Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| mccj25 c-terminal is involved in rna-polymerase inhibition but not in respiration inhibition. | microcin j25 appears to have two intracellular targets: (1) rna polymerase, which was described in escherichia coli and salmonella enterica serovars, and (2) cell respiration in salmonella enterica serovars. c-terminal glycine amidation of the threaded segment localized in the mccj25 lariat ring region specifically blocked the rna-polymerase inhibition, but not the cell respiration inhibition and peptide uptake. these results suggest that different regions of the molecule are responsible for eac ... | 2005 | 15850794 |
| requirement of mgtc for brucella suis intramacrophage growth: a potential mechanism shared by salmonella enterica and mycobacterium tuberculosis for adaptation to a low-mg2+ environment. | a brucella suis mgtc mutant is defective for growth within macrophages and in low-mg(2+) medium. these phenotypes are strikingly similar to those observed with mgtc mutants from salmonella enterica and mycobacterium tuberculosis, two other pathogens that proliferate within phagosomes. mgtc appears as a remarkable virulence factor that would have been acquired by distantly related intracellular pathogens to contribute to the adaptation to a low-mg(2+) environment in the phagosome. | 2005 | 15845525 |
| infection of the reproductive tract and eggs with salmonella enterica serovar pullorum in the chicken is associated with suppression of cellular immunity at sexual maturity. | salmonella enterica serovar pullorum causes persistent infections in laying hens. splenic macrophages are the main site of persistence. at sexual maturity, numbers of bacteria increase and spread to the reproductive tract, which may result in vertical transmission to eggs or chicks. in this study we demonstrate that both male and female chickens may develop a carrier state following infection but that the increases in bacterial numbers and spread to the reproductive tract are phenomena restricte ... | 2005 | 15845505 |
| differential induction of the toll-like receptor 4-myd88-dependent and -independent signaling pathways by endotoxins. | the biological response to endotoxin mediated through the toll-like receptor 4 (tlr4)-md-2 receptor complex is directly related to lipid a structure or configuration. endotoxin structure may also influence activation of the myd88-dependent and -independent signaling pathways of tlr4. to address this possibility, human macrophage-like cell lines (thp-1, u937, and mm6) or murine macrophage raw 264.7 cells were stimulated with picomolar concentrations of highly purified endotoxins. harvested supern ... | 2005 | 15845500 |
| gamma irradiation or cd4+-t-cell depletion causes reactivation of latent salmonella enterica serovar typhimurium infection in c3h/hen mice. | upon infection with salmonella, a host develops an immune response to limit bacterial growth and kill and eliminate the pathogen. salmonella has evolved mechanisms to remain dormant within the body, only to reappear (reactivate) at a later time when the immune system is abated. we have developed an in vivo model for studying reactivation of salmonella enterica serovar typhimurium infection in mice. upon subcutaneous infection, c3h/hen (ity(r)) mice showed an increase in bacterial numbers in live ... | 2005 | 15845491 |
| characterization of salmonella-induced cell death in human macrophage-like thp-1 cells. | salmonella strains are facultative intracellular pathogens that produce marked cytopathology during infection of host cells. different forms of cytopathic effects have been associated with the virulence systems encoded by the two salmonella pathogenicity islands (spi-1 and spi-2) and the spv locus. we used salmonella enterica serovar dublin to investigate the induction of cytopathology during infection of the human macrophage-like cell line thp-1. analysis of host cells by flow cytometry using a ... | 2005 | 15845488 |
| emergence of salmonella epidemics: the problems related to salmonella enterica serotype enteritidis and multiple antibiotic resistance in other major serotypes. | two major changes in the epidemiology of salmonellosis occurred in the second half of the 20th century: the emergence of food-borne human infections caused by s. enteritidis and by multiple-antibiotic resistant strains of salmonella. this review updates information on the s. enteritidis pandemic and focuses on the emergence of salmonella, carrying the sgi1 antibiotic resistance gene cluster, resistant to extended-spectrum cephalosporins, or resistant to fluoroquinolones. the factors responsible ... | 2005 | 15845226 |
| eliminating the carriage of salmonella enterica serovar enteritidis in domestic fowls by feeding activated charcoal from bark containing wood vinegar liquid (nekka-rich). | the protective efficacy of activated charcoal containing wood vinegar liquid (nekka-rich) against intestinal infection with salmonella enterica serovar enteritidis was sought. in the present study, the adsorption effects of activated charcoal of nekka-rich on s. enteritidis and normal bacterial flora in the intestine, enterococcus faecium, were examined. s. enteritidis was effectively adsorbed by activated charcoal of nekka-rich. on the other hand, activated charcoal of nekka-rich showed lower b ... | 2005 | 15844805 |
| genetic and molecular analysis of gogb, a phage-encoded type iii-secreted substrate in salmonella enterica serovar typhimurium with autonomous expression from its associated phage. | salmonella enterica serovar typhimurium is lysogenized by several temperate bacteriophages that encode lysogenic conversion genes, which can act as virulence factors during infection and contribute to the genetic diversity and pathogenic potential of the lysogen. we have investigated the temperate bacteriophage called gifsy-1 in s.enterica serovar typhimurium and show here that the product of the gogb gene encoded within this phage shares similarity with proteins from other gram-negative pathoge ... | 2005 | 15843015 |
| macrophage cell death due to salmonella enterica serovar typhi and its acid stress protein has features of apoptosis. | salmonella spp. have been shown to cause apoptosis of various host cell types as a part of their infection process. however, the induction of apoptosis remains to be looked into under the different host environments including acidic stress experienced by the pathogen. in order to simulate the in vivo acidic conditions, we studied the potential of s. typhi and its protein expressed under in vitro acidic conditions to induce apoptosis in macrophages. murine macrophages were isolated and interacted ... | 2005 | 15840957 |
| a reduced level of charged trnaargmnm5ucu triggers the wild-type peptidyl-trna to frameshift. | frameshift mutations can be suppressed by a variety of differently acting external suppressors. the +1 frameshift mutation hisc3072, which has an extra g in a run of gs, is corrected by the external suppressor mutation suff44. we have shown that suff44 and five additional allelic suppressor mutations are located in the gene argu coding for the minor trnaargmnm5ucu and alter the secondary and/or tertiary structure of this trna. the c61u, g53a, and c32u mutations influence the stability, whereas t ... | 2005 | 15840821 |
