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withdrawn: azithromycin for treating uncomplicated typhoid and paratyphoid fever (enteric fever).review status: current question - no update intended. azithromycin treatments are included in the review: fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever). (thaver d, zaidi akm, critchley ja, azmatullah a, madni sa, bhutta za. fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever). cochrane database of systematic reviews 2008, issue 4. art. no.: cd004530. doi: 10.1002/14651858.cd004530.pub3.)   this latter review is being updated, and will be publi ...201121975751
effects of residual antibiotics in groundwater on salmonella typhimurium: changes in antibiotic resistance, in vivo and in vitro pathogenicity.an outbreak-causing strain of salmonella enterica serovar typhimurium was exposed to groundwater with residual antibiotics for up to four weeks. representative concentrations (0.05, 1, and 100 μg l(-1)) of amoxicillin, tetracycline, and a mixture of several other antibiotics (1 μg l(-1) each) were spiked into artificially prepared groundwater (agw). antibiotic susceptibility analysis and the virulence response of stressed salmonella were determined on a weekly basis by using human epithelial cel ...201122051852
tlr5-dependent immunogenicity of a recombinant fusion protein containing an immunodominant epitope of malarial circumsporozoite protein and the flic flagellin of salmonella typhimurium.recently, we described the improved immunogenicity of new malaria vaccine candidates based on the expression of fusion proteins containing immunodominant epitopes of merozoites and salmonella enterica serovar typhimurium flagellin (flic) protein as an innate immune agonist. here, we tested whether a similar strategy, based on an immunodominant b-cell epitope from malaria sporozoites, could also generate immunogenic fusion polypeptides. a recombinant his6-tagged flic protein containing the c-term ...201121881771
Lrp acts as both a positive and negative regulator for type 1 fimbriae production in Salmonella enterica serovar Typhimurium.Leucine-responsive regulatory protein (Lrp) is known to be an indirect activator of type 1 fimbriae synthesis in Salmonella enterica serovar Typhimurium via direct regulation of FimZ, a direct positive regulator for type 1 fimbriae production. Using RT-PCR, we have shown previously that fimA transcription is dramatically impaired in both lrp-deletion (?lrp) and constitutive-lrp expression (lrp(C)) mutant strains. In this work, we used chromosomal P(fimA)-lacZ fusions and yeast agglutination assa ...201122046399
BT cationic peptides: Small peptides that modulate innate immune responses of chicken heterophils and monocytes.Neonatal poultry exhibit a transient susceptibility to infectious diseases during the first week of life that stems from inefficient host defense mechanisms. Yet, the initial host immune response to pathogens is a critical determinant of disease resistance and susceptibility. With this context in mind, novel ways to stimulate or modulate the hosts' natural immune response is emerging as an important area of interest for food animal producers including the poultry industry. Specifically, we have ...201122129785
inhibition of growth of highly resistant bacterial and fungal pathogens by a natural product.the continuous escalation of resistant bacteria against a wide range of antibiotics necessitates discovering novel unconventional sources of antibiotics. b. oleracea l (red cabbage) is health-promoting food with proven anticancer and anti-inflammatory activities. however, it has not been researched adequately for its antimicrobial activity on potential resistant pathogens. the methanol crude extract of b. oleracea l. was investigated for a possible anti-microbial activity. the screening method w ...201121915230
pulsed-field gel electrophoresis supports the presence of host-adapted salmonella enterica subsp. enterica serovar typhimurium strains in the british garden bird population.salmonellosis is a frequently diagnosed infectious disease of passerine birds in garden habitats within great britain with potential implications for human and domestic animal health. postmortem examinations were performed on 1,477 garden bird carcasses of circa 50 species from england and wales, 1999 to 2007 inclusive. salmonellosis was confirmed in 263 adult birds of 10 passerine species in this 11-year longitudinal study. a subset of 124 fully biotyped salmonella enterica subsp. enterica sero ...201121948838
isolation and characterization of bacteriophages of salmonella enterica serovar pullorum.in this study, 2 bacteriophages of salmonella pullorum were isolated using an enrichment protocol and the double agar layer method. they were named pspu-95 and pspu-4-116, respectively, against clinical isolates of salmonella pullorum spu-95 and spu-116. the host ranges of the 2 bacteriophages were determined by performing spot tests with 20 bacteria strains. both bacteriophages had wide host ranges. bacteriophage pspu-95 had a lytic effect on 17 of the 20 isolates (85%), and pspu-4-116 produced ...201121934022
Acanthamoeba polyphaga, a potential environmental vector for the transmission of food-borne and opportunistic pathogens.The endosymbiotic relationship could represent for many bacteria an important condition favouring their spread in the environment and in foods. For this purpose we studied the behaviour of some food-borne and opportunistic pathogens (Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, Salmonella enterica serovar Enteritidis, Aeromonas hydrophila, Yersinia enterocolitica) when internalized in Acanthamoeba polyphaga. Our results confirm the capability of the bacteria tested to gr ...201121953544
Three novel Anas platyrhynchos avian ß-defensins, upregulated by duck hepatitis virus, with antibacterial and antiviral activities.Three novel Anas platyrhynchos avian ß-defensins (Apl_AvBDs), Apl_AvBD4, 7 and 12, were identified successfully and characterized in tissues from Peking ducks in the present study. The cDNA fragment of Apl_AvBD4 contained 171 bp, and encoded 56 amino acids. The complete nucleotide sequences of Apl_AvBD7 and 12 contained 204 bp and 198 bp open reading frames, which encoded 67 and 65 amino acids, respectively. Both recombinant and synthetic forms of the three Apl_AvBDs showed antibacterial activit ...201121856003
Epidemiological characteristics and molecular typing of Salmonella enterica serovar Typhi during a waterborne outbreak in Eastern Anatolia.In this study, we aimed to study the molecular and epidemiological characteristics of Salmonella enterica serovar Typhi (S. Typhi) outbreak in Eastern Anatolia. Six hundred and thirty-seven patients from the same county with clinical diagnosis of typhoid fever were investigated with conventional methods from stool, urine and blood specimens. Antibiotic susceptibility tests and identifications were performed for positive specimens. Clonal relationships between the isolates were investigated using ...201121929877
