| typhoid fever: narrowing therapeutic options in india. | typhoid fever remains an important public health problem in india. one thousand four hundred fifty-eight blood cultures were screened, 178 grew out salmonella enterica serovar typhi. on agar dilution minimum inhibitory concentration (mic) testing, 0.6% of the isolates were resistant to ciprofloxacin, 2% to cefotaxime and 1% to cefepime. nalidixic acid resistance was observed in 51% isolates, of which 98.9% had decreased susceptibility (mic > or = 0.125-4 microg/ml) to ciprofloxacin. one strain o ... | 2006 | 17333772 |
| neonatal sepsis caused by salmonella enterica serovar weltevreden. | salmonella enterica serovar weltevreden is an uncommon cause of gastroenteritis occurring worldwide. for the first time, we report 2 cases of neonatal sepsis caused by s. weltevreden from hubli, india. in the first case, the neonate had features of septicemia and s. weltevreden was isolated from a blood culture. the other neonate had omplalitis and clinical features of septicemia. s. enterica serovar weltevreden was isolated from the umbilical swab culture of this neonate. even though extensive ... | 2006 | 17333773 |
| tbk1 protects vacuolar integrity during intracellular bacterial infection. | tank-binding kinase-1 (tbk1) is an integral component of type i interferon induction by microbial infection. the importance of tbk1 and type i interferon in antiviral immunity is well established, but the function of tbk1 in bacterial infection is unclear. upon infection of murine embryonic fibroblasts with salmonella enterica serovar typhimurium (salmonella), more extensive bacterial proliferation was observed in tbk1(-/-) than tbk1(+/+) cells. tbk1 kinase activity was required for restriction ... | 2007 | 17335348 |
| [presternal abscess due to salmonella enterica serovar enteritidis]. | | 2007 | 17335709 |
| phenotypic and genetic characterization of salmonella enterica subsp. enterica serovar typhimurium isolated from pigs in rio grande do sul, brazil. | this study aimed to investigate the relatedness of porcine salmonella enterica subsp. enterica (s.) serovar typhimurium strains isolated in southern brazil. sixty-six isolates from pigs belonging to three commercial companies were submitted to phage typing, xbai-macrorestriction (pfge), is200 hybridization, rep-pcr, antimicrobial susceptibility testing, and pcr assay targeting the spvr region. all strains presented a unique rep-pcr pattern and 63 strains had a common is200 profile. one pulse-typ ... | 2007 | 17336354 |
| porcine differential gene expression in response to salmonella enterica serovars choleraesuis and typhimurium. | an investigation of the porcine response to gastrointestinal infection with salmonella enterica serovars choleraesuis (narrow host range) and typhimurium (broad host range) revealed markedly different transcriptional profiles. seven genes identified by suppression subtractive hybridization as up-regulated in the mesenteric lymph nodes at 24h (h) post-inoculation (p.i.) in serovar choleraesuis-infected pigs (arpc2, cct7, hsph1, lcp1, ptma, sdcbp, vcp) and three genes in serovar typhimurium-infect ... | 2007 | 17337057 |
| multiple environmental stress tests show no common phenotypes shared among contemporary epidemic strains of salmonella enterica. | phenotypic traits of coexisting epidemic and nonepidemic strains of salmonella enterica serovars typhimurium and newport were compared. different stress conditions were relatively more or less favorable for the epidemic strains. transcriptional analysis identified specific upregulated genes during defined stress conditions, but there were no common traits shared by epidemic serovars. | 2007 | 17337548 |
| bactericidal activity of normal bovine serum (nbs) directed against some enterobacteriaceae with sialic acid-containing lipopolysaccharides (lps) as a component of cell wall. | the sensitivity of bacteria to the bactericidal activity of serum depends on the structure and organization of the bacterial outer membrane. sialic acid has been found in the o-specific region of bacterial lipopolysaccharide (lps) and it plays an essential role in protecting gram-negative bacteria against the bactericidal activity of human and animal serum. the susceptibility of gram-negative bacilli with sialic acid-containing lps to the bactericidal action of normal bovine serum (nbs) was dete ... | 2006 | 17338268 |
| in vivo and in vitro analyses of single-amino acid variants of the salmonella enterica phosphotransacetylase enzyme provide insights into the function of its n-terminal domain. | the function of the n-terminal domain ( approximately 350 residues) of the pta (phosphotransacetylase) enzyme of salmonella enterica is unclear. results from in vivo genetic and in vitro studies suggest that the n-terminal domain of pta is a sensor for nadh and pyruvate. we isolated 10 single-amino acid variants of pta that, unlike the wild-type protein, supported growth of a strain of s. enterica devoid of acs (acetyl-coa synthetase; amp-forming) activity on 10 mm acetate. all mutations were ma ... | 2007 | 17339319 |
| effects of nitrate or nitro supplementation, with or without added chlorate, on salmonella enterica serovar typhimurium and escherichia coli in swine feces. | the effects of coincubating the active agent of an experimental chlorate product with nitrate or select nitro compounds, possible inducers and competing substrates for the targeted respiratory nitrate reductase, on concentrations of experimentally inoculated salmonella enterica serovar typhimurium and indigenous escherichia coli were determined. studies were completed in swine fecal suspensions as a prelude to the administration of these inhibitors to pigs. results confirmed the bactericidal eff ... | 2007 | 17340863 |
| characterization of escherichia coli mg1655 grown in a low-shear modeled microgravity environment. | extra-cellular shear force is an important environmental parameter that is significant both medically and in the space environment. escherichia coli cells grown in a low-shear modeled microgravity (lsmmg) environment produced in a high aspect rotating vessel (harv) were subjected to transcriptional and physiological analysis. | 2007 | 17343762 |
| the potential salmonella aroa- vaccine strain is safe and effective in young balb/c mice. | due to the increased susceptibility of neonates to pathogens including those with mutations, the use of live vaccine strategies in the human population may present a potential risk to the young. | 2007 | 17344661 |
| the chicken host peptides, gallinacins 4, 7, and 9 have antimicrobial activity against salmonella serovars. | the gallinacin genes clustered on chromosome 3 of the chicken (gallus gallus domesticus) genome encode a group of cationic antimicrobial peptides characteristic of the beta-defensins. in this study, gallinacins 4, 7, and 9, all predicted to contain the conserved pattern of cysteines typical of beta-defensins but differing in their charge and hydrophobicity, were characterised for their in vivo gene expression patterns and in vitro antimicrobial activities against salmonella serovars. reverse-tra ... | 2007 | 17346671 |
| mart activates expression of the misl autotransporter protein of salmonella enterica serotype typhimurium. | misl is a salmonella enterica serotype typhimurium fibronectin binding protein whose expression is induced during infection of mice. t-pop transposon mutagenesis identified mart as a positive regulatory element controlling expression of a misl::laczya transcriptional fusion. gel shift analysis identified mart as a transcriptional activator of the misl promoter. | 2007 | 17351045 |
