry causes pullorum disease and results in severe economic loss in the poultry industry. currently, it remains a major threat in countries with poor poultry surveillance and no efficient control measures. as s. pullorum could induce strong humoral immune responses, we applied an immunoscreening technique, the in vivo-induced antigen technology (iviat), to identify immunogenic bacterial proteins expressed or upregulated during s. pullorum infecti ...201323774596
environmental salmonella in agricultural fair poultry exhibits in colorado.salmonella enterica is a common zoonotic pathogen in humans. transmission typically occurs through consumption of contaminated food products or contact with infected animals, including poultry or their environment. the objective of this study was to estimate the frequency of salmonella contamination in the environment in poultry exhibits at agricultural fairs. samples were collected from cages, feed, floors and tables in the exhibit and cultured for salmonella. at least one environmental sample ...201423773691
evidence of metabolic switching and implications for food safety from the phenome(s) of salmonella enterica serovar typhimurium dt104 cultured at selected points across the pork production food chain.salmonella enterica serovar typhimurium dt104 is a recognized food-borne pathogen that displays a multidrug-resistant phenotype and that is associated with systemic infections. at one extreme of the food chain, this bacterium can infect humans, limiting the treatment options available and thereby contributing to increased morbidity and mortality. although the antibiotic resistance profile is well defined, little is known about other phenotypes that may be expressed by this pathogen at key points ...201323770904
attenuated salmonella enterica serovar typhimurium lacking the znuabc transporter: an efficacious orally-administered mucosal vaccine against salmonellosis in pigs.we have recently demonstrated that an attenuated strain of salmonella enterica serovar typhimurium unable to synthesize the zinc transporter znuabc (s. typhimurium δznuabc), is able to protect mice against systemic and enteric salmonellosis and is safe in pigs. here, we have tested the protective effects of s. typhimurium δznuabc in pigs. resistance to challenge with the fully virulent strain s. typhimurium atcc 14028 was assessed in animals vaccinated with s. typhimurium δznuabc (two dosages te ...201323770333
occurrence of plasmid-mediated quinolone resistance determinants and rmtb gene in salmonella enterica serovar enteritidis and typhimurium isolated from food-animal products in tunisia.four hundred and thirty salmonella isolates, recovered from various food-animal products, were tested for nalidixic acid resistance, plasmid-mediated quinolone resistance, and genetic relationship. one hundred fifteen isolates (113 salmonella serovar enteritidis and two salmonella serovar typhimurium isolates) of 430 (26.7%) salmonella isolates exhibited nalidixic acid resistance. polymerase chain reaction screening for qnra, qnrb, qnrs, qepa (encoding fluoroquinolones resistance) and rmtb (enco ...201323767853
low prevalence of salmonella enterica in australian wildlife.a total of 2489 wildlife hosts from australia were sampled in order to determine the fraction of hosts that harboured salmonella enterica as a dominant member of the host's enteric community. hosts sampled included fish, frogs, reptiles, birds and mammals from the four main climatic regions of australia: desert, grassland, temperate and tropical. salmonella enterica was predominately isolated from reptiles, in particular, lizards. it was also isolated from mammals, though not from any fish, frog ...201023766252
epidemic multidrug-resistant (mdr-ampc) salmonella enterica serovar newport strains contain three phage regions and a mdr resistance plasmid.multidrug-resistant (mdr-ampc) salmonella enterica serovar newport has caused serious disease in animals and humans in north america, whereas in the uk s. enterica serovar newport is not associated with severe disease and usually sensitive to antibiotics; mdr s. newport (not ampc) strains have only been isolated from poultry. we found that uk poultry strains belonged to mlst type st166 and were distinct from cattle isolates for being able to utilize d-tagotose and when compared by pulsed-field g ...201023766073
high pressure homogenization vs heat treatment: safety and functional properties of liquid whole egg.this research investigated the potential of multi-pass homogenization treatment for the inactivation of salmonella enterica serovar enteritidis inoculated at different levels in liquid whole egg (lwe) comparing the efficacy of this treatment with a traditional thermal one performed at 65 °c. moreover, the effects of high pressure treatment (hph) on structural and functional properties such as viscosity, microstructure and foaming abilities of lwe were investigated. the data obtained suggested th ...201323764221
evaluation of the efficiency of synthesized efflux pump inhibitors on salmonella enterica ser. typhimurium cells.multidrug efflux pump inhibitors have a great potential as pharmacological agents that increase the drug susceptibility of bacterial pathogens. our study was focused on the synthesis and evaluation of the efficiency of resistance-nodulation-division (rnd) family efflux pump inhibitors. the efficiency of these inhibitors was investigated on salmonella enterica ser. typhimurium cells using tetraphenylphosphonium (tpp(+) ) and ethidium cations as the efflux pump substrates. results of our study ind ...201323763959
human single-chain urokinase is activated by the omptins pgte of salmonella enterica and pla of yersinia pestis despite mutations of active site residues.fibrinolysis is important in cell migration and tightly regulated by specific inhibitors and activators; of the latter, urokinase (upa) associates with enhancement of cell migration. active upa is formed through cleavage of the single-chain upa (scupa). the salmonella enterica strain 14028r cleaved human scupa at the peptide bond lys158-ile159, the site cleaved also by the physiological activator human plasmin. the cleavage led to activation of scupa, while no cleavage or activation were detecte ...201323763588
cellulose mediates attachment of salmonella enterica serovar typhimurium to tomatoes.fresh fruit and vegetables are important components of a healthy and balanced diet. however, they are increasingly being recognized as important vehicles for transmission of human pathogens that were traditionally classified as zoonotic. there is a significant gap in our knowledge and understanding of the mechanisms by which human pathogens colonize and survive on or in fruits and vegetables. in this study we investigated the binding of salmonella enterica to tomato fruits (solanum lycopersicum) ...201123761337