phosphoproteomic analysis of salmonella-infected cells identifies key kinase regulators and sopb-dependent host phosphorylation events.salmonella enterica is a bacterial pathogen that causes gastroenteritis and typhoid fever. virulence is achieved by two type iii secretion systems that translocate effector proteins into host cells, where they mimic or block host protein function. effectors translocated into host cells by the first type iii secretion system facilitate invasion and stimulate intracellular signaling cascades leading to inflammation. here, we performed global temporal analysis of host signaling events induced durin ...201121934108
MLVA polymorphism of Salmonella enterica subspecies isolated from humans, animals, and food in Cambodia.ABSTRACT:201121861934
Imaging and analysis of Pseudomonas aeruginosa swarming and rhamnolipid production.Many bacteria spread over surfaces by "swarming" in groups. A problem for scientists who study swarming is the acquisition of statistically significant data that distinguish two observations or detail the temporal patterns and two-dimensional heterogeneities that occur. It is currently difficult to quantify differences between observed swarm phenotypes. Here, we present a method for acquisition of temporal surface motility data using time-lapse fluorescence and bioluminescence imaging. We specif ...201121984238
Control of Salmonella enterica Typhimurium in chicken breast meat by irradiation combined with modified atmosphere packaging.Salmonella is one of the leading causes of human foodborne illnesses originating from meat and poultry products. Cross-contamination of Salmonella from raw to cooked products continues to be problematic in the food industry. Therefore, new intervention strategies are needed for meat and poultry products. Vacuum or modified atmosphere packaging (MAP) are common packaging techniques used to extend the shelf life of meat products. Irradiation has been well established as an antibacterial treatment ...201122054182
Application of a bacteriophage cocktail to reduce Salmonella Typhimurium U288 contamination on pig skin.Multidrug-resistant Salmonella Typhimurium U288 is a significant pathogen of pigs, accounting for over half of all outbreaks on UK pig production premises. The potential of this serovar, and other salmonellae, to enter the food chain during the slaughtering process requires that efforts be made to reduce the prevalence of these bacteria at both the pre- and post-harvest stages of production. A bacteriophage cocktail (PC1) capable of lysing various Salmonella enterica serovars was designed using ...201121899907
Modification of the BAX Salmonella test kit to include a hot start functionality (modification of AOAC Official Method 2003.09).In 2010, the BAX System PCR assay for Salmonella was modified to include a hot start functionality designed to keep the reaction enzyme inactive until PCR begins. To validate the assay's Official Methods of Analysis status to include this procedure modification, an evaluation was conducted on four food types that were simultaneously analyzed with the BAX System and either the U.S. Food and Drug Administration's Bacteriological Analytical Manual or the U.S. Department of Agriculture-Food Safety a ...201122165013
genetic characterization of the mechanisms of resistance to amoxicillin/clavulanate and third-generation cephalosporins in salmonella enterica from three spanish hospitals.the mechanisms of antimicrobial resistance were characterized in 90 salmonella enterica isolates either resistant or with intermediate resistance to amoxicillin/clavulanate (amc(r/i)) or resistant to third-generation cephalosporins (c3g(r)). these isolates were recovered in three spanish hospitals during 2007-2009. the c3g(r) phenotype was expressed by three isolates that carried the following extended-spectrum β-lactamase genes: phage-associated bla(ctx m-10) in s. virchow, bla(ctx-m-14a) surro ...201122101415
Application of a 16S rRNA PCR/HRMA Assay for Rapid Detection of Salmonella Bacteremia: A Case Report.Current culture and phenotypic protocols for diagnosing Salmonella infections can be time consuming. Here, we describe the application of a 16S rRNA PCR coupled to high resolution melt analysis for species and serotype identification in six hours of blood sample collection from a patient with Salmonella serotype Enteritidis bacteremia.201122205823
comparison of two possible routes of pathogen contamination of spinach leaves in a hydroponic cultivation system.the route of pathogen contamination (from roots versus from leaves) of spinach leaves was investigated with a hydroponic cultivation system. three major bacterial pathogens, escherichia coli o157:h7, salmonella, and listeria monocytogenes, were inoculated into the hydroponic solution, in which the spinach was grown to give concentrations of 10⁶ and 10³ cfu/ml. in parallel, the pathogens were inoculated onto the growing leaf surface by pipetting, to give concentrations of 10⁶ and 10³ cfu per leaf ...201121902924
Crystallization and preliminary crystallographic analysis of an Ig-domain-encompassing fragment of the giant adhesion protein SiiE from Salmonella enterica.Salmonella infections can be life-threatening. SiiE is a giant adhesion molecule of 5559 amino acids that is encoded in Salmonella pathogenicity island 4 (SPI4) and that promotes the initial contact between the pathogen and polarized epithelial cells in the intestine of the host. Starting from an engineered deletion version of SiiE (mini-SiiE; 97 kDa), limited proteolysis was used to reproducibly generate a 30 kDa fragment that readily crystallized. Mass spectrometry hints that this fragment spa ...201122102234
two efficient methods for the conjugation of smooth-form lipopolysaccharides with probes bearing hydrazine or amino groups. i. lps activation with cyanogen bromide.this chapter presents a conjugation method for coupling probes bearing hydrazine or primary amino groups to a smooth(s)-form lipopolysaccharide (lps). lps is modified by the activation of the hydroxyl groups present in its o-antigen moiety with cyanogen bromide in aqueous acetone. the method yields conjugates with good labeling ratios, preserving the endotoxic activity of the lipid a moiety. conjugation of smooth-form lps from salmonella enterica sv. minnesota with dansyl hydrazine and horseradi ...201121567325
two efficient methods for the conjugation of smooth-form lipopolysaccharides with probes bearing hydrazine or amino groups. ii. lps activation with a cyanopyridinium agent.this chapter presents a conjugation method for coupling probes bearing hydrazine or primary amino groups to a lipopolysaccharide (lps). lps is modified by the activation of the hydroxyl groups present in its o-antigen moiety with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (cdap). the method yields conjugates with good labeling ratios, preserving the endotoxic activity of the lipid a moiety. conjugation of smooth-form lps from salmonella enterica sv. minnesota with dansyl hydrazine and h ...201121567326
Characterization of Salmonella occurring at high prevalence in a population of the land iguana Conolophus subcristatus in Galápagos Islands, Ecuador.The aim of the study was to elucidate the association between the zoonotic pathogen Salmonella and a population of land iguana, Colonophus subcristatus, endemic to Galápagos Islands in Ecuador. We assessed the presence of Salmonella subspecies and serovars and estimated the prevalence of the pathogen in that population. Additionally, we investigated the genetic relatedness among isolates and serovars utilising pulsed field gel electrophoresis (PFGE) on XbaI-digested DNA and determined the antimi ...201121853080
