| palmitoylation state impacts induction of innate and acquired immunity by the salmonella enterica serovar typhimurium msbb mutant. | lipopolysaccharide (lps), composed of lipid a, core, and o-antigen, is a major virulence factor of salmonella enterica serovar typhimurium, with lipid a being a major stimulator to induce the proinflammatory response via the toll-like receptor 4 (tlr4)-md2-cd14 pathway. while salmonella msbb mutants lacking the myristate chain in lipid a were investigated widely as an anticancer vaccine, inclusion of the msbb mutation in a salmonella vaccine to deliver heterologous antigens has not yet been inve ... | 2011 | 21930761 |
| purification and characterization of the acetyl-coa synthetase from mycobacterium tuberculosis. | acetyl-coa (accoa) synthetase (acs) catalyzes the conversion of acetate into accoa, which is involved in many catabolic and anabolic pathways. although this enzyme has been studied for many years in many organisms, the properties of mycobacterium tuberculosis acs and the regulation of its activity remain unknown. here, the putative acs gene of m. tuberculosis h37rv (mt-acs) was expressed as a fusion protein with 6×his-tag on the c-terminus in escherichia coli. the recombinant mt-acs protein was ... | 2011 | 21896569 |
| treatment of raw poultry with nonthermal dielectric barrier discharge plasma to reduce campylobacter jejuni and salmonella enterica. | nonthermal plasma has been shown to be effective in reducing pathogens on the surface of a range of fresh produce products. the research presented here investigated the effectiveness of nonthermal dielectric barrier discharge plasma on salmonella enterica and campylobacter jejuni inoculated onto the surface of boneless skinless chicken breast and chicken thigh with skin. chicken samples were inoculated with antibiotic-resistant strains of s. enterica and c. jejuni at levels of 10(1) to 10(4) cf ... | 2012 | 22221351 |
| evaluation of salmonella enterica type iii secretion system effector proteins as carriers for heterologous vaccine antigens. | live attenuated strains of salmonella enterica have a high potential as carriers of recombinant vaccines. the type iii secretion system (t3ss)-dependent translocation of s. enterica can be deployed for delivery of heterologous antigens to antigen-presenting cells. here we investigated the efficacy of various effector proteins of the salmonella pathogenicity island (spi2)-encoded t3ss for the translocation of model antigens and elicitation of immune responses. the spi2-t3ss effector proteins sifa ... | 2012 | 22252866 |
| nlrc4 inflammasomes in dendritic cells regulate noncognate effector function by memory cd8(+) t cells. | memory t cells exert antigen-independent effector functions, but how these responses are regulated is unclear. we discovered an in vivo link between flagellin-induced nlrc4 inflammasome activation in splenic dendritic cells (dcs) and host protective interferon-γ (ifn-γ) secretion by noncognate memory cd8(+) t cells, which could be activated by salmonella enterica serovar typhimurium, yersinia pseudotuberculosis and pseudomonas aeruginosa. we show that cd8α(+) dcs were particularly efficient at s ... | 2012 | 22231517 |
| application of a mouse ligated peyer’s patch intestinal loop assay to evaluate bacterial uptake by m cells. | the inside of our gut is inhabited with enormous number of commensal bacteria. the mucosal surface of the gastrointestinal tract is continuously exposed to them and occasionally to pathogens. the gut-associated lymphoid tissue (galt) play a key role for induction of the mucosal immune response to these microbes(1, 2). to initiate the mucosal immune response, the mucosal antigens must be transported from the gut lumen across the epithelial barrier into organized lymphoid follicles such as peyer's ... | 2011 | 22215009 |
| the architecture and ppgpp-dependent expression of the primary transcriptome of salmonella typhimurium during invasion gene expression. | abstract: background: invasion of intestinal epithelial cells by salmonella enterica serovar typhimurium (s. typhimurium) requires expression of the extracellular virulence gene expression programme (stex), activation of which is dependent on the signalling molecule guanosine tetraphosphate (ppgpp). recently, next-generation transcriptomics (rna-seq) has revealed the unexpected complexity of bacterial transcriptomes and in this report we use differential rna sequencing (drna-seq) to define the ... | 2012 | 22251276 |
| antimicrobial activity of different copper alloy surfaces against copper resistant and sensitive salmonella enterica. | copper has shown antibacterial effects against foodborne pathogens. the objective of this study was to evaluate the antibacterial activity of copper surfaces on copper resistant and sensitive strains of salmonella enterica. six different copper alloy coupons (60-99.9% copper) were tested along with stainless steel as the control. the coupons were surface inoculated with either s. enteritidis or one of the 3 copper resistant strains, s. typhimurium s9, s19 and s20; stored under various incubation ... | 2012 | 22265316 |
| transcriptome sequencing of salmonella enterica serovar enteritidis under desiccation and starvation stress in peanut oil. | it is well recognized that salmonella can survive long-term starvation and desiccation stresses and contaminate foods that have intermediate to low water activities; however, little is known about the specific molecular mechanisms underlying its survival and persistence in low water activity foods. in this study, we used the rna-seq approach to compare the transcriptomes (27-33 million 36-bp reads per sample) of a salmonella enterica subsp. enteric serovar enteritidis strain atcc baa-1045 after ... | 2012 | 22265317 |
| inhibition of bacterial carbonic anhydrases and zinc proteases: from orphantargets to innovative new antibiotic drugs. | zinc-containing enzymes, such as carbonic anhydrases (cas) and metalloproteases (mps) play critical functions in bacteria, being involved in various steps of their life cycle, which are important for survival, colonization, acquisition of nutrients for growth and proliferation, facilitation of dissemination, invasion and pathogenicity. the development of resistance to many classes of clinically used antibiotics emphasizes the need of new antibacterial drug targets to be explored. there is a weal ... | 2012 | 22214451 |
| the antibiotic resistance characteristics of non-typhoidal salmonella enterica isolated from food-producing animals, retail meat and humans in south east asia. | antimicrobial resistance is a global problem. it is most prevalent in developing countries where infectious diseases remain common, the use of antibiotics in humans and animals is widespread, and the replacement of older antibiotics with new generation antibiotics is not easy due to the high cost. information on antibiotic resistance phenotypes and genotypes of salmonella spp. in food animals and humans in different countries and geographic regions is necessary to combat the spread of resistance ... | 2012 | 22265849 |
| recombinant antibodies encoded by ighv1-69 react with pul32, a phosphoprotein of cytomegalovirus and b-cell superantigen. | leukemia cells from patients with chronic lymphocytic leukemia (cll) express a highly restricted immunoglobulin heavy variable chain (ighv) repertoire, which suggests that a limited set of antigens reacts with leukemic cells. here, we evaluated the reactivity of a panel of different cll recombinant antibodies (rabs) encoded by the most commonly expressed ighv genes with a panel of selected viral and bacterial pathogens. six different cll rabs encoded by ighv1-69 or ighv3-21, but not a cll rab en ... | 2012 | 22234695 |