| exopolysaccharide sugars contribute to biofilm formation by salmonella enterica serovar typhimurium on hep-2 cells and chicken intestinal epithelium. | recently, we demonstrated that salmonella enterica serovar typhimurium can form biofilm on hep-2 cells in a type 1 fimbria-dependent manner. previous work on salmonella exopolysaccharide (eps) in biofilm indicated that the eps composition can vary based upon the substratum on which the bacterial biofilm forms. we have investigated the role of genes important in the production of colanic acid and cellulose, common components of eps. a mutation in the colanic acid biosynthetic gene, wcam, was intr ... | 2005 | 15838049 |
| polyphosphate kinase protects salmonella enterica from weak organic acid stress. | mutants of salmonella enterica lacking polyphosphate kinase (ppk) grow poorly in the presence of the weak organic acids acetate, propionate, and benzoate. this sensitivity is corrected by methionine and seems to result from destabilization of meta (homoserine transsuccinylase), the first enzyme in methionine biosynthesis. the meta protein is known to be sensitive to thermal inactivation, and ppk mutants are more sensitive to heat-induced methionine auxotrophy. peroxide increases the sensitivity ... | 2005 | 15838036 |
| functional characterization of waal, a ligase associated with linking o-antigen polysaccharide to the core of pseudomonas aeruginosa lipopolysaccharide. | the o antigen of pseudomonas aeruginosa b-band lipopolysaccharide is synthesized by assembling o-antigen-repeat units at the cytoplasmic face of the inner membrane by nonprocessive glycosyltransferases, followed by polymerization on the periplasmic face. the completed chains are covalently attached to lipid a core by the o-antigen ligase, waal. in p. aeruginosa the process of ligating these o-antigen molecules to lipid a core is not clearly defined, and an o-antigen ligase has not been identifie ... | 2005 | 15838026 |
| precise excision and secondary transposition of tnphoa in non-motile mutants of a salmonella enterica serovar enteritidis clinical isolate. | mutagenesis with tnphoa has been widely used in many bacteria. here, we report the excision and secondary transposition of this transposon in three non-motile (flic, flif and motb) mutants of salmonella enterica serovar enteritidis (s. enteritidis). isolation of motile revertants showed that they were kanamycin resistant and conserved a copy of tnphoa in their genome in an insertion site different from the initial one. they also expressed an intact flagella. characterization of the motile revert ... | 2005 | 15837381 |
| a randomized comparison of oral chloramphenicol versus ofloxacin in the treatment of uncomplicated typhoid fever in laos. | we conducted a randomized open trial of oral chloramphenicol (50mg/kg/day in four divided doses for 14 days) versus ofloxacin (15 mg/kg/day in two divided doses for 3 days) in 50 adults with culture-confirmed uncomplicated typhoid fever in vientiane, laos. patients had been ill for a median (range) of 8 (2-30) days. all salmonella enterica serotype typhi isolates were nalidixic acid-sensitive, four (8%) were chloramphenicol-resistant and three (6%) were multidrug-resistant. median (range) fever ... | 2005 | 15837357 |
| effectiveness of trisodium phosphate treatment against pathogenic and spoilage bacteria on poultry during refrigerated storage. | to determine the efficacy of trisodium phosphate (tsp) against pathogenic and spoilage bacteria on poultry and to assess the influence of the bacterial combination of inoculum on tsp effect, chicken legs were coinoculated with similar concentrations of a pathogenic (salmonella enterica ser. enteritidis or listeria monocytogenes) and a spoilage (pseudomonas fluorescens or brochothrix thermosphacta) bacteria. samples were dipped in tsp (12%, 15 min) or were not treated (control). microbiological a ... | 2005 | 15830686 |
| destruction of salmonella senftenberg on the shells of intact eggs by thermoultrasonication. | the combined effect of ultrasonic waves and heat treatment applied simultaneously was evaluated on the survival of strains of salmonella senftenberg on shells of intact eggs. this combined process has a higher killing effect than heat treatment alone. the decimal reduction times (d-values) were decreased by 65.2 to 11.1% in the temperature range studied (57.8 to 67 degrees c). in contrast to the effect on salmonella enterica serovar enteritidis in a previous study, thermoultrasonication had no i ... | 2005 | 15830681 |
| growth of salmonella enterica serovar enteritidis in albumen and yolk contents of eggs inoculated with this organism onto the vitelline membrane. | by using an in vitro model simulating the potential opportunities for salmonella enterica serovar enteritidis (se) to proliferate within eggs contaminated with this organism following oviposition, we investigated growth of se in eggs. seventy to 140 cfu of one of three se strains originating either from egg contents, chicken meat, or a human infection were experimentally inoculated onto the vitelline membrane of eggs collected from specific-pathogen-free flocks of chickens and incubated at 25 de ... | 2005 | 15830661 |
| inactivation of salmonella enterica serovar enteritidis on shell eggs by ozone and uv radiation. | the presence of salmonella enterica serovar enteritidis in shell eggs has serious public health implications. several treatments have been developed to control salmonella on eggs with mixed results. currently, there is a need for time-saving, economical, and effective egg sanitization treatments. in this study, shell eggs externally contaminated with salmonella (8.0 x 10(5) to 4.0 x 10(6) cfu/g of eggshell) were treated with gaseous ozone (o3) at 0 to 15 lb/in2 gauge for 0 to 20 min. in other ex ... | 2005 | 15830660 |
| thermal resistance of salmonella enterica serotypes, listeria monocytogenes, and staphylococcus aureus in high solids liquid egg mixes. | decimal reduction times (d-values) were determined for salmonella enterica serotypes, listeria monocytogenes, and staphylococcus aureus in two high solids egg mixes designated a and b (water activity [a(w)] = 0.76 and 0.82; solids = 53.12 and 52.63%; ph = 5.09 and 5.29; viscosity = 183 and 119 centipoise/s, respectively) using a low-volume (0.06 ml) sealed glass capillary tube procedure. for salmonella, d-values ranged from 0.035 (70 degrees c) to 0.193 min (64 degrees c) in product a and from 0 ... | 2005 | 15830659 |
| web-based investigation of multistate salmonellosis outbreak. | we investigated a large outbreak of salmonella enterica serotype javiana among attendees of the 2002 u.s. transplant games, including 1,500 organ transplant recipients. web-based survey methods identified pre-diced tomatoes as the source of this outbreak, which highlights the utility of such investigative tools to cope with the changing epidemiology of foodborne diseases. | 2005 | 15829202 |
| purification and characterization of deacylated and/or palmitoylated lipid a species unique to salmonella enterica serovar typhimurium. | the salmonella enterica serovar typhimurium virulence gene products phop/phoq sense host microenvironments to regulate the expression of a lipid a 3-o-deacylase, pagl, and a lipid a palmitoyltransferase, pagp. therefore, deacylation and/or palmitoylation of lipid a could occur in salmonellae adapted to host environments. the phop/phoq-regulated modification of lipid a alters host recognition and signaling, and may play an important role in host defense against salmonellae infection. here we repo ... | 2005 | 15826380 |
| multidrug-resistant shigella sonnei and salmonella enterica serotype typhimurium isolates producing ctx-m beta-lactamases as causes of community-acquired infection in france. | 2005 | 15825010 | |