[Development of modified molecular beacon based real-time PCR assay for the rapid detection of Salmonella choleraesuis and Salmonella paratyphi C].To develop real-time PCR assay based on modified molecular beacon for simultaneous detection of S. choleraesuis and S. paratyphi C. The established method was applied to the rapid detection of S. choleraesuis in food and stool samples of food poisoning, and then was applied to the identification of Salmonella C.201121861361
WFDC2 is differentially expressed in the mammary gland of the tammar wallaby and provides immune protection to the mammary gland and the developing pouch young.WAP four disulfide core domain 2 (WFDC2) is a four disulfide core (4-DSC) protein secreted in the milk of the tammar wallaby. It is comprised of two 4-DSC domains assigned domain III at the NH2-terminal end and domain II at the COOH-terminal end. The WFDC2 gene was expressed only during pregnancy, early lactation, towards the end of lactation and involution. The WFDC2 protein showed antibacterial activity against Staphylococcus aureus, Salmonella enterica and Pseudomonas aeruginosa and this acti ...201122024352
multidrug-resistant salmonella enterica. 201122035610
Small intestinal CD8+TCR?d+ intraepithelial lymphocytes (iIELs) are involved in bacterial clearance during Salmonella typhimurium infection.The intestinal immune system is crucial for the maintenance of mucosal homeostasis and has evolved under the dual pressure of protecting the host from pathogenic infection and co-existence with the dense and diverse commensal organisms in the lumen. Intestinal intraepithelial lymphocytes (iIELs) are the first element of the host T cell compartment available to respond to oral infection by pathogens. This study demonstrated that oral infection by Salmonella typhimurium (S. typhimurium) promoted t ...201122144492
A Salmonella Virulence Factor Activates the NOD1/NOD2 Signaling Pathway.ABSTRACT The invasion-associated type III secretion system (T3SS-1) of Salmonella enterica serotype Typhimurium (S. Typhimurium) activates the transcription factor NF-?B in tissue culture cells and induces inflammatory responses in animal models through unknown mechanisms. Here we show that bacterial delivery or ectopic expression of SipA, a T3SS-1-translocated protein, led to the activation of the NOD1/NOD2 signaling pathway and consequent RIP2-mediated induction of NF-?B-dependent inflammatory ...201122186610
The MgtR regulatory peptide negatively controls expression of the MgtA Mg(2+) transporter in Salmonella enterica serovar Typhimurium.MgtR is a 30 amino acid peptide that is encoded from the mgtCBR operon. This peptide has recently been demonstrated to interact with the MgtC virulence protein and lead to MgtC degradation. In the present study, we reveal that the MgtA Mg(2+) transporter is another protein under the direct control of the MgtR peptide. Salmonella expresses the MgtA transporter only in Mg(2+) depleted conditions. We determined that the MgtR peptide limits levels of the MgtA protein at low Mg(2+) concentrations. Mg ...201122155249
defining treatment conditions for pulsed electric field pasteurization of apple juice.the influence of temperature and the presence of n(α)-lauroyl ethylester (ethyl lauroyl arginate, lae) on the inactivation caused by continuous pulsed electric field treatments (pef) in escherichia coli o157:h7 suspended in apple juice have been investigated to define treatment conditions applicable at industrial scale that promote an equivalent safety level when compared with thermal processing. in the range of experimental conditions investigated (outlet temperature: 20-40 °c, electric field s ...201121880388
Survival of host-associated Bacteroidales cells and their relationship with Enterococcus spp., Campylobacter jejuni, Salmonella Typhimurium and Adenovirus in freshwater microcosms as measured by PMA-qPCR.The ideal host-associated genetic fecal marker would be capable of predicting the presence of specific pathogens of concern. Flow-through freshwater microcosms containing mixed feces and inocula of the pathogens Campylobacter jejuni, Salmonella Typhimurium and Adenovirus were placed at ambient temperature in the presence and absence of diurnal sunlight. The total Enterococcus DNA increased during the early periods (23 h) under sunlight exposure, even though cultivable Enterococcus and DNA in int ...201122139002
The Fur regulon in anaerobically grown Salmonella enterica sv. Typhimurium: identification of new Fur targets.ABSTRACT:201122017966
Survival characteristics of Salmonella enterica serovar Newport in the dairy farm environment.Multi-drug resistant (MDR) Salmonella enterica serovar Newport (S. Newport) has established a reservoir in dairy cattle. Infected herds suffer significant mortality in both adult and young animals, posing a considerable economic loss to producers. Land application of manure from infected animals may further spread the pathogen into the agroecosystem, causing public health concerns. Previous work by our group demonstrated that the organism persisted in manure and manured soil for 6 to 10 mo under ...201121943774
Salmonella biofilm formation on Aspergillus niger involves cellulose--chitin interactions.Salmonella cycles between host and nonhost environments, where it can become an active member of complex microbial communities. The role of fungi in the environmental adaptation of enteric pathogens remains relatively unexplored. We have discovered that S. enterica Typhimurium rapidly attaches to and forms biofilms on the hyphae of the common fungus, Aspergillus niger. Several Salmonella enterica serovars displayed a similar interaction, whereas other bacterial species were unable to bind to the ...201122003399
Reduction of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes with electrolyzed oxidizing water on inoculated hass avocados (Persea americana var. Hass).This study was intended to evaluate the bactericidal effect of electrolyzed oxidizing water (EOW) and chlorinated water on populations of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes inoculated on avocados (Persea americana var. Hass). In the first experiment, inoculated avocados were treated with a water wash applied by spraying tap water containing 1 mg/liter free chlorine for 15 s (WW); WW treatment and then spraying sodium hypochlorite in water containing 75 mg/l ...201121902927
genotyping of salmonella enterica serovar typhi strains isolated from 1959 to 2006 in china and analysis of genetic diversity by genomic microarray.aim. to determine the genotype of salmonella enterica serovar typhi (s. typhi) strains in china and analyze their genetic diversity. methods. we collected s. typhi strains from 1959 to 2006 in five highly endemic chinese provinces and chose 40 representative strains. multilocus sequence typing was used to determine the genotypes or sequence types (st) and microarray-based comparative genomic hybridization (m-cgh) to investigate the differences in gene content among these strains. results. forty ...201122180267