intestinal and chronic infections: salmonella lifestyles in hostile environments.the main disease syndromes caused by salmonella serovars in immunocompetent individuals are gastroenteritis and typhoid fever. these syndromes differ with regard to the host niches in which salmonella serovars grow and survive to ensure their transmission. during gastroenteritis, non-typhoidal salmonella serovars such as salmonella enterica serovar typhimurium (s. typhimurium) use their virulence factors to elicit acute intestinal inflammation, thereby creating a novel luminal niche. reactive ox ...201123761329
genomic fingerprinting and serotyping of salmonella from galápagos iguanas demonstrates island differences in strain diversity.salmonella carriage patterns in wild and captive reptiles suggest that both geographical proximity and host ecological differences may determine bacterial diversity among reptile populations. in this study, we explore the relative importance of these factors on salmonella diversity in free-living galápagos iguanas. we isolated salmonella enterica from marine iguanas (amblyrhynchus cristatus) and land iguanas (conolophus subcristatus and c. pallidus) living on two islands (plaza sur and santa fe) ...201123761248
spontaneous non-rdar mutations increase fitness of salmonella in plants.proliferation of human enteric pathogens within alternate hosts, like plants, leads to temporal changes in gene expression and also selects for the phenotypic variants of the enterics that are presumed to be more fit within plants. human enteric pathogens recovered from produce-borne outbreaks exhibit peculiar phenotypes, for example many of them do not display the rdar (red dry and rough) phenotype. the non-rdar phenotype results from mutations in cellulose and/or curli synthesis or regulation. ...201223760832
synthesis, antibacterial and thermal studies of cellulose nanocrystal stabilized zno-ag heterostructure nanoparticles.synthesis of zno-ag heterostructure nanoparticles was carried out by a precipitation method with cellulose nanocrystals (cncs) as a stabilizer for antimicrobial and thermal studies. zno-ag nanoparticles were obtained from various weight percentages of added agno₃ relative to zn precursors for evaluating the best composition with enhanced functional properties. the zno-ag/cncs samples were characterized systematically by tem, xrd, uv, tga and dtg. from the tem studies we observed that zno-ag hete ...201323760028
a dna microarray for the versatile diagnosis of infectious diarrhea.several bacteria, viruses, and parasites cause diarrhea as coinfecting pathogens. we designed a dna microarray comprising 60-bp probes spotted 194 times for the multiplex detection of 33 enteropathogenic bacteria and seven enteropathogenic viruses, and the archaeon methanobrevibacter smithii was used as an internal positive control. nine pathogen-free stool specimens were used as negative controls. one of these control specimens was further spiked with salmonella enterica as a positive control. ...201323758523
characterization of salmonella isolated from captive and free-living snakes in germany.reptiles are well-known reservoirs of salmonella spp. and cases of reptile-associated salmonellosis (ras) are increasing since reptiles are becoming more popular as pets. in the present study, the presence, distribution and prevalence of serovars of salmonella was investigated in captive snakes (n = 87) and in free-living snakes (n = 87) in germany. a total of 43 s. enterica-isolates were recovered from organ samples and cloacal swabs, predominantly belonging to the subspecies diarizonae (iiib) ...201323758035
salmonella infections in reptiles--prevalence, serovar spectrum and impact on animal health.in a seven year study, 235 lizards, 193 snakes and 111 chelonians were tested for the occurrence of salmonella enterica. the material for analysis consisted of 251 faecal samples from reptiles suffering from diarrhoea and 288 carcasses of perished or euthanized reptiles. the carcasses were dissected and examined pathohistologically. a total of 35.3% of the lizards, 47.2% of the snakes and 11.7% of the chelonians were found to be salmonella-positive. systemic salmonella infection was detected in ...201323758034
root internalization, transport and in-planta survival of salmonella enterica serovar newport in sweet basil.it is now acknowledged that food-borne pathogens present in the irrigation water or soil can become associated with crop plants in the field, penetrate internal plant tissues via the root, translocate and survive inside plants. only little information is available concerning interaction between enteric pathogens and plants. the present study evaluated the potential for contamination of the aromatic plant, sweet basil during cultivation, by salmonella enterica serovar newport. root internalizatio ...201223757144
the systemic immune state of super-shedder mice is characterized by a unique neutrophil-dependent blunting of th1 responses.host-to-host transmission of a pathogen ensures its successful propagation and maintenance within a host population. a striking feature of disease transmission is the heterogeneity in host infectiousness. it has been proposed that within a host population, 20% of the infected hosts, termed super-shedders, are responsible for 80% of disease transmission. however, very little is known about the immune state of these super-shedders. in this study, we used the model organism salmonella enterica sero ...201323754944
salmonella septic arthritis of the knees in a patient with systemic lupus erythematosus.hematogenous salmonella osteomyelitis is uncommon in immunocompetent hosts, but occurs with some regularity in immunosuppressed patients affected by systemic lupus erythematosus (sle). surgical debridement with resection of compromised tissue is central to the surgical management of osteomyelitis. persistence of septic arthropathy may result from inadequate debridement, areas of osteonecrosis (on), and an abnormal cellular and humoral dysregulation characteristic of sle. we describe a 53-year-ol ...201323753601
role of murine intestinal interleukin-1 receptor 1-expressing lymphoid tissue inducer-like cells in salmonella infection.interleukin (il)-1 signaling plays a critical role in intestinal immunology. here, we report that the major population of intestinal lamina propria lymphocytes expressing il-1 receptor 1 (il-1r1) is the lymphoid tissue inducer (lti)-like cell, a type of innate lymphoid cell. these cells are significant producers of il-22, and this il-22 production depends on il-1r1 signaling. lti-like cells are required for defense against salmonella enterica serovar typhimurium. moreover, colonic lti-like cell ...201323750260