| isolation of transposon insertions. | transposon insertions in and near a gene of interest facilitate the genetic characterization of a gene in vivo. this chapter is dedicated to describing the isolation of mini-tn10 insertions in any desired nonessential gene in salmonella enterica, as well as the isolation of mini-tn10 insertions near particular genes. the protocols describe use of a tetracycline-resistant tn10 derivative, but similar approaches can be used for derivatives resistant to other antibiotics. in addition, these approac ... | 2007 | 17352913 |
| generation of deletions and duplications using transposons as portable regions of homology with emphasis on mud and tn10 transposons. | in bacteria complementation and dominance testing requires the establishment of a diploid state for the gene of interest. in addition, it is often desirable to characterize reporter fusion constructs in strains with both the reporter fusion and an intact gene copy present in single copy. transposons provide portable regions of homology to facilitate construction of targeted chromosomal rearrangements such as deletions and duplications. the properties of the large mud transposons, muda and mudb a ... | 2007 | 17352915 |
| recombineering: in vivo genetic engineering in e. coli, s. enterica, and beyond. | "recombineering," in vivo genetic engineering with short dna homologies, is changing how constructs are made. the methods are simple, precise, efficient, rapid, and inexpensive. complicated genetic constructs that can be difficult or even impossible to make with in vitro genetic engineering can be created in days with recombineering. dna molecules that are too large to manipulate with classical techniques are amenable to recombineering. this technology utilizes the phage lambda homologous recomb ... | 2007 | 17352923 |
| lambda-red genetic engineering in salmonella enterica serovar typhimurium. | the use of the recombination system from bacteriophage lambda, lambda-red, allows for pcr-generated fragments to be targeted to specific chromosomal locations in sequenced genomes. a minimal region of homology of 30 to 50 bases flanking the fragment to be inserted is all that is required for targeted mutagenesis. procedures for creating specific insertions, deletions, and site-directed changes are described. | 2007 | 17352924 |
| complement receptor 3 and toll-like receptor 4 act sequentially in uptake and intracellular killing of unopsonized salmonella enterica serovar typhimurium by human neutrophils. | the uptake and subsequent killing of salmonella enterica serovar typhimurium by human neutrophils was studied. in particular, two pattern recognition receptors, complement receptor 3 (cr3) and toll-like receptor 4 (tlr4), were found to be essential for the efficient uptake and activation, respectively, of the nadph oxidase. the uptake of salmonella was almost completely inhibited by various monoclonal antibodies against cr3, and neutrophils from a patient with leukocyte adhesion deficiency type ... | 2007 | 17353285 |
| pathotyping of salmonella enterica by analysis of single-nucleotide polymorphisms in cyaa and flanking 23s ribosomal sequences. | the egg-contaminating phenotype of salmonella enterica serotype enteritidis was linked to single-nucleotide polymorphisms (snps) occurring in cyaa, which encodes adenylate cyclase that produces camp and pyrophosphate from atp. ribotyping indicated that snps in cyaa were linked to polymorphisms occurring in the rrlc and rrla 23s ribosomal subunits. phylogenetic analysis of cyaa discriminated between salmonella enterica serotypes and within serotype enteritidis. serotypes typhimurium, heidelberg a ... | 2007 | 17359275 |
| intranasal immunization with heterologously expressed polysaccharide protects against multiple pseudomonas aeruginosa infections. | surface-expressed bacterial polysaccharides are often immunodominant, protective antigens. however, these antigens are chemically and serologically highly heterogeneous, and conjugation to protein carriers is often necessary to enhance their immunogenicity. here we show the efficacy of intranasal immunization of mice with attenuated salmonella enterica serovar typhimurium expressing the o antigen portion of pseudomonas aeruginosa lipopolysaccharide. p. aeruginosa is an ideal model system because ... | 2007 | 17360574 |
| ssel, a salmonella deubiquitinase required for macrophage killing and virulence. | expression of the salmonella enterica serovar typhimurium pathogenicity island 2 (spi-2) type iii secretion system is controlled by the two-component regulatory system ssra-ssrb. we used a transcriptomic approach to help define the ssra-ssrb regulon. we identified a gene encoding an uncharacterized effector (ssel) whose translocation into host cells depends on the spi-2 secretion system. ssel has similarities to cysteine proteases with deubiquitinating activity. a gst-ssel fusion protein specifi ... | 2007 | 17360673 |
| salmonella infections: immune and non-immune protection with vaccines. | salmonella enterica in poultry remains a major political issue. s. enterica serovar enteritidis, particularly, remains a world-wide problem. control in poultry by immunity, whether acquired or innate, is a possible means of containing the problem. widespread usage of antibiotics has led to the emergence of multiple antibiotic-resistant bacteria. this problem has indicated an increasing requirement for effective vaccines to control this important zoonotic infection. an attempt is made in the pres ... | 2007 | 17364505 |
| identification and molecular characterization of salmonella spp. from unpasteurized orange juices and identification of new serotype salmonella strain s. enterica serovar tempe. | several salmonella enterica serotypes were isolated from unpasteurized orange juice samples analysed as a follow-up to an outbreak in 1999 of s. enterica serotype muenchen in the pacific northwest regions of united states. eleven s. enterica strains were serotyped and identified as s. enterica serotype muenchen (2), s. enterica serotype hidalgo (2), s. enterica serotype alamo (1), s. enterica serotype gaminera (2), s. enterica serotype javiana (2) and a new serotyped strain s. enterica serotype ... | 2007 | 17367687 |
| molecular mechanisms of decreased susceptibility to fluoroquinolones in avian salmonella serovars and their mutants selected during the determination of mutant prevention concentrations. | salmonella enterica isolates of six serovars and mutants obtained during determination of mutant prevention concentrations (mpcs) were investigated for mechanisms of decreased susceptibility to fluoroquinolones. | 2007 | 17369276 |
| quantitative recovery of listeria monocytogenes and select salmonella serotypes from environmental sample media. | environmental sampling has become increasingly important in the food industry for monitoring the presence of specific pathogens such as listeria monocytogenes and salmonella enterica. several microbiological media are available for storage and transport of environmental samples from the processing plant to the test laboratory. in this study, we quantified the survival of l. monocytogenes, s. typhimurium, s. enteritidis, and s. typhi in environmental sampling media over several time and temperatu ... | 2007 | 17373457 |