single nucleotide polymorphisms that differentiate two subpopulations of salmonella enteritidis within phage type.abstract:201121942987
salmonella enterica serotype typhimurium usurps the scaffold protein iqgap1 to manipulate rac1 and mapk signalling.salmonella enterica serotype typhimurium invades eukaryotic cells by re-arranging the host-cell cytoskeleton. however, the precise mechanisms by which salmonella induces cytoskeletal changes remain undefined. iqgap1 (iq motif-containing gtpase-activating protein 1) is a scaffold protein that binds multiple proteins including actin, the rho gtpases rac1 and cdc42 (cell division cycle 42), and components of the mapk (mitogen-activated protein kinase) pathway. we have shown previously that optimal ...201121851337
acra dependency of the acrd efflux pump in salmonella enterica serovar typhimurium.multidrug efflux pumps belonging to the resistance-nodulation cell division (rnd) family have major roles in the intrinsic and elevated resistance of gram-negative bacteria to a wide range of compounds. rnd efflux pumps require two other proteins to function: a membrane fusion protein (mfp) and an outer membrane protein. a recent study demonstrated that salmonella enterica serovar typhimurium has five rnd efflux systems: acrab, acrd, acref, mdtabc and mdsabc. most rnd efflux system genes also co ...201121505470
comparative analysis of the bacterial flora of vegetables collected directly from farms and from supermarkets in germany.a total of 1,001 vegetables were collected from 13 farms and 11 supermarkets in bavaria, germany; 722 samples were positive for coliforms (mostly enterobacter cloacae; n = 176). escherichia coli were detected in 34, pseudomonas spp. in 439, salmonella spp. in 1, enterococcus spp. in 682, and listeria spp. in 11 samples. prevalence of all investigated genera tended to be lower in samples collected at the supermarket. however, prevalence of pseudomonas fluorescens was higher in supermarket samples ...201121506036
activation of cryptic aminoglycoside resistance in salmonella enterica.aminoglycoside resistance in bacteria can be acquired by several mechanisms, including drug modification, target alteration, reduced uptake and increased efflux. here we demonstrate that increased resistance to the aminoglycosides streptomycin and spectinomycin in salmonella enterica can be conferred by increased expression of an aminoglycoside adenyl transferase encoded by the cryptic, chromosomally located aada gene. during growth in rich medium the wild-type strain was susceptible but mutatio ...201121507083
biofilm formation by salmonella enterica serovar typhimurium colonizing solid tumours.systemic administration of salmonella enterica serovar typhimurium to tumour bearing mice results in preferential colonization of the tumours and retardation of tumour growth. although the bacteria are able to invade the tumour cells in vitro, in tumours they were never detected intracellularly. ultrastructural analysis of salmonella-colonized tumours revealed that the bacteria had formed biofilms. interestingly, depletion of neutrophilic granulocytes drastically reduced biofilm formation. obvio ...201121507181
national outbreak of salmonella enteritidis phage type 14b in england, september to december 2009: case-control study.we conducted an unmatched retrospective case–control study to investigate an upsurge of non-travel-related sporadic cases of infection with salmonella enterica subsp. enterica serotype enteritidis phage type 14b with antimicrobial resistance to nalidixic acid and partial resistance to ciprofloxacin (s. enteritidis pt 14b nxcp(l)) that was reported in england from 1 september to 31 december 2009. we analysed data from 63 cases and 108 controls to determine whether cases had the same sources of in ...201121507321
structural basis for microcin c7 inactivation by the mcce acetyltransferase.the antibiotic microcin c7 (mcc) acts as a bacteriocide by inhibiting aspartyl trna synthetase, and stalling the protein translation machinery. mcc is synthesized as a heptapeptide-nucleotide conjugate, which is processed by cellular peptidases within target strains to yield the biologically active compound. as unwanted processing of intact mcc can result in self-toxicity, producing strains utilize multiple mechanisms for autoimmunity against processed mcc. we have previously shown that the mcce ...201121507941
effect of the growth environment on the strain variability of salmonella enterica kinetic behavior.intra-species variability of microbial growth kinetic behavior is an event with important implications for food safety research. aiming at the evaluation of the growth variability among salmonella enterica strains as affected by the growth environment, the kinetic behavior of 60 isolates of the pathogen was assessed at 37 °c in tryptone soy broth of different ph values (4.3-7.0) and nacl concentrations (0.5-6.0%). maximum specific growth rate (μ(max)) values corresponding to each strain and grow ...201121511146
purification, amino acid sequence and characterization of the class iia bacteriocin weissellin a, produced by weissella paramesenteroides dx.weissella paramesenteroides dx has been shown to produce a 4450-da class iia bacteriocin, weissellin a, composed of 43 amino acids with the sequence knygngvycnkhkcsvdwatfsaniannsvamagltggnagn. the bacteriocin shares 68% similarity with leucocin c from leuconostoc mesenteroides. computational analyses predict that the bacteriocin is a hydrophobic molecule with a beta-sheet type conformation. weissellin a exhibited various levels of activity against all gram-positive bacteria tested, but was not a ...201121511463
contribution of the phop/q regulon to survival and replication of salmonella enterica serovar typhimurium in macrophages.the ability of serovars of salmonella enterica to cause systemic disease is dependent upon their survival and replication within macrophages. to do this, bacteria must withstand or surmount bacteriostatic and bactericidal responses by the host cell, including the delivery of hydrolytic enzymes from lysosomes to the phagosome. the bacterial two component regulatory system, phop/q, has been implicated in avoidance of phagolysosomal fusion by s. enterica serovar typhimurium in murine macrophages. i ...201121511762
rapid screening of epidemiologically important salmonella enterica subsp. enterica serovars using whole-cell maldi-tof mass spectrometry.currently, 2,610 different salmonella serovars are described according to the white-kauffmann-le minor scheme. they are routinely differentiated by serotyping, which is based on the antigenic variability at lipopolysaccharide moieties (o antigens), flagellar proteins (h1 and h2 antigens), and capsular polysaccharides (vi antigens). the aim of this study was to evaluate the potential of maldi-tof mass spectrometry for rapid screening and identification of epidemiologically important salmonella en ...201121515723