| invasive infection with multidrug-resistant salmonella enterica serotype typhimurium definitive type 104 among hiv-infected adults. | multidrug-resistant salmonella enterica serotype typhimurium definitive type 104 (mrdt104), with resistance to at least ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (r-type acssut), was first detected in the united states in 1985, and the prevalence increased to account for nearly 7% of salmonella infections in 1998. | 2005 | 15824994 |
| differential contribution of sodc1 and sodc2 to intracellular survival and pathogenicity of salmonella enterica serovar choleraesuis. | several of the most virulent salmonella enterica strains possess two genes encoding periplasmic cu,zn superoxide dismutase, sodc1 and sodc2, located on a lambdoid prophage and on the chromosome, respectively. these genes contribute to salmonella virulence by protecting bacteria from superoxide generated by the host's phagocytes. to investigate the respective contributions of sodc1 and sodc2 to the virulence of a clinical isolate of salmonella enterica serovar choleraesuis (s. choleraesuis), we h ... | 2005 | 15823516 |
| factors associated with variation in bulk-tank-milk salmonella dublin elisa odc% in dairy herds. | our objective was to determine factors that contribute to variation in bulk-tank-milk salmonella dublin enzyme-linked immunosorbent assays (elisa) corrected optic-density measurements (odc%) in dairy herds. we constructed hierarchical mixed models with repeated bulk-tank-milk elisa odc% in 31 danish dairy herds. four models included different combinations of explanatory factors, and we compared how well these models described the variation in the data. herd was included as a random effect nested ... | 2005 | 15820114 |
| alternative sigma factor interactions in salmonella: sigma and sigma promote antioxidant defences by enhancing sigma levels. | hierarchical interactions between alternative sigma factors control sequential gene expression in gram-positive bacteria, whereas alternative sigma factors in gram-negative bacteria are generally regarded to direct expression of discrete gene subsets. in salmonella enterica serovar typhimurium (s. typhimurium), sigma(e) responds to extracytoplasmic stress, whereas sigma(h) responds to heat shock and sigma(s) is induced during nutrient limitation. deficiency of sigma(e), sigma(h) or sigma(s) incr ... | 2005 | 15819634 |
| the alternative sigma factor sigma is required for resistance of salmonella enterica serovar typhimurium to anti-microbial peptides. | the enteric pathogen salmonella enterica serovar typhimurium (s. typhimurium) encounters a variety of anti-microbial peptides during the course of infection. we report here that the extracytoplasmic sigma factor sigma(e) (rpoe) is required for salmonella resistance to killing by the bactericidal/permeability-increasing protein (bpi)-derived peptide p2 and the murine alpha-defensin cryptdin-4 (crp4). moreover, sigma(e)-deficient s. typhimurium is attenuated for virulence after oral infection of i ... | 2005 | 15819632 |
| characterization of the rdar morphotype, a multicellular behaviour in enterobacteriaceae. | the rdar morphotype, a multicellular behaviour of salmonella enterica and escherichia coli is characterized by the expression of the adhesive extracellular matrix components cellulose and curli fimbriae. the response regulator csgd, which transcriptionally activates the biosynthesis of the exopolysaccharide cellulose and curli, also transforms cell physiology to the multicellular state. however, the only role of csgd in cellulose biosynthesis is the activation of adra, a ggdef domain protein tha ... | 2005 | 15818467 |
| biochemical evidence that the pdus gene encodes a bifunctional cobalamin reductase. | salmonella enterica degrades 1,2-propanediol (1,2-pd) by a pathway that requires coenzyme b(12) (adenosylcobalamin; adocbl). the genes specifically involved in 1,2-pd utilization (pdu) are found in a large contiguous cluster, the pdu locus. earlier studies have indicated that this locus includes genes for the conversion of vitamin b(12) (cyanocobalamin; cncbl) to adocbl and that the pduo gene encodes an atp : cob(i)alamin adenosyltransferase which catalyses the terminal step of this process. her ... | 2005 | 15817784 |
| prpz, a salmonella enterica serovar typhi serine/threonine protein phosphatase 2c with dual substrate specificity. | genes encoding eukaryotic-type protein kinases and phosphatases are present in many bacterial genomes. an orf encoding a polypeptide with homology to protein phosphatases 2c (pp2cs) was identified in the genomes of salmonella enterica serovar typhi strains ct18 and ty2. this protein, termed prpz, is the first pp2c to be identified in enterobacteria. analysis of the amino acid sequence revealed two distinct domains: the n-terminal segment containing motifs of the catalytic domain of pp2cs and the ... | 2005 | 15817783 |
| bacterial flagellar diversity in the post-genomic era. | flagellar biosynthesis has been studied most thoroughly in laboratory strains of escherichia coli and salmonella enterica. however, genome sequencing has uncovered flagellar loci in distantly related bacteria. we have used homology searches to determine how far the e. coli/s. enterica paradigm can be generalised to other flagellar systems. numerous previously unrecognized homologues of flagellar components were discovered, including novel flgm, flgn, flik and flio homologues. homology was found ... | 2005 | 15817382 |
| an outbreak of multidrug-resistant salmonella enterica serotype newport infections linked to the consumption of imported horse meat in france. | in 2003, 14 cases of multidrug-resistant salmonella newport infections were reported. this is the first documented foodborne outbreak of multidrug-resistant s. newport in france. the blacmy gene was present in all isolates. all cases reported having eaten horse meat from a common wholesaler. the country of origin of the imported meat could not be identified. | 2005 | 15816165 |
| discrimination within phenotypically closely related definitive types of salmonella enterica serovar typhimurium by the multiple amplification of phage locus typing technique. | multilocus sequence typing (mlst) is a relatively new high-resolution typing system employed for epidemiological studies of bacteria, including salmonella. discrimination based on mlst of housekeeping genes may be problematical, due to the high identity of gene sequences of closely related salmonella species. the presence of genomic sequences derived from stable temperate phages in salmonella offers an alternative for mlst of salmonella. we have used mlst of prophage loci in salmonella enterica ... | 2005 | 15814973 |
| tolc but not acrb is essential for multidrug-resistant salmonella enterica serotype typhimurium colonization of chicks. | to study the role of the multidrug efflux system acrab-tolc in resistance of multidrug-resistant salmonella enterica serotype typhimurium (s. typhimurium) phage type dt104 and dt204 strains to detergents and bile salts. to evaluate the importance of the inner membrane transporter acrb and the outer membrane component tolc of this efflux system in the colonization of two multidrug-resistant s. typhimurium dt104 and one dt204 strain in chicks. | 2005 | 15814604 |