oxidoreductases that act as conditional virulence suppressors in salmonella enterica serovar typhimurium.in salmonella enterica serovar typhimurium, oxidoreductases of the thioredoxin superfamily contribute to bacterial invasiveness, intracellular replication and to the virulence in balb/c mice as well as in the soil nematode caenorhabditis elegans. the scsabcd gene cluster, present in many but not all enteric bacteria, codes for four putative oxidoreductases of the thioredoxin superfamily. here we have analyzed the potential role of the scs genes in oxidative stress tolerance and virulence in s. t ...201323750221
length control of the flagellar hook in a temperature-sensitive flge mutant of salmonella enterica serovar typhimurium.the flagellar hook is a short, curved, extracellular structure located between the basal body and the filament. the hook is composed of the flge protein. in this study, we analyzed flagellum assembly in a temperature-sensitive flge mutant of salmonella enterica serovar typhimurium. when the mutant cells were grown at 30°c, they produced flagella of a normal length (71% of the population) and short hooks without filaments (26%). at 37°c, 70% of the basal bodies lacked hooks, and intact flagella m ...201323749974
in the absence of rida, endogenous 2-aminoacrylate inactivates alanine racemases by modifying the pyridoxal 5'-phosphate cofactor.members of the rida (yjgf/yer057c/uk114) protein family are broadly conserved across the domains of life. in vitro, these proteins deaminate 3- or 4-carbon enamines that are generated as mechanistic intermediates of pyridoxal 5'-phosphate (plp)-dependent serine/threonine dehydratases. the three-carbon enamine 2-aminoacrylate can inactivate some enzymes by forming a covalent adduct via a mechanism that has been well characterized in vitro. the biochemical activity of rida suggested that the pheno ...201323749972
identification and characterization of a novel flagellum-dependent salmonella-infecting bacteriophage, ieps5.a novel flagellatropic phage of salmonella enterica serovar typhimurium, called ieps5, was isolated and characterized. ieps5 has an icosahedral head and a long noncontractile tail with a tail fiber. genome sequencing revealed a double-stranded dna of 59,254 bp having 73 open reading frames (orfs). to identify the receptor for ieps5, tn5 transposon insertion mutants of s. typhimurium sl1344 that were resistant to the phage were isolated. all of the phage-resistant mutants were found to have mutat ...201323747700
proposed model for the high rate of rearrangement and rapid migration observed in some inca/c plasmid lineages.inca/c plasmids are a class of plasmids from the enterobacteriaceae that are relatively large (49 to >180 kbp), that are readily transferred by conjugation, and that carry multiple antimicrobial resistance genes. reconstruction of the phylogeny of these plasmids has been difficult because of the high rate of remodeling by recombination-mediated horizontal gene transfer (hgt). we hypothesized that evaluation of nucleotide polymorphisms relative to the rate of hgt would help to develop a clock to ...201323747695
residues of a proposed gate region in type i atp-binding cassette import systems are crucial for function as revealed by mutational analysis.the type i atp-binding cassette (abc) importer for positively charged amino acids of the thermophilic bacterium geobacillus stearothermophilus consists of the extracellular solute binding protein, artj, and a homodimer each of the transmembrane subunit, artm, and the nucleotide-binding and -hydrolyzing subunit, artp. we have investigated the functional consequences of mutations affecting conserved residues from two peptide regions in artm, recently proposed to form a 'gate' by which access of a ...201323747295
the teta gene decreases tigecycline sensitivity of salmonella enterica isolates.to determine the association of tetracycline resistance determinants with tigecycline sensitivity, tetracycline-resistant salmonella spp. isolated from clinical and food samples were tested for the presence of tetracycline resistance determinants, tigecycline sensitivity, and the impact of teta on tigecycline resistance. in addition, the impacts of multiple resistance mechanisms on tigecycline resistance were determined using an isolate with ramr mutation. of the 49 tetracycline-resistant salmon ...201323746717
chromosomal excision of a new pathogenicity island modulates salmonella virulence in vivo.although the excision of unstable pathogenicity islands is a phenomenon that has been described for several virulent bacteria, whether this process directly affects the capacity of these microorganisms to cause disease in their hosts remains unknown. salmonella enterica serovar enteritidis (s. enteritidis) is an enterobacterium that harbors several unstable pathogenicity islands that can excise from the main bacterial chromosome. here we have evaluated whether excision of one of these pathogenic ...201323746206
[therapeutic intervention alternatives in cancer, using attenuated live bacterial vectors: salmonella enterica as a carrier of heterologous molecules].salmonella enterica is a facultative anaerobic bacteria, whose ability to colonize antigen-presenting cells (apcs) such as dendritic cells and macrophages, has allowed its successful use as an alive, attenuated bacterial vector for vaccination. salmonella enterica elicits efficient cellular, humoral and mucosal immune responses, against heterologous antigens including viruses, parasites, other bacterial species and tumor-associated antigens, since it is capable of delivering these antigens to ce ...201523745445
contribution of different mechanisms to the resistance to fluoroquinolones in clinical isolates of salmonella enterica.to study the potential factors include gene mutation, efflux pump and alteration of permeability associated with quinolone-resistance of salmonella enterica strains isolated from patients with acute gastroenteritis and to evaluate the degree of synergistic activity of efflux pump inhibitors when combined with ciprofloxacin against resistant isolates.201323742803
identification of the yfgf mase1 domain as a modulator of bacterial responses to aspartate.complex 3'-5'-cyclic diguanylic acid (c-di-gmp) responsive regulatory networks that are modulated by the action of multiple diguanylate cyclases (dgc; ggdef domain proteins) and phosphodiesterases (pde; eal domain proteins) have evolved in many bacteria. yfgf proteins possess a membrane-anchoring domain (mase1), a catalytically inactive ggdef domain and a catalytically active eal domain. here, sustained expression of the salmonella enterica spp. enterica ser. enteritidis yfgf protein is shown to ...201323740576
co-occurrence of acssut and cephalosporin resistance phenotypes is mediated by int1-associated elements in nontyphoidal salmonella enterica from human infections in spain.a screening of antimicrobial resistance and its genetic determinants has been performed on 300 salmonella enterica isolates collected during 2004-2008 from human infections in spain. salmonella typhimurium and salmonella enteritidis were the major serotypes, which were found with similar frequencies covering 80% of the bacterial collection. salmonella typhimurium isolates frequently shared low susceptibility to antimicrobials of the penta-resistance phenotype (acssut) and/or cephalosporin resist ...201323738829