| clinical and microbiological investigations of typhoid fever in an infectious disease hospital in kuwait. | a retrospective analysis of 135 typhoid cases was conducted to review the clinical, epidemiological and microbiological characteristics of enteric fever cases diagnosed and treated at the infectious diseases hospital, kuwait, from 2002 to 2005. diagnosis of patients was based on clinical features, serology and blood culture. the susceptibility testing of the isolates to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, ceftriaxone, ciprofloxacin and nalidixic acid was performed by the ... | 2007 | 17374897 |
| multiple antimicrobial resistance in plague: an emerging public health risk. | antimicrobial resistance in yersinia pestis is rare, yet constitutes a significant international public health and biodefense threat. in 1995, the first multidrug resistant (mdr) isolate of y. pestis (strain ip275) was identified, and was shown to contain a self-transmissible plasmid (pip1202) that conferred resistance to many of the antimicrobials recommended for plague treatment and prophylaxis. comparative analysis of the dna sequence of y. pestis plasmid pip1202 revealed a near identical inc ... | 2007 | 17375195 |
| general and specific host responses to bacterial infection in peyer's patches: a role for stromelysin-1 (matrix metalloproteinase-3) during salmonella enterica infection. | salmonella enterica serovar typhimurium (s. typhimurium) and yersinia enterocolitica are enteric pathogens capable of colonizing and inducing inflammatory responses in peyer's patches (pps) and mesenteric lymph nodes (mlns). although the tissue colonization pattern is similar between these two pathogens, their pathogenic lifestyles are quite different. for example, while s. typhimurium is primarily an intracellular pathogen, y. enterocolitica survives primarily extracellularly. we determined and ... | 2007 | 17376075 |
| differential expression of virulence-related genes in a salmonella enterica serotype typhimurium luxs mutant in response to autoinducer ai-2 and poultry meat-derived ai-2 inhibitor. | bacterial cells communicate with each other and respond to external stimuli using signal molecules called autoinducers (ais). poultry meat contains inhibitors that apparently interfere with ai-2 signaling. our objective was to understand the expression of salmonella typhimurium genes (using spotted microarrays) in response to ai-2 in the presence, and absence, of poultry meat (pm) derived ai-2 inhibitors. expression of 1136 virulence-related genes in salmonella typhimurium wildtype and its isoge ... | 2007 | 17378703 |
| molecular characterization of salmonella enterica serotype typhi isolates by pulsed-field gel electrophoresis in hong kong, 2000-2004. | to study salmonella enterica serotype typhi by pulsed-field gel electrophoresis in hong kong. | 2007 | 17378707 |
| irradiation d values of salmonella spp. in diced tomatoes dipped in 1% calcium chloride. | outbreaks of salmonellosis have been associated with eating raw domestic tomatoes. in this study, we examined the efficiency of combined irradiation and a 1% calcium chloride dip to reduce the population of salmonella enterica strains on diced tomatoes. tomatoes were contaminated with nalidixic acid-resistant strains of s. hartford, s. montevideo, or a mixture of 5 strains (s. hartford, s. montevideo, s. poona, s. michigan, s. gaminara). we irradiated tomatoes at various doses up to 0.9 kgy from ... | 2007 | 17378712 |
| a pulsed field gel electrophoresis (pfge) study that suggests a major world-wide clone of salmonella enterica serovar enteritidis. | since human infections by salmonella enterica serovar enteritidis (salmonella enteritidis) have been increasing world-wide over the past years and epidemiological studies have implicated the consumption of meat, poultry, eggs and egg products, elucidation of the predominant subtypes for this salmonella spp. is important. in this study, 107 poultry and food isolates of salmonella enteritidis obtained from germany were analyzed by pulsed field gel electrophoresis (pfge), and the subtypes were comp ... | 2007 | 17379345 |
| adhesin-dependent binding and uptake of salmonella enterica serovar typhimurium by dendritic cells. | salmonella enterica serovar typhimurium can be internalized by immature dendritic cells (dcs). the interacting host and bacterial molecules initiating this process remain uncharacterized. the objective of this study was to investigate whether specific fimbriae are involved in the early step of binding and uptake of salmonella by dcs. type 1 fimbriated s. enterica serovar typhimurium or recombinant escherichia coli expressing the type 1 fimbriae showed a significantly greater ability to attach to ... | 2007 | 17379714 |
| agfc and agfe facilitate extracellular thin aggregative fimbriae synthesis in salmonella enteritidis. | salmonella thin aggregative fimbriae (tafi; curli) are important in pathogenesis and biofilm formation; however, less is known of their structure and morphogenesis. in the salmonella agfbac tafi operon, the transcription and role of agfc have been elusive. in this study, agfbac transcripts were detected using a sensitive reverse transcriptase technique. native agfc was not detected using polyclonal antibodies generated against purified hexahistidine-tagged agfc; however, in trans expression reve ... | 2007 | 17379722 |
| identification of novel genes in genomic islands that contribute to salmonella typhimurium replication in macrophages. | salmonella enterica serovar typhimurium (s. typhimurium) survives and proliferates within macrophage cells. a mutant library of strain atcc 14028 based on gene disruption by homologous recombination was screened in order to identify genes that are required for wild-type-like intracellular replication. randomly generated chromosomal fragments from the genome of s. typhimurium were cloned into a temperature-sensitive vector, and approximately 8000 individual mutant clones were obtained by insertio ... | 2007 | 17379730 |
| sipa, sopa, sopb, sopd and sope2 effector proteins of salmonella enterica serovar typhimurium are synthesized at late stages of infection in mice. | salmonella pathogenicity island (spi)-1 is essential for invasion of non-phagocytic cells, whereas spi-2 is required for intracellular survival and proliferation in phagocytes. some spi-1 effectors, however, are induced upon invasion of both phagocytic and non-phagocytic cells, suggesting that they may also be required post-invasion. in the present work, the presence was analysed of sipa, sopa, sopb, sopd and sope2 effector proteins of salmonella enterica serovar typhimurium in vitro and in vivo ... | 2007 | 17379731 |
| a mg2+-responding rna that controls the expression of a mg2+ transporter. | mg2+ is the most abundant divalent cation in biological systems. it is required for atp-mediated enzymatic reactions and as a stabilizer of ribosomes and membranes. the enteric bacterium salmonella enterica serovar typhimurium harbors three mg2+ transporters and a regulatory system-termed phop/phoq-whose activity is regulated by the extracytoplasmic levels of mg2+. we have determined that expression of the phop-activated mg2+ transporter mgta is also controlled by its 5'-untranslated region (5'u ... | 2006 | 17381304 |