low expression of acrb in the deoxycholate-sensitive strains of salmonella enterica subspecies enterica serovar pullorum.we investigated the mechanism responsible for bile susceptibility in three deoxycholate-sensitive (dcs) strains of salmonella enterica subspecies enterica serovar pullorum isolated in 1958 in japan. of the genes encoding the acrab-tolc efflux system, the expression of acrb mrna was 10-fold lower in the dcs strains than in a deoxycholate-resistant (dcr) strain, whereas those of the acra and tolc genes were two-fold lower. these results suggested that low expression of acrb was strongly correlated ...201121517946
integration of a complex regulatory cascade involving the sira/bara and csr global regulatory systems that controls expression of the salmonella spi-1 and spi-2 virulence regulons through hild.salmonella pathogenicity islands 1 and 2 (spi-1 and spi-2) play key roles in the pathogenesis of salmonella enterica. previously, we showed that when salmonella grows in luria-bertani medium, hild, encoded in spi-1, first induces the expression of hila, located in spi-1, and subsequently of the ssrab operon, located in spi-2. these genes code for hila and the ssra/b two-component system, the positive regulators of the spi-1 and spi-2 regulons respectively. in this study, we demonstrate that csra ...201121518393
outbreak of salmonella braenderup infection originating in boxed lunches in japan in 2008.there have been only 2 reports of a large-scale foodborne outbreak arising from salmonella enterica serotype braenderup infection worldwide. on august 9, 2008, an outbreak originating in boxed lunches occurred in okayama, japan. we conducted a cohort study of 786 people who received boxed lunches from a particular catering company and collected 644 questionnaires (response rate:82%). cases were defined as those presenting with diarrhea (≧4 times in 24h) or fever (≧38℃) between 12 am on august 8 ...201121519363
antibacterial activity of different honeys against pathogenic bacteria.to study the antimicrobial activity of honey, 60 samples of various botanical origin were evaluated for their antimicrobial activities against 16 clinical pathogens and their respective reference strains. the microbiological quality of honeys and the antibiotic susceptibility of the various isolates were also examined. the bioassay applied for determining the antimicrobial effect employs the well-agar diffusion method and the estimation of minimum active dilution which produces a 1mm diameter in ...201121524711
presence and distribution of fungi and bacteria in the reproductive tract of healthy stallions.a saprophytic bacterial flora is present on the penis and the distal part of the urethra of stallions. little is known about the fungal flora of their reproductive tract. as micro organisms play an important role in mares fertility, the aim of the study was to describe the distribution of fungi and bacteria in the normal genital apparatus of stallions. the microbic flora of the reproductive tract of 11 healthy, fertile stallions was evaluated, collecting samples from 5 different locations: ureth ...201121529914
the x-ray structure of the zinc transporter znua from salmonella enterica discloses a unique triad of zinc-coordinating histidines.znua is the soluble component of the high-affinity znuabc zinc transporter belonging to the cluster 9 group of atp-binding cassette-type periplasmic zn- and mn-binding proteins. in gram-negative bacteria, the znuabc system is essential for zinc uptake and homeostasis and is an important determinant of bacterial resistance to the host defense mechanisms. the cluster 9 members share a two (α/β)(4) domain architecture with a long α-helix connecting the two domains. in the zn-specific proteins, the ...201121530543
a discriminant based charge deconvolution analysis pipeline for protein profiling of whole cell extracts using liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry.a discriminant based charge deconvolution analysis pipeline is proposed. the molecular weight determination (mowed) charge deconvolution method was applied directly to the discrimination rules obtained by the fuzzy rule-building expert system (fures) pattern classifier. this approach was demonstrated with synthetic electrospray ionization-mass spectra. identification of the tentative protein biomarkers by bacterial cell extracts of salmonella enterica serovar typhimurium strains a1 and a19 by li ...201121530796
gatifloxacin versus chloramphenicol for uncomplicated enteric fever: an open-label, randomised, controlled trial.we aimed to investigate whether gatifloxacin, a new generation and affordable fluoroquinolone, is better than chloramphenicol for the treatment of uncomplicated enteric fever in children and adults.201121531174
expression and activity of a novel cathelicidin from domestic cats.cathelicidins are small cationic antimicrobial peptides found in many species including primates, mammals, marsupials, birds and even more primitive vertebrates, such as the hagfish. some animals encode multiple cathelicidins in their genome, whereas others have only one. this report identifies and characterizes feline cathelicidin (fecath) as the sole cathelicidin in domestic cats (felis catus). expression of fecath is predominantly found in the bone marrow, with lower levels of expression in t ...201121533281
inappropriate use of d-values for determining biocidal activity of various antimicrobials.the objective of this study was to investigate the application of established d-value calculations to survival curves for various bacteria using the following antimicrobials: acidified sodium chlorite, triclosan, octanoic acid, and sodium hydroxide. d-values can be calculated in 3 ways, a linear regression, an endpoint calculation, or an average of multiple endpoint calculations. the assumption made in calculating a d-value is that the rate of kill follows 1st-order kinetics under specified trea ...201121535698
physical and antibacterial properties of edible films formulated with apple skin polyphenols.fruit and vegetable skins have polyphenolic compounds, terpenes, and phenols with antimicrobial and antioxidant activity. these flavoring plant essential oil components are generally regarded as safe. edible films made from fruits or vegetables containing apple skin polyphenols have the potential to be used commercially to protect food against contamination by pathogenic bacteria. the main objective of this study was to evaluate physical properties as well as antimicrobial activities against lis ...201121535779
modification of buffered peptone water for improved recovery of heat-injured salmonella typhimurium.rapid detection of salmonella in foods is often limited by the high demand for the sensitivity of detection, poor physiological conditions of the target cells, and high concentration of background flora. in this study, the conditions of nonselective enrichment cultivation were modified in order to improve the quantitative detection of heat-injured salmonella in minced meat. the effect of the modifications on the recovery was observed by means of rna-based sandwich hybridization, which was adjust ...201121535838