spread of oqxab in salmonella enterica serotype typhimurium predominantly by inchi2 plasmids.to investigate the prevalence and genetic environment of the multiresistance gene oqxab in salmonella enterica serotype typhimurium isolated from food-producing animals.201323737490
ciprofloxacin-resistant salmonella enterica serovar kentucky in canada.we report emergence of ciprofloxacin-resistant salmonella enterica serovar kentucky in canada during 2003-2009. all isolates had similar macrorestriction patterns and were multilocus sequence type st198, which has been observed in europe and africa. ciprofloxacin-resistant s. enterica serovar kentucky represents 66% of all ciprofloxacin-resistant nontyphoidal salmonella sp. isolates observed in canada since 2003.201323735312
use of a bacteriophage cocktail to control salmonella in food and the food industry.the use of lytic bacteriophages for the biocontrol of food-borne pathogens in food and in the food industry is gaining increasing acceptance. in this study, the effectiveness of a bacteriophage cocktail composed of three different lytic bacteriophages (uab_phi 20, uab_phi78, and uab_phi87) was determined in four different food matrices (pig skin, chicken breasts, fresh eggs, and packaged lettuce) experimentally contaminated with salmonella enterica serovar typhimurium and s. enterica serovar ent ...201323735218
assignment of serotype to salmonella enterica isolates obtained from poultry and their environment in southern brazil.to assess diversity of salmonella enterica serotypes present in poultry and their environment from southern brazil, the kauffmann-white-le minor (kwl) scheme was used to serotype a total of 155 isolates. isolates were then re-examined with nested pcr and sequencing of the dkgb-linked intergenic sequence ribotyping (isr) region that assesses single nucleotide polymorphisms occurring around a 5s ribosomal gene. serotypes identified were heidelberg (40·6%), enteritidis (34·2%), hadar (8·4%), typhim ...201323734786
genetic mechanisms of antimicrobial resistance identified in salmonella enterica, escherichia coli, and enteroccocus spp. isolated from u.s. food animals.the prevalence of antimicrobial resistance (ar) in bacteria isolated from u.s. food animals has increased over the last several decades as have concerns of ar foodborne zoonotic human infections. resistance mechanisms identified in u.s. animal isolates of salmonella enterica included resistance to aminoglycosides (e.g., alleles of aacc, aada, aadb, ant, apha, and strab), β-lactams (e.g., bla cmy-2, tem-1, pse-1), chloramphenicol (e.g., flor, cmla, cat1, cat2), folate pathway inhibitors (e.g., al ...201323734150
chronological change of resistance to β-lactams in salmonella enterica serovar infantis isolated from broilers in japan.epidemiologic surveillance study was conducted in southern japan to determine the antimicrobial resistance phenotypes and characterize the β-lactamase genes and the plasmids harboring these genes in salmonella enterica serovar infantis (s. infantis) isolates from broilers. between january, 2007 and december, 2008, a total of 1,472 fecal samples were collected and examined at the laboratory of veterinary public health, kagoshima university, japan. in 93 (6.3%) isolates recovered, 33 (35.5%) isola ...201323734146
distribution of six effector protein virulence genes among salmonella enterica enterica serovars isolated from children and their correlation with biofilm formation and antimicrobial resistance.salmonella enterica enterica encodes a variety of virulence factors. among them, the type iii secretion system (ttss) encoded in the salmonella pathogenicity islands (spis) is required for induction of proinflammatory responses, invasion of intestinal epithelial cells, induction of cell death in macrophages, and elicitation of diarrhea. the presence of the effector protein genes sopb, sopd, sope, sope2, avra, and sptp of the spis was analyzed in 194 s. enterica enterica strains belonging to 19 s ...201323733519
protein signatures that promote operator selectivity among paralog merr monovalent metal ion regulators.two paralog transcriptional regulators of the merr family, cuer and gols, are responsible for monovalent metal ion sensing and resistance in salmonella enterica. although similar in sequence and also in their target binding sites, these proteins differ in signal detection and in the set of target genes they control. recently, we demonstrated that selective promoter recognition depends on the presence of specific bases located at positions 3' and 3 within the operators they interact with. here, w ...201323733186
potential therapeutic anti-tumor effect of a salmonella-based vaccine.one of the major obstacles to achieving complete eradication of tumors, even in the presence of circulating tumor-specific immunity, is the tumor-induced immunosuppressive environment, which includes myeloid-derived suppressor cells and regulatory t cells. attenuated microorganisms have emerged as candidates for a novel anti-cancer approach in which they enhance anti-cancer immunity by boosting the innate immune system. herein, we will discuss current innate-immunity activating strategies for an ...201323733040
new delhi metallo-β-lactamase-producing enterobacteriaceae, united states.we characterized 9 new delhi metallo-β-lactamase-producing enterobacteriaceae (5 klebsiella pneumoniae, 2 escherichia coli, 1 enterobacter cloacae, 1 salmonella enterica serovar senftenberg) isolates identified in the united states and cultured from 8 patients in 5 states during april 2009-march 2011. isolates were resistant to β-lactams, fluoroquinolones, and aminoglycosides, demonstrated mics ≤1 µg/ml of colistin and polymyxin, and yielded positive metallo-β-lactamase screening results. eight ...201323731823
survival of acid adapted and non-acid adapted salmonella typhimurium in pasteurized orange juice and yogurt under different storage temperatures.the survival capacity of salmonella enterica serovar typhimurium acid adapted and non-acid adapted cells was monitored in pasteurized yogurt (ph 4.1) and orange juice (ph 3.6) during storage at different temperatures (4, 10, 25 and 37 ). acid adapted and non-acid adapted cells were obtained by means of their growth for 36 h in brain heart infusion broth acidified at ph 4.8 with citric acid and buffered (ph 7.0) brain heart infusion broth, respectively. s. typhimurium showed a great ability to su ...201323729421
increased water activity reduces the thermal resistance of salmonella enterica in peanut butter.increased water activity in peanut butter significantly (p < 0.05) reduced the heat resistance of desiccation-stressed salmonella enterica serotypes treated at 90 °c. the difference in thermal resistance was less notable when strains were treated at 126 °c. using scanning electron microscopy, we observed minor morphological changes of s. enterica cells resulting from desiccation and rehydration processes in peanut oil.201323728806