| experimental infection of salmonella enteritidis by the poultry red mite, dermanyssus gallinae. | dermanyssus gallinae is an important ectoparasite of laying hens in europe and it is suspected of being a vector of pathogens. we carried out an in vitro study to evaluate the role of d. gallinae as a vector of salmonella enterica subsp. enterica serotype enteritidis. two means of infecting the mite were tested: through the blood meal and after cuticular contact. mites became carriers of salmonella immediately after the infection with 29% and 53%, respectively, for oral route and cuticular conta ... | 2007 | 17382475 |
| multidrug-resistant salmonella enterica serovar paratyphi a harbors inchi1 plasmids similar to those found in serovar typhi. | salmonella enterica serovars typhi and paratyphi a cause systemic infections in humans which are referred to as enteric fever. multidrug-resistant (mdr) serovar typhi isolates emerged in the 1980s, and in recent years mdr serovar paratyphi a infections have become established as a significant problem across asia. mdr in serovar typhi is almost invariably associated with inchi1 plasmids, but the genetic basis of mdr in serovar paratyphi a has remained predominantly undefined. the dna sequence of ... | 2007 | 17384186 |
| assessment and interpretation of bacterial viability by using the live/dead baclight kit in combination with flow cytometry. | the commercially available live/dead baclight kit is enjoying increased popularity among researchers in various fields of microbiology. its use in combination with flow cytometry brought up new questions about how to interpret live/dead staining results. intermediate states, normally difficult to detect with epifluorescence microscopy, are a common phenomenon when the assay is used in flow cytometry and still lack rationale. it is shown here that the application of propidium iodide in combinatio ... | 2007 | 17384309 |
| an anti-infective peptide that selectively modulates the innate immune response. | we show that an innate defense-regulator peptide (idr-1) was protective in mouse models of infection with important gram-positive and gram-negative pathogens, including methicillin-resistant staphylococcus aureus, vancomycin-resistant enterococcus and salmonella enterica serovar typhimurium. when given from 48 h before to 6 h after infection, the peptide was effective by both local and systemic administration. because protection by idr-1 was prevented by in vivo depletion of monocytes and macrop ... | 2007 | 17384586 |
| dot enzyme immunoassay (typhidot) in diagnosis of typhoid fever in children. | | 2007 | 17387102 |
| salmonella enteritidis in meat, poultry, and pasteurized egg products regulated by the u.s. food safety and inspection service, 1998 through 2003. | the u.s. food safety and inspection service (fsis) tests for salmonella in meat, poultry, and egg products through three regulatory testing programs: the pathogen reduction-hazard analysis and critical control point (pr-haccp) program, the ready-to-eat program for meat and poultry products, and the pasteurized egg products program. from 1998 through 2003, 293,938 samples collected for these testing programs were analyzed for the presence of salmonella enterica serotypes. of these samples, 12,699 ... | 2007 | 17388045 |
| eggshell penetration of various types of hens' eggs by salmonella enterica serovar enteritidis. | egg weight, shell thickness, number of pores, cuticle deposition, eggshell strength (dynamic stiffness and damping ratio), and the ability of salmonella enterica serovar enteritidis (se) to penetrate the eggshell were determined. penetration was assessed by filling the eggs with a selective medium that allowed viewing of salmonella growth on the inside of the shell and membrane complex. after inoculation of each shell with on average 2.71 log cfu, the eggs were stored for up to 14 days at 20 deg ... | 2007 | 17388050 |
| using aqueous chlorine dioxide to prevent contamination of tomatoes with salmonella enterica and erwinia carotovora during fruit washing. | chlorine dioxide (clo2) is an antimicrobial agent recognized for its disinfectant properties. in this study, the sanitizing effects of clo2 solutions against salmonella enterica and erwinia carotovora in water, on tomato surfaces, and between loads of tomatoes were evaluated. in water, clo2 at 5, 10, and 20 ppm caused a > or = 5-log reduction of s. enterica within 6, 4, and 2 s, respectively. higher lethality was observed with e. carotovora; a 5-log reduction was achieved after only 2 s with 10 ... | 2007 | 17388051 |
| salmonella pathogenicity island 4 encodes a giant non-fimbrial adhesin and the cognate type 1 secretion system. | pathogenicity islands play a major role in the pathogenesis of infections by salmonella enterica. the molecular function of salmonella pathogenicity island 4 (spi4) is largely unknown, but recent work indicated a role of spi4 for salmonella pathogenesis in certain animal models. we analysed the virulence functions of spi4 and observed that spi4 is contributing to intestinal inflammation in a mouse model. on a cellular level, spi4 mediates adhesion to epithelial cells. we demonstrate the function ... | 2007 | 17388786 |
| acquisition and diffusion of bla ctx-m-9 gene by r478-inchi2 derivative plasmids. | escherichia coli and salmonella enterica isolates carrying the bla(ctx-m-9) gene located on plasmids prevailed at the hospital de la santa creu i sant pau, barcelona, spain in the 1996-1999 period. the bla(ctx-m-9)-carrying plasmids showed a great variability in size, suggesting the mobilization of the gene among different plasmid scaffolds. the aim of the present work was to identify and better characterize the plasmids involved in the spread of the bla(ctx-m-9) gene. results showed that the ma ... | 2007 | 17391369 |
| comparison of the vidas system, fta filter-based pcr and culture on sm id for detecting salmonella in dermanyssus gallinae. | to compare different analytical methods for detecting salmonella in dermanyssus gallinae. | 2007 | 17397483 |
| growth rate toxicity phenotypes and homeostatic supercoil control differentiate escherichia coli from salmonella enterica serovar typhimurium. | escherichia coli and salmonella enterica serovar typhimurium share high degrees of dna and amino acid identity for 65% of the homologous genes shared by the two genomes. yet, there are different phenotypes for null mutants in several genes that contribute to dna condensation and nucleoid formation. the mutant r436-s form of the gyrb protein has a temperature-sensitive phenotype in salmonella, showing disruption of supercoiling near the terminus and replicon failure at 42 degrees c. but this muta ... | 2007 | 17400739 |
| yhdj, a nonessential ccrm-like dna methyltransferase of escherichia coli and salmonella enterica. | the caulobacter crescentus dna adenine methyltransferase ccrm and its homologs in the alpha-proteobacteria are essential for viability. ccrm is 34% identical to the yhdj gene products of escherichia coli and salmonella enterica. this study provides evidence that the e. coli yhdj gene encodes a dna adenine methyltransferase. in contrast to an earlier report, however, we show that yhdj is not an essential gene in either e. coli or s. enterica. | 2007 | 17400740 |