| general stress sigma factor rpos influences time required to enter the viable but non-culturable state in salmonella enterica. | in stressful conditions, bacteria enter into the viable but non-culturable (vbnc) state; in this state, they are alive but fail to grow on conventional media on which they normally grow and develop into colonies. the molecular basis underlying this state is unknown. we investigated the role of the alternative sigma factor rpos (σ(38) ) in the vbnc induction using salmonella dublin, salmonella oranienburg and salmonella typhimurium lt2. vbnc was induced by osmotic stress in lt2 and oranienburg. d ... | 2012 | 22256797 |
| bio-capture of s. typhimurium from surface water by aptamer for culture-free quantification. | in this study, a dna aptamer was used to bio-capture salmonella enterica serovar typhimurium from surface water collected from highly endemic zone prior to culture-free detection through molecular-beacon based real-time pcr assay targeting inva gene. the assay could detect s. typhimurium cells (1cfu/pcr or 100cfu/ml) selectively captured by serovar specific dna aptamer. the observations indicate that all the water samples (n=40) collected from the river gomti were contaminated by s. typhimurium ... | 2012 | 22226327 |
| electrospun poly(l-lactic acid)-co-poly(ɛ-caprolactone) nanofibres containing silver nanoparticles for skin-tissue engineering. | silver nanoparticles (agnps) and silver ions (ag(+)) show growth-inhibitory activity against microorganisms and have been used for decades as antibacterial agents in various fields. to fabricate a nanofibrous scaffold which is antibacterial against bacteria and non-toxic to cells, we electrospun composite poly(l-lactic acid)-co-poly(ɛ-caprolactone) nanofibres containing silver nanoparticles (pllcl-agnps) with different concentrations (0.25, 0.50 and 0.75 wt%) of silver nitrate (agno(3)) in pllcl ... | 2012 | 22244047 |
| effect of the salmonella pathogenicity island 2 type iii secretion system on salmonella survival in activated chicken macrophage-like hd11 cells. | in order to better identify the role of the salmonella pathogenicity island 2 (spi-2) type iii secretion system (t3ss) in chickens, we used the well-known gentamicin protection assay with activated hd11 cells. hd11 cells are a macrophage-like chicken cell line that can be stimulated with phorbol 12-myristate 13-acetate (pma) to exhibit more macrophage-like morphology and greater production of reactive oxygen species (ros). activated hd11 cells were infected with a wild-type salmonella enterica s ... | 2011 | 22216355 |
| development of a novel in-water vaccination protocol for dna adenine methylase deficient salmonella enterica serovar typhimurium vaccine in adult sheep. | intensive livestock production is associated with an increased incidence of salmonellosis. the risk of infection and the subsequent public health concern is attributed to increased pathogen exposure and disease susceptibility due to multiple stressors experienced by livestock from farm to feedlot. traditional parenteral vaccine methods can further stress susceptible populations and cause carcass damage, adverse reactions, and resultant increased production costs. as a potential means to address ... | 2011 | 22214887 |
| prevalence and antimicrobial susceptibilities of vibrio, salmonella, and aeromonas isolates from various uncooked seafoods in thailand. | uncooked seafood samples were collected from open markets and supermarkets in bangkok, thailand, and were examined for the presence of vibrio, salmonella, and aeromonas species from january to february 2008. from 120 samples, 272 bacterial isolates were identified through biochemical testing. of all sea bass, shrimp, oyster, and blood cockle samples (30 of each) that were processed for culture, 114 (95%) samples had at least one detectable isolate of vibrio, salmonella, or aeromonas, leaving on ... | 2012 | 22221354 |
| erratum to: deletion of glucose-inhibited division (gida) gene alters the morphological and replication characteristics of salmonella enterica serovar typhimurium. | | 2012 | 22234847 |
| high resolution clustering of salmonella enterica serovar montevideo strains using a next-generation sequencing approach. | abstract: background: next-generation sequencing (ngs) is increasingly being used as a molecular epidemiologic tool for discerning ancestry and traceback of the most complicated, difficult to resolve bacterial pathogens. making a linkage between possible food sources and clinical isolates requires distinguishing the suspected pathogen from an environmental background and placing the variation observed into the wider context of variation occurring within a serovar and among other closely related ... | 2012 | 22260654 |
| differences in the early response of hatchlings of different chicken breeding lines to salmonella enterica serovar enteritidis infection. | poultry products are the major source of food-borne salmonella infection in humans. broiler lines selected to be more resistant to salmonella could reduce the transfer of salmonella to humans. to investigate differences in the susceptibility of newly hatched chicks to oral infection with salmonella enterica serovar enteritidis, 3 commercial broiler lines (a, b, and c) were infected immediately after hatch and compared to healthy controls at 0.33, 1, and 2 d postinfection. weight, bacteriological ... | 2012 | 22252347 |
| persistent salmonella enteritidis environmental contamination on layer farms in the context of an implemented national control program with obligatory vaccination. | the aim of this study was to closely examine the salmonella enterica serovar enteritidis environmental contamination on persistently positive layer farms in belgium during successive laying cycles. all of the farms were required to vaccinate their layers under the national control program for salmonella. seven farms with previous or current salmonella enteritidis contamination were monitored during different stages of the laying period and after cleaning and disinfection (cd). environmental samp ... | 2012 | 22252339 |
| oral co-administration of live attenuated salmonella enterica serovar typhimurium expressing chicken interferon-α and interleukin-18 enhances the alleviation of clinical signs caused by respiratory infection with avian influenza virus h9n2. | the combined use of cytokines has shown synergistic and/or additive effects in controlling several viral infections of livestock animals. however, little is known concerning the practical use of chicken cytokine combinations to control avian diseases. here, we investigated the antiviral efficacy of oral co-administration of chicken interferon-α (chifn-α) and chicken interleukin-18 (chil-18) using attenuated salmonella enterica serovar typhimurium in chickens infected with avian influenza virus ( ... | 2011 | 22245401 |
| characterization of the elphis prophage from salmonella enterica serovar enteritidis strain lk5. | phages are a primary driving force behind the evolution of bacterial pathogens by transferring a variety of virulence genes into their hosts. similar to other bacterial genomes, the salmonella enterica serovar enteritidis lk5 genome contains several regions that are homologous to phages. although genomic analyses demonstrated the presence of prophages, it was unable to confirm which phage elements within the genome were viable. genetic markers were used to tag one of the prophages in the genome ... | 2012 | 22247173 |
