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phase variation of a beta-1,3 galactosyltransferase involved in generation of the ganglioside gm1-like lipo-oligosaccharide of campylobacter jejuni.ganglioside mimicry by campylobacter jejuni lipo-oligosaccharide (los) is thought to be a critical factor in the triggering of the guillain-barré and miller-fisher syndrome neuropathies after c. jejuni infection. the combination of a completed genome sequence and a ganglioside gm1-like los structure makes c. jejuni nctc 11168 a useful model strain for the identification and characterization of the genes involved in the biosynthesis of ganglioside-mimicking los. genome analysis identified a putat ...200010931344
activity of antibiotics used in human medicine for campylobacter jejuni isolated from farm animals and their environment in lancashire, uk.a retrospective study of 96 campylobacter jejuni isolated from farm animals and the environment showed that most were less susceptible than the nctc type strain to nalidixic acid (mics 4-32 mg/l), ciprofloxacin (mics 1-2 mg/l) and erythromycin (mics 16-64 mg/l), but had similar susceptibility to tetracycline (mics 4-8 mg/l) and kanamycin (mics 4-8 mg/l). none had the high mics of ciprofloxacin (>32 mg/l) or erythromycin (1024 mg/l) typically associated with clinical resistance in this species. s ...200010933658
campylobacter infection of commercial poultry.campylobacter jejuni, a widespread food-borne pathogen is responsible for enteritis in the populations of both industrialised and developing nations and is acquired by consumption of contaminated water, milk and food products. contaminated poultry meat is regarded as an important source of campylobacteriosis, with both commercial broiler and turkey growing flocks infected at two to three weeks of age by direct and indirect horizontal exposure. non-chlorinated water is regarded as a vehicle of in ...200010935269
ostrich diseases.scientific knowledge of ostrich diseases is incomplete and very fragmented, with specific details on technical aspects of diagnostic and/or screening tests completely absent in most cases. salmonella typhimurium is common in multispecies collections and causes mortality in chicks younger than three months on commercial farms, but is rarely found in chicks older than six months, or slaughter birds of twelve to fourteen months in southern africa. campylobacter jejuni and chlamydia psittaci are occ ...200010935285
rapid detection of salmonella typhimurium in chicken carcass wash water using an immunoelectrochemical method.an immunoelectrochemical method coupled with immunomagnetic separation was developed for rapid detection of salmonella typhimurium in chicken carcass wash water. samples of chicken carcass wash water were inoculated with salmonella typhimurium at different cell numbers. possible nonspecified inhibitors in the wash water were minimized by filtration and centrifugation. an approximately 9.4% loss of salmonella cells was found after filtration (p < 0.01). the samples were mixed with anti-salmonella ...200010945578
expression of the cytolethal distending toxin (cdt) operon in actinobacillus actinomycetemcomitans: evidence that the cdtb protein is responsible for g2 arrest of the cell cycle in human t cells.we have previously shown that actinobacillus actinomycetemcomitans produces an immunosuppressive factor that is encoded by the cdtb gene, which is homologous to a family of cytolethal distending toxins (cdt) expressed by several gram-negative bacteria. in this study, we report that the cdt locus in a. actinomycetemcomitans is composed of five open reading frames, designated orf1, orf2, cdta, cdtb, and cdtc. the deduced amino acid sequences of the five open reading frames are highly conserved amo ...200010946289
chronic helicobacter pylori infection induces an apoptosis-resistant phenotype associated with decreased expression of p27(kip1).helicobacter pylori infection is associated with the development of gastric cancer. in short-term coculture with ags gastric cells, h. pylori inhibits cell cycle progression and induces dose-dependent apoptosis. based on the concept that an imbalance between proliferation and apoptosis may contribute to the emergence of gastric cancer, we chronically exposed ags cells to h. pylori as a model of chronic exposure in humans. the ags derivatives selected by this process were stably resistant not onl ...200010948161
neisseria gonorrhoeae elicits membrane ruffling and cytoskeletal rearrangements upon infection of primary human endocervical and ectocervical cells.neisseria gonorrhoeae is a strict human pathogen that is, primarily, transmitted by close sexual contact with an infected individual. gonococcal infection of the male urogenital tract has been well studied in experimental human models and in urethral cell culture systems. recent studies, using tissue culture cell systems, have suggested a role for the cervical epithelium in gonococcal infection of females; however, the nature of gonococcal infection of the normal uterine cervix remains controver ...200010948165
random transposon mutagenesis of campylobacter jejuni.genetic studies of campylobacter jejuni have been limited due to the lack of a transposon mutagenesis method. here, we describe a novel technique for random transposon mutagenesis using a mariner-based transposon into c. jejuni strain 480. insertions were random, as demonstrated by southern blot analysis and insertional junction sequencing. we have demonstrated, for the first time, random in vivo transposon mutagenesis of c. jejuni.200010948182