crystal structure of the periplasmic disulfide-bond isomerase dsbc from salmonella enterica serovar typhimurium and the mechanistic implications.the disulfide-bond isomerase dsbc plays a crucial role in the folding of bacterial proteins in the periplasmic space. dsbc has a v-shaped dimeric structure with two domains, and cys98 in the c-terminal domain attacks inappropriate disulfide bonds in substrate proteins due to its high nucleophilic activity. in this article, we present the crystal structure of dsbc from salmonella enterica serovar typhimurium. we evaluated the conserved residues asp95 and arg125, which are located close to cys98. ...201323726983
validation of a predictive model for survival and growth of salmonella typhimurium dt104 on chicken skin for extrapolation to a previous history of frozen storage.the u.s. department of agriculture's tertiary pathogen modeling program (pmp) model for survival and growth of salmonella enterica ser. typhimurium definitive type 104 (dt104) on chicken skin stored for 0 to 8 h at 5 to 50°c was evaluated for its ability to predict survival and growth of the same organism on chicken skin after frozen storage for 6 days at -20°c. experimental design and methods used to collect data for model development (dependent data) were the same as those used to collect data ...201323726201
effect of lime juice on vibrio parahaemolyticus and salmonella enterica inactivation during the preparation of the raw fish dish ceviche.ceviche is a raw fish dish common in peru and other latin american counties. the most characteristic feature of ceviche is the use of lime juice for marinating or "cooking" the raw fish. confirmed cases of cholera in peru, new jersey, and florida have been associated with ceviche. although the effect of organic acids on pathogenic bacteria has been well characterized, few data exist on the effect of these acids in seafood systems. the objective of the study was to evaluate the effects of lime ju ...201323726199
comparative genomics of salmonella enterica serovars derby and mbandaka, two prevalent serovars associated with different livestock species in the uk.despite the frequent isolation of salmonella enterica sub. enterica serovars derby and mbandaka from livestock in the uk and usa little is known about the biological processes maintaining their prevalence. statistics for salmonella isolations from livestock production in the uk show that s. derby is most commonly associated with pigs and turkeys and s. mbandaka with cattle and chickens. here we compare the first sequenced genomes of s. derby and s. mbandaka as a basis for further analysis of the ...201323725633
common evolutionary origin for the rotor domain of rotary atpases and flagellar protein export apparatus.the v1- and f1- rotary atpases contain a rotor that rotates against a catalytic a3b3 or α3β3 stator. the rotor f(1-γ) or v1-df is composed of both anti-parallel coiled coil and globular-loop parts. the bacterial flagellar type iii export apparatus contains a v1/f1-like atpase ring structure composed of flii6 homo-hexamer and flij which adopts an anti-parallel coiled coil structure without the globular-loop part. here we report that flij of salmonella enterica serovar typhimurium shows a rotor li ...201323724081
crystallization and preliminary x-ray analysis of the flagellar motor `brake' molecule ycgr with c-di-gmp from escherichia coli.in escherichia coli and salmonella enterica, bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-gmp), a ubiquitous bacterial second-messenger molecule that participates in many cellular processes, can regulate flagellar motor speed and reduce cell swimming velocity by binding to the pilz-containing protein ycgr. here, the crystallization and preliminary x-ray crystallographic analysis of ycgr with c-di-gmp are reported. the crystals diffracted to 2.3 å resolution and belonged to space grou ...201323722848
national outbreaks of salmonella infection in the uk, 2000-2011.over a 12-year period, the health protection agency's (now public health england's) department of gastrointestinal and emerging infections (gezi) investigated over 100 potential national outbreaks of salmonella enterica. these ranged from a cluster of cases requiring data interrogation and monitoring of the situation, to full blown case-control studies involving hundreds of interviews, many staff, multi-agency collaboration and the media. vehicles of infection ranged from the usual suspects of c ...201423721866
highly drug-resistant salmonella enterica serotype kentucky st198-x1: a microbiological study.salmonella enterica is a major global food-borne pathogen, causing life-threatening infections. ciprofloxacin and extended-spectrum cephalosporins (escs) are the drugs of choice for severe infections. we previously reported a ciprofloxacin-resistant s. enterica serotype kentucky (s kentucky) st198-x1 strain that emerged in egypt and spread throughout africa and the middle east from 2002 to 2008. we aimed to monitor recent trends in the location of transmission and antimicrobial resistance of thi ...201323721756
first report of salmonella enterica serovar infantis in common swifts (apus apus).forty common swifts (apus apus), synanthropic birds living in an urban environment closely with humans and other animals, were hospitalized in the public veterinary hospital of the regional reference center of urban veterinary hygiene located in naples, campania region, italy. each bird was sampled for bacteriological analyses. out of 40 common swifts examined, eight were found positive for salmonella enterica serovar infantis although no sign of salmonellosis (e.g. diarrhoea) was shown. this is ...201323721074
[search for new potential rna thermometers in the salmonella enterica genome]. 201323718050
genome-wide analysis of the salmonella fis regulon and its regulatory mechanism on pathogenicity islands.fis, one of the most important nucleoid-associated proteins, functions as a global regulator of transcription in bacteria that has been comprehensively studied in escherichia coli k12. fis also influences the virulence of salmonella enterica and pathogenic e. coli by regulating their virulence genes, however, the relevant mechanism is unclear. in this report, using combined rna-seq and chromatin immunoprecipitation (chip)-seq technologies, we first identified 1646 fis-regulated genes and 885 fis ...201323717649
circadian clock regulates the host response to salmonella.organisms adapt to day-night cycles through highly specialized circadian machinery, whose molecular components anticipate and drive changes in organism behavior and metabolism. although many effectors of the immune system are known to follow daily oscillations, the role of the circadian clock in the immune response to acute infections is not understood. here we show that the circadian clock modulates the inflammatory response during acute infection with the pathogen salmonella enterica serovar t ...201323716692