| survival and growth of foodborne pathogens in minimally processed vegetables at 4 and 15 °c. | we conducted this study to investigate the survival and growth of pathogens on fresh vegetables stored at 4 and 15 °c. vegetables (romaine lettuce, iceberg lettuce, perilla leaves, and sprouts) were inoculated with 4 pathogens (salmonella enterica serovar typhimurium, staphylococcus aureus, listeria monocytogenes, and escherichia coli o157:h7) and stored at 2 different temperatures for different periods of time (3, 6, 9, 12, and 15 d at 4 °c and 1, 2, 3, 5, and 7 d at 15 °c). populations of the ... | 2012 | 22260117 |
| the antimicrobial effects of propolis collected in different regions in the basque country (northern spain). | the antimicrobial activity of 19 propolis extracts prepared in different solvents (ethanol and propylene glycol) (eep/pep), was evaluated against some bacterial and fungal isolates using the agar-well diffusion method. it was verified that all the samples tested showed antimicrobial activity, although results varied considerably between samples. results revealed that both types of propolis extracts showed highly sensitive antimicrobial action against gram-positive bacteria and fungi at a concent ... | 2011 | 22805915 |
| [detection of salmonella and mycobacterium species in seagulls captured in talcahuano, chile]. | salmonella can be isolated from the feces of seagulls. therefore these birds can be a vector for dissemination of this pathogen. | 2011 | 22446658 |
| [epidemiology, microbiology, and outcomes of septicemia in children treated at the charles de gaulle university pediatric hospital in burkina faso]. | the aim of this study is to describe the epidemiological and microbiological characteristics and outcome of children with septicemia at the charles de gaulle university pediatric hospital of ouagadougou to help improve probabilistic antibiotic therapy in this type of infection. this retrospective descriptive study covered all the children from 0 to 15 years old seen over a period of 7 years in any hospital department with suspected bacteriemia and for whom the bacteriology laboratory performed a ... | 2011 | 22407247 |
| antimicrobial and safety properties of lactobacilli isolated from two cameroonian traditional fermented foods. | twenty-one lactobacillus isolates from "sha'a" (a maize - based fermented beverage) and "kossam" (traditionally fermented cow milk) were selected in accordance with their antagonistic activities and tested for their bacteriocinogenic potential as well as safety properties. these isolates were preliminarily identified as lactobacillus plantarum (62%), lactobacillus rhamnosus (24%), lactobacillus fermentum (10%) and lactobacillus coprophilus (4%) based on phenotypic characteristics and rep-pcr gen ... | 2011 | 22396914 |
| multidrug-resistant salmonella enterica serovar panama carrying class 1 integrons is invasive in taiwanese children. | an increase in group d salmonella isolates with high antimicrobial resistant rates is being seen in taiwan. this study aimed to determine the multidrug-resistant (mdr, more than three antibiotics) phenotype, genotype, and the correlation between the presence of class 1 integrons and its invasiveness of salmonella panama and salmonella enteritidis isolated from children. | 2012 | 23660223 |
| the combination of crispr-mvlst and pfge provides increased discriminatory power for differentiating human clinical isolates of salmonella enterica subsp. enterica serovar enteritidis. | salmonella enterica subsp. enterica serovar enteritidis (s. enteritidis) is a major cause of foodborne salmonellosis. rapid, efficient and accurate methods for identification are required to track specific strains of s. enteritidis during outbreaks of human salmonellosis. by exploiting the hypervariable nature of virulence genes and clustered regularly interspaced short palindromic repeats (crisprs), we previously developed a powerful sequence-based subtyping approach, designated crispr-mvlst. t ... | 2012 | 23498194 |
| antimicrobial activity of oregano oil against antibiotic-resistant salmonella enterica on organic leafy greens at varying exposure times and storage temperatures. | the objective of this study was to evaluate the effectiveness of oregano oil on four organic leafy greens (iceberg and romaine lettuces and mature and baby spinaches) inoculated with salmonella newport as a function of treatment exposure times as well as storage temperatures. leaf samples were washed, dip inoculated with s. newport (6-log cfu/ml) and dried. oregano oil was prepared at 0.1, 0.3, and 0.5% concentrations in sterile phosphate buffered saline (pbs). inoculated leaves were immersed in ... | 2012 | 23498188 |
| performance of the aoac use-dilution method with targeted modifications: collaborative study. | the u.s. environmental protection agency (epa), in collaboration with an industry work group, spearheaded a collaborative study designed to further enhance the aoac use-dilution method (udm). based on feedback from laboratories that routinely conduct the udm, improvements to the test culture preparation steps were prioritized. a set of modifications, largely based on culturing the test microbes on agar as specified in the aoac hard surface carrier test method, were evaluated in a five-laboratory ... | 2012 | 23451377 |
| toward integrative genomics study of genetic resistance to salmonella and campylobacter intestinal colonization in fowl. | salmonella enterica serotypes enteritidis and typhimurium and campylobacter jejuni are responsible for most cases of food poisoning in europe. these bacteria do not cause severe disease symptoms in chicken, but they are easily propagated by symptomless chicken carriers which cannot be easily isolated. this animal tolerance is detrimental to food safety. in this particular case, increasing animal's resistance is not sufficient, since some animals considered as resistant are able to carry bacteria ... | 2012 | 23412643 |
| lactic acid bacteria and bifidobacteria attenuate the proinflammatory response in intestinal epithelial cells induced by salmonella enterica serovar typhimurium. | inflammation is a physiological response to infections and tissue injury; however, abnormal immune responses can give rise to chronic inflammation and contribute to disease progression. various dietary components, including probiotic lactic acid bacteria and prebiotics, have the potential to modulate intestinal inflammatory responses. one factor in particular, the chemokine interleukin-8 (il-8, cxcl-8), is one of the major mediators of the inflammatory response. the purpose of this study was to ... | 2012 | 23391223 |
| evaluation of salmonella enterica serovar typhimurium ttss-2 deficient fur mutant as safe live-attenuated vaccine candidate for immunocompromised mice. | salmonella enterica serovar typhimurium has been extensively exploited as live attenuated vaccines (lav) which generally confers better protection than killed or subunit vaccines. however, many lav are limited by their inherent ability to access systemic organs in many of the vaccinated hosts, especially those which are immunocompromised. we evaluated the efficacy of a live-attenuated spi2-deficient (δssav) s. typhimurium vaccine candidate (mt13) that additionally devoids the ferric uptake regul ... | 2012 | 23284865 |
| salmonella typhimurium's transthyretin-like protein is a host-specific factor important in fecal survival in chickens. | the transthyretin-like protein (tlp) from salmonella enterica subspecies i is a periplasmic protein with high level structural similarity to a protein found in mammals and fish. in humans, the protein homologue, transthyretin, binds and carries retinol and thyroxine, and a series of other, unrelated aromatic compounds. here we show that the amino acid sequence of the tlp from different species, subspecies and serovars of the salmonella genus is highly conserved and demonstrate that the tlp gene ... | 2012 | 23284609 |