| microcin j25 has dual and independent mechanisms of action in escherichia coli: rna polymerase inhibition and increased superoxide production. | microcin j25 (mccj25) uptake by escherichia coli requires the outer membrane receptor fhua and the inner membrane proteins tonb, exbd, exbb, and sbma. mccj25 appears to have two intracellular targets: (i) rna polymerase (rnap), which has been described in e. coli and salmonella enterica serovars, and (ii) the respiratory chain, reported only in s. enterica serovars. in the current study, it is shown that the observed difference between the actions of microcin on the respiratory chain in e. coli ... | 2007 | 17400747 |
| unilateral orchitis and epididymitis caused by salmonella enterica subspecies diarizonae infection in a ram. | a case of unilateral suppurative epididymo-orchitis associated with salmonella enterica subsp. diarizonae serovar 61:k:1,5,(7) infection is described in a 2-year-old ram. gross lesions were characterized by severe enlargement of the scrotal contents, fibrous adhesions between testicular layers, coexistence of epididymal abscesses and foci of fibrinous exudate, and testicular atrophy. microscopically, testicular and epididymal microabscesses and diffuse inflammatory infiltrates with abundant macr ... | 2007 | 17402617 |
| systemic cd8 t-cell memory response to a salmonella pathogenicity island 2 effector is restricted to salmonella enterica encountered in the gastrointestinal mucosa. | to better understand the evolution of a systemic memory response to a mucosal pathogen, we monitored antigen-specific ot1 cd8 t-cell responses to a fusion of the ssph2 protein and the peptide siinfekl stably expressed from the chromosome of salmonella enterica and loaded into the class i pathway of antigen presentation of professional phagocytes through the salmonella pathogenicity island 2 type iii secretion system (ttss). this strategy has revealed that effector memory cd8 t cells with low lev ... | 2007 | 17403871 |
| application of pulsed-field gel electrophoresis to laboratory surveillance of small community outbreaks of salmonella enterica serovar typhimurium. | infectious diarrhea syndrome is an important cause of human morbidity around the world, and salmonella genus remains one of the most prevalent etiology. salmonella enterica serovar typhimurium outbreak-associated isolates received by the laboratory for enteric pathogens from n.i.r.d.m.i. "cantacuzino" for confirmation and typing were analyzed by genomic pulsed-field gel electrophoresis (pfge) and phage susceptibility testing to establish their relatedness. both typing methods proved to have simi ... | 2005 | 17405313 |
| evidence for glycosylation on a dna-binding protein of salmonella enterica. | all organisms living under aerobic atmosphere have powerful mechanisms that confer their macromolecules protection against oxygen reactive species. microorganisms have developed biomolecule-protecting systems in response to starvation and/or oxidative stress, such as dna biocrystallization with dps (dna-binding protein from starved cells). dps is a protein that is produced in large amounts when the bacterial cell faces harm, which results in dna protection. in this work, we evaluated the glycosy ... | 2007 | 17407574 |
| activity of synergistic combination amoxy-cassia against salmonella. | the object of this study was to formulate new, cost effective anti-microbial combination for multi drug resistant (mdr) salmonella enterica serover typhi (sest) based on the synergistic activity of amoxicillin with the aqueous fruit solution of cassia fistula (cff), a medicinal plant found in pakistan which when tested alone have weak antimicrobial activity against blood isolates of mdr sest. mic of mdr sest for amoxicillin and cff alone was 750 microg/ml and 3750 microg/ml. the mic of amoxicill ... | 2007 | 17416570 |
| structural properties of periplasmic sodci that correlate with virulence in salmonella enterica serovar typhimurium. | salmonella enterica strains survive and propagate in macrophages by both circumventing and resisting the antibacterial effectors normally delivered to the phagosome. an important aspect of salmonella resistance is the production of periplasmic superoxide dismutase to combat phagocytic superoxide. s. enterica serovar typhimurium strain 14028 produces two periplasmic superoxide dismutases: sodci and sodcii. both enzymes are produced during infection, but only sodci contributes to virulence in the ... | 2007 | 17416645 |
| the surface protease pgte of salmonella enterica affects complement activity by proteolytically cleaving c3b, c4b and c5. | complement activity in mammalian serum is fundamentally based on three homologous components c3b, c4b and c5. during systemic infection, the gastrointestinal pathogen salmonella enterica disseminates within host phagocytic cells but also extracellularly. consequently, systemic salmonella transiently confronts the complement system. we show here that the surface protease pgte of s. enterica proteolytically cleaves c3b, c4b and c5 and that the expression of pgte enhances bacterial resistance to hu ... | 2007 | 17418141 |
| serological and blood culture investigations of nepalese fever patients. | serological testing of paired (i.e. admission and convalescent) sera from 103 fever patients in kathmandu, nepal, was performed to estimate the prevalence rates of scrub typhus, murine typhus, leptospira and dengue virus antibodies and to determine their role in the cause of active infections. blood cultures from 15 patients grew salmonella enterica serovar typhi, 8 grew s. paratyphi a and 6 grew other bacteria. diagnostic antibody levels were detected against murine typhus (27/103; 26%), scrub ... | 2007 | 17433390 |
| in vivo priming heterophil innate immune functions and increasing resistance to salmonella enteritidis infection in neonatal chickens by immune stimulatory cpg oligodeoxynucleotides. | oligodeoxynucleotides (odn) containing cpg dinucleotides (cpg-odn) mimic bacterial dna and stimulate the innate immune system of vertebrates. here, we investigated the effects of intraperitoneal (ip) administered cpg-odn on the innate immune functions of chicken heterophils. our results demonstrated cpg-odn-dependent priming of chicken heterophil degranulation and oxidative burst. heterophils from chickens treated with cpg-odn exhibited significantly higher (p<0.05) degranulation activity compar ... | 2007 | 17434210 |
| aerobic and anaerobic growth modes and expression of type 1 fimbriae in salmonella. | the aim of this study was to clarify the growth rates of facultatively anaerobic salmonella enterica serovar enteritidis strain in aerobic and anaerobic conditions and the expression of type 1 fimbriae in relation to the growth phases. the cultivation was carried out in a portable microbe enrichment unit (pmeu) where in same conditions one can grow the cells in parallel by modifying, e.g. aerobiosis only. the results obtained show that although the anaerobic metabolism is generally believed to b ... | 2007 | 17434297 |
| protective immunity of biodegradable nanoparticle-based vaccine against an experimental challenge with salmonella enteritidis in mice. | salmonella spp. infections transmitted by contaminated poultry and eggs represent a major global health burden. salmonella enterica serovar. enteritidis is the leading cause of human salmonellosis worldwide. the cell surface antigens of salmonella enteritidis play an important role in the host-pathogen interactions and as such represent potential candidates for subunit-vaccine development. an immunogenic subcellular extract obtained from whole salmonella enteritidis cells (he) was encapsulated i ... | 2007 | 17434651 |