| co-regulation of salmonella enterica genes required for virulence and resistance to antimicrobial peptides by slya and phop/phoq. | analysis of the transcriptome of slya mutant salmonella enterica serovar typhimurium revealed that many slya-dependent genes, including pagc, pagd, ugtl, mig-14, virk, phon, pgte, pipb2, sopd2, pagj and pagk, are also controlled by the phop/phoq regulatory system. many slya- and phop/phoq-co-regulated genes have functions associated with the bacterial envelope, and some have been directly implicated in virulence and resistance to antimicrobial peptides. purified his-tagged slya binds to the pagc ... | 2005 | 15813739 |
| biotinylation facilitates the uptake of large peptides by escherichia coli and other gram-negative bacteria. | gram-negative bacteria such as escherichia coli can normally only take up small peptides less than 650 da, or five to six amino acids, in size. we have found that biotinylated peptides up to 31 amino acids in length can be taken up by e. coli and that uptake is dependent on the biotin transporter. uptake could be competitively inhibited by free biotin or avidin and blocked by the protonophore carbonyl m-chlorophenylhydrazone and was abolished in e. coli mutants that lacked the biotin transporter ... | 2005 | 15812011 |
| catabolite repression of the propionate catabolic genes in escherichia coli and salmonella enterica: evidence for involvement of the cyclic amp receptor protein. | previous studies with salmonella enterica serovar typhimurium lt2 demonstrated that transcriptional activation of the prpbcde operon requires the function of transcription factor prpr, sigma-54, and ihf. in this study, we found that transcription from the prpbcde and prpr promoters was down-regulated by the addition of glucose or glycerol, indicating that these genes may be regulated by the cyclic amp (camp)-camp receptor protein (crp) complex. targeted mutagenesis of a putative crp-binding site ... | 2005 | 15805526 |
| regulation of nad synthesis by the trifunctional nadr protein of salmonella enterica. | the three activities of nadr were demonstrated in purified protein and assigned to separate domains by missense mutations. the n-terminal domain represses transcription of genes for nad synthesis and salvage. the c-terminal domain has nicotinamide ribose kinase (nmr-k; ec 2.7.1.22) activity, which is essential for assimilation of nmr, converting it internally to nicotinamide mononucleotide (nmn). the central domain has a weak adenylyltransferase (nmn-at; ec 2.7.7.1) activity that converts nmn di ... | 2005 | 15805524 |
| diversity of genome structure in salmonella enterica serovar typhi populations. | the genomes of most strains of salmonella and escherichia coli are highly conserved. in contrast, all 136 wild-type strains of salmonella enterica serovar typhi analyzed by partial digestion with i-ceui (an endonuclease which cuts within the rrn operons) and pulsed-field gel electrophoresis and by pcr have rearrangements due to homologous recombination between the rrn operons leading to inversions and translocations. recombination between rrn operons in culture is known to be equally frequent in ... | 2005 | 15805510 |
| slya regulates the collagenase-mediated cytopathic phenotype in multiresistant salmonella. | salmonella enterica serotype typhimurium phagetype dt104 (dt104) is a foodborne pathogen with a multiresistant phenotype conferred by a genomic-based integron structure designated as sgi1. recently, a novel cytopathic phenotype was ascribed to several isolates of dt104 recovered from veal calves. this phenotype is dependent upon clg, a gene encoding a collagenase in salmonella. using a novel transposon system and an rt-pcr assay for detection of clg expression, we identified slya as a regulator ... | 2005 | 15797813 |
| dna methylation modulates salmonella enterica serovar typhimurium virulence in caenorhabditis elegans. | salmonella enterica serovar typhimurium was previously shown to be virulent in caenorhabditis elegans. here we demonstrate that dna adenine methyltransferase (dam) modulates salmonella virulence in the nematode, as it does in mice. after 5 days of continual exposure to bacteria, twice as many worms died when exposed to the wild-type than the dam-mutant strain of salmonella. similar trends in virulence were observed when worms were exposed to salmonella strains for 5 h and transferred to the avir ... | 2005 | 15796979 |
| dietary fructooligosaccharides increase intestinal permeability in rats. | we showed previously that fructooligosaccharides (fos) decrease the resistance to salmonella infection in rats. however, the mechanism responsible for this effect is unclear. therefore, we examined whether dietary fos affects intestinal permeability before and after infection with salmonella enterica serovar enteritidis. male wistar rats were fed restricted quantities of a purified diet that mimicked the composition of a western human diet. the diet was supplemented with 60 g/kg cellulose (contr ... | 2005 | 15795444 |
| comparison of fecal culture and danish mix-elisa for determination of salmonella enterica subsp. enterica prevalence in growing swine. | in the usa, control of food-borne salmonellosis associated with meat consumption has been predominantly focused at slaughter and processing. it is expected that standards at slaughter and processing will become more stringent, creating pressure to reduce prevalence of salmonella-positive food animals through on-farm interventions. the aim of this study was to compare traditional fecal culture and the danish mix-elisa (dme) for determination of salmonella prevalence pre-harvest in swine. in trial ... | 2005 | 15795083 |
| an attenuated salmonella enteritidis strain derivative of the main genotype circulating in uruguay is an effective vaccine for chickens. | we have recently reported that salmonella enterica serovar enteritidis (s. enteritidis) strains circulating in uruguay, are unevenly distributed among different genetic subtypes, with a predominant genotype that is a common contaminant of poultry-derived food and that accounts for the vast majority of human cases of food-borne disease. herein, we describe the construction of a genetically-defined aroc derivative (lvr02) of a local strain of s. enteritidis belonging to the major genetic type. we ... | 2005 | 15795080 |
| [outbreak of salmonella enteriditis food poisoning at a dining hall facility]. | an outbreak of salmonella enteriditis food poisoning having occurred at two banquet halls, affecting eight groups of guests, is described. this research was aimed at determining the food by means of which this illness was transmitted. | 2005 | 15794585 |
| rollback of salmonella enterica serotype typhi resistance to chloramphenicol and other antimicrobials in kolkata, india. | 2005 | 15793167 | |
| bactericidal and antiendotoxic properties of short cationic peptides derived from a snake venom lys49 phospholipase a2. | the activities of short synthetic, nonhemolytic peptides derived from the c-terminal region of myotoxin ii, a catalytically inactive phospholipase a2 homologue present in the venom of the snake bothrops asper, have been shown to reproduce the bactericidal activity of the parent protein. they combine cationic and hydrophobic-aromatic amino acids, thus functionally resembling the antimicrobial peptides of innate defenses. this study evaluated the antimicrobial and antiendotoxic properties of a 13- ... | 2005 | 15793109 |