| characterization of citrobacter sp. line 328 as a source of vi for a vi-crm(197) glycoconjugate vaccine against salmonella typhi. | salmonella enterica serovar typhi is the causative agent of typhoid fever with over 22 million cases and over 200,000 deaths reported annually. a vaccine is much needed for use in young children and the novartis vaccines institute for global health (nvgh) is developing a conjugate vaccine which targets s. typhi vi capsular polysaccharide. | 2012 | 23277501 |
| optimized microbial dna extraction from diarrheic stools. | the detection of enteropathogens in stool specimens increasingly relies on the detection of specific nucleic acid sequences. we observed that such detection was hampered in diarrheic stool specimens and we set-up an improved protocol combining lyophilization of stools prior to a semi-automated dna extraction. | 2012 | 23273000 |
| azithromycin and ciprofloxacin resistance in salmonella bloodstream infections in cambodian adults. | salmonella enterica is a frequent cause of bloodstream infection (bsi) in asia but few data are available from cambodia. we describe salmonella bsi isolates recovered from patients presenting at sihanouk hospital centre of hope, phnom penh, cambodia (july 2007-december 2010). | 2012 | 23272255 |
| sesbania grandiflora leaf extract mediated green synthesis of antibacterial silver nanoparticles against selected human pathogens. | simple, effective and rapid approach for the green synthesis of silver nanoparticles (agnps) using leaf extract of sesbania grandiflora and their in vitro antibacterial activity against selected human pathogens has been demonstrated in the study. various instrumental techniques were adopted to characterize the synthesized agnps viz. uv-vis, ftir, xrd, tem, edx and afm. surface plasmon spectra for agnps are centered at 422 nm with dark brown color. the synthesized agnps were found to be spherical ... | 2012 | 23270884 |
| spontaneous non-rdar mutations increase fitness of salmonella in plants. | proliferation of human enteric pathogens within alternate hosts, like plants, leads to temporal changes in gene expression and also selects for the phenotypic variants of the enterics that are presumed to be more fit within plants. human enteric pathogens recovered from produce-borne outbreaks exhibit peculiar phenotypes, for example many of them do not display the rdar (red dry and rough) phenotype. the non-rdar phenotype results from mutations in cellulose and/or curli synthesis or regulation. ... | 2012 | 23760832 |
| root internalization, transport and in-planta survival of salmonella enterica serovar newport in sweet basil. | it is now acknowledged that food-borne pathogens present in the irrigation water or soil can become associated with crop plants in the field, penetrate internal plant tissues via the root, translocate and survive inside plants. only little information is available concerning interaction between enteric pathogens and plants. the present study evaluated the potential for contamination of the aromatic plant, sweet basil during cultivation, by salmonella enterica serovar newport. root internalizatio ... | 2012 | 23757144 |
| evaluation of the strain variability of salmonella enterica acid and heat resistance. | the inherent acid and heat resistances of 60 salmonella enterica strains were assessed in tryptone soy broth without dextrose acidified to ph 3.0 or heated at 57 °c. a total of 360 inactivation curves were generated. regarding the acid challenge experiments, the inactivation rate (kacid), estimated using the log-linear model, ranged from 0.47 to 3.25 h(-1). a log-linear model with a "survival tail" was used to describe the thermal inactivation of the strains, and the estimated inactivation rate ... | 2012 | 23541192 |
| inactivation of salmonella enterica serovar typhimurium and escherichia coli o157:h7 in peanut butter cracker sandwiches by radio-frequency heating. | a multistate outbreak of salmonella enterica serovar typhimurium recently occurred in the usa, which was traced back to various food products made with contaminated peanut butter. this study was conducted to investigate the efficacy of radio-frequency (rf) heating to inactivate s. typhimurium and escherichia coli o157:h7 in peanut butter cracker sandwiches using creamy and chunky commercial peanut butter and to determine the effect on quality by measuring color changes and sensory evaluation. sa ... | 2012 | 23498191 |
| salmonella enterica serovar typhi in breast abscess: a case report. | | 2012 | 23455830 |
| ramr mutations affecting fluoroquinolone susceptibility in epidemic multidrug-resistant salmonella enterica serovar kentucky st198. | a screening for non-target mutations affecting fluoroquinolone susceptibility was conducted in epidemic multidrug-resistant salmonella enterica serovar kentucky st198. among a panel of representative isolates (n = 27), covering the epidemic, only three showed distinct mutations in ramr resulting in enhanced expression of genes encoding the acrab-tolc efflux system and low increase in ciprofloxacin mic. no mutations were detected in other regulatory regions of this efflux system. ciprofloxacin re ... | 2013 | 23914184 |
| the virulence of salmonella typhimurium in the insect model galleria mellonella is impaired by mutations in endoribonucleases e and iii. | salmonella enterica serovar typhimurium is a gram-negative bacterium able to invade and replicate inside eukaryotic cells. to cope with the host defense mechanisms, the bacterium has to rapidly remodel its transcriptional status. regulatory rnas and ribonucleases are the factors that ultimately control the fate of mrnas and final protein levels in the cell. there is growing evidence of the direct involvement of these factors in bacterial pathogenicity. in this report, we validate the use of gall ... | 2013 | 23913419 |
| infectious diseases in humanized mice. | despite many theoretical incompatibilities between mouse and human cells, mice with reconstituted human immune system components contain nearly all human leukocyte populations. accordingly, several human-tropic pathogens have been investigated in these in vivo models of the human immune system, including viruses such as human immunodeficiency virus (hiv) and epstein barr virus (ebv), as well as bacteria such as mycobacterium tuberculosis (mtb) and salmonella enterica typhi (s. typhi). while thes ... | 2013 | 23913412 |
| evaluation of the immunogenicity of campylobacter jejuni cjaa protein delivered by salmonella enterica sv. typhimurium strain with regulated delayed attenuation in chickens. | campylobacter spp. are regarded as the most common bacterial cause of gastroenteritis worldwide, and consumption of chicken meat contaminated by campylobacter is considered to be one of the most frequent sources of human infection in developed countries. here we evaluated the immunogenicity and protective efficacy of salmonella typhimurium χ9718 producing the campylobacter jejuni cjaa protein as a chicken anti-campylobacter vaccine. in this study chickens were orally immunized with a new generat ... | 2013 | 23913025 |
| on-chip microbial culture for the specific detection of very low levels of bacteria. | microbial culture continues to be the most common protocol for bacterial detection and identification in medicine and agronomics. using this process may take days to identify a specific pathogen for most bacterial strains. surface plasmon resonance (spr) detection is an emerging alternative technology that can be used for the detection of bacteria using protein microarrays although typical limits of detection are in the range of 10(3)-10(6) cfu ml(-1), which is not compatible with most food safe ... | 2013 | 23912527 |