is campylobacter lipopolysaccharide bearing a gd3 epitope essential for the pathogenesis of guillain-barré syndrome?the hypothesis has been proposed that the gd3 ganglioside-like lipopolysaccharide (lps) is essential for and functions in the development of guillain-barré syndrome (gbs) and miller fisher syndrome (mfs) subsequent to campylobacter jejuni enteritis. our study showed that patients with gbs or mfs who had previously suffered diarrhea had anti-gd3 antibodies less often than those who had not had diarrhea. sera from patients who showed gbs or mfs with the serologic evidence of prior c. jejuni infect ...200010949532
functional analysis of putative restriction-modification system genes in the helicobacter pylori j99 genome.helicobacter pylori is a gram-negative bacterium, which colonizes the gastric mucosa of humans and is implicated in a wide range of gastroduodenal diseases. the genomic sequences of two h.pylori strains, 26695 and j99, have been published recently. about two dozen potential restriction-modification (r-m) systems have been annotated in both genomes, which is far above the average number of r-m systems in other sequenced genomes. here we describe a functional analysis of the 16 putative type ii r- ...200010954588
re-annotating the mycoplasma pneumoniae genome sequence: adding value, function and reading frames.four years after the original sequence submission, we have re-annotated the genome of mycoplasma pneumoniae to incorporate novel data. the total number of orfss has been increased from 677 to 688 (10 new proteins were predicted in intergenic regions, two further were newly identified by mass spectrometry and one protein orf was dismissed) and the number of rnas from 39 to 42 genes. for 19 of the now 35 trnas and for six other functional rnas the exact genome positions were re-annotated and two n ...200010954595
detection and investigation of campylobacter jejuni by polymerase chain reaction-restriction fragment length polymorphism analysis.a molecular typing approach for campylobacter jejuni with restriction fragment length polymorphism (rflp) analysis of the flagellin gene flaa in c. jejuni, was generated and studied. using polymerase chain reaction (pcr)-rflp with the restriction endonuclease mbo i, it was demonstrated that c. jejuni could be divided into four types. genotypic analysis of c. jejuni by pcr-rflp is a valuable technique for epidemiological typing.200010955830
lipopolysaccharides in the development of the guillain-barré syndrome and miller fisher syndrome forms of acute inflammatory peripheral neuropathies.guillain-barré syndrome (gbs), an acute inflammatory polyneuropathy, is preceded in most cases by an infectious illness, and campylobacter jejuni, a leading cause of acute gastroenteritis, is the most common antecedent to gbs and its ocular variant, miller fisher syndrome (mfs). o (penner) serotyping is considered to distinguish between c. jejuni strains based on differences in lipopolysaccharide (lps) structure. serotypes of c. jejuni uncommon in enteritis, such as serotype o:19 and o:41, have ...200011521055
[experimental study on an animal model of axonal form guillain-barre syndrome].to investigate an animal model of axonal form guillain-barre syndrome (gbs).200011236637
campylobacter jejuni bacteremia, peritonitis, and exacerbation of chronic pancreatitis in a patient on capd: case report and literature review. 200011216580
the genome sequence of the food-borne pathogen campylobacter jejuni reveals hypervariable sequences.campylobacter jejuni, from the delta-epsilon group of proteobacteria, is a microaerophilic, gram-negative, flagellate, spiral bacterium-properties it shares with the related gastric pathogen helicobacter pylori. it is the leading cause of bacterial food-borne diarrhoeal disease throughout the world. in addition, infection with c. jejuni is the most frequent antecedent to a form of neuromuscular paralysis known as guillain-barré syndrome. here we report the genome sequence of c. jejuni nctc11168. ...200010688204
diet influences the colonisation of campylobacter jejuni and distribution of mucin carbohydrates in the chick intestinal tract.the objectives of this study were to evaluate the effect of diet on the colonisation by campylobacter jejuni of the chick caeca, and to determine whether the viscosity of the intestinal contents and mucin carbohydrates were altered by the diet. the diets investigated were maize based, wheat-based or wheat-based supplemented with xylanase. the xylanase-supplemented diet reduced the viscosity and lowered the numbers of camp. jejuni. feeding the enzyme-supplemented diet increased the amount of neut ...200011130183
current cases in which epitope mimicry is considered a component cause of autoimmune disease: guillain-barré syndrome.some patients develop guillain-barré syndrome (gbs) after the administration of bovine gangliosides. patients with gbs subsequent to campylobacter jejuni enteritis frequently have igg antibody to gm1 ganglioside. miller fisher syndrome (mfs), a variant of gbs, is associated with igg antibody to gq1b ganglioside. molecular mimicry between gm1 and lipopolysaccharide of c. jejuni isolated from patients with gbs, and between gq1b and c. jejuni lipopolysaccharides from patients with mfs have been dem ...200011130452
campylobacter contamination of raw meat and poultry at retail sale: identification of multiple types and comparison with isolates from human infection.campylobacter species are the major cause of acute bacterial enteritis reported in the united kingdom, nonetheless many aspects of campylobacteriosis epidemiology remain poorly understood. the aim of this study was to determine the prevalence of campylobacter jejuni and campylobacter coli in fresh bovine, ovine, and porcine liver and chicken portions from retail outlets and compare strain subtype distributions with those associated with cases of human campylobacteriosis occurring within the same ...200011131886