computational analysis of bacterial rna-seq data.recent advances in high-throughput rna sequencing (rna-seq) have enabled tremendous leaps forward in our understanding of bacterial transcriptomes. however, computational methods for analysis of bacterial transcriptome data have not kept pace with the large and growing data sets generated by rna-seq technology. here, we present new algorithms, specific to bacterial gene structures and transcriptomes, for analysis of rna-seq data. the algorithms are implemented in an open source software system c ...201323716638
cgmolluscidin, a novel dibasic residue repeat rich antimicrobial peptide, purified from the gill of the pacific oyster, crassostrea gigas.a 5.5 kda antimicrobial peptide consisting of 55 amino acids, cgmolluscidin, was purified from the acidified gill extract of the pacific oyster, crassostrea gigas, by ion-exchange and c18 reversed-phase high performance liquid chromatography. by comparing the n-terminal amino acid sequences and the molecular weight of this peptide with those of other known antimicrobial peptides, it has been revealed that this peptide had no homology with any known peptides. cgmolluscidin showed potent antimicro ...201323711469
emergence of multidrug-resistant salmonella enterica serotype 4,[5],12:i:- involving human cases in canada: results from the canadian integrated program on antimicrobial resistance surveillance (cipars), 2003-10.over the last decade, a marked increase in salmonella enterica serotype 4,[5],12:i:- with a core resistance to ampicillin, streptomycin, sulphonamides and tetracycline (assut) has been observed in europe. this study describes the emergence and characterization of isolates of multidrug-resistant salmonella 4,[5],12:i:- in canada.201323710071
evaluation of aerated steam treatment of alfalfa and mung bean seeds to eliminate high levels of escherichia coli o157:h7 and o178:h12, salmonella enterica, and listeria monocytogenes.sprouts contaminated with human pathogens are able to cause food-borne diseases due to the favorable growth conditions for bacteria during germination and because of minimal processing steps prior to consumption. we have investigated the potential of hot humid air, i.e., aerated steam, to treat alfalfa and mung bean seeds which have been artificially contaminated with escherichia coli o157:h7, salmonella enterica subsp. enterica serovar weltevreden, and listeria monocytogenes scott a. in additio ...201323709507
internalisation potential of escherichia coli o157:h7, listeria monocytogenes, salmonella enterica subsp. enterica serovar typhimurium and staphylococcus aureus in lettuce seedlings and mature plants.the internalisation potential of listeria monocytogenes, staphylococcus aureus, escherichia coli o157:h7 and salmonella enterica subsp. enterica serovar typhimurium in lettuce was evaluated using seedlings grown in vermiculite in seedling trays as well as hydroponically grown lettuce. sterile distilled water was spiked with one of the four human pathogenic bacteria (10(5) cfu/ml) and used to irrigate the plants. the potential for pathogen internalisation was investigated over time using light mi ...201323708570
the feoc protein leads to high cellular levels of the fe(ii) transporter feob by preventing ftsh protease regulation of feob in salmonella enterica.in the gammaproteobacteria, the feoa, feob, and feoc proteins constitute the feo system, which mediates ferrous iron [fe(ii)] import. of these feo proteins, feob is an inner membrane fe(ii) transporter that is aided by the small protein feoa. however, the role of another small protein, feoc, has remained unknown. here we report that the feoc protein is necessary for feob protein-mediated fe(ii) uptake in salmonella experiencing low levels of oxygen and iron. the feoc protein was found to directl ...201323708131
characterisation of plasmids implicated in the mobilisation of extended-spectrum and ampc β-lactamase genes in clinical salmonella enterica isolates and temporal stability of the resistance genotype.plasmids implicated in the mobilisation of β-lactamase genes in extended-spectrum β-lactamase (esbl)- and ampc-producing salmonella enterica isolates recovered from three spanish hospitals were characterised. the temporal stability of these plasmids and of the resistance phenotype without antimicrobial pressure was also assessed in the laboratory setting. the resistance determinants and their genetic environments were characterised by pcr sequencing, and their genomic location was analysed by s1 ...201323706977
dissemination of clonal salmonella enterica serovar typhimurium isolates causing salmonellosis in mauritius.salmonella enterica serotype typhimurium is one of the leading causes of salmonellosis in mauritius, where it has also been associated with outbreaks of foodborne illness. however, little is known about its molecular epidemiology in the country. this study was therefore undertaken to investigate the clonality and source of salmonella typhimurium in mauritius by studying human, food, and poultry isolates by pulsed-field gel electrophoresis (pfge) and antibiotic minimum inhibitory concentration de ...201323705985
igg subclass antibodies to human and bacterial hsp60 are not associated with disease activity and progression over time in axial spondyloarthritis.spondyloarthritis (spa), an interrelated group of rheumatic diseases, has been suggested to be triggered by bacterial infections prior to the development of an autoimmune response that causes inflammation of the spinal and peripheral joints. because human heat shock protein 60 (hsp60), recently renamed hspd1, and bacterial hsp60 are highly homologous, immunological cross-reactivity has been proposed as a mechanism of disease initiation. however, previous investigations of the humoral immune resp ...201323705835
extracellular dna-induced antimicrobial peptide resistance in salmonella enterica serovar typhimurium.the salmonella enterica serovar typhimurium phopq two component system (tcs) is activated by low mg2+ levels, low ph and by antimicrobial peptides (ap). under mg2+ limitation, the phopq system induces pmrd expression, which post-translationally activates the pmrab tcs. phopq and pmrab control many genes required for intracellular survival and pathogenesis. these include the polymyxin resistance (pmr) operon, which is required for aminoarabinose modification of lps and protecting the outer membra ...201323705831