| wksl3, a new biocontrol agent for salmonella enterica serovars enteritidis and typhimurium in foods: characterization, application, sequence analysis, and oral acute toxicity study. | of the salmonella enterica serovars, s. enteritidis and s. typhimurium are responsible for most of the salmonella outbreaks implicated in the consumption of contaminated foods in the republic of korea. because of the widespread occurrence of antimicrobial-resistant salmonella in foods and food processing environments, bacteriophages have recently surfaced as an alternative biocontrol tool. in this study, we isolated a virulent bacteriophage (wksl3) that could specifically infect s. enteritidis, ... | 2013 | 23335772 |
| the structure and regulation of flagella in bacillus subtilis. | bacterial flagellar motility is among the most extensively studied physiological systems in biology, but most research has been restricted to using the highly similar gram-negative species escherichia coli and salmonella enterica. here, we review the recent advances in the study of flagellar structure and regulation of the distantly related and genetically tractable gram-positive bacterium bacillus subtilis. b. subtilis has a thicker layer of peptidoglycan and lacks the outer membrane of the gra ... | 2014 | 25251856 |
| metabolic engineering of salmonella vaccine bacteria to boost human vγ2vδ2 t cell immunity. | human vγ2vδ2 t cells monitor isoprenoid metabolism by recognizing foreign (e)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (hmbpp), a metabolite in the 2-c-methyl-d-erythritol-4-phosphate pathway used by most eubacteria and apicomplexan parasites, and self isopentenyl pyrophosphate, a metabolite in the mevalonate pathway used by humans. whereas microbial infections elicit prolonged expansion of memory vγ2vδ2 t cells, immunization with prenyl pyrophosphates or aminobisphosphonates elicit short-ter ... | 2014 | 24943221 |
| a sequence-based approach for prediction of csra/rsma targets in bacteria with experimental validation in pseudomonas aeruginosa. | csra/rsma homologs are an extensive family of ribonucleic acid (rna)-binding proteins that function as global post-transcriptional regulators controlling important cellular processes such as secondary metabolism, motility, biofilm formation and the production and secretion of virulence factors in diverse bacterial species. while direct messenger rna binding by csra/rsma has been studied in detail for some genes, it is anticipated that there are numerous additional, as yet undiscovered, direct ta ... | 2014 | 24782516 |
| molecular architecture of the bacterial flagellar motor in cells. | the flagellum is one of the most sophisticated self-assembling molecular machines in bacteria. powered by the proton-motive force, the flagellum rapidly rotates in either a clockwise or counterclockwise direction, which ultimately controls bacterial motility and behavior. escherichia coli and salmonella enterica have served as important model systems for extensive genetic, biochemical, and structural analysis of the flagellum, providing unparalleled insights into its structure, function, and gen ... | 2014 | 24697492 |
| poultry body temperature contributes to invasion control through reduced expression of salmonella pathogenicity island 1 genes in salmonella enterica serovars typhimurium and enteritidis. | salmonella enterica serovars typhimurium (s. typhimurium) and enteritidis (s. enteritidis) are foodborne pathogens, and outbreaks are often associated with poultry products. chickens are typically asymptomatic when colonized by these serovars; however, the factors contributing to this observation are uncharacterized. whereas symptomatic mammals have a body temperature between 37°c and 39°c, chickens have a body temperature of 41°c to 42°c. here, in vivo experiments using chicks demonstrated that ... | 2015 | 26386070 |
| the development and evaluation of a loop-mediated isothermal amplification method for the rapid detection of salmonella enterica serovar typhi. | typhoid fever remains a public health threat in many countries. a positive result in traditional culture is a gold-standard for typhoid diagnosis, but this method is time consuming and not sensitive enough for detection of samples containing a low copy number of the target organism. the availability of the loop-mediated isothermal amplification (lamp) assay, which offers high speed and simplicity in detection of specific targets, has vastly improved the diagnosis of numerous infectious diseases. ... | 2015 | 25910059 |
| presence of zoonotic agents in engorged ticks and hedgehog faeces from erinaceus europaeus in (sub) urban areas. | european hedgehogs (erinaceus europaeus) are hosts for ixodes hexagonus and i. ricinus ticks, which are vectors for zoonotic microorganisms. in addition, hedgehogs may carry several enteric zoonoses as well. it is unclear to what extent a presence of pathogens in hedgehogs poses a risk to public health, as information on the presence of zoonotic agents in hedgehogs in urban areas is relatively scarce. | 2015 | 25885888 |
| new role for fda-approved drugs in combating antibiotic-resistant bacteria. | antibiotic resistance in medically relevant bacterial pathogens, coupled with a paucity of novel antimicrobial discoveries, represents a pressing global crisis. traditional drug discovery is an inefficient and costly process; however, systematic screening of food and drug administration (fda)-approved therapeutics for other indications in humans offers a rapid alternative approach. in this study, we screened a library of 780 fda-approved drugs to identify molecules that rendered raw 264.7 murine ... | 2016 | 27067323 |
| salmonella enterica serovar typhimurium utilizes the clppx and lon proteases for optimal fitness in the ceca of chickens. | salmonella enterica serovar typhimurium (s. typhimurium) is a leading cause of salmonellosis. poultry and poultry products are implicated in transmission of salmonella to humans. in 2013, an outbreak of s typhimurium occurred that comprised 39 states within the united states and was associated with backyard flocks of chickens. colonization of the avian host by s typhimurium requires numerous genetic factors encoded within the bacterium. of particular interest are genetic factors induced by alter ... | 2016 | 26994203 |
| neisseria meningitidis translation elongation factor p and its active-site arginine residue are essential for cell viability. | translation elongation factor p (ef-p), a ubiquitous protein over the entire range of bacterial species, rescues ribosomal stalling at consecutive prolines in proteins. in escherichia coli and salmonella enterica, the post-translational β-lysyl modification of lys34 of ef-p is important for the ef-p activity. the β-lysyl ef-p modification pathway is conserved among only 26-28% of bacteria. recently, it was found that the shewanella oneidensis and pseudomonas aeruginosa ef-p proteins, containing ... | 2016 | 26840407 |
| hypothetical protein bb0569 is essential for chemotaxis of the lyme disease spirochete borrelia burgdorferi. | the lyme disease spirochete borrelia burgdorferi has five putative methyl-accepting chemotaxis proteins (mcps). in this report, we provide evidence that a hypothetical protein, bb0569, is essential for the chemotaxis of b. burgdorferi. while bb0569 lacks significant homology to the canonical mcps, it contains a conserved domain (spanning residues 110 to 170) that is often evident in membrane-bound mcps such as tar and tsr of escherichia coli. unlike tar and tsr, bb0569 lacks transmembrane region ... | 2016 | 26644432 |