application of polylactic acid coating with antimicrobials in reduction of escherichia coli o157:h7 and salmonella stanley on apples.survival of escherichia coli o157:h7 and salmonella stanley on apples as affected by application of polylactic acid (pla) coating with antimicrobials was investigated. golden delicious apples were spot inoculated with e. coli o157:h7 or s. stanley and spray coated with pla solutions containing lactic acid (la), disodium ethylenediaminetetraacetic acid (edta), sodium benzoate (sb), potassium sorbate (ps), or their combination (la + edta, sb + la, sb + la + edta). apples without any coating treatm ...201121535842
chronic typhoid infection and the risk of biliary tract cancer and stones in shanghai, china.abstract: previous studies have shown a positive association between chronic typhoid carriage and biliary cancers. we compared serum salmonella enterica serovar typhi antibody titers between biliary tract cancer cases, biliary stone cases without evidence of cancer, and healthy subjects in a large population-based case-control study in shanghai, china.participants included 627 newly diagnosed primary biliary tract cancer patients; 1,037 biliary stone cases (774 gallbladder and 263 bile-duct) and ...201121535882
the antibiotic dehydrophos is converted to a toxic pyruvate analog by peptide bond cleavage in salmonella enterica.the metabolic processing of dehydrophos, a broad-spectrum peptide antibiotic containing an unusual vinyl-phosphonate moiety, was examined using a panel of salmonella enterica mutants deficient in peptide uptake and catabolism. dehydrophos bioactivity is lost in opp, tpp double mutants, demonstrating a requirement for uptake via non-specific oligopeptide permeases. dehydrophos bioactivity is also abolished in a quadruple salmonella mutant lacking the genes encoding peptidases a, b, d, and n, show ...201121537024
[experiences in the epidemiological surveillance of foodborne pathogens by pulsed field gel electrophoresis (pfge) in peru.]foodborne diseases and other enteric infections often occur as outbreaks and cause morbidity and mortality all over the world. in perú, they represent a serious public health problem, and are caused by a great variety of infectious agents. for epidemiological research, a wide array of typification methods are used. one of the most important tools for the molecular subtyping of bacterial pathogens is the pulsed field gel electrophoresis (pfge), which is a highly precise method that allows the dis ...201121537781
a comprehensive study of the contribution of salmonella enterica serovar typhimurium spi2 effectors to bacterial colonization, survival, and replication in typhoid fever, macrophage, and epithelial cell infection models.salmonella enterica serovars are gram-negative bacterial pathogens responsible for human diseases including gastroenteritis and typhoid fever. after ingestion, salmonella cross the intestinal epithelial barrier, where they are phagocytosed by macrophages and dendritic cells, which then enables their spread to systemic sites during cases of typhoid fever. salmonella use two type 3 secretion systems encoded by salmonella pathogenicity islands (spi) 1 and 2 to inject virulence proteins into host ce ...201121540636
active suppression of early immune response in tobacco by the human pathogen salmonella typhimurium.the persistence of enteric pathogens on plants has been studied extensively, mainly due to the potential hazard of human pathogens such as salmonella enterica being able to invade and survive in/on plants. factors involved in the interactions between enteric bacteria and plants have been identified and consequently it was hypothesized that plants may be vectors or alternative hosts for enteric pathogens. to survive, endophytic bacteria have to escape the plant immune systems, which function at d ...201121541320
systemic and mucosal immunity induced by attenuated salmonella enterica serovar typhimurium expressing orf7 of porcine reproductive and respiratory syndrome virus.oral administration of attenuated salmonella vaccine may provide valuable advantages such as low cost, easy preparation, and safety. attenuated salmonella vaccines also serve as carriers of foreign antigens and immunomodulatory cytokines. presently, an attenuated salmonella enterica serovar typhimurium strain was used as a carrier for open reading frame 7 (orf7) protein of porcine reproductive and respiratory syndrome virus (prrsv), a swine pathogen of significant global economic importance. ini ...201121543119
masscode liquid arrays as a tool for multiplexed high-throughput genetic profiling.multiplexed detection assays that analyze a modest number of nucleic acid targets over large sample sets are emerging as the preferred testing approach in such applications as routine pathogen typing, outbreak monitoring, and diagnostics. however, very few dna testing platforms have proven to offer a solution for mid-plexed analysis that is high-throughput, sensitive, and with a low cost per test. in this work, an enhanced genotyping method based on masscode technology was devised and integrated ...201121544191
efficacy of ε-polylysine, lauric arginate, or acidic calcium sulfate applied sequentially for salmonella reduction on membrane filters and chicken carcasses.salmonella contamination continues to be one of the major concerns for the microbiological safety of raw poultry products. application of more than one decontamination agent as a multihurdle intervention to carcasses in a processing line might produce greater reductions than one treatment alone due to different modes of action of individual antimicrobials. in this study, all possible two-way combinations and individual applications of ε-polylysine (epl), lauric arginate (lae), and acidic calcium ...201121549044
prevalence of salmonella enterica, listeria monocytogenes, and escherichia coli virulence factors in bulk tank milk and in-line filters from u.s. dairies.the zoonotic bacteria salmonella enterica, listeria monocytogenes, and escherichia coli are known to infect dairy cows while not always causing clinical signs of disease. these pathogens are sometimes found in raw milk, and human disease outbreaks due to these organisms have been associated with the consumption of raw milk or raw milk products. bulk tank milk (btm) samples (536) and in-line milk filters (519) collected from dairy farms across the united states during the national animal health m ...201121549046
crystal structures of slya, a master virulence regulator of salmonella, in free and dna-bound states.slya is a master virulence regulator that controls the transcription of numerous genes in salmonella enterica. we present here crystal structures of slya by itself and bound to a high-affinity dna operator sequence in the slya gene. slya interacts with dna through direct recognition of a guanine base by r65, as well as interactions between conserved r86 and the minor groove and a large network of non-base-specific contacts to the sugar-phosphate backbone. our structures, together with an unpubli ...201121550983
n-benzyl-3-sulfonamidopyrrolidines are a new class of bacterial dna gyrase inhibitors.this paper characterizes n-benzyl-3-sulfonamidopyrrolidines (gyramides) as dna gyrase inhibitors. gyramide a was previously shown to exhibit antimicrobial activity that suggested it inhibited bacterial cell division. in this study, we conducted target identification studies and identified dna gyrase as the primary target of gyramide a. the gyramide a resistance-determining region in dna gyrase is adjacent to the dna cleavage gate and is a new site for inhibitor design. we studied the antibiotic ...201121552338