| plasmid-mediated quinolone resistance determinant qnrs1 found in salmonella enterica strains isolated in the uk. | to determine the prevalence of qnr genes in selected salmonella enterica and escherichia coli isolated in the uk. | 2007 | 17434878 |
| polyamine effects on antibiotic susceptibility in bacteria. | biogenic polyamines (e.g., spermidine and spermine) are a group of essential polycationic compounds found in all living cells. the effects of spermine and spermidine on antibiotic susceptibility were examined with gram-negative escherichia coli and salmonella enterica serovar typhimurium bacteria and clinical isolates of pseudomonas aeruginosa and with gram-positive staphylococcus aureus bacteria, including methicillin-resistant s. aureus (mrsa). exogenous spermine exerted a dose-dependent inhib ... | 2007 | 17438056 |
| weakening of salmonella with selected microbial metabolites of berry-derived phenolic compounds and organic acids. | gram-negative bacteria are important food spoilage and pathogenic bacteria. their unique outer membrane (om) provides them with a hydrophilic surface structure, which makes them inherently resistant to many antimicrobial agents, thus hindering their control. however, with permeabilizers, compounds that disintegrate and weaken the om, gram-negative cells can be sensitized to several external agents. although antimicrobial activity of plant-derived phenolic compounds has been widely reported, thei ... | 2007 | 17439151 |
| a hotel-based outbreak of salmonella enterica subsp. enterica serovar enteritidis (salmonella enteritidis) in the united kingdom, 2006. | an outbreak of food-borne salmonella enteritidis pt4 occurred in cumbria, in north-west england, in the summer of 2006. fifteen people, all with positive stool samples, met the case definition; three of these were admitted to hospital, including one patient who died. preliminary investigations suggested a link to a meal served at a local hotel. a case control study was implemented, together with microbiological and environmental investigations. fifteen microbiologically confirmed cases and 27 un ... | 2007 | 17439807 |
| treatment with anti-tnf alpha does not induce reactivation of latent salmonella enterica serovar typhimurium infection in c3h/hen mice. | therapy with tumour necrosis factor-alpha (tnfalpha)-blocking agents is successful in treating inflammatory disorders, but carries an increased risk of manifest and reactivating infection with intracellular bacteria. in a mouse model of latent salmonella typhimurium infection, neutralization of tnfalpha did not result in reactivation of infection, suggesting only a minor role for tnfalpha during latency of persistent salmonella infection. | 2007 | 17444950 |
| travel-acquired salmonellosis due to salmonella kentucky resistant to ciprofloxacin, ceftriaxone and co-trimoxazole and associated with treatment failure. | | 2007 | 17449886 |
| an oral salmonella vaccine promotes the down-regulation of cell surface toll-like receptor 4 (tlr4) and tlr2 expression in mice. | a single oral immunization with the lon-protease-deficient salmonella enterica serovar typhimurium (strain cs2022) induced protective immunity in mice against a subcutaneous challenge with virulent listeria monocytogenes as well as virulent salmonella serovar typhimurium. the populations of cell surface toll-like receptor 4 (tlr4) and tlr2 on peritoneal macrophages decreased at week 6 after immunization. this population decrease was not reversed after a challenge with either salmonella or lister ... | 2007 | 17451442 |
| type i interferon signaling is required for activation of the inflammasome during francisella infection. | francisella tularensis is a pathogenic bacterium whose virulence is linked to its ability to replicate within the host cell cytosol. entry into the macrophage cytosol activates a host-protective multimolecular complex called the inflammasome to release the proinflammatory cytokines interleukin (il)-1beta and -18 and trigger caspase-1-dependent cell death. in this study, we show that cytosolic f. tularensis subspecies novicida (f. novicida) induces a type i interferon (ifn) response that is essen ... | 2007 | 17452523 |
| [emergence of multidrug resistant salmonella strains in lome (togo)]. | this study had for aim to compare antibiotic resistance of 332 salmonella enterica strains identified in human samples in the course of infections, in lome. | 2007 | 17459634 |
| detection of pathogens in ovine and caprine abortion samples from sardinia, italy, by pcr. | during 2003-2005, 399 abortion samples (315 fetuses and 84 placentae) were collected from 107 ovine and caprine farms in northern sardinia. tissues from aborted fetuses and placentae were examined by pcr assay to detect dna from coxiella burnetii, chlamydophila abortus, salmonella enterica serovar abortusovis, toxoplasma gondii, and neospora caninum. the dna from at least 1 of these 5 infectious agents was amplified in 41% of ovine fetuses, while only 17% of the caprine fetuses yielded a positiv ... | 2007 | 17459840 |
| specific bifidobacterium strains isolated from elderly subjects inhibit growth of staphylococcus aureus. | cell-free, ph-controlled supernatants of thirty-eight bifidobacterium strains isolated from healthy elderly subjects were subjected to antimicrobial activity assay. bioluminescent indicator strains staphylococcus aureus rn4220, escherichia coli k-12, and salmonella enterica serovar typhimurium atcc 14028 were used as targets of antimicrobial activity. the effect of nutrient depletion on the inhibition was eliminated with spent-culture controls. three out of thirty-eight bifidobacterium strains w ... | 2007 | 17462772 |
| in vivo-selected mutations in methyl-directed mismatch repair suppress the virulence attenuation of salmonella dam mutant strains following intraperitoneal, but not oral, infection of naïve mice. | salmonella enterica serovar typhimurium that lacks the dna adenine methylase (dam) ectopically expresses multiple genes that are preferentially expressed during infection, is attenuated for virulence, and confers heightened immunity in vaccinated hosts. the safety of dam mutant salmonella vaccines was evaluated by screening within infected mice for isolates that have an increased capacity to cause disease relative to the attenuated parental strain. since dam mutant strains are sensitive to the d ... | 2007 | 17468250 |
| detection of escherichia coli o157, salmonella enterica serovar typhimurium, and staphylococcal enterotoxin b in a single sample using enzymatic bio-nanotransduction. | enzymatic bio-nanotransduction is a biological detection scheme based on the production of nucleic acid nano-signals (rna) in response to specific biological recognition events. in this study, we applied an enzymatic bio-nanotransduction system to the detection of important food-related pathogens and a toxin. escherichia coli o157:h7, salmonella enterica serovar typhimurium, and staphylococcal enterotoxin b (seb) were chosen because of the implications of these targets to food safety. primary an ... | 2007 | 17477251 |
| isolation of salmonella typhimurium from outbreak-associated cake mix. | during may and june of 2005, 26 persons in several states were infected by a single strain (isolates indistinguishable by pulsed-field gel electrophoresis) of salmonella enterica serotype typhimurium after eating cake batter ice cream. the cake mix used to prepare the cake batter in the ice cream was implicated by epidemiologic investigation as the source of salmonella contamination. initial tests did not detect salmonella in cake mix collected during the outbreak investigation. the objective of ... | 2007 | 17477273 |
| innate interferon response in macrophage and epithelial cells infected with wild-type compared to dna adenine methylase and flagellin mutant salmonella enterica serovar typhimurium. | salmonella enterica serovar typhimurium is highly virulent and mediates robust interferon (ifn)-stimulated gene (isg) induction, whereas bacterial mutants that lack the dna adenine methylase (dam) are attenuated, elicit a reduced isg activation profile, and establish immunity to murine typhoid fever. we show here that in contrast to observations in mice, infection of macrophage cell cultures with either wild-type (wt) or dam(-) mutant salmonella resulted in surprisingly similar kinetics and ampl ... | 2007 | 17477819 |
| evaluation of stocking density and subtherapeutic chlortetracycline on salmonella enterica subsp. enterica shedding in growing swine. | the objective of this research was to determine the effect of stocking density and inclusion of subtherapeutic chlortetracycline in the diet on salmonella fecal prevalence and antimicrobial resistance in growing swine. a 2 x 2 factorial design was employed on a privately owned commercial swine farm. four finisher rooms were included in the study. two of the rooms received 50 g/tonnes of chlortetracycline in the ration, two rooms received no antimicrobials in the feed. in each room, alternate pen ... | 2007 | 17482387 |
| a nosocomial, foodborne outbreak of salmonella enterica serovar enteritidis in a university hospital in greece: the importance of establishing haccp systems in hospital catering. | | 2007 | 17482719 |
| release of the lipopolysaccharide deacylase pagl from latency compensates for a lack of lipopolysaccharide aminoarabinose modification-dependent resistance to the antimicrobial peptide polymyxin b in salmonella enterica. | salmonella enterica modifies its lipopolysaccharide (lps), including the lipid a portion, to adapt to its environments. the lipid a 3-o-deacylase pagl exhibits latency; deacylation of lipid a is not usually observed in vivo despite the expression of pagl, which is under the control of a two-component regulatory system, phop-phoq. in contrast, pagl is released from latency in pmra and pmre mutants, both of which are deficient in aminoarabinose-modified lipid a, although the biological significanc ... | 2007 | 17483225 |
| delineation of the salmonella enterica serovar typhimurium hila regulon through genome-wide location and transcript analysis. | the salmonella enterica serovar typhimurium hila protein is the key regulator for the invasion of epithelial cells. by a combination of genome-wide location and transcript analysis, the hila-dependent regulon has been delineated. under invasion-inducing conditions, hila binds to most of the known target genes and a number of new target genes. the sopb, sope, and sopa genes, encoding effector proteins secreted by the type iii secretion system on salmonella pathogenicity island 1 (spi-1), were ide ... | 2007 | 17483226 |
| comparative evaluation of a bivalent killed salmonella vaccine to prevent egg contamination with salmonella enterica serovars enteritidis, typhimurium, and gallinarum biovar pullorum, using 4 different challenge models. | we evaluated a newly developed commercial bivalent killed salmonella vaccine oilvax set for its ability to decrease contamination with salmonella enterica serovars enteritidis and typhimurium in layer chickens. in either an oral or intravaginal challenge model, the fecal shedding was decreased in vaccinated hens, but egg contamination was not evaluated due to scarcity of contaminated eggs even in the unvaccinated control groups. in contrast, an intravenous and an intraperitoneal challenge result ... | 2007 | 17485152 |
| vapor-phase activities of cinnamon, thyme, and oregano essential oils and key constituents against foodborne microorganisms. | the aim of the study presented here was to gain knowledge about the vapor-phase antimicrobial activity of selected essential oils and their major putatively active constituents against a range of foodborne bacterial and fungal strains. in a first step, the vapor-phase antimicrobial activities of three commercially available essential oils (eos)-cinnamon (cinnamomum zeylanicum), thyme (thymus vulgaris), and oregano (origanum vulgare)-were evaluated against a wide range of microorganisms, includin ... | 2007 | 17488023 |
| effects of crp deletion in salmonella enterica serotype gallinarum. | salmonella enterica serotype gallinarum (s. gallinarum) remains an important pathogen of poultry, especially in developing countries. there is a need to develop effective and safe vaccines. in the current study, the effect of crp deletion was investigated with respect to virulence and biochemical properties and the possible use of a deletion mutant as vaccine candidate was preliminarily tested. | 2007 | 17488512 |
| influence of temperature fluctuations on escherichia coli o157:h7 and salmonella enterica serovar typhimurium in cow manure. | the effects of four average temperatures (7, 16, 23 and 33 degrees c) and daily oscillations with three amplitudes (0, +/-4, +/-7 degrees c) on the survival of the enteropathogens escherichia coli o157:h7 and salmonella serovar typhimurium were investigated in small microcosms. manure was inoculated with a green fluorescent protein transformed strain of either pathogen at 10(7) cells g(-1) dry weight. samples were collected immediately after inoculation, and 1 and 2 weeks after inoculation for e ... | 2007 | 17490417 |
| salmonella-induced sipb-independent cell death requires toll-like receptor-4 signalling via the adapter proteins tram and trif. | salmonella enterica serovar typhimurium (s. typhimurium) is an intracellular pathogen that causes macrophage cell death by at least two different mechanisms. rapid cell death is dependent on the salmonella pathogenicity island-1 protein sipb whereas delayed cell death is independent of sipb and occurs 18-24 hr post infection. lipopolysaccharide (lps) is essential for the delayed cell death. lps is the main structural component of the outer membrane of gram-negative bacteria and is recognized by ... | 2007 | 17490432 |
| genetic surveillance of endemic bovine salmonella infantis infection. | salmonella serovar infantis is endemic in finnish food-producing animals since the 1970s. the purpose of this study was to describe the molecular epidemiology of the infection in cattle during 1985-2005, to follow the persistence of the feed-related outbreak strain from 1995 in the cattle population, and to analyse the stability of xbai-banding patterns in individual herds during long-lasting infections. | 2007 | 17493281 |
| induction of specific immune responses by severe acute respiratory syndrome coronavirus spike dna vaccine with or without interleukin-2 immunization using different vaccination routes in mice. | dna vaccines induce humoral and cellular immune responses in animal models and humans. to analyze the immunogenicity of the severe acute respiratory syndrome (sars) coronavirus (cov), sars-cov, spike dna vaccine and the immunoregulatory activity of interleukin-2 (il-2), dna vaccine plasmids pcdna-s and pcdna-il-2 were constructed and inoculated into balb/c mice with or without pcdna-il-2 by using three different immunization routes (the intramuscular route, electroporation, or the oral route wit ... | 2007 | 17494640 |