| analysis of thic variants in the context of the metabolic network of salmonella enterica. | in bacteria, the 4-amino-hydroxymethyl-2-methylpyrimidine (hmp) moiety of thiamine is synthesized from 5-aminoimidazole ribotide (air), a branch point metabolite of purine and thiamine biosynthesis. thic is a member of the radical s-adenosylmethionine (adomet) superfamily and catalyzes the complex chemical rearrangement of air to hmp-p. as reconstituted in vitro, the thic reaction requires adomet, air, and reductant. this study analyzed variants of thic in vivo and in vitro to probe the metaboli ... | 2012 | 22961850 |
| multiplicity of salmonella entry mechanisms, a new paradigm for salmonella pathogenesis. | the salmonella enterica species includes about 2600 diverse serotypes, most of which cause a wide range of food- and water-borne diseases ranging from self-limiting gastroenteritis to typhoid fever in both humans and animals. moreover, some serotypes are restricted to a few animal species, whereas other serotypes are able to infect plants as well as cold- and warm-blooded animals. an essential feature of the pathogenicity of salmonella is its capacity to cross a number of barriers requiring inva ... | 2012 | 23170225 |
| role of host cell-derived amino acids in nutrition of intracellular salmonella enterica. | the facultative intracellular pathogen salmonella enterica resides in a specific membrane-bound compartment termed the salmonella-containing vacuole (scv). despite being segregated from access to metabolites in the host cell cytosol, salmonella is able to efficiently proliferate within the scv. we set out to unravel the nutritional supply of salmonella in the scv with focus on amino acids. we studied the availability of amino acids by the generation of auxotrophic strains for alanine, asparagine ... | 2015 | 26351287 |
| aminoimidazole carboxamide ribotide exerts opposing effects on thiamine synthesis in salmonella enterica. | in salmonella enterica, the thiamine biosynthetic intermediate 5-aminoimidazole ribotide (air) can be synthesized de novo independently of the early purine biosynthetic reactions. this secondary route to air synthesis is dependent on (i) 5-amino-4-imidazolecarboxamide ribotide (aicar) accumulation, (ii) a functional phosphoribosylaminoimidazole-succinocarboxamide (saicar) synthetase (purc; ec 6.3.2.6), and (iii) methionine and lysine in the growth medium. studies presented here show that aicar i ... | 2015 | 26100042 |
| the outer membrane protease pgte of salmonella enterica interferes with the alternative complement pathway by cleaving factors b and h. | the virulence factor pgte is an outer membrane protease (omptin) of the zoonotic pathogen salmonella enterica that causes diseases ranging from gastroenteritis to severe enteric fever. it is surface exposed in bacteria that have a short-chain, i.e., rough lps, as observed e.g., in bacteria residing inside macrophages or just emerging from them. we investigated whether pgte cleaves the complement factors b (b) and h (h), key proteins controlling formation and inactivation of the complement protei ... | 2015 | 25705210 |
| the agricultural antibiotic carbadox induces phage-mediated gene transfer in salmonella. | antibiotics are used for disease therapeutic or preventative effects in humans and animals, as well as for enhanced feed conversion efficiency in livestock. antibiotics can also cause undesirable effects in microbial populations, including selection for antibiotic resistance, enhanced pathogen invasion, and stimulation of horizontal gene transfer. carbadox is a veterinary antibiotic used in the us during the starter phase of swine production for improved feed efficiency and control of swine dyse ... | 2014 | 24575089 |
| first trimester typhoid fever with vertical transmission of salmonella typhi, an intracellular organism. | we report a case in which placental abruption occurred at 16 weeks following first trimester diagnosis and treatment for typhoid fever. unexpectedly salmonella enterica serovar typhi (s. typhi) was found in fetal tissues at autopsy. using information from the murine model of typhoid fever in pregnancy, we draw parallels between s. typhi and l. monocytogenes to develop a plausible hypothesis to explain how this organism was able to cross the placenta in the first trimester to cause abruption, inf ... | 2013 | 24459469 |
| quantification of bacterial indicators and zoonotic pathogens in dairy wastewater ponds. | zoonotic pathogens in land-applied dairy wastewaters are a potential health risk. the occurrence and abundance of 10 pathogens and 3 fecal indicators were determined by quantitative real-time pcr (qpcr) in samples from 30 dairy wastewaters from southern idaho. samples tested positive for campylobacter jejuni, stx(1)- and eaea-positive escherichia coli, listeria monocytogenes, mycobacterium avium subsp. paratuberculosis, and salmonella enterica, with mean recoveries of genomic dna corresponding t ... | 2012 | 22983964 |
| humanized tlr4/md-2 mice reveal lps recognition differentially impacts susceptibility to yersinia pestis and salmonella enterica. | although lipopolysaccharide (lps) stimulation through the toll-like receptor (tlr)-4/md-2 receptor complex activates host defense against gram-negative bacterial pathogens, how species-specific differences in lps recognition impact host defense remains undefined. herein, we establish how temperature dependent shifts in the lipid a of yersinia pestis lps that differentially impact recognition by mouse versus human tlr4/md-2 dictate infection susceptibility. when grown at 37°c, y. pestis lps is hy ... | 2012 | 23071439 |
| phosphate groups of lipid a are essential for salmonella enterica serovar typhimurium virulence and affect innate and adaptive immunity. | lipid a is a key component of the outer membrane of gram-negative bacteria and stimulates proinflammatory responses via the toll-like receptor 4 (tlr4)-md2-cd14 pathway. its endotoxic activity depends on the number and length of acyl chains and its phosphorylation state. in salmonella enterica serovar typhimurium, removal of the secondary laurate or myristate chain in lipid a results in bacterial attenuation and growth defects in vitro. however, the roles of the two lipid a phosphate groups in b ... | 2012 | 22753374 |
| detection of zoonotic pathogens and characterization of novel viruses carried by commensal rattus norvegicus in new york city. | norway rats (rattus norvegicus) are globally distributed and concentrate in urban environments, where they live and feed in closer proximity to human populations than most other mammals. despite the potential role of rats as reservoirs of zoonotic diseases, the microbial diversity present in urban rat populations remains unexplored. in this study, we used targeted molecular assays to detect known bacterial, viral, and protozoan human pathogens and unbiased high-throughput sequencing to identify ... | 2014 | 25316698 |
| hospital-based surveillance for infectious etiologies among patients with acute febrile illness in georgia, 2008-2011. | information on the infectious causes of undifferentiated acute febrile illness (afi) in georgia is essential for effective treatment and prevention. in may 2008, a hospital-based afi surveillance was initiated at six hospitals in georgia. patients aged ≥ 4 years with fever ≥ 38°c for ≥ 48 hours were eligible for surveillance. blood culture and serologic testing were conducted for leptospira spp., brucella spp., west nile virus (wnv), crimean-congo hemorrhagic fever virus, coxiella burnetii, tick ... | 2016 | 26438032 |