secondary renal tubular acidosis in a hereford calf.a 3-month-old hereford heifer calf was presented for lethargy. blood gas analysis and plasma biochemical testing revealed severe metabolic acidosis, azotemia, hyponatremia, hyperchloremia, and normal anion gap. results of a urinalysis were consistent with acute tubular necrosis with inadequate acidification of urine based on the degree of acidemia. salmonella enterica serovar agona was cultured from both urine and feces. the calf was treated with intravenous polyionic fluids, bicarbonate, and an ...201121554363
yqic of salmonella enterica serovar typhimurium is a membrane fusogenic protein required for mice colonization.abstract:201121554724
immune response of chicken gut to natural colonisation by gut microflora and to salmonella enterica serovar enteritidis infection.in commercial poultry production, there is a lack of natural flora providers since chickens are hatched in the clean environment of a hatchery. events occurring soon after hatching are therefore of particular importance and that is why we were interested in the development of the gut microbial community, the immune response to natural microbial colonisation and the response to salmonella enteritidis infection as a function of chicken age. the complexity of chicken gut microbiota gradually increa ...201121555397
protective role of akt2 in salmonella enterica serovar typhimurium-induced gastroenterocolitis.the salmonella effector protein sopb has previously been shown to induce activation of akt and protect epithelial cells from apoptosis in vitro. to characterize the role of akt2 in host defense against salmonella typhimurium infection, wild-type (wt) mice and mice lacking akt2 (akt2 ko) were infected using a salmonella acute gastroenteritis model. infected akt2 ko mice showed a more pronounced morbidity and mortality associated with higher bacterial loads in the intestines, and elevated levels o ...201121555401
adhesive mechanisms of salmonella enterica.salmonella enterica is an invasive, facultative intracellular pathogen of animal and man with the ability to colonize various niches in diverse host organisms. the pathogenesis of infections by s. enterica requires adhesion to various host cell surfaces, and a large number of adhesive structures can be found. depending on the serotype of s. enterica, gene clusters for more than 10 different fimbrial adhesins were identified, with type i fimbriae such as fim, lpf (long polar fimbriae), tafi (thin ...201121557055
computational investigation of the enzymatic mechanisms of phosphothreonine lyase.spvc, a virulence effector injected through type iii secretion system by some salmonella serovars, belongs to the newly discovered enzyme family, phosphothreonine lyase. previous experimental studies have demonstrated that spvc irreversibly inactivates mitogen-activated protein kinases by removing the phosphate group from phosphothreonine-containing substrate through a β-elimination mechanism, and results in a β-methyldehydroalanine product. interestingly, further biochemical investigations also ...201121558045
m153r mutation in a ph-sensitive green fluorescent protein stabilizes its fusion proteins.green fluorescent protein (gfp) and its fusion proteins have been used extensively to monitor and analyze a wide range of biological processes. however, proteolytic cleavage often removes gfp from its fusion proteins, not only causing a poor signal-to-noise ratio of the fluorescent images but also leading to wrong interpretations.201121559297
paneth cell α-defensins in enteric innate immunity.paneth cells at the base of small intestinal crypts of lieberkühn secrete high levels of α-defensins in response to cholinergic and microbial stimuli. paneth cell α-defensins are broad spectrum microbicides that function in the extracellular environment of the intestinal lumen, and they are responsible for the majority of secreted bactericidal peptide activity. paneth cell α-defensins confer immunity to oral infection by salmonella enterica serovar typhimurium, and they are major determinants of ...201121560070
crystallographic and microcalorimetric analyses reveal the structural basis for high arginine specificity in the salmonella enterica serovar typhimurium periplasmic binding protein stm4351. 201121560168
food-specific attribution of selected gastrointestinal illnesses: estimates from a canadian expert elicitation survey.abstract the study used a structured expert elicitation survey to derive estimates of food-specific attribution for nine illnesses caused by enteric pathogens in canada. it was based on a similar survey conducted in the united states and focused on campylobacter spp., escherichia coli o157:h7, listeria monocytogenes, nontyphoidal salmonella enterica, shigella spp., vibrio spp., yersinia enterocolitica, cryptosporidium parvum, and norwalk-like virus. a snowball approach was used to identify food ...201121561379
virulotyping of salmonella enterica serovar napoli strains isolated in italy from human and nonhuman sources.abstract salmonella enterica serovar napoli is an emerging serovar in italy, france, and switzerland, but little is known about its pathogenicity to humans. a collection of 112 strains of salmonella napoli isolated in italy from human cases, foods of animal origin, and the environment have been characterized by the detection of a set of virulence genes, pulsed-field gel electrophoresis (pfge), and antibiotic susceptibility. all the strains examined were susceptible to all the antimicrobials test ...201121561382
receptor-transporter interactions of canonical atp-binding cassette import systems in prokaryotes.atp-binding cassette (abc) transport systems mediate the translocation of solutes across biological membranes at the expense of atp. they share a common modular architecture comprising two pore-forming transmembrane domains and two nucleotide binding domains. in prokaryotes, abc transporters are involved in the uptake of a large variety of chemicals, including nutrients, osmoprotectants and signal molecules. in pathogenic bacteria, some abc importers are virulence factors. canonical abc import s ...201121561685
quantitative proteomic analysis of salmonella enterica serovar typhimurium under phop/phoq activation conditions.the phop/phoq two-component system plays a central regulatory role in the pathogenesis of salmonella enterica serovar typhimurium (s. typhimurium), and it can be activated by low mg(2+) concentrations and sublethal concentrations of cationic antimicrobial peptides (camp). therefore, these two phop/phoq activation signals are considered as in vivo environmental cues sensed by s. typhimurium for adaptation and survival. in this work, we conducted a silac (stable isotope labeling by amino acids in ...201121563813