| temperature-hypersensitive sites of the flagellar switch component flig in salmonella enterica serovar typhimurium. | three flagellar proteins, flig, flim, and flin (fligmn), are the components of the c ring of the flagellar motor. the genes encoding these proteins are multifunctional; they show three different phenotypes (fla(-), mot(-), and che(-)), depending on the sites and types of mutations. some of the mot(-) mutants previously characterized are found to be motile. reexamination of all mot(-) mutants in fligmn genes so far studied revealed that many of them are actually temperature sensitive (ts); that i ... | 2007 | 17496083 |
| a functional homing endonuclease in the bacillus anthracis nrde group i intron. | the essential bacillus anthracis nrde gene carries a self-splicing group i intron with a putative homing endonuclease belonging to the giy-yig family. here, we show that the nrde pre-mrna is spliced and that the homing endonuclease cleaves an intronless nrde gene 5 nucleotides (nt) upstream of the intron insertion site, producing 2-nt 3' extensions. we also show that the sequence required for efficient cleavage spans at least 4 bp upstream and 31 bp downstream of the cleaved coding strand. the p ... | 2007 | 17496101 |
| an efficient system for markerless gene replacement applicable in a wide variety of enterobacterial species. | we describe an improved allelic-exchange method for generating unmarked mutations and chromosomal dna alterations in enterobacterial species. initially developed for use in salmonella enterica, we have refined the method in terms of time, simplicity, and efficiency. we have extended its use into related bacterial species that are more recalcitrant to genetic manipulations, including enterohemorrhagic and enteropathogenic escherichia coli and vibrio parahaemolyticus. data from over 50 experiments ... | 2007 | 17496950 |
| a longitudinal study of environmental salmonella contamination in caged and free-range layer flocks. | the environmental contamination by salmonella was examined over a 12-month period in 74 commercial layer flocks from eight farms in the uk, which previously had been identified as being contaminated with salmonella. samples of faeces, dust, litter, egg belt spillage and wildlife vectors were taken, plus swabs of cages, feeders, drinkers, floors, egg belts and boots. some sampling was performed in each month of the year. numerous serovars were detected but salmonella enterica serotype enteritidis ... | 2007 | 17497330 |
| the salmonella pathogenicity island 1 and salmonella pathogenicity island 2 type iii secretion systems play a major role in pathogenesis of systemic disease and gastrointestinal tract colonization of salmonella enterica serovar typhimurium in the chicken. | salmonella enterica serovar typhimurium infection of chickens is a major public and animal health problem. in young chicks, s. typhimurium infection results in severe systemic infection; in older chicks, infection results in prolonged gastrointestinal tract colonization. here we determined the role of the salmonella pathogenicity island 1 (spi-1) and salmonella pathogenicity island 2 (spi-2) type iii secretion systems in systemic infection and gastrointestinal tract colonization of the chicken t ... | 2007 | 17497331 |
| membrane toxicity of antimicrobial compounds from essential oils. | natural antimicrobial compounds perform their action mainly against cell membranes. the aim of this work was to evaluate the interaction, meant as a mechanism of action, of essential oil antimicrobial compounds with the microbial cell envelope. the lipid profiles of escherichia coli o157:h7, staphylococcus aureus, salmonella enterica serovar typhimurium, pseudomonas fluorescens, and brochothrix thermosphacta cells treated with thymol, carvacrol, limonene, eugenol, and cinnamaldehyde have been an ... | 2007 | 17497876 |
| peptidyl boronates inhibit salmonella enterica serovar typhimurium lon protease by a competitive atp-dependent mechanism. | lon is a homo-oligomeric atp-dependent serine protease that functions in the degradation of damaged and certain regulatory proteins. this enzyme has emerged as a novel target in the development of antibiotics because of its importance in conferring bacterial virulence. in this study, we explored the mechanism by which the proteasome inhibitor mg262, a peptidyl boronate, inhibits the peptide hydrolysis activity of salmonella enterica serovar typhimurium lon. in addition, we synthesized a fluoresc ... | 2007 | 17497890 |
| biochemical and crystallographic analysis of substrate binding and conformational changes in acetyl-coa synthetase. | the adenylate-forming enzymes, including acyl-coa synthetases, the adenylation domains of non-ribosomal peptide synthetases (nrps), and firefly luciferase, perform two half-reactions in a ping-pong mechanism. we have proposed a domain alternation mechanism for these enzymes whereby, upon completion of the initial adenylation reaction, the c-terminal domain of these enzymes undergoes a 140 degrees rotation to perform the second thioester-forming half-reaction. structural and kinetic data of mutan ... | 2007 | 17497934 |
| the effects of the bt/tamus 2032 cationic peptides on innate immunity and susceptibility of young chickens to extraintestinal salmonella enterica serovar enteritidis infection. | the bt/tamus 2032 (bt) cationic peptides are a group of related cationic peptides produced by a gram-positive bacterium. cationic amphiphilic peptides have been found to stimulate or prime the innate immune responses in mammals. the innate immune system of poultry is functionally inefficient during the first week post-hatch enabling pathogens such as salmonella enterica serovar enteritidis (se) to invade and colonize the visceral organs of these immature birds. the objective of the present study ... | 2007 | 17499193 |
| global transcriptional response of porcine mesenteric lymph nodes to salmonella enterica serovar typhimurium. | to elucidate the host transcriptional response to salmonella enterica serovar typhimurium, affymetrix porcine genechip analysis of pig mesenteric lymph nodes was used to identify 848 genes showing differential expression across different times after inoculation or when compared to non-inoculated controls. annotation analyses showed that a high proportion of these differentially expressed (de) genes are involved in immune and inflammatory responses. t helper 1, innate/inflammatory, and antigen-pr ... | 2007 | 17499962 |
| a novel linear plasmid mediates flagellar variation in salmonella typhi. | unlike the majority of salmonella enterica serovars, salmonella typhi (s. typhi), the etiological agent of human typhoid, is monophasic. s. typhi normally harbours only the phase 1 flagellin gene (flic), which encodes the h:d antigen. however, some s. typhi strains found in indonesia express an additional flagellin antigen termed h:z66. molecular analysis of h:z66+ s. typhi revealed that the h:z66 flagellin structural gene (fljb(z66)) is encoded on a linear plasmid that we have named pbssb1. the ... | 2007 | 17500588 |