| posttranslational modification of flagellin flab in shewanella oneidensis. | shewanella oneidensis is a highly motile organism by virtue of a polar, glycosylated flagellum composed of flagellins flaa and flab. in this study, the functional flagellin flab was isolated and analyzed with nano-liquid chromatography-mass spectrometry (ms) and tandem ms. in combination with the mutational analysis, we propose that the flab flagellin protein from s. oneidensis is modified at five serine residues with a series of novel o-linked posttranslational modifications (ptms) that differ ... | 2013 | 23543712 |
| bacterial flagella: twist and stick, or dodge across the kingdoms. | the flagellum organelle is an intricate multiprotein assembly best known for its rotational propulsion of bacteria. however, recent studies have expanded our knowledge of other functions in pathogenic contexts, particularly adherence and immune modulation, e.g., for salmonella enterica, campylobacter jejuni, pseudomonas aeruginosa, and escherichia coli. flagella-mediated adherence is important in host colonisation for several plant and animal pathogens, but the specific interactions that promote ... | 2015 | 25590430 |
| la35 poultry fecal marker persistence is correlated with that of indicators and pathogens in environmental waters. | disposal of fecally contaminated poultry litter by land application can deliver pathogens and fecal indicator bacteria (fib) into receiving waters via runoff. while water quality is regulated by fib enumeration, fib testing provides inadequate information about contamination source and health risk. this microbial source tracking (mst) study compared the persistence of the brevibacterium sp. strain la35 16s rrna gene (marker) for poultry litter with that of pathogens and fib under outdoor, enviro ... | 2015 | 25934617 |
| persistence and potential viable but non-culturable state of pathogenic bacteria during storage of digestates from agricultural biogas plants. | despite the development of on-farm anaerobic digestion as a process for making profitable use of animal by-products, factors leading to the inactivation of pathogenic bacteria during storage of digestates remain poorly described. here, a microcosm approach was used to evaluate the persistence of three pathogenic bacteria (salmonella enterica derby, campylobacter coli and listeria monocytogenes) in digestates from farms, stored for later land spreading. nine samples, including raw digestates, liq ... | 2016 | 27695451 |
| subtyping of salmonella enterica subspecies i using single-nucleotide polymorphisms in adenylate cyclase. | methods to rapidly identify serotypes of salmonella enterica subspecies i are of vital importance for protecting the safety of food. to supplement the serotyping method dkgb-linked intergenic sequence ribotyping (isr), single-nucleotide polymorphisms were characterized within adenylate cyclase (cyaa). the national center for biotechnology information (ncbi) database had 378 cyaa sequences from s. enterica subspecies i, which included 42 unique dna sequences and 19 different amino acid sequences. ... | 2016 | 27035032 |
| l-asparaginase ii produced by salmonella typhimurium inhibits t cell responses and mediates virulence. | salmonella enterica serovar typhimurium avoids clearance by the host immune system by suppressing t cell responses; however, the mechanisms that mediate this immunosuppression remain unknown. we show that s. typhimurium inhibit t cell responses by producing l-asparaginase ii, which catalyzes the hydrolysis of l-asparagine to aspartic acid and ammonia. l-asparaginase ii is necessary and sufficient to suppress t cell blastogenesis, cytokine production, and proliferation and to downmodulate express ... | 2012 | 23245323 |
| description of a putative oligosaccharyl:s-layer protein transferase from the tyrosine o-glycosylation system of paenibacillus alvei ccm 2051(t). | surface (s)-layer proteins are model systems for studying protein glycosylation in bacteria and simultaneously hold promises for the design of novel, glyco-functionalized modules for nanobiotechnology due to their 2d self-assembly capability. understanding the mechanism governing s-layer glycan biosynthesis in the gram-positive bacterium paenibacillus alvei ccm 2051(t) is necessary for the tailored glyco-functionalization of its s-layer. here, the putative oligosaccharyl:s-layer protein transfer ... | 2012 | 25893145 |
| the campylobacter jejuni dps homologue is important for in vitro biofilm formation and cecal colonization of poultry and may serve as a protective antigen for vaccination. | in this work, we investigated the campylobacter jejuni dps (dna binding protein from starved cells) gene for a role in biofilm formation and cecal colonization in poultry. in vitro biofilm formation assays were conducted with stationary-phase cells in cell culture plates under microaerophilic conditions. these studies demonstrated a significant (>50%) reduction in biofilm formation by the c. jejuni dps mutant compared to that by the wild-type strain. studies in poultry also demonstrated the impo ... | 2012 | 22787197 |
| salmonella "sops" up a preferred electron receptor in the inflamed intestine. | the microbiota of the mammalian intestinal tract represents a formidable barrier to colonization by pathogens. to overcome this resistance to colonization, bacterial pathogens use virulence factors to induce intestinal inflammation, which liberates nutrients for selective use by the infecting microbe. studies of salmonella enterica serovar typhimurium (s. typhimurium) infection in a streptomycin-treated mouse colitis model show how virulence factor-induced inflammation can produce nutrients used ... | 2012 | 22893385 |
| multilocus sequence typing as a replacement for serotyping in salmonella enterica. | salmonella enterica subspecies enterica is traditionally subdivided into serovars by serological and nutritional characteristics. we used multilocus sequence typing (mlst) to assign 4,257 isolates from 554 serovars to 1092 sequence types (sts). the majority of the isolates and many sts were grouped into 138 genetically closely related clusters called eburstgroups (ebgs). many ebgs correspond to a serovar, for example most typhimurium are in ebg1 and most enteritidis are in ebg4, but many ebgs co ... | 2012 | 22737074 |
| phage-mediated acquisition of a type iii secreted effector protein boosts growth of salmonella by nitrate respiration. | information on how emerging pathogens can invade and persist and spread within host populations remains sparse. in the 1980s, a multidrug-resistant salmonella enterica serotype typhimurium clone lysogenized by a bacteriophage carrying the sope virulence gene caused an epidemic among cattle and humans in europe. here we show that phage-mediated horizontal transfer of the sope gene enhances the production of host-derived nitrate, an energetically highly valuable electron acceptor, in a mouse colit ... | 2012 | 22691391 |
| signature tagged mutagenesis in the functional genetic analysis of gastrointestinal pathogens. | signature tagged mutagenesis is a genetic approach that was developed to identify novel bacterial virulence factors. it is a negative selection method in which unique identification tags allow analysis of pools of mutants in mixed populations. the approach is particularly well suited to functional genetic analysis of the gastrointestinal phase of infection in foodborne pathogens and has the capacity to guide the development of novel vaccines and therapeutics. in this review we outline the techni ... | 2012 | 22555467 |