choice of bacterial growth medium alters the transcriptome and phenotype of salmonella enterica serovar typhimurium.the type of bacterial culture medium is an important consideration during design of any experimental protocol. the aim of this study was to understand the impact of medium choice on bacterial gene expression and physiology by comparing the transcriptome of salmonella enterica sl1344 after growth in the widely used lb broth or the rationally designed mops minimal medium. transcriptomics showed that after growth in mops minimal media, compared to lb, there was increased expression of 42 genes invo ...201323704954
genome sequence of salmonella enterica serotype tennessee strain cdc07-0191, implicated in the 2006-2007 multistate food-borne outbreak linked to peanut butter in the united states.salmonella enterica serotype tennessee strain cdc07-0191 was isolated from the 2006-2007 multistate food-borne outbreak linked to peanut butter in the united states. here we report a high-quality draft assembly of the genome sequence of this strain, derived from a patient. this is the first reported high-quality draft genome sequence for s. enterica serotype tennessee, which will enable in-depth studies of its transmission and virulence.201323704182
antimicrobial susceptibility of salmonella enterica serovars in a tertiary care hospital in southern india.salmonella enterica serovars typhi and paratyphi are predominantly known to cause enteric fever. multidrug resistance in s. tphi and s. paratyphi has emerged as a cause of concern. this study was done to evaluate status in antimicrobial susceptibility patterns of salmonella enterica serovar typhi (s. typhi) and s. paratyphi obtained from blood culture in a tertiary care hospital in south india.201323703350
efficacy of integrated treatment of uv light and low-dose gamma irradiation on inactivation of escherichia coli o157:h7 and salmonella enterica on grape tomatoes.the study evaluated the efficacy of integrated ultraviolet-c light (uvc) and low-dose gamma irradiation treatments to inactivate mixed strains of escherichia coli o157:h7 and salmonella enterica on inoculated whole grape tomatoes. a mixed bacterial cocktail composed of a 3 strain mixture of e. coli o157:h7 (c9490, e02128, and f00475) and a 3 serotype mixture of s. enterica (s. montevideo g4639, s. newport h1275, and s. stanley h0558) was used based on their association with produce-related outbr ...201323701667
molecular characterization of salmonella enterica serovar typhimurium isolated from human, food, and animal sources in malaysia.salmonella typhimurium is an important nontyphoidal salmonella serovar associated with foodborne diseases in many parts of the world. this organism is the major causative agent of nontyphoidal salmonellosis in malaysia. we aimed to investigate the genetic profiles of the strains isolated from clinical, zoonotic, and dietary sources in malaysia using multilocus variable number tandem repeat analysis (mlva) and pulsed-field gel electrophoresis (pfge). by focusing on the 5 common variable number ta ...201323698477
genomic analysis of salmonella enterica serovar typhimurium definitive phage type 104. 201323697578
expression, purification, crystallization and preliminary x-ray diffraction analysis of a core fragment of flgg, a bacterial flagellar rod protein.flgg is a bacterial flagellar rod protein and constructs the distal rod connecting to the hook. flgg of salmonella enterica serovar typhimurium is a 260-amino-acid protein composed of a folded core region and n- and c-terminal regions that are unfolded in solution. a core fragment of flgg (flgg47-227) was expressed, purified and crystallized. crystals of native and semet-labelled flgg47-227 were obtained by the sitting-drop vapour-diffusion technique with peg mme 2000 as precipitant. the native ...201323695574
ß-lactamases in salmonella enterica isolated in australia.understanding the antibiotic susceptibility of salmonella enterica is important both from a clinical treatment and a public health perspective. the emergence of extended spectrum ß-lactamases (esßls) and ampc ß-lactamases in s. enterica is important, as this will limit treatment options and could provide a strain with a significant selective advantage. the aim of the study was to screen isolates of s. enterica, including isolates that had previously shown antibiotic resistance, to gauge the exte ...201323692158
the type vi secretion system encoded in spi-6 plays a role in gastrointestinal colonization and systemic spread of salmonella enterica serovar typhimurium in the chicken.the role of the salmonella pathogenicity islands (spis) in pathogenesis of salmonella enterica typhimurium infection in the chicken is poorly studied, while many studies have been completed in murine models. the type vi secretion system (t6ss) is a recently described protein secretion system in gram-negative bacteria. the genus salmonella contains five phylogenetically distinct t6ss encoded in differentially distributed genomic islands. s. typhimurium harbors a t6ss encoded in spi-6 (t6ssspi-6), ...201323691117
the lipopolysaccharide modification regulator pmra limits salmonella virulence by repressing the type three-secretion system spi/ssa.the regulatory protein pmra controls expression of lipopolysaccharide (lps) modification genes in salmonella enterica serovar typhimurium, the etiologic agent of human gastroenteritis and murine typhoid fever. pmra-dependent lps modifications confer resistance to serum, fe(3+), and several antimicrobial peptides, suggesting that the pmra gene is required for salmonella virulence. we now report that, surprisingly, a pmra null mutant is actually hypervirulent when inoculated i.p. into c3h/hen mice ...201323690578
malaria-associated l-arginine deficiency induces mast cell-associated disruption to intestinal barrier defenses against nontyphoidal salmonella bacteremia.coinfection with malaria and nontyphoidal salmonella serotypes (nts) can cause life-threatening bacteremia in humans. coinfection with malaria is a recognized risk factor for invasive nts, suggesting that malaria impairs intestinal barrier function. here, we investigated mechanisms and strategies for prevention of coinfection pathology in a mouse model. our findings reveal that malarial-parasite-infected mice, like humans, develop l-arginine deficiency, which is associated with intestinal mastoc ...201323690397
chicken innate immune response to oral infection with salmonella enterica serovar enteritidis.the characterization of the immune response of chickens to salmonella infection is usually limited to the quantification of expression of genes coding for cytokines, chemokines or antimicrobial peptides. however, processes occurring in the cecum of infected chickens are likely to be much more diverse. in this study we have therefore characterized the transcriptome and proteome in the chicken cecum after infection with salmonella enteritidis. using a combination of 454 pyrosequencing, protein mas ...201323687968