ethidium bromide efflux by salmonella: modulation by metabolic energy, ph, ions and phenothiazines.the main efflux pump of salmonella enterica serotype enteritidis, which obtains its energy for the extrusion of noxious agents from the proton-motive force, was studied with the aid of an ethidium bromide (etbr) semi-automated method under conditions that define the role of metabolic energy, ions and ph in the extrusion of the universal substrate etbr. the results obtained in this study indicate that in minimal medium containing sodium at ph 5 efflux of etbr is independent of glucose, whereas at ...201121565465
x-ray crystallography and isothermal titration calorimetry studies of the salmonella zinc transporter zntb.the zntb zn(2+) efflux system is important for maintenance of zn(2+) homeostasis in enterobacteria. we report crystal structures of zntb cytoplasmic domains from salmonella enterica serovar typhimurium (stzntb) in dimeric and physiologically relevant homopentameric forms at 2.3 å and 3.1 å resolutions, respectively. the funnel-like structure is similar to that of the homologous thermotoga maritima cora mg(2+) channel and a vibrio parahaemolyticus zntb (vpzntb) soluble domain structure. however, ...201121565704
2008 outbreak of salmonella saintpaul infections associated with raw produce.raw produce is an increasingly recognized vehicle for salmonellosis. we investigated a nationwide outbreak that occurred in the united states in 2008.201121345092
identification of a salmonellosis outbreak by means of molecular sequencing. 201121345093
salmonella enterica serotype virchow associated with human infections in switzerland: 2004-2009.salmonellosis is one of the most important foodborne diseases and a major threat to public health. salmonella serotype virchow ranks among the top five serovars in europe.201121345197
a comparison of transmission characteristics of salmonella enterica serovar enteritidis between pair-housed and group-housed laying hens.abstract: human cases of bacterial gastro-enteritis are often caused by the consumption of eggs contaminated with salmonella species, mainly salmonella enterica serovar enteriditis (salmonella enteritidis). to reduce human exposure, in several countries worldwide surveillance programmes are implemented to detect colonized layer flocks. the sampling schemes are based on the within-flock prevalence, and, as this changes over time, knowledge of the within-flock dynamics of salmonella enteritidis is ...201121345201
po157_sal, a novel conjugative plasmid detected in outbreak isolates of escherichia coli o157:h7.in addition to the large virulence plasmid po157, a novel 38-kb conjugative plasmid, po157_sal, was identified and sequenced from an escherichia coli o157:h7 outbreak-associated chinese isolate that shares high similarity with a plasmid in salmonella enterica serovar agona. the plasmid was found in 15 of 326 isolates, 12 of which were of the same pulsed-field gel electrophoresis type.201121346051
salmonella enterica serovar typhimurium lacking hfq gene confers protective immunity against murine typhoid.salmonella enterica is an important enteric pathogen and its various serovars are involved in causing both systemic and intestinal diseases in humans and domestic animals. the emergence of multidrug-resistant strains of salmonella leading to increased morbidity and mortality has further complicated its management. live attenuated vaccines have been proven superior over killed or subunit vaccines due to their ability to induce protective immunity. of the various strategies used for the generation ...201121347426
a mutation in the poxa gene of salmonella enterica serovar typhimurium alters protein production, elevates susceptibility to environmental challenges, and decreases swine colonization.control of foodborne salmonella within the farm-retail continuum is a complex issue since over 2500 serovars of salmonella exist, the host range of salmonella spp. varies greatly, and salmonella is environmentally ubiquitous. to identify salmonella enterica serovar typhimurium (salmonella typhimurium) genes important for pathogen survival, our research group previously screened a signature-tagged mutagenesis bank in an ex vivo swine stomach content assay. a mutation in the poxa gene, a member of ...201121348575
cellular aspects of immunity to intracellular salmonella enterica.salmonella enterica is a frequent gastrointestinal pathogen with ability to cause diseases ranging from local gastrointestinal inflammation and diarrhea to life-threatening typhoid fever. salmonella is an invasive, facultative intracellular pathogen that infects various cell types of the host and can survive and proliferate in different populations of immune cells. during pathogenesis, salmonella is confronted with various lines of immune defense. to successfully colonize host organisms, the pat ...201121349094
immunity to salmonellosis.salmonella enterica is a genetically broad species harboring isolates that display considerable antigenic heterogeneity and significant differences in virulence potential. salmonella generally exhibit an invasive potential and they can survive for extended periods within cells of the immune system. they cause acute or chronic infections that can be local (e.g. gastroenteritis) or systemic (e.g. typhoid). in vivo salmonella infections are complex with multiple arms of the immune system being enga ...201121349095
salmonella enterica strains belonging to o serogroup 1,3,19 induce chlorosis and wilting of arabidopsis thaliana leaves.the number of outbreaks and illness linked to the consumption of contaminated salad leaves have increased dramatically in the last decade. escherichia coli and salmonella enterica are the most common food-borne pathogens linked to consumption of fresh produce. different serovars of s. enterica subspecies enterica have been shown to bind the surface of salad leaves, to exhibit tropism towards the stomata and to invade leaves and reach the underlying mesophyll. however the consequences of leaf inv ...201121349136
genetic analysis of the bacterial hook-capping protein flgd responsible for hook assembly.flgd of salmonella enterica is a 232 aa protein that acts as the hook cap to promote assembly of flge into the hook structure. the n-terminal 86 residues (flgd(n)) complement flgd mutants, albeit to a small degree. however, little is known about the role of the c-terminal region of flgd (flgd(c)). here we isolated pseudorevertants from salmonella flge mutants. about half of the extragenic mutations lay within flgd(c) and only one in flgd(n). these suppressor mutations prevented mutant flge subun ...201121349976
function-specific accelerations in rates of sequence evolution suggest predictable epistatic responses to reduced effective population size.changes in effective population size impinge on patterns of molecular evolution. notably, slightly deleterious mutations are more likely to drift to fixation in smaller populations, which should typically also lead to an overall acceleration in the rates of evolution. this prediction has been validated empirically for several endosymbiont and island taxa. here, we first show that rate accelerations are also evident in bacterial pathogens whose recent shifts in virulence make them prime candidate ...201121349981
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