| bla(ctx-m) genes in clinical salmonella isolates recovered from humans in england and wales from 1992 to 2003. | cefotaximases (ctx-m) are a rapidly growing class a beta-lactamase family that has been found among a wide range of clinical bacteria. one hundred and six isolates were selected from 278,308 salmonella isolates based on resistance to ampicillin and cephalosporins and subjected to further characterization. fourteen isolates were bla(ctx-m) pcr positive, and cefotaxime mics for these isolates were > or = 16 mg/liter. furthermore, sequence analysis revealed the presence of type ctx-m9, -15, or -17 ... | 2005 | 15793104 |
| role of salmonella surface components in immunomodulation of inflammatory mediators. | salmonella enterica serovar typhimurium and its surface components were assessed for their inflammatory potential by footpad oedema test using plethysmometer. inflammation was found to be the highest when outer membrane proteins (omps) were used as inflammagen followed by lipid associated protein-lipopolysaccharide complex (lap-lps) and lipopolysaccharides (lps). inflammation produced by omps was found to be comparable to that by carrageenan (a known positive inflammagen). however, injection of ... | 2005 | 15792366 |
| the role of host cell death in salmonella infections. | salmonella enterica is an important enteric pathogen of humans and a variety of domestic and wild animals. infection is initiated in the intestinal tract, and severe disease produces widespread destruction of the intestinal mucosa. salmonella strains can also disseminate from the intestine and produce serious, sometimes fatal infections with considerable cytopathology in a number of systemic organs. a combination of bacterial genetic and cell biology studies have shown that salmonella uses speci ... | 2005 | 15791954 |
| hierarchical gene regulators adapt salmonella enterica to its host milieus. | the facultative intracellular pathogen salmonella enterica serovar typhimurium possesses an elaborate set of virulence genes that enables the bacterium successfully to move between and adapt to the environment, different host organisms and various micro-niches within a given host. expression of virulence attributes is by no means constitutive. rather, the regulation of virulence determinants is highly coordinated and integrated into normal bacterial physiological responses. by integrating discri ... | 2005 | 15790293 |
| molecular epidemiology of salmonella enterica serovar enteritidis strains by pulsed-field gel electrophoresis isolated in the slovak republic. | a total 44 isolates of s. enterica serovar enteritidis (s. enteritidis) belonged to three different phage types (pts) 9a, 13a, 25 were analyzed by the technique of pulsed-field gel electrophoresis (pfge). thirty and three strains were from two outbreaks (central and southern regions of the slovak republic pts 13a, 25) and 11 isolates were sporadic isolates (pt9a). these isolates showed two different patterns in pfge with xbai digestion. strains of pt13a generated pfp a and isolates of pt25 showe ... | 2004 | 15790080 |
| multiple antimicrobial resistant salmonella enterica serovar paratyphi b variant java in cattle: a case report. | an epidemiological investigation of a calf rearing premises and a closely associated dairy herd was carried out after the isolation of salmonella enterica serovar paratyphi b variant java phage type 3b variant 2 from clinically diseased calves on the premises. the isolate was resistant to ampicillin, chloramphenicol, streptomycin, sulphonamides, tetracyclines, trimethoprim and cefoperazone. the organism was widespread on the calf unit and was also recovered from the dairy premises, mainly from g ... | 2005 | 15789647 |
| identification and functional characterization of chicken toll-like receptor 5 reveals a fundamental role in the biology of infection with salmonella enterica serovar typhimurium. | toll-like receptors (tlrs) are a major component of the pattern recognition receptor repertoire that detect invading microorganisms and direct the vertebrate immune system to eliminate infection. in chickens, the differential biology of salmonella serovars (systemic versus gut-restricted localization) correlates with the presence or absence of flagella, a known tlr5 agonist. chicken tlr5 (chtlr5) exhibits conserved sequence and structural similarity with mammalian tlr5 and is expressed in tissue ... | 2005 | 15784580 |
| mouse paneth cell secretory responses to cell surface glycolipids of virulent and attenuated pathogenic bacteria. | mouse paneth cells respond to bacteria and bacterial cell surface antigens by discharging secretory granules into the lumen of small intestinal crypts (t. ayabe et al., nat. immunol. 1:113-118, 2000). to investigate mechanisms regulating these responses, purified surface glycolipid molecules with known acyl chain modifications and attenuated properties were tested for the ability to stimulate paneth cell secretion. the antigens included lipopolysaccharide (lps) from wild-type and msbb-null esche ... | 2005 | 15784576 |
| antibiotic-free plasmid stabilization by operator-repressor titration for vaccine delivery by using live salmonella enterica serovar typhimurium. | live, attenuated bacteria are effective vectors for heterologous antigen delivery. however, loss of heterologous gene-bearing plasmids is problematic, and antibiotics and their resistance genes are not desirable for in vivo dna vaccine delivery due to biosafety and regulatory concerns. to solve this problem, we engineered the first vaccine delivery strain that has no requirement for antibiotics or other selectable marker genes to maintain the recombinant plasmid. this model strain of salmonella ... | 2005 | 15784541 |
| cloning and sequencing of a genomic island found in the brazilian purpuric fever clone of haemophilus influenzae biogroup aegyptius. | a genomic island was identified in the haemophilus influenzae biogroup aegyptius brazilian purpuric fever (bpf) strain f3031. this island, which was also found in other bpf isolates, could not be detected in non-bpf biogroup aegyptius strains or in nontypeable or typeable h. influenzae strains, with the exception of a region present in the type b eagan strain. this 34,378-bp island is inserted, in reference to h. influenzae rd kw20, within a choline transport gene and contains a mosaic structure ... | 2005 | 15784532 |
| salmonella enterica serovar typhi with decreased susceptibility to ciprofloxacin--an emerging problem in bangladesh. | 2005 | 15784317 | |
| purification and characterization of rihc, a xanthosine-inosine-uridine-adenosine-preferring hydrolase from salmonella enterica serovar typhimurium. | salmonella enterica serovar typhimurium normally salvage nucleobases and nucleosides by the action of nucleoside phosphorylases and phosphoribosyltransferases. in contrast to escherichia coli, which catabolizes xanthosine by xanthosine phosphorylase (xapa), salmonella cannot grow on xanthosine as the sole carbon and energy source. by functional complementation, we have isolated a nucleoside hydrolase (rihc) that can complement a xapa deletion in e. coli and we have overexpressed, purified and ch ... | 2005 | 15784179 |
| protective efficacy of maternal antibodies induced by salmonella toxoid (vaccine). | an attempt was made to evaluate the protective efficacy of maternal antibodies in chicks against salmonellosis. layer chicks ageing 21 days were individually vaccinated with 100 microg of salmonella enterica subspecies enterica serovar weltevreden (bm 1643) toxoid adjuvanted with vitamin e subcutaneously. after 90 days of the primary vaccination the birds were given booster dose of the vaccine. the saline extract of the yolk of eggs laid by the vaccinated birds yielded agglutination and elisa ti ... | 2005 | 15782817 |
| the genome sequence of salmonella enterica serovar choleraesuis, a highly invasive and resistant zoonotic pathogen. | salmonella enterica serovar choleraesuis (s. choleraesuis), a highly invasive serovar among non-typhoidal salmonella, usually causes sepsis or extra-intestinal focal infections in humans. s. choleraesuis infections have now become particularly difficult to treat because of the emergence of resistance to multiple antimicrobial agents. the 4.7 mb genome sequence of a multidrug-resistant s. choleraesuis strain sc-b67 was determined. genome wide comparison of three sequenced salmonella genomes revea ... | 2005 | 15781495 |
| evaluation of an intracellular-activated promoter for the generation of live salmonella recombinant vaccines. | salmonella enterica serovar typhimurium is a versatile host organism for the generation of recombinant live vaccines for mucosal immunization. we investigated the performance of an intracellular-activated promoter for expression of heterologous antigens by salmonella carrier strains. we observed that intracellular expressed antigens were more efficient in elicitation of humoral and cellular immune responses than constitutively expressed antigens. furthermore, the intracellular-activated promoter ... | 2005 | 15780440 |
| analysis of the hypervariable region of the salmonella enterica genome associated with trna(leux). | the divergence of salmonella enterica and escherichia coli is estimated to have occurred approximately 140 million years ago. despite this evolutionary distance, the genomes of these two species still share extensive synteny and homology. however, there are significant differences between the two species in terms of genes putatively acquired via various horizontal transfer events. here we report on the composition and distribution across the salmonella genus of a chromosomal region designated sp ... | 2005 | 15774890 |
| inhibition of salmonella enterica serovar typhimurium lipopolysaccharide deacylation by aminoarabinose membrane modification. | salmonella enterica serovar typhimurium remodels the lipid a component of lipopolysaccharide, a major component of the outer membrane, to survive within animals. the activation of the sensor kinase phoq in host environments increases the synthesis of enzymes that deacylate, palmitoylate, hydroxylate, and attach aminoarabinose to lipid a, also known as endotoxin. these modifications promote bacterial resistance to antimicrobial peptides and reduce the host recognition of lipid a by toll-like rece ... | 2005 | 15774888 |
| monitoring age-related susceptibility of young mice to oral salmonella enterica serovar typhimurium infection using an in vivo murine model. | neonates and young children are acutely susceptible to infections by gastrointestinal bacterial pathogens, such as salmonella enterica serovar typhimurium (s. typhimurium). to reveal age-related differences in susceptibility to this pathogen, we used in vivo bioluminescence imaging (bli) to monitor the progression of infection in neonatal (1-wk-old), suckling (2-wk-old), juvenile (4-wk-old), and adult (6-wk-old) balb/c mice. mice were orally infected with various doses of a bioluminescent-labele ... | 2005 | 15774831 |
| [infective etiology of diarrhea in adults with hiv infection in dakar: a case-control study on 594 patients]. | a survey was conducted in dakar, senegal from may 1997 to may 1999, to identify major types and prevalences of bacteria, parasites, fungi and rotaviruses associated with diarrhea in relation to human immunodeficiency virus serostatus with the aim to provide guidance to physicians for case management. etiologic agents were identified in a case-control study: cases were hiv-infected patients with diarrhea (hiv+ d+) and hiv seronegative patients with diarrhea (hiv- d+); controls were hiv-infected p ... | 2001 | 15773157 |
| antimicrobial resistance patterns and serotype distribution among salmonella enterica strains in turkey, 2000-2002. | since turkey currently lacks a national reference center for salmonella infections, the present study was conducted to document the distribution of serotypes and antimicrobial resistance patterns among salmonella enterica isolates recovered from clinical samples in ten turkish provinces over a 2-year period. among the 620 salmonella enterica isolates recovered between 1 july 2000 and 30 june 2002, strains belonging to the serotypes enteritidis (47.7%), typhimurium (34.7%), paratyphi b (6.0%), ty ... | 2005 | 15772822 |
| combination of immunomagnetic separation with real-time pcr for rapid detection of salmonella in milk, ground beef, and alfalfa sprouts. | a rapid, specific, and sensitive method for detecting salmonella spp. in pasteurized milk, ground beef, and alfalfa sprouts was developed. the method combined immunomagnetic separation with a real-time pcr assay based on the double-stranded dna binding dye sybr green i. the primers used produced a product with a melting temperature of 87+/-0.5 degrees c during the pcr assay by amplifying a 284-bp sequence from the invasive gene (inva) of salmonella. the method was successful in detecting 20 salm ... | 2005 | 15771182 |
| interaction of salmonella enterica subspecies enterica serovar typhimurium and mung bean (phaseolus aureus) plants. | the effect of salmonella enterica subspecies enterica serovar typhimurium, a zoonotic serovar, on mung bean (phaseolus aureus) cultivar pant mung-3 plants was studied. inoculation of mung bean seeds with salmonella typhimurium (7.2 x 10(5) cfu/ml) reduced sprouting rate (p < 0.07). this effect was more pronounced at higher levels of contamination. in the soil inoculated with salmonella typhimurium (7.2 x 10(6) cfu/g), germination was retarded and the number of defective sprouts was also signific ... | 2005 | 15771169 |
| rapid phenotypic characterization of salmonella enterica strains by pyrolysis metastable atom bombardment mass spectrometry with multivariate statistical and artificial neural network pattern recognition. | pyrolysis mass spectrometry was investigated for rapid characterization of bacteria. spectra of salmonella were compared to their serovars, pulsed-field gel electrophoresis (pfge) patterns, antibiotic resistance profiles, and mic values. pyrolysis mass spectra generated via metastable atom bombardment were analyzed by multivariate principal component-discriminant analysis and artificial neural networks (anns). spectral patterns developed by discriminant analysis and tested with leave-one-out (lo ... | 2005 | 15767008 |
| salmonella invasion gene regulation: a story of environmental awareness. | salmonella enterica serovar typhimurium causes human gastroenteritis and a systemic typhoid-like infection in mice. a critical virulence determinant of salmonella is the ability to invade mammalian cells. the expression of genes required for invasion is tightly regulated by environmental conditions and a variety of regulatory genes. the hila regulator encodes an ompr/toxr family transcriptional regulator that activates the expression of invasion genes in response to both environmental and geneti ... | 2005 | 15765064 |
| class 1 integron-associated gene cassettes in salmonella enterica subsp. enterica serovar agona isolated from pig carcasses in brazil. | two multiresistant salmonella enterica subsp. enterica serovar agona isolates from pig carcasses were investigated for antimicrobial resistance genes and their location with particular reference to the detection of class 1 integrons. | 2005 | 15761062 |
| antiprotease inactivation by salmonella enterica released from infected macrophages. | the mammalian serine protease plasmin, which has an important role in extracellular matrix degradation during cell migration, is regulated by the plasma antiprotease alpha(2)-antiplasmin (alpha(2)ap). the surface protease pgte of salmonella enterica serovar typhimurium proteolytically inactivated alpha(2)ap. pgte also activates the plasma zymogen plasminogen to plasmin, and bacteria expressing pgte promoted degradation of extracellular matrix laminin in the presence of plasminogen and alpha(2)ap ... | 2005 | 15760453 |
| identification of the outer-membrane protein pagc required for the serum resistance phenotype in salmonella enterica serovar choleraesuis. | serum resistance is a crucial virulence factor for the development of systemic infections, including bacteraemia, by many pathogenic bacteria. salmonella enterica serovar choleraesuis is an important enteric pathogen that causes serious systemic infections in swine and humans. here, it was found that, when introduced into escherichia coli, a recombinant plasmid carrying the pagc gene from a plasmid-based genomic library of s. enterica serovar choleraesuis conferred a high-level resistance to the ... | 2005 | 15758232 |
| genome update: base skews in 200+ bacterial chromosomes. | 2005 | 15758208 | |
| effect of regulation and education on reptile-associated salmonellosis. | reptiles have become increasingly common as domestic pets, and with them reptile-associated salmonella infections in humans. from 1990 to 2000, a total of 339 reptile-associated salmonella cases were reported in sweden. in 1996, as part of its efforts to adapt its import regulations to those of the european union, sweden no longer required certificates stating that imported animals were free of salmonella. a subsequent increase was noted in the incidence of reptile-associated cases from 0.15/100 ... | 2005 | 15757554 |
| chitosan inactivates spoilage yeasts but enhances survival of escherichia coli o157:h7 in apple juice. | to develop new measures for controlling both spoilage and pathogenic micro-organisms in unpasteurized apple juice using chitosan. | 2005 | 15752333 |
| the salmonella genomic island 1 is an integrative mobilizable element. | salmonella genomic island 1 (sgi1) is a genomic island containing an antibiotic resistance gene cluster identified in several salmonella enterica serovars. the sgi1 antibiotic resistance gene cluster, which is a complex class 1 integron, confers the common multidrug resistance phenotype of epidemic s. enterica typhimurium dt104. the sgi1 occurrence in s. enterica serovars typhimurium, agona, paratyphi b, albany, meleagridis and newport indicates the horizontal transfer potential of sgi1. here, w ... | 2005 | 15752209 |
| ligand binding properties of bacterial hemoglobins and flavohemoglobins. | bacterial hemoglobins and flavohemoglobins share a common globin fold but differ otherwise in structural and functional aspects. the bases of these differences were investigated through kinetic studies on oxygen, carbon monoxide, and nitric oxide binding. the novel bacterial hemoglobins from clostridium perfringens and campylobacter jejuni and the flavohemoglobins from bacillus subtilis and salmonella enterica serovar typhi have been analyzed. examination of the biochemical and ligand binding pr ... | 2005 | 15751990 |
| synthesis and evaluation of mimetics of udp and udp-alpha-d-galactose, dtdp and dtdp-alpha-d-glucose with monosaccharides replacing the key pyrophosphate unit. | a series of 5'-o-glycosyl-uridine and thymidine derivatives have been prepared as potential mimics of sugar nucleotides and nucleotide-diphosphates. these compounds proved not to be inhibitors of bovine beta-1,4-galactosyltransferase although some showed moderate inhibition of salmonella dtdp-alpha-d-glucose 4,6-dehydratase (rmlb). | 2005 | 15750655 |
| typhoid fever associated with acute appendicitis caused by an h1-j strain of salmonella enterica serotype typhi. | while most strains of salmonella enterica serotype typhi, the etiologic agent of typhoid fever, have only a phase 1 flagellar antigen, h1-d, variations of the flagellar antigen have been observed. although h1-j strains (one of the flagellar antigen variants) account for 10 to 50% of s. enterica serotype typhi strains found in indonesia, there have been no published data to suggest its existence in other parts of the world. we describe a case of typhoid fever associated with acute appendicitis ca ... | 2005 | 15750137 |
| analysis of salmonella enterica serotype typhi pulsed-field gel electrophoresis patterns associated with international travel. | typhoid fever is a significant cause of morbidity and mortality worldwide, causing an estimated 16 million cases and 600,000 deaths annually. although overall rates of the disease have dramatically decreased in the united states, the number of travel-related infections has increased in recent decades. drug resistance among salmonella enterica serotype typhi strains has emerged worldwide, making antimicrobial susceptibility testing an important function in public health laboratories. pulsed-field ... | 2005 | 15750084 |
| vi antigen expression in salmonella enterica serovar typhi clinical isolates from pakistan. | the accurate identification of salmonella enterica subsp. enterica serovar typhi variants that fail to express the capsular polysaccharide, vi, is an important and much discussed issue for medical microbiology. we have tested a multiplex pcr method which shows the presence or absence of the genetic locus required for vi expression. of 2,222 salmonella serovar typhi clinical isolates collected from patients' blood over a 4-year period in a region of pakistan where typhoid is endemic, 12 tested ne ... | 2005 | 15750077 |
| nosocomial outbreak caused by salmonella enterica serotype livingstone producing ctx-m-27 extended-spectrum beta-lactamase in a neonatal unit in sousse, tunisia. | in this study, we report an outbreak of salmonella enterica serotype livingstone resistant to extended-spectrum cephalosporins that occurred in a neonatal ward of the maternity department of farhat hached hospital, sousse, tunisia, in 2002. a total of 16 isolates were recovered from 16 babies hospitalized in the ward during the period 1 to 16 july. all these babies developed diarrhea, and three of them developed septicemia. all the isolates demonstrated resistance to ceftriaxone and ceftazidime ... | 2005 | 15750057 |
| adhesion of bacteria to resected human colonic tissue: quantitative analysis of bacterial adhesion and viability. | adhesion to the intestinal mucosa is considered to be one of the main selection criteria of lactic acid bacteria for probiotic use. adhesive probiotics are, for example, considered to provide better antagonism against pathogenic bacteria when compared to non-adhesive strains. here a new model is described for studying adhesion and interaction of probiotic and pathogenic bacteria in the intestinal mucus in which the intestinal microbiota is present. the model is based on the use of human intestin ... | 2005 | 15748990 |
| host susceptibility and clinical outcomes in toll-like receptor 5-deficient patients with typhoid fever in vietnam. | toll-like receptor 5 (tlr5) mediates innate immune responses to bacterial pathogens by binding to flagellin. a polymorphism in the tlr5 gene introduces a premature stop codon (tlr5(392stop)) that is associated with susceptibility to legionnaires disease. here we investigated whether tlr5(392stop) was associated with typhoid fever. the frequency of tlr5(392stop) was not significantly different in 565 patients with typhoid fever and 281 ethnically matched control subjects. furthermore, tlr5 defici ... | 2005 | 15747241 |
| genomic comparisons of salmonella enterica serovar dublin, agona, and typhimurium strains recently isolated from milk filters and bovine samples from ireland, using a salmonella microarray. | salmonella-induced enterocolitis is the leading food-borne illness with a lethal outcome and causes millions of cases of gastroenteritis each year. we examined genomic variation among 12 environmental, veterinary, and clinical salmonella enterica serovar dublin, agona, and typhimurium strains isolated in ireland between 2000 and 2003, as well as two clinical isolates from canada and four archival isolates, which belonged to serovars dublin and agona. using dna-dna hybridization to a microarray c ... | 2005 | 15746367 |
| enhanced survival of salmonella enterica in vesicles released by a soilborne tetrahymena species. | nondestructive ingestion by soilborne protozoa may enhance the environmental resiliency of important bacterial pathogens and may model how such bacteria evade destruction in human macrophages. here, the interaction of salmonella enterica serovar thompson with a soilborne tetrahymena sp. isolate was examined using serovar thompson cells labeled with the green fluorescent protein. the bacteria were mixed in solution with cells of tetrahymena at several ratios. during incubation with serovar thomps ... | 2005 | 15746361 |
| acquisition of resistance to extended-spectrum cephalosporins by salmonella enterica subsp. enterica serovar newport and escherichia coli in the turkey poult intestinal tract. | salmonella enterica subsp. enterica serovar newport resistant to the extended-spectrum cephalosporins (escs) and other antimicrobials causes septicemic salmonellosis in humans and animals and is increasingly isolated from humans, animals, foods, and environmental sources. mechanisms whereby serovar newport bacteria become resistant to escs and other classes of antimicrobials while inhabiting the intestinal tract are not well understood. the present study shows that 25.3% of serovar newport strai ... | 2005 | 15746317 |
| effect of heat, acidification, and chlorination on salmonella enterica serovar typhimurium cells in a biofilm formed at the air-liquid interface. | bacterial biofilms have great significance for public health, since biofilm-associated microorganisms exhibit dramatically decreased susceptibility to antimicrobial agents and treatments. to date most attention has focused on biofilms that arise from the colonization of solid-liquid or solid-air interfaces. it is of interest that colonization of the interface between air and liquid, which can be selectively advantageous for aerobic or facultative aerobic bacteria, has been rarely studied, althou ... | 2005 | 15746314 |
| temperature sensitive mutation in the 38 kda minor structural protein gene of phage mb78 interferes with phage morphogenesis. | temperature sensitive mutation in the gene for the 38 kda minor structural protein of the phage mb78, a virulent phage of salmonella enterica serovar typhimurium, interferes with phage development at restrictive temperature. electron microscopy of particles produced at non-permissive temperature indicated that the particles formed are tailless. two types of particles are seen: (i) empty capsids, which are not perfect icosahedral (ii) icosahedral particles filled with dna. the gene for the 38 kda ... | 2005 | 15744577 |
| cyclic amp (camp) and camp receptor protein influence both synthesis and uptake of extracellular autoinducer 2 in escherichia coli. | bacterial autoinducer 2 (ai-2) is proposed to be an interspecies mediator of cell-cell communication that enables cells to operate at the multicellular level. many environmental stimuli have been shown to affect the extracellular ai-2 levels, carbon sources being among the most important. in this report, we show that both ai-2 synthesis and uptake in escherichia coli are subject to catabolite repression through the cyclic amp (camp)-crp complex, which directly stimulates transcription of the lsr ... | 2005 | 15743955 |
| nucleotide sequence of the head assembly gene cluster of bacteriophage l and decoration protein characterization. | the temperate salmonella enterica bacteriophage l is a close relative of the very well studied bacteriophage p22. in this study we show that the l procapsid assembly and dna packaging genes, which encode terminase, portal, scaffold, and coat proteins, are extremely close relatives of the homologous p22 genes (96.3 to 99.1% identity in encoded amino acid sequence). however, we also identify an l gene, dec, which is not present in the p22 genome and which encodes a protein (dec) that is present on ... | 2005 | 15743953 |
| percolation of the phd repressor-operator interface. | transcription of the p1 plasmid addiction operon, a prototypical toxin-antitoxin system, is negatively autoregulated by the products of the operon. the phd repressor-antitoxin protein binds to 8-bp palindromic phd-binding sites in the promoter region and thereby represses transcription. the toxin, doc, mediates cooperative interactions between adjacent phd-binding sites and thereby enhances repression. here, we describe a homologous operon from salmonella enterica serovar typhimurium which has t ... | 2005 | 15743936 |
| reduction of salmonella enterica serovar enteritidis colonization and invasion by an alfalfa diet during molt in leghorn hens. | the standard method for molting to stimulate multiple egg-laying cycles in laying hens is feed deprivation. however, the physiological changes within hens caused by feed deprivation increase susceptibility of the hens to salmonella enterica serovar enteritidis (se) infection. in an effort to develop an alternative method to induce molting without increasing susceptibility to se, an alfalfa diet was compared with the standard molting method for the level of ovary regression and se colonization. h ... | 2005 | 15742953 |
| genetically engineered production of 1-desmethylcobyrinic acid, 1-desmethylcobyrinic acid a,c-diamide, and cobyrinic acid a,c-diamide in escherichia coli implies a role for cbid in c-1 methylation in the anaerobic pathway to cobalamin. | co-expression of the coba gene from propionibacterium freudenreichii and the cbia, -c, -d, -e, -t, -f, -g, -h, -j, -k, -l, and -p genes from salmonella enterica serovar typhimurium in escherichia coli resulted in the production of cobyrinic acid a,c-diamide. a cbid deletion mutant of this strain produced 1-desmethylcobyrinic acid a,c-diamide, indicating that cbid is involved in c-1 methylation in the anaerobic pathway to cobalamin. strains that did not have the cbip gene also produced 1-desmethy ... | 2005 | 15741157 |
| occurrence of multi-resistant salmonella enterica typhimurium dt 104 in austria isolated from humans, animals and food. | 2005 | 15737526 | |
| multidrug resistance in salmonella enterica serovar typhi isolated from patients with typhoid fever complications in lagos, nigeria. | the aim of this study was to determine the prevalence of salmonella enterica serovar typhi in patients with pyrexia of unknown origin (puo), and antimicrobial resistance in strains isolated from patients with s. typhi in lagos, nigeria. | 2005 | 15733694 |