distribution of extended-spectrum cephalosporin resistance determinants in salmonella enterica and escherichia coli isolated from broilers in southern japan.this study was conducted to investigate the distribution and diversity of extended-spectrum cephalosporin (esc) resistance determinants in salmonella enterica and escherichia coli obtained from the same cecal samples and to provide evidence of transmission of the resistance determinants among these bacteria in broiler farms in southern japan. salmonella enterica and e. coli were characterized by serotyping and multilocus sequence typing, respectively. an antimicrobial susceptibility test, plasmi ...201323687161
the use of factorial design, image analysis, and an efficiency calculation for multiplex pcr optimization.the quality of multiplex polymerase chain reaction (pcr) assays depends on several factors. therefore, it is important to establish the optimal conditions to achieve efficient amplification. the objective of this study was to implement a 5 × 4 factorial design combined with image analysis using agarose gels and an efficiency calculation to optimize a multiplex pcr assays for the detection of salmonella enterica serovar typhimurium.201323686781
salmonella enterica mtan at 1.36 å resolution: a structure-based design of tailored transition state analogs.accumulation of 5'-methylthioadenosine (mta) and s-adenosylhomocysteine (sah) in bacteria disrupts the s-adenosylmethionine pool to alter biological methylations, synthesis of polyamines, and production of quorum-sensing molecules. bacterial metabolism of mta and sah depends on mta/sah nucleosidase (mtan), an enzyme not present in humans and a target for quorum sensing because mtan activity is essential for synthesis of autoinducer-2 molecules. crystals of salmonella enterica mtan with product a ...201323685211
spi1 defective mutants of salmonella enterica induce cross-protective immunity in chickens against challenge with serovars typhimurium and enteritidis.in this study we were interested in the serovar cross-protection potential of salmonella pathogenicity island 1 (spi1) attenuated vaccine strains of salmonella enterica serovars enteritidis and typhimurium and immune response of vaccinated and naive chickens to salmonella infection. the immune response was characterized by real time pcr quantifying transcripts of interleukins il1β, il17, il22, interferon gamma (ifnγ), inducible no synthase (inos), immunoglobulins igm, iga, igy and ig light chain ...201323684831
salmonella enterica typhimurium infection causes metabolic changes in chicken muscle involving ampk, fatty acid and insulin/mtor signaling.salmonella enterica serovar typhimurium (salmonella typhimurium) infection of chickens that are more than a few days old results in asymptomatic cecal colonization with persistent shedding of bacteria. we hypothesized that while the bacterium colonizes and persists locally in the cecum it has systemic effects, including changes to metabolic pathways of skeletal muscle, influencing the physiology of the avian host. using species-specific peptide arrays to perform kinome analysis on metabolic sign ...201323682635
survey of enterobacteriaceae contamination of table eggs collected from layer flocks in australia.in the present study, eggs from commercial caged layer flocks at different stages of lay in australia were collected. enterobacteriaceae populations from eggshell surface and eggshell pore were enumerated and these populations characterized using api® rapid 20e strips. the eggshell surface, eggshell pore and egg internal content samples were also processed for the isolation of salmonella and these isolates were tested for the presence or absence of several virulence genes (prgh, sopb, spic, orfl ...201323680799
surveillance of salmonella enteritidis in layer houses: a retrospective comparison of the food and drug administration's egg safety rule (2010-2011) and the california egg quality assurance program (2007-2011).between july 2007 and december 2011, 2660 environmental drag swab samples were collected in total from california layer flocks on behalf of the california egg quality assurance program (ceqap), the egg safety rule (21 cfr parts 16 and 118) of the food and drug administration (fda), or both. the samples were processed by the california animal health and food safety lab, and positive or negative results for salmonella enterica serovar enteritidis (se) were recorded. this study retrospectively comp ...201323678729
safety and efficacy of a metabolic drift live attenuated salmonella gallinarum vaccine against fowl typhoid.fowl typhoid (ft), a systemic disease that results in septicemia in poultry, is caused by salmonella enterica serovar gallinarum biovar gallinarum (sg). mortality and morbidity rates from ft can reach up to 80%. attenuated live salmonella vaccine candidates have received considerable attention because they confer solid immunity, and they can produce systemic and mucosal immunity in the gut when administered orally. in the present study, five metabolic drift (md) mutants with a single-(designated ...201323678726
subtyping of salmonella enterica serovar newport outbreak isolates by crispr-mvlst and determination of the relationship between crispr-mvlst and pfge results.salmonella enterica subsp. enterica serovar newport (s. newport) is the third most prevalent cause of food-borne salmonellosis. rapid, efficient, and accurate methods for identification are required to track specific strains of s. newport during outbreaks. by exploiting the hypervariable nature of virulence genes and clustered regularly interspaced short palindromic repeats (crisprs), we previously developed a sequence-based subtyping approach, designated crispr-multi-virulence-locus sequence ty ...201323678062
clpp deletion causes attenuation of salmonella typhimurium virulence through mis-regulation of rpos and indirect control of csra and the spi genes.salmonella enterica serovar typhimurium requires the type iii secretion system encoded by salmonella pathogenicity island 1 (spi1) and controlled by the master regulator, hila, to penetrate the intestinal epithelium. numerous regulators affect virulence through influence on this system, including the proteolytic component clpp, the stationary phase regulator rpos and the carbon-storage regulator csra. however, the mechanism behind the clpp regulation is not fully understood. to elucidate this we ...201323676436
presence of β-lactamases in extended-spectrum-cephalosporin-resistant salmonella enterica of 30 different serovars in germany 2005-11.between 20 000 and 35 000 cases of salmonellosis are detected annually in germany, but only a few salmonella are resistant to third-generation cephalosporins. the german national reference centre for salmonella and other enterics obtained 150 salmonella enterica isolates from human infections between 2005 and 2011. in the present study we identified the β-lactamase genes causing resistance to third-generation cephalosporins in these isolates.201323674765
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