essential role of glu-c66 for menaquinol oxidation indicates transmembrane electrochemical potential generation by wolinella succinogenes fumarate reductase.quinol:fumarate reductase (qfr) is a membrane protein complex that couples the reduction of fumarate to succinate to the oxidation of quinol to quinone, in a reaction opposite to that catalyzed by the related enzyme succinate:quinone reductase (succinate dehydrogenase). in the previously determined structure of qfr from wolinella succinogenes, the site of fumarate reduction in the flavoprotein subunit a of the enzyme was identified, but the site of menaquinol oxidation was not. in the crystal st ...200011186225
detection of thermophilic campylobacter from sparrows by multiplex pcr: the role of sparrows as a source of contamination of broilers with campylobacter.the best combination of primers and the annealing temperature of multiplex pcr for campylobacter jejuni, campylobacter coli, and campylobacter lari were examined. the multiplex pcr was able to detect type strains of the three species. all results of identification of wild strains (30 strains of c. jejuni, 20 strains of c. coli, and 4 strains of c. lari) by the multiplex pcr coincided with those of the conventional biochemical identification tests, suggesting that the multiplex pcr can simultaneo ...200011193345
genotyping campylobacter jejuni strains isolated from the gut and oviduct of laying hens.campylobacter jejuni frequently colonizes the avian intestine. recent evidence suggests that this organism can also colonize the oviduct of laying hens. however, the source and role of this colonization are unknown. isolates from the ceca, cloacae, and oviducts of 11 laying hens in three intensive egg-producing flocks were genotyped by fla typing with the restriction fragment length polymorphism of the polymerase chain reaction product of the flaa and flab genes (fla typing) and pulsed-field gel ...200011195647
sequential spread of campylobacter infection in a multipen broiler house.generally, colonization with campylobacter jejuni is first detected in broilers 2-3 wk after hatching. once introduced into a flock, this infection spreads very rapidly. the sources and routes of transmission of c. jejuni in broilers remain debatable. in this study, the spread of infection was monitored in a commercial multipen broiler house in which birds were contained in discrete groups and sampled sequentially. colonization was monitored in two broiler flocks up to slaughter. serotyping and ...200011195658
national surveillance of campylobacter in broilers at slaughter in denmark in 1998.a surveillance study for thermophilic campylobacter spp. in broiler flocks was carried out for the year 1998 in denmark. the study included examinations of 4286 broiler flocks comprising samples from 57,000 birds. overall, a flock prevalence of 46.0% was recorded. the species distribution was campylobacter jejuni 86%, campylobacter coli 11%, campylobacter lari 1%, other not further diagnosed species 2%. the prevalence was significantly higher in the period from june to october (3.2 < odds ratio ...200011195660
plasma cytokine response in mice with bacterial infection.exposure to microorganisms elicts the production of cytokines. these soluble factors enhance several innate immune functions and regulate the ensuing specific immune response aimed at limiting the spread of infection.200011200363
a rapid dna isolation procedure for the identification of campylobacter jejuni by the polymerase chain reaction.we have developed an efficient process for rapidly isolating campylobacter dna using mechanical disruption combined with the guanidine-based reagent dnazol. template dna was isolated by this method from cultures of campylobacter jejuni resistant to lysis by boiling or enzymes and identified following polymerase chain reaction (pcr) amplification using primers specific for the hippuricase gene. direct detection of campylobacters in poultry-processing samples by pcr is demonstrated in chicken carc ...200011123549
evaluation of a new commercial immunoassay for rapid detection of campylobacter jejuni in stool samples.in order to evaluate a new commercial enzyme immunoassay (prospect campylobacter microplate assay; alexon-trend, usa) for the detection of campylobacter jejuni and campylobacter coli in stool samples, 30 faecal specimens known to be culture-positive for campylobacter jejuni were tested with the new assay. the detection limit was approximately 3 x 10(6)/ml in faecal suspensions. the sensitivity relative to culture was 80% (24/30). all of the 24 positive samples, except for one, remained positive ...200011117647
a waterborne outbreak of small round structured virus, campylobacter and shigella co-infections in la neuveville, switzerland, 1998.an outbreak of gastro-enteritis occurred in la neuveville, township with 3358 inhabitants. a retrospective cohort study of 1915 participants showed that 1607 (84%) had been ill. campylobacter jejuni was isolated from 28 patient faecal samples, shigella sonnei from 21 patients and small round structured viruses (srsv) from 6 patients. more than one pathogen was identified in eight persons. the epidemic curve was characteristic of a point-source outbreak. the risk for illness was significantly hig ...200011117956
antimicrobial resistance profiling and dna amplification fingerprinting (daf) of thermophilic campylobacter spp. in human, poultry and porcine samples from the cork region of ireland.antimicrobial resistance (r) typing and dna amplification fingerprinting (daf) of a random collection of 84 irish thermophilic campylobacