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genetic dissection of the ity3 locus identifies a role for ncf2 co-expression modules and suggests selp as a candidate gene underlying the ity3.2 locus.typhoid fever and salmonellosis, which are caused by salmonella typhi and typhimurium, respectively, are responsible for significant morbidity and mortality in both developed and developing countries. we model typhoid fever using mice infected with salmonella typhimurium, which results in a systemic disease, whereby the outcome of infection is variable in different inbred strains of mice. this model recapitulates several clinical aspects of the human disease and allows the study of the host resp ...201425161653
a nutrient-tunable bistable switch controls motility in salmonella enterica serovar typhimurium.many bacteria are motile only when nutrients are scarce. in contrast, salmonella enterica serovar typhimurium is motile only when nutrients are plentiful, suggesting that this bacterium uses motility for purposes other than foraging, most likely for host colonization. in this study, we investigated how nutrients affect motility in s. enterica and found that they tune the fraction of motile cells. in particular, we observed coexisting populations of motile and nonmotile cells, with the distributi ...201425161191
electroporation-based delivery of cell-penetrating peptide conjugates of peptide nucleic acids for antisense inhibition of intracellular bacteria.cell penetrating peptides (cpps) have been used for a myriad of cellular delivery applications and were recently explored for delivery of antisense agents such as peptide nucleic acids (pnas) for bacterial inhibition. although these molecular systems (i.e. cpp-pnas) have shown ability to inhibit growth of bacterial cultures in vitro, they show limited effectiveness in killing encapsulated intracellular bacteria in mammalian cells such as macrophages, presumably due to difficulty involved in the ...201425160797
modulation of biofilm-formation in salmonella enterica serovar typhimurium by the periplasmic dsba/dsbb oxidoreductase system requires the ggdef-eal domain protein stm3615.in salmonella enterica serovar typhimurium (s. typhimurium), biofilm-formation is controlled by the cytoplasmic intracellular small-molecular second messenger cyclic 3', 5'-di- guanosine monophosphate (c-di-gmp) through the activities of ggdef and eal domain proteins. here we describe that deleting either dsba or dsbb, respectively encoding a periplasmic protein disulfide oxidase and a cytoplasmic membrane disulfide oxidoreductase, resulted in increased biofilm-formation on solid medium. this in ...201425153529
antimutagenicity of methanolic extracts from anemopsis californica in relation to their antioxidant activity.anemopsis californica has been used empirically to treat infectious diseases. however, there are no antimutagenic evaluation reports on this plant. the present study evaluated the antioxidant activity in relation to the mutagenic and antimutagenic activity properties of leaf (lme) and stem (sme) methanolic extracts of a. californica collected in the central mexican state of querétaro. antioxidant properties and total phenols of extracts were evaluated using dpph (1,1-diphenyl-2-picrylhydrazyl) a ...201425152760
evaluation of the adjuvant activity of propranolol, a beta-adrenergic receptor antagonist, on efficacy of a malaria vaccine model in balb/c mice.we have previously shown the adjuvant activity of propranolol (prp) (a beta-adrenergic receptor antagonist) using a vaccine model for salmonella typhimurium. in this study prp was used as an adjuvant in combination with plasmodium berghei (p. berghei) whole blood stage (pwbs) antigens. balb/c mice were immunized three times with a 2-week interval, either pwbs vaccine alone or in combination with the adjuvant alum or propranolol. the control group received phosphate buffered saline. evaluation of ...201425150071
low-shear force associated with modeled microgravity and spaceflight does not similarly impact the virulence of notable bacterial pathogens.as their environments change, microbes experience various threats and stressors, and in the hypercompetitive microbial world, dynamism and the ability to rapidly respond to such changes allow microbes to outcompete their nutrient-seeking neighbors. viewed in that light, the very difference between microbial life and death depends on effective stress response mechanisms. in addition to the more commonly studied temperature, nutritional, and chemical stressors, research has begun to characterize m ...201425149449
antibacterial effect of silver nanoparticles against four foodborne pathogens.there is increased demand for improved disinfection methods due to microorganisms resistant to multiple antimicrobial agents. numerous types of disinfectants are available with different properties; but the proper disinfectant must be carefully selected for any specific application to obtain the desired antimicrobial effect.201425147658
high-throughput assay to phenotype salmonella enterica typhimurium association, invasion, and replication in macrophages.salmonella species are zoonotic pathogens and leading causes of food borne illnesses in humans and livestock. understanding the mechanisms underlying salmonella-host interactions are important to elucidate the molecular pathogenesis of salmonella infection. the gentamicin protection assay to phenotype salmonella association, invasion and replication in phagocytic cells was adapted to allow high-throughput screening to define the roles of deletion mutants of salmonella enterica serotype typhimuri ...201425146526
phytotoxic and antibacterial metabolites from fusarium proliferatum zs07 isolated from the gut of long-horned grasshoppers.in the proceeding of screening new bioactive natural products, the ethyl acetate extract of the fermentation broth of fusarium proliferatum zs07, a fungus residing in the gut of long-horned grasshoppers (tettigonia chinensis), was found possessing selective phytotoxic activity against the radicle growth of amaranthus retroflexus l. bioactivity-guided fractionation lead to the isolation of six fungal metabolites 1-6, including a new polyketide derivate o-methylated sma93 (2) and five known compou ...201425146301
genome sequence of salmonella phage 9na.the virulent double-stranded dna (dsdna) bacteriophage 9na infects salmonella enterica serovar typhimurium and has a long noncontractile tail. we report its complete 52,869-bp genome sequence. phage 9na and two closely related s. enterica serovar newport phages represent a tailed phage type whose molecular lifestyle has not yet been studied in detail.201425146133
antimicrobial and mechanical properties of β-cyclodextrin inclusion with essential oils in chitosan films.chitosan films incorporated with various concentrations of the complex of β-cyclodextrin and essential oils (β-cd/eo) were prepared and investigated for antimicrobial, mechanical, and physical properties. four bacterial strains that commonly contaminate food products were chosen as target bacteria to evaluate the antimicrobial activity of the prepared films. the incorporation of β-cd/eo significantly increased the antimicrobial activities of the chitosan films against escherichia coli, salmonell ...201425141280
antimicrobial light-activated materials: towards application for food and environmental safety.to produce light-activated antimicrobial materials composed of the photodynamic dye phloxine b incorporated into paper or cellulose membranes and to investigate ability of these materials to decrease bacterial loads on their surfaces as well as on food surfaces that were in contact with these materials under illumination with regular white light.201425139147
bistable expression of virulence genes in salmonella leads to the formation of an antibiotic-tolerant subpopulation.phenotypic heterogeneity can confer clonal groups of organisms with new functionality. a paradigmatic example is the bistable expression of virulence genes in salmonella typhimurium, which leads to phenotypically virulent and phenotypically avirulent subpopulations. the two subpopulations have been shown to divide labor during s. typhimurium infections. here, we show that heterogeneous virulence gene expression in this organism also promotes survival against exposure to antibiotics through a bet ...201425136970
comparative analysis of salmonella susceptibility and tolerance to the biocide chlorhexidine identifies a complex cellular defense network.chlorhexidine is one of the most widely used biocides in health and agricultural settings as well as in the modern food industry. it is a cationic biocide of the biguanide class. details of its mechanism of action are largely unknown. the frequent use of chlorhexidine has been questioned recently, amidst concerns that an overuse of this compound may select for bacteria displaying an altered susceptibility to antimicrobials, including clinically important anti-bacterial agents. we generated a sal ...201425136333
synthesis of metallo-β-lactamase vim-2 is associated with a fitness reduction in salmonella enterica serovar typhimurium.antibiotic resistance, especially due to β-lactamases, has become one of the main obstacles in the correct treatment of salmonella infections; furthermore, antibiotic resistance determines a gain of function that may encompass a biological cost, or fitness reduction, to the resistant bacteria. the aim of this work was to determine in vitro if the production of the class b β-lactamase vim-2 determined a fitness cost for salmonella enterica serovar typhimurium. to that end the gene blavim-2 was cl ...201425136026
lipopolysaccharides belonging to different salmonella serovars are differentially capable of activating toll-like receptor 4.salmonella enterica subsp. enterica serovar (serotype) abortusovis is a member of the enterobacteriaceae. this serotype is naturally restricted to ovine species and does not infect humans. limited information is available about the immune response of sheep to s. abortusovis. s. abortusovis, like salmonella enterica subsp. enterica serovar typhi, causes a systemic infection in which, under natural conditions, animals are not able to raise a rapid immune response. failure to induce the appropriate ...201425135686
coptidis rhizome and si jun zi tang can prevent salmonella enterica serovar typhimurium infection in mice.salmonella, a common zoonotic pathogen, causes gastroenteritis in both humans and animals. traditional chinese medicine (tcm) has been used to improve gastrointestinal dysfunction and to modify the immune response to inflammation for centuries. this study used six herbal plants and four tcm formulae to rate their efficacy in preventing s. typhimurium infection via mouse model. minimum bactericidal concentration (mbc) of coptidis rhizome (cr) against the reference strain tallied 12.5 mg/ml and ag ...201425133542
antibiotic treatment selects for cooperative virulence of salmonella typhimurium.antibiotics are powerful therapeutics but are not equally effective against all cells in bacterial populations. bacteria that express an antibiotic-tolerant phenotype ("persisters") can evade treatment [1]. persisters can cause relapses of the infection after the end of the therapy [2]. it is still poorly understood whether persistence affects the evolution of bacterial virulence. during infections, persisters have been found preferentially at particular sites within the host [3, 4]. if bacteria ...201425131673
the role of clpp, rpos and csra in growth and filament formation of salmonella enterica serovar typhimurium at low temperature.salmonellae are food-borne pathogens of great health and economic importance. to pose a threat to humans, salmonellae normally have to cope with a series of stressful conditions in the food chain, including low temperature. in the current study, we evaluated the importance of the clp proteolytic complex and the carbon starvation protein, csra, for the ability of salmonella typhimurium to grow at low temperature.201425123657
understanding the basis of antibiotic resistance: a platform for drug discovery.there are numerous genes in salmonella enterica serovar typhimurium that can confer resistance to fluoroquinolone antibiotics, including those that encode topoisomerase proteins, the primary targets of this class of drugs. however, resistance is often multifactorial in clinical isolates and it is not uncommon to also detect mutations in genes that affect the expression of proteins involved in permeability and multi-drug efflux. the latter mechanism, mediated by tripartite efflux systems, such as ...201425122880
effect of human immunodeficiency virus infection on plasma bactericidal activity against salmonella enterica serovar typhimurium.individuals with human immunodeficiency virus (hiv) infection have increased susceptibility to invasive disease caused by salmonella enterica serovar typhimurium. studies from africa have suggested that this susceptibility is related in part to the development of a high level of lipopolysaccharide (lps)-specific igg that is able to inhibit the killing of s. typhimurium by bactericidal antibodies in healthy individuals. to explore this issue further, we examined the bactericidal activity against ...201425121777
noncanonical inflammasome activation of caspase-4/caspase-11 mediates epithelial defenses against enteric bacterial pathogens.inflammasome-mediated host defenses have been extensively studied in innate immune cells. whether inflammasomes function for innate defense in intestinal epithelial cells, which represent the first line of defense against enteric pathogens, remains unknown. we observed enhanced salmonella enterica serovar typhimurium colonization in the intestinal epithelium of caspase-11-deficient mice, but not at systemic sites. in polarized epithelial monolayers, sirna-mediated depletion of caspase-4, a human ...201425121752
epithelium-intrinsic naip/nlrc4 inflammasome drives infected enterocyte expulsion to restrict salmonella replication in the intestinal mucosa.the gut mucosal epithelium separates the host from the microbiota, but enteropathogens such as salmonella typhimurium (s.tm) can invade and breach this barrier. defenses against such acute insults remain incompletely understood. using a murine model of salmonella enterocolitis, we analyzed mechanisms limiting pathogen loads in the epithelium during early infection. although the epithelium-invading s.tm replicate initially, this intraepithelial replicative niche is restricted by expulsion of infe ...201425121751
nitric oxide from ifnγ-primed macrophages modulates the antimicrobial activity of β-lactams against the intracellular pathogens burkholderia pseudomallei and nontyphoidal salmonella.our investigations show that nonlethal concentrations of nitric oxide (no) abrogate the antibiotic activity of β-lactam antibiotics against burkholderia pseudomallei, escherichia coli and nontyphoidal salmonella enterica serovar typhimurium. no protects b. pseudomallei already exposed to β-lactams, suggesting that this diatomic radical tolerizes bacteria against the antimicrobial activity of this important class of antibiotics. the concentrations of no that elicit antibiotic tolerance repress co ...201425121731
saccharomyces boulardii modifies salmonella typhimurium traffic and host immune responses along the intestinal tract.salmonella enterica serovar typhimurium (st) is an enteropathogenic gram-negative bacterium that causes infection following oral ingestion. st spreads rapidly along the gastrointestinal tract (git) and invades the intestinal epithelium to ultimately reach internal body organs. the probiotic yeast saccharomyces boulardii biocodex (s.b-b) is prescribed for prophylaxis of diarrheal infectious diseases. we previously showed that s.b-b prevents weight loss in st-infected mice and significantly decrea ...201425118595
monophasic expression of flic by salmonella 4,[5],12:i:- dt193 does not alter its pathogenicity during infection of porcine intestinal epithelial cells.non-typhoidal serotypes of salmonella enterica remain important food-borne pathogens worldwide and the frequent emergence of epidemic strains in food-producing animals is a risk to public health. in recent years, salmonella 4,[5],12:i:- isolates, expressing only phase 1 (flic) of the two flagellar antigens, have emerged and increased in prevalence worldwide. in europe, the majority of 4,[5],12:i:- isolates belong to phage types dt193 and dt120 of salmonella typhimurium and pigs have been identif ...201425118251
a small intestinal organoid model of non-invasive enteric pathogen-epithelial cell interactions.organoids mirror in vivo tissue organization and are powerful tools to investigate the development and cell biology of the small intestine. however, their application for the study of host-pathogen interactions has been largely unexplored. we have established a model using microinjection of organoids to mimic enteric infection, allowing for direct examination of pathogen interactions with primary epithelial cells in the absence of confounding variables introduced by immune cells or the commensal ...201525118165
limited role for asc and nlrp3 during in vivo salmonella typhimurium infection.the inflammasome is an intracellular protein complex triggered by exposure to intracellular pathogens, its components or other endogenous proteins. it leads to the activation of and subsequent release of proinflammatory cytokines such as il-1β and il-18. s. typhimurium is a gram-negative intracellular bacterium, which is known to trigger inflammasome assembly via recognition by the cytosolic receptors, nlrp3 and nlrc4 (which act via the adaptor protein, asc) to induce cell death and cytokine rel ...201425115174
evaluation of the biological activity of novel monocationic fluoroaryl-2,2'-bichalcophenes and their analogues.a series of bichalcophene fluorobenzamidines 5a-e was synthesized from the corresponding mononitriles 4a-e via a direct reaction with lithium bis(trimethylsilyl)amide lin(tms)2 followed by de-protection with ethanolic hcl (gas). bichalcophene fluorobenzonitriles 4a-e were prepared adopting a stille coupling reaction between the bromo compounds 3a-c and 2-(tri-n-butylstannyl)furan or analogues. as an approach to drug discovery, the structure-antimutagenicity relationship of novel fluoroarylbichal ...201425114506
improvement of antibacterial activity of some sulfa drugs through linkage to certain phthalazin-1(2h)-one scaffolds.rab1 5 is a lead antibacterial agent in which trimethoprim is linked to phthalazine moiety. similarly, our strategy in this research depends on the interconnection between some sulfa drugs and certain phthalazin-1(2h)-one scaffolds in an attempt to enhance their antibacterial activity. this approach was achieved through the combination of 4-substituted phthalazin-1(2h)-ones 9a, b or 14a, b with sulfanilamide 1a, sulfathiazole 1b or sulfadiazine 1c through amide linkers 6a, b to produce the targe ...201425113876
antibacterial tetraoxygenated xanthones from the immature fruits of garcinia cowa.a phytochemical investigation of the acetone extract from the immature fruits of garcinia cowa led to the isolation of two novel tetraoxygenated xanthones, garcicowanones a (1) and b (2), together with eight known tetraoxygeanted xanthones. their structures were determined by spectroscopic analysis. all isolated compounds were evaluated for their antibacterial activity against bacillus cereus tistr 688, bacillus subtilis tistr 008, micrococcus luteus tistr 884, staphylococcus aureus tistr 1466, ...201425110196
mutagenicity and clastogenicity evaluation of metaphenoxy benzyl chloride by ames and micronucleus assays.metaphenoxy benzyl chloride (3-pbc; cas # 53874-66-1) is a commonly used intermediate in organic synthesis and is a widely used chemical building block. there is likelihood of human contact with 3-pbc in the process of organic or pesticide synthesis and even through as impurity in the product. further, this chemical has been reported to be found in water reservoirs causing a threat to aqueous flaura and fauna. genotoxic alert has been suspected for the chemical 3-pbc based on its structure hence ...201525109298
characterization of an unusual salmonella phage type dt7a and report of a foodborne outbreak of salmonellosis.salmonella enterica subsp. enterica serovar 4,[5],12,i:- is a monophasic variant of salmonella typhimurium and its occurrence has markedly increased in several european countries in the last ten years. in june 2011, an outbreak of salmonella 4,[5],12,i:- was reported among attendees of a wedding reception in the north-east of italy. the source of this outbreak was identified as a cooked pork product served during the wedding reception. all salmonella isolates from humans and the contaminated por ...201425108760
enhanced inactivation of food-borne pathogens in ready-to-eat sliced ham by near-infrared heating combined with uv-c irradiation and mechanism of the synergistic bactericidal action.the objective of the study described in this article was, first, to investigate the effect of the simultaneous application of near-infrared (nir) heating and uv irradiation on inactivation of escherichia coli o157:h7, salmonella enterica serovar typhimurium, and listeria monocytogenes in ready-to-eat (rte) sliced ham and as well as its effect on product quality and, second, to elucidate the underlying mechanisms of the synergistic bactericidal action of nir heating and uv irradiation. with the i ...201525107964
stress response of salmonella enterica serovar typhimurium to acidified nitrite.the antimicrobial action of the curing agent sodium nitrite (nano2), which is added as a preservative to raw meat products, depends on its conversion to nitric oxide and other reactive nitrogen species under acidic conditions. in this study, we used rna sequencing to analyze the acidified-nano2 shock and adaptive responses of salmonella enterica serovar typhimurium, a frequent contaminant in raw meat, considering parameters relevant for the production of raw-cured sausages. upon a 10-min exposur ...201425107963
modeling of scale-dependent bacterial growth by chemical kinetics approach.we applied the so-called chemical kinetics approach to complex bacterial growth patterns that were dependent on the liquid-surface-area-to-volume ratio (sa/v) of the bacterial cultures. the kinetic modeling was based on current experimental knowledge in terms of autocatalytic bacterial growth, its inhibition by the metabolite co2, and the relief of inhibition through the physical escape of the inhibitor. the model quantitatively reproduces kinetic data of sa/v-dependent bacterial growth and can ...201425105169
genome-scale co-expression network comparison across escherichia coli and salmonella enterica serovar typhimurium reveals significant conservation at the regulon level of local regulators despite their dissimilar lifestyles.availability of genome-wide gene expression datasets provides the opportunity to study gene expression across different organisms under a plethora of experimental conditions. in our previous work, we developed an algorithm called comodo (conserved modules across organisms) that identifies conserved expression modules between two species. in the present study, we expanded comodo to detect the co-expression conservation across three organisms by adapting the statistics behind it. we applied comodo ...201425101984
development of ssdna aptamers for the sensitive detection of salmonella typhimurium and salmonella enteritidis.salmonella enterica subsp. enterica ser. enteritidis and salmonella enterica subsp. enterica ser. typhimurium are the most common and severe food-borne pathogens responsible for causing salmonellosis in humans and animals. the development of an early and ultra-sensitive detection system is the first critical step in controlling this disease. to accomplish this, we used the cell systematic evolution of ligands by exponential enrichment (cell-selex) technique to identify single-stranded dna (ssdna ...201425096391
effect of simulated gastrointestinal conditions on biofilm formation by salmonella 1,4,[5],12:i:-.salmonella typhimurium 1,4,[5],12:i:- is a major serovar responsible for human salmonellosis whose biofilm-forming ability, influenced by environmental conditions like those found in the gastrointestinal tract, is one of the main contributing factors to its ability to persist in the host and thus one of the main causes of chronic relapsing infections. most studies to evaluate biofilm formation are performed in microtiter assays using standard media. however, no reports are available on the abili ...201425093197
bacterial maximum non-inhibitory and minimum inhibitory concentrations of different water activity depressing solutes.the nacl mnics (maximum non-inhibitory concentrations) and mics (minimum inhibitory concentrations) for growth of various strains of six bacterial species were determined and then compared with those obtained for seven other solutes. the influence of prior growth conditions on the mnics and mics was also evaluated. no significant changes on the mnics and mics were found among the strains studied within each species. among all factors investigated, only growth phase -for gram-negatives- and growt ...201425090605
inhibition of escherichia coli tryptophan indole-lyase by tryptophan homologues.we have designed, synthesized and evaluated homotryptophan analogues as possible mechanism-based inhibitors for escherichia coli tryptophan indole-lyase (tryptophanase, til, e.c. 4.1.99.1). as a quinonoid structure is an intermediate in the reaction mechanism of til, we anticipated that homologation of the physiological substrate, l-trp would provide analogues resembling the transition state for β-elimination, and potentially inhibit til. our results demonstrate that l-homotryptophan (1a) is a m ...201425088962
interaction of the carbon monoxide-releasing molecule ru(co)3cl(glycinate) (corm-3) with salmonella enterica serovar typhimurium: in situ measurements of carbon monoxide binding by integrating cavity dual-beam spectrophotometry.carbon monoxide (co) is a toxic gas that binds to haems, but also plays critical signalling and cytoprotective roles in mammalian systems; despite problems associated with systemic delivery by inhalation of the gas, it may be employed therapeutically. co delivered to cells and tissues by co-releasing molecules (co-rms) has beneficial and toxic effects not mimicked by co gas; co-rms are also attractive candidates as novel antimicrobial agents. salmonella enterica serovar typhimurium is an enterop ...201425085864
lethal synergy involving bicyclomycin: an approach for reviving old antibiotics.one way to address the growing problem of antimicrobial resistance is to revive old compounds that may have intrinsic lethal activity that is obscured by protective factors. bicyclomycin is an old inhibitor of the rho transcription terminator that by itself shows little rapid lethal activity. however, bicyclomycin participates in bacteriostatic synergy, which raises the possibility that conditions for lethal synergy may exist, perhaps through a suppression of protective factors.201425085655
monitoring of volatile and non-volatile urban air genotoxins using bacteria, human cells and plants.urban air contains many mutagenic pollutants. this research aimed to investigate the presence of mutagens in the air by short-term mutagenicity tests using bacteria, human cells and plants. inflorescences of tradescantia were exposed to air in situ for 6h, once a month from january to may, to monitor volatile compounds and micronuclei frequency was computed. on the same days pm10 was collected continuously for 24h. half of each filter was extracted with organic solvents and studied by means of t ...201525084136
shedding of zoonotic pathogens and analysis of stomach contents in great cormorants (phalacrocorax carbo sinensis) from switzerland between 2007 and 2012.208 healthy great cormorants (phalacrocorax carbo sinensis) shot during 5 consecutive hunting seasons from 2007/2008 until 2011/2012 were tested for newcastle disease virus (apmv-1), avian influenza virus (aiv), chlamydiae, and salmonella spp. in addition, stomach contents were gross macroscopically examined. none of the birds was positive for apmv1, aiv or chlamydiae. twice salmonella enterica subsp. enterica serovar typhimurium and once a rough mutant of salmonella typhimurium were found. stom ...201425082636
new compounds, 6-hydroxykarahanaenone and 10-hydroxykarahanaenone, from biotransformation of karahanaenone by cyp2a6.the in vitro biotransformation of karahanaenone was examined in cytochrome p450 (cyp) 2a6. the biotransformation of karahanaenone by cyp2a6 was investigated by gas chromatography (gc) and gas chromatography-mass spectrometry (gc-ms). karahanaenone was found to be oxidized to two metabolites by cyp2a6. in order to produce large quantity of metabolites by cyp2a6, the biotransformation of karahanaenone by salmonella typhimurium oy1002/2a6 was investigated. similarly, two metabolites were confirmed ...201425082308
direct regulation of the pefi-srgc operon encoding the rck invasin by the quorum-sensing regulator sdia in salmonella typhimurium.one important step for the pathogenesis of salmonella is its ability to penetrate host cells. recently, a new entry system involving the outer membrane protein rck has been characterized. previous studies have shown that the pefi-srgc locus, which contains rck, was regulated by the temperature and sdia, the transcriptional regulator of quorum sensing in salmonella. to decipher the regulation of rck by sdia, we first confirmed the operon organization of the pefi-srgc locus. using plasmid-based tr ...201425080967
iron at the interface of immunity and infection.both, mammalian cells and microbes have an essential need for iron, which is required for many metabolic processes and for microbial pathogenicity. in addition, cross-regulatory interactions between iron homeostasis and immune function are evident. cytokines and the acute phase protein hepcidin affect iron homeostasis leading to the retention of the metal within macrophages and hypoferremia. this is considered to result from a defense mechanism of the body to limit the availability of iron for e ...201425076907
method to conjugate polysaccharide antigens to surfaces for the detection of antibodies.a new generic method for the conjugation of lipopolysaccharide (lps)-derived polysaccharide antigens from gram-negative bacteria has been developed using salmonella as a model. after removal of lipid a from the lps by mild acidolysis, the polysaccharide antigen was conjugated to polystyrene microbeads modified with n-alkyl hydroxylamine and n-alkyl-o-methyl hydroxylamine surface groups by incubation of antigen and beads for 16 h at 40 °c without the need for coupling agents. the efficiency of th ...201425076184
generalized linear mixed model analysis of risk factors for contamination of moisture-enhanced pork with campylobacter jejuni and salmonella enterica typhimurium.translocation of foodborne pathogens into the interior tissues of pork through moisture enhancement may be of concern if the meat is undercooked. in the present study, a five-strain mixture of campylobacter jejuni or salmonella enterica typhimurium was evenly spread on the surface of fresh pork loins. pork loins were injected, sliced, vacuum packaged, and stored. after storage, sliced pork was cooked by traditional grilling. survival of salmonella typhimurium and c. jejuni in the interior tissue ...201425072538
pre-clinical in vitro and in vivo safety evaluation of bovine whey derived osteopontin, lacprodan® opn-10.lacprodan® opn-10 is a proprietary whey-based protein product that contains bovine-derived osteopontin (opn), found in human milk and other bodily tissues. in vitro genotoxicity tests conducted according to accepted guidelines at up to 5000μg/plate opn failed to induce genetic mutations in salmonella typhimurium strains and escherichia coli strain and did not induce chromosomal aberrations or cytotoxicity in human lymphocytes. administration of an acute dose of lacprodan® opn-10 (2300mg/kg body ...201425072164
mucosal inflammatory response to salmonella typhimurium infection.the human intestinal epithelium consists of a single layer of epithelial cells that forms a barrier against food antigens and the resident microbiota within the lumen. this delicately balanced organ functions in a highly sophisticated manner to uphold the fidelity of the intestinal epithelium and to eliminate pathogenic microorganisms. on the luminal side, this barrier is fortified by a thick mucus layer, and on the serosal side exists the lamina propria containing a resident population of immun ...201425071772
tc52 amino-terminal-domain dna carried by attenuated salmonella enterica serovar typhimurium induces protection against a trypanosoma cruzi lethal challenge.in this work we immunized mice with dna encoding full-length tc52 or its amino- or carboxy-terminal (n- and c-term, respectively) domain carried by attenuated salmonella as a dna delivery system. as expected, salmonella-mediated dna delivery resulted in low antibody titers and a predominantly th1 response, as shown by the ratio of igg2a/igg1-specific antibodies. despite modest expression of tc52 in trypomastigotes, the antibodies elicited by vaccination were able to mediate lysis of the trypomas ...201425069980
rice hull smoke extract protects mice against a salmonella lipopolysaccharide-induced endotoxemia.endotoxemia (sepsis, septic shock) is an inflammatory, virulent disease that results mainly from infection by gram-negative bacteria. the present study investigates the inhibitory effects of a rice hull smoke extract (rhse) against murine endotoxemia induced by salmonella lipopolysaccharide and d-galactosamine (lps/galn). pretreatment of the mice with rhse via dietary administration for 2 weeks resulted in the suppression (in %) of lps/galn-induced catalase by 70.7, superoxide dismutase (sod) by ...201425068861
trs-based pcr as a potential tool for inter-serovar discrimination of salmonella enteritidis, s. typhimurium, s. infantis, s. virchow, s. hadar, s. newport and s. anatum.salmonella enterica subsp. enterica comprises a number of serovars, many of which pose an epidemiological threat to humans and are a worldwide cause of morbidity and mortality. most reported food infection outbreaks involve the serovars salmonella enteritidis and salmonella typhimurium. rapid identification to determine the primary sources of the bacterial contamination is important to the improvement of public health. in recent years, many dna-based techniques have been applied to genotype salm ...201425063578
wound healing potential of antibacterial microneedles loaded with green tea extracts.this study evaluates the utility of an antibacterial microneedle composed of green tea (gt) extract and hyaluronic acid (ha), for the efficient delivery of gt. these microneedles have the potential to be a patient-friendly method for the conventional sustained release of drugs. in this study, a fabrication method using a mold-based technique to produce gt/ha microneedles with a maximum area of ~50mm(2) with antibacterial properties was used to manufacture transdermal drug delivery systems. fouri ...201425063177
whole-genome sequence of cmy-2 β-lactamase-producing salmonella enterica serovar typhimurium strain l-3553.salmonella enterica serovar typhimurium pulsed-field gel electrophoresis cluster vii has been isolated from cattle populations in japan since the mid-2000s. some cluster vii isolates exhibited extended-spectrum cephalosporin resistance defined by the blacmy-2 gene located in a chromosomal genomic island, gi-vii-6. we determined the whole-genome sequence of strain l-3553 as the reference strain.201425059867
dissecting the cyclic di-guanylate monophosphate signalling network regulating motility in salmonella enterica serovar typhimurium.flagella-mediated swimming and swarming motility in salmonella enterica serovar typhimurium is intercalated with the cyclic di-guanylate monophosphate (c-di-gmp) signalling network. in this study, we identified the ggdef domain proteins stm2672, stm4551 and stm1987 as key di-guanylate cyclases involved in regulation of motility in a δyhjh phosphodiesterase gene deletion mutant with elevated c-di-gmp levels inhibiting motility. surprisingly, these di-guanylate cyclases distinctively inhibited mot ...201525059628
salmonella enterica serovar typhimurium multidrug efflux pumps emrab and acref support the major efflux system acrab in decreased susceptibility to triclosan. 201425059442
anti-bacterial activity of achatina crp and its mechanism of action.the physiological role of c-reactive protein (crp), the classical acute-phase protein, is not well documented, despite many reports on biological effects of crp in vitro and in model systems in vivo. it has been suggested that crp protects mice against lethal toxicity of bacterial infections by implementing immunological responses. in achatina fulica crp is a constitutive multifunctional protein in haemolymph and considered responsible for their survival in the environment for millions of years. ...201425059037
structural and functional features of crl proteins and identification of conserved surface residues required for interaction with the rpos/σs subunit of rna polymerase.in many γ-proteobacteria, the rpos/σs sigma factor associates with the core rnap (rna polymerase) to modify global gene transcription in stationary phase and under stress conditions. the small regulatory protein crl stimulates the association of σs with the core rnap in escherichia coli and salmonella enterica serovar typhimurium, through direct and specific interaction with σs. the structural determinants of crl involved in σs binding are unknown. in the present paper we report the x-ray crysta ...201425056110
flavonoid detection in hydroethanolic extract of pouteria torta (sapotaceae) leaves by hplc-dad and the determination of its mutagenic activity.it is well known that phytotherapy has grown in popularity in recent years. because a drug cannot be administered without ensuring its effectiveness and safety, the standardization and regulation of phytotherapeutic drugs are required by the global market and governmental authorities. this article describes a simple and reliable high-performance liquid chromatography-diode array detection analysis method for the simultaneous detection of myricetin-3-o-β-d-galactopyranoside, myricetin-3-o-α-l-ara ...201425055245
the effect of knockout of sulfotransferases 1a1 and 1d1 and of transgenic human sulfotransferases 1a1/1a2 on the formation of dna adducts from furfuryl alcohol in mouse models.furfuryl alcohol is a rodent carcinogen present in numerous foodstuffs. sulfotransferases (sults) convert furfuryl alcohol into the dna reactive and mutagenic 2-sulfoxymethylfuran. sensitive techniques for the isotope-dilution ultra performance liquid chromatography-tandem mass spectrometry quantification of resulting dna adducts, e.g. n (2)-((furan-2-yl)methyl)-2'-deoxyguanosine (n (2)-mf-dg), were developed. to better understand the contribution of specific sult forms to the genotoxicity of fu ...201425053625
the salmonella typhimurium effector protein sope transiently localizes to the early scv and contributes to intracellular replication.salmonella enterica serovar typhimurium (s. tm) is a facultative intracellular pathogen that induces entry into non-phagocytic cells by a type iii secretion system (ttss) and cognate effector proteins. upon host cell entry, s. tm expresses a second ttss and subverts intracellular trafficking to create a replicative niche - the salmonella-containing vacuole (scv). sope, a guanidyl exchange factor (gef) for rac1 and cdc42, is translocated by the ttss-1 upon host cell contact and promotes entry thr ...201425052734
enhancement of vaccine efficacy by expression of a tlr5 ligand in the defined live attenuated francisella tularensis subsp. novicida strain u112δiglb::fljb.oral vaccination with the defined live attenuated francisella novicida vaccine strain u112δiglb has been demonstrated to induce protective immunity against pulmonary challenge with the highly human virulent francisella tularensis strain schu s4. however, this vaccination regimen requires a booster dose in mice and exhibits 50% protective efficacy in the fischer 344 rat model. to enhance the efficacy of this vaccine strain, we engineered u112δiglb to express the salmonella typhimurium fljb flagel ...201425050972
cytokines expression and nitric oxide production under induced infection to salmonella typhimurium in chicken lines divergently selected for cutaneous hypersensitivity.in the present study, the impact of salmonella typhimurium on cell-mediated immunity (cmi) was investigated in 5 week-old immuno divergent broiler lines selected for the high and low response to phytohemagglutinin-p. the immune response was assessed in peripheral-blood mononuclear cells (pbmcs) induced with salmonella typhimurium at different time intervals (0 h, 0.5 h, 2 h, 4 h, 6 h, 12 h and 24 h). the differential mrna expression patterns of ifn-γ, il-2 and inos were evaluated by quantitative ...201225049661
assessment of oligogalacturonide from citrus pectin as a potential antibacterial agent against foodborne pathogens.foodborne diseases are an important public health problem in the world. the bacterial resistance against presently used antibiotics is becoming a public health issue; hence, the discovery of new antimicrobial agents from natural sources attracts a lot of attention. antibacterial activities of oligogalacturonide from commercial microbial pectic enzyme (cpe) treated citrus pectin, which exhibits antioxidant and antitumor activities, against 4 foodborne pathogens including salmonella typhimurium, s ...201425048440
complete genome sequence of salmonella enterica serovar typhimurium vnp20009, a strain engineered for tumor targeting.a mutagenized and genetically modified derivative of salmonella enterica serovar typhimurium 14028s, vnp20009 (atcc 202165), is attenuated in host virulence and accumulates preferentially in tumors. here, we report the complete genome of this anticancer therapy agent consisting of one chromosome and one virulence plasmid. the major genetic features that distinguish vnp20009 from its parental strain are: an engineered msbb deletion, a 3'-extension in pyka, a tn10-caused 16.6-kbp inversion leading ...201425046822
the persistence of salmonella following desiccation under feed processing environmental conditions: a subject of relevance.although salmonella persistence has been predominantly linked to biofilm formation, the physiological state of salmonella should also be considered as a possible pathway for persistence and survival in the feed industry. hence, the purpose of this study was to assess the extent of viability of salmonella cells through long-term desiccation periods under conditions typically found in feed processing environments, and whether these same cells could resuscitate and cause salmonellosis in vivo. we s ...201425046569
generation of an attenuated salmonella-delivery strains expressing adhesin and toxin antigens for progressive atrophic rhinitis, and evaluation of its immune responses in a murine model.an expression/secretion plasmid containing genes encoding the fima, cp39, ptfa, toxa and f1p2 antigens associated with porcine pneumonic pasteurellosis and progressive atrophic rhinitis (par) was constructed and harbored in an attenuated salmonella typhimurium, which was used as the vaccine candidate. the immune responses induced by this delivery strain were investigated in a murine model. each antigen secreted from the delivery strain was confirmed by western blot analysis. thirty balb/c mice w ...201425045826
influence of lactobacillus pentosus s-pt84 ingestion on the mucosal immunity of healthy and salmonella typhimurium-infected mice.lactobacillus pentosus (l. pentosus) strain s-pt84, isolated from kyoto pickles, enhances splenic natural killer (nk) cell activity, and has high t-helper1 (th1) cytokine and type 1-ifn (ifn-α) inducing activity. in the present study, we investigated the influence of s-pt84 ingestion on the mucosal immunity of healthy and salmonella typhimurium (s. typhimurium)-infected mice. in the s. typhimurium infection model, numbers of s. typhimurium in feces and the spleen were significantly decreased, an ...201125045311
conformational transitions driven by pyridoxal-5'-phosphate uptake in the psychrophilic serine hydroxymethyltransferase from psychromonas ingrahamii.serine hydroxymethyltransferase (shmt) is a pyridoxal-5'-phosphate (plp)-dependent enzyme belonging to the fold type i superfamily, which catalyzes in vivo the reversible conversion of l-serine and tetrahydropteroylglutamate (h₄pteglu) to glycine and 5,10-methylenetetrahydropteroylglutamate (5,10-ch₂-h₄pteglu). the shmt from the psychrophilic bacterium psychromonas ingrahamii (pishmt) had been recently purified and characterized. this enzyme was shown to display catalytic and stability propertie ...201425044250
the ins and outs of bacterial iron metabolism.iron is a critical nutrient for the growth and survival of most bacterial species. accordingly, much attention has been paid to the mechanisms by which host organisms sequester iron from invading bacteria and how bacteria acquire iron from their environment. however, under oxidative stress conditions such as those encountered within phagocytic cells during the host immune response, iron is released from proteins and can act as a catalyst for fenton chemistry to produce cytotoxic reactive oxygen ...201425040830