| storing drinking-water in copper pots kills contaminating diarrhoeagenic bacteria. | microbially-unsafe water is still a major concern in most developing countries. although many water-purification methods exist, these are expensive and beyond the reach of many people, especially in rural areas. ayurveda recommends the use of copper for storing drinking-water. therefore, the objective of this study was to evaluate the effect of copper pot on microbially-contaminated drinking-water. the antibacterial effect of copper pot against important diarrhoeagenic bacteria, including vibrio ... | 2012 | 22524115 |
| surface-immobilization of chromatographically purified bacteriophages for the optimized capture of bacteria. | bacteriophages offer interesting alternatives to antibodies for the specific capture and detection of pathogenic bacteria onto biosensing surfaces. procedures for the optimal chemical immobilization of lytic bacteriophages onto surfaces are presented. more specifically, the removal of lysate contaminants from bacteriophage suspensions by size exclusion chromatography significantly increases the resultant planar surface density of immobilized bacteriophages. e. coli t4 and salmonella enterica ser ... | 2012 | 22666653 |
| competition for zinc binding in the host-pathogen interaction. | due to its favorable chemical properties, zinc is used as a structural or catalytic cofactor in a very large number of proteins. despite the apparent abundance of this metal in all cell types, the intracellular pool of loosely bound zinc ions available for biological exchanges is in the picomolar range and nearly all zinc is tightly bound to proteins. in addition, to limit bacterial growth, some zinc-sequestering proteins are produced by eukaryotic hosts in response to infections. therefore, to ... | 2013 | 24400228 |
| fitness benefits in fluoroquinolone-resistant salmonella typhi in the absence of antimicrobial pressure. | fluoroquinolones (fq) are the recommended antimicrobial treatment for typhoid, a severe systemic infection caused by the bacterium salmonella enterica serovar typhi. fq-resistance mutations in s. typhi have become common, hindering treatment and control efforts. using in vitro competition experiments, we assayed the fitness of eleven isogenic s. typhi strains with resistance mutations in the fq target genes, gyra and parc. in the absence of antimicrobial pressure, 6 out of 11 mutants carried a s ... | 2013 | 24327559 |
| salmonella pathogenicity and host adaptation in chicken-associated serovars. | enteric pathogens such as salmonella enterica cause significant morbidity and mortality. s. enterica serovars are a diverse group of pathogens that have evolved to survive in a wide range of environments and across multiple hosts. s. enterica serovars such as s. typhi, s. dublin, and s. gallinarum have a restricted host range, in which they are typically associated with one or a few host species, while s. enteritidis and s. typhimurium have broad host ranges. this review examines how s. enterica ... | 2013 | 24296573 |
| the abc-type efflux pump macab protects salmonella enterica serovar typhimurium from oxidative stress. | multidrug efflux pumps are integral membrane proteins known to actively excrete antibiotics. the macrolide-specific pump macab, the only abc-type drug efflux pump in salmonella, has previously been linked to virulence in mice. the molecular mechanism of this link between macab and infection is unclear. we demonstrate that macab plays a role in the detoxification of reactive oxygen species (ros), compounds that salmonellae are exposed to at various stages of infection. macab is induced upon expos ... | 2013 | 24169575 |
| sandwich assay for mixed-sequence recognition of double-stranded dna: invader-based detection of targets specific to foodborne pathogens. | a 96-well plate sandwich assay based on invader capture/signalling probes is used to recognize 28-mer mixed-sequence dsdna targets specific to salmonella enterica, campylobacter jejuni, escherichia coli. targets are detected down to 20-55 pm concentration with excellent binding specificity. | 2013 | 24036937 |
| the mucin muc2 limits pathogen burdens and epithelial barrier dysfunction during salmonella enterica serovar typhimurium colitis. | salmonella enterica serovar typhimurium is a model organism used to explore the virulence strategies underlying salmonella pathogenesis. although intestinal mucus is the first line of defense in the intestine, its role in protection against salmonella is still unclear. the intestinal mucus layer is composed primarily of the muc2 mucin, a heavily o-glycosylated glycoprotein. the core 3-derived o-glycans of muc2 are synthesized by core 3 β1,3-n-acetylglucosaminyltransferase (c3gnt). mice lacking t ... | 2013 | 23876803 |
| survey of culture, goldengate assay, universal biosensor assay, and 16s rrna gene sequencing as alternative methods of bacterial pathogen detection. | cultivation-based assays combined with pcr or enzyme-linked immunosorbent assay (elisa)-based methods for finding virulence factors are standard methods for detecting bacterial pathogens in stools; however, with emerging molecular technologies, new methods have become available. the aim of this study was to compare four distinct detection technologies for the identification of pathogens in stools from children under 5 years of age in the gambia, mali, kenya, and bangladesh. the children were ide ... | 2013 | 23884998 |
| structure and function of the salmonella typhi chimaeric a(2)b(5) typhoid toxin. | salmonella enterica serovar typhi (s. typhi) differs from most other salmonellae in that it causes a life-threatening systemic infection known as typhoid fever. the molecular bases for its unique clinical presentation are unknown. here we find that the systemic administration of typhoid toxin, a unique virulence factor of s. typhi, reproduces many of the acute symptoms of typhoid fever in an animal model. we identify specific carbohydrate moieties on specific surface glycoproteins that serve as ... | 2013 | 23842500 |
| igg subclass antibodies to human and bacterial hsp60 are not associated with disease activity and progression over time in axial spondyloarthritis. | spondyloarthritis (spa), an interrelated group of rheumatic diseases, has been suggested to be triggered by bacterial infections prior to the development of an autoimmune response that causes inflammation of the spinal and peripheral joints. because human heat shock protein 60 (hsp60), recently renamed hspd1, and bacterial hsp60 are highly homologous, immunological cross-reactivity has been proposed as a mechanism of disease initiation. however, previous investigations of the humoral immune resp ... | 2013 | 23705835 |
| genetic mechanisms of antimicrobial resistance identified in salmonella enterica, escherichia coli, and enteroccocus spp. isolated from u.s. food animals. | the prevalence of antimicrobial resistance (ar) in bacteria isolated from u.s. food animals has increased over the last several decades as have concerns of ar foodborne zoonotic human infections. resistance mechanisms identified in u.s. animal isolates of salmonella enterica included resistance to aminoglycosides (e.g., alleles of aacc, aada, aadb, ant, apha, and strab), β-lactams (e.g., bla cmy-2, tem-1, pse-1), chloramphenicol (e.g., flor, cmla, cat1, cat2), folate pathway inhibitors (e.g., al ... | 2013 | 23734150 |
| salmonella uses energy taxis to benefit from intestinal inflammation. | chemotaxis enhances the fitness of salmonella enterica serotype typhimurium (s. typhimurium) during colitis. however, the chemotaxis receptors conferring this fitness advantage and their cognate signals generated during inflammation remain unknown. here we identify respiratory electron acceptors that are generated in the intestinal lumen as by-products of the host inflammatory response as in vivo signals for methyl-accepting chemotaxis proteins (mcps). three mcps, including trg, tsr and aer, enh ... | 2013 | 23637594 |