decoration of outer membrane vesicles with multiple antigens by using an autotransporter approach.outer membrane vesicles (omvs) are spherical nanoparticles that naturally shed from gram-negative bacteria. they are rich in immunostimulatory proteins and lipopolysaccharide but do not replicate, which increases their safety profile and renders them attractive vaccine vectors. by packaging foreign polypeptides in omvs, specific immune responses can be raised toward heterologous antigens in the context of an intrinsic adjuvant. antigens exposed at the vesicle surface have been suggested to elici ...201425038093
predicting bacterial essential genes using only sequence composition information.essential genes are those genes that are needed by organisms at any time and under any conditions. it is very important for us to identify essential genes from bacterial genomes because of their vital role in synthetic biology and biomedical practices. in this paper, we developed a support vector machine (svm)-based method to predict essential genes of bacterial genomes using only compositional features. these features are all derived from the primary sequences, i.e., nucleotide sequences and pr ...201425036505
salmonella typhimurium with γ-radiation induced h2ax phosphorylation and apoptosis in melanoma.to investigate the combinatorial effects using salmonella and γ-radiation, the salmonella typhimurium infection in combination with γ-radiation was investigated on melanoma. we showed that ros expression and h2ax phosphorylation increased during stress by γ-radiation irrespective of salmonella infection, inducing apoptosis by caspase-3 and bcl2 in tumor cells. in addition, tumor growth was suppressed by this combinatory therapy suggesting candidates for radiation therapy against melanoma.201425036139
novobiocin sensitivity of salmonella typhimurium dam and/or seqa mutants.this study was carried out to determine the effects of novobiocin, a gyrase inhibitor, on the growth, survival, motility and whole cell proteins of s. typhimurium dam and/or seqa strains. our results showed that the dam and seqa/dam mutants are the most sensitive to novobiocin, compared to wild type and seqa strains. surprisingly, the motility of seqa mutants increased after exposure to novobiocin only in stationary phase cells. all the other strains showed a significant decrease in their motili ...201425033662
the mechanisms of m-cell differentiation.intestinal m (microfold or membranous) cells are an enigmatic lineage of intestinal epithelial cells that initiate mucosal immune responses through the uptake and transcytosis of luminal antigens. due to their rarity, the mechanisms of m-cell function and differentiation are poorly understood. to overcome this problem, experimental strategies to enrich for m-cells have been established. transcriptome analyses have provided valuable insight, especially on the receptors for antigen uptake, and suc ...201425032083
the rcscdb regulatory system plays a crucial role in the protection of salmonella enterica serovar typhimurium against oxidative stress.dps, the most abundant protein during the stationary growth phase, in salmonella enterica is required for resistance to reactive oxygen species produced by the host during infection. it has been reported that in salmonella dps expression is controlled by rpos and fur proteins. however, the regulation and function of dps remain to be resolved. in the present work we demonstrate that activation of the complex rcscdb regulatory system increases dps expression during exponential growth of salmonella ...201425028458
antimicrobial activity of ammodaucus leucotrichus fruit oil from algerian sahara.three fruit oil samples of ammodaucus leucotrichus cosson & durieu from algerian sahara were obtained by hydrodistillation and analyzed by gc(ri), gc-ms and 13c nmr spectroscopy. the main compounds were perillaldehyde (87.0-87.9%) and limonene (7.4-8.2%). the antimicrobial effect of the essential oil was evaluated against bacteria, yeasts and filamentous fungi. high antibacterial activity was observed against escherichia coli, staphylococcus aureus. enterobacter cloaceae, bacillus cereus and sal ...201425026729
[diversity of human salmonella isolates in the south moravian region in 2009-2012].to characterize the diversity of human salmonella isolates from one of the administrative regions of the czech republic in a time horizon of four years using different typing methods.201425025676
xanthium strumarium l. extracts produce dna damage mediated by cytotoxicity in in vitro assays but does not induce micronucleus in mice.xanthium strumarium l. is a member of the asteraceae commonly used in cuba, mainly as diuretic. some toxic properties of this plant have also been reported and, to date, very little is known about its genotoxic properties. the present work aims was to evaluate the potential cytotoxic and genotoxic risk of whole extract from xanthium strumarium l. whole extract of aerial parts. no positive response was observed in a battery of four salmonella typhimurium strains, when exposed to concentrations up ...201425025061
extra-intestinal salmonellosis in a tertiary care center in south india.the present study is a retrospective analysis of a total of 36 cases of bacteriologically proven extra-intestinal salmonellosis, managed at nizam's institute of medical sciences, between 1987 and 2012 (25 years). the extra-intestinal sites involved were the skin, cerebrum, spleen, ovary, synovium, and the skeletal muscle.201425022292
flagellin from marinobacter algicola and vibrio vulnificus activates the innate immune response of gilthead seabream.adjuvants have emerged as the best tools to enhance the efficacy of vaccination. however, the traditional adjuvants used in aquaculture may cause adverse alterations in fish making necessary the development of new adjuvants able to stimulate the immune system and offer strong protection against infectious pathogens with minimal undesirable effects. in this respect, flagellin seems an attractive candidate due to its ability to strongly stimulate the immune response of fish. in the present study, ...201425020195
p22 mediated recombination of frt-sites.flp mediated site specific recombination of frt-sites is frequently used in genetic engineering to excise, insert or invert dna-cassettes in the chromosome. while constructs flanked by frt-sites are generally considered to be stable in the absence of the flp enzyme, we observed that p22 chromosomes exceeding wild-type length tend to lose frt-flanked insertions via flp independent recombination of frt-sites during phage propagation. this spontaneous recombination should be considered when enginee ...201425019493
species differences in bacterial nhaa na+/h+ exchangers.bacteria have adapted their nhaa na(+)/h(+) exchangers responsible for salt homeostasis to their different habitats. we present an electrophysiological and kinetic analysis of nhaa from helicobacter pylori and compare it to the previously investigated exchangers from escherichia coli and salmonella typhimurium. properties of all three transporters are described by a simple model using a single binding site for h(+) and na(+). we show that h.pylori nhaa only has a small acidic shift of its ph-dep ...201425017436
artificial citrate operon and vitreoscilla hemoglobin gene enhanced mineral phosphate solubilizing ability of enterobacter hormaechei dhrss.mineral phosphate solubilization by bacteria is mediated through secretion of organic acids, among which citrate is one of the most effective. to overproduce citrate in bacterial systems, an artificial citrate operon comprising of genes encoding nadh-insensitive citrate synthase of e. coli and salmonella typhimurium sodium-dependent citrate transporter was constructed. in order to improve its mineral phosphate solubilizing (mps) ability, the citrate operon was incorporated into e. hormaechei dhr ...201425016342
[a parotid abscess caused by salmonella typhimurium]. 201425015306
molecular characterization of the na+/h+-antiporter nhaa from salmonella typhimurium.na+/h+ antiporters are integral membrane proteins that are present in almost every cell and in every kingdom of life. they are essential for the regulation of intracellular ph-value, na+-concentration and cell volume. these secondary active transporters exchange sodium ions against protons via an alternating access mechanism, which is not understood in full detail. na+/h+ antiporters show distinct species-specific transport characteristics and regulatory properties that correlate with respective ...201425010413
structural and functional characterization of duf1471 domains of salmonella proteins srfn, ydgh/sssb, and yaho.bacterial species in the enterobacteriaceae typically contain multiple paralogues of a small domain of unknown function (duf1471) from a family of conserved proteins also known as yhcn or bhsa/mcba. proteins containing duf1471 may have a single or three copies of this domain. representatives of this family have been demonstrated to play roles in several cellular processes including stress response, biofilm formation, and pathogenesis. we have conducted nmr and x-ray crystallographic studies of f ...201425010333
time lapse investigation of antibiotic susceptibility using a microfluidic linear gradient 3d culture device.this study reports a novel approach to quantitatively investigate the antibacterial effect of antibiotics on bacteria using a three-dimensional microfluidic culture device. in particular, our approach is suitable for studying the pharmacodynamics effects of antibiotics on bacterial cells temporally and with a continuous range of concentrations in a single experiment. the responses of bacterial cells to a linear concentration gradient of antibiotics were observed using time-lapse photography, by ...201425007721
purification and characterization of a novel lipopeptide from streptomyces amritsarensis sp. nov. active against methicillin-resistant staphylococcus aureus.nowadays antimicrobial lipopeptides are being widely exploited for developing potential therapeutic agents for treating bacterial infections. in the present study, we have purified and characterized an antimicrobial lipopeptide produced by streptomyces amritsarensis sp. nov. (= mtcc 11845(t) = jcm 19660(t)). the lipopeptide was purified using silica gel chromatography, size exclusion chromatography and reverse phase- hplc. the ms/ms analysis of the lipopeptide revealed that it has amino acid seq ...201425006539
selective endothelin-a receptor blockade attenuates endotoxin-induced pulmonary hypertension and pulmonary vascular dysfunction.endothelin-1 is a potent mediator of sepsis-induced pulmonary hypertension (ph). the pulmonary vascular effects of selective blockade of endothelin receptor subtype a (etar) during endotoxemia remain unknown. we hypothesized that selective etar antagonism attenuates endotoxin-induced ph and improves pulmonary artery (pa) vasoreactivity. adult male sprague-dawley rats (250-450 g) received lipopolysaccharide (lps; salmonella typhimurium; 20 mg/kg intraperitoneally) or vehicle 6 hours before hemody ...201425006449
conservation of the low-shear modeled microgravity response in enterobacteriaceae and analysis of the trp genes in this response.low fluid shear force, including that encountered in microgravity models, induces bacterial responses, but the range of bacteria capable of responding to this signal remains poorly characterized. we systematically analyzed a range of gram negative enterobacteriaceae for conservation of the low-shear modeled microgravity (lsmmg) response using phenotypic assays, qpcr, and targeted mutations. our results indicate lsmmg response conservation across enterobacteriacae with potential variance in up- o ...201425006354
recombinant production, crystallization and x-ray crystallographic structure determination of peptidyl-trna hydrolase from salmonella typhimurium.peptidyl-trna hydrolase (pth; ec 3.1.1.29) from the pathogenic bacterium salmonella typhimurium has been cloned, expressed in escherichia coli and crystallized for x-ray analysis. crystals were grown using hanging-drop vapor diffusion against a reservoir solution consisting of 0.03 m citric acid, 0.05 m bis-tris propane, 1% glycerol, 3% sucrose, 25% peg 6000 ph 7.6. crystals were used to obtain the three-dimensional structure of the native protein at 1.6 å resolution. the structure was determine ...201425005080
apoptin towards safe and efficient anticancer therapies.the chicken anemia virus derived protein apoptin harbors cancer-selective cell killing characteristics, essentially based on phosphorylation-mediated nuclear transfer in cancer cells and efficient cytoplasmic degradation in normal cells. here, we describe a growing set of preclinical experiments underlying the promises of the anti-cancer potential of apoptin. various non-replicative oncolytic viral vector systems have revealed the safety and efficacy of apoptin. in addition, apoptin enhanced the ...201425001531
a protocol to infect caenorhabditis elegans with salmonella typhimurium.in the last decade, c. elegans has emerged as an invertebrate organism to study interactions between hosts and pathogens, including the host defense against gram-negative bacterium salmonella typhimurium. salmonella establishes persistent infection in the intestine of c. elegans and results in early death of infected animals. a number of immunity mechanisms have been identified in c. elegans to defend against salmonella infections. autophagy, an evolutionarily conserved lysosomal degradation pat ...201424998902
theoretical study of the molecular properties of dimethylanthracenes as properties for the prediction of their biodegradation and mutagenicity.there is little information available on methyl derivatives of anthracene and their interaction with the enzymes of bacterial consortia that could be found in petroleum sludge. in this study a theoretical investigation of all dimethylanthracenes (dma) isomers and their relation to biodegradation are presented. equilibrium geometries, ionization potentials (ip), electronic affinities (ea), dipole moments and electronic dipole polarizabilities of dma isomers calculated by density functional theory ...201424997911
identification of metabolic pathways essential for fitness of salmonella typhimurium in vivo.bacterial infections remain a threat to human and animal health worldwide, and there is an urgent need to find novel targets for intervention. in the current study we used a computer model of the metabolic network of salmonella enterica serovar typhimurium and identified pairs of reactions (cut sets) predicted to be required for growth in vivo. we termed such cut sets synthetic auxotrophic pairs. we tested whether these would reveal possible combined targets for new antibiotics by analyzing the ...201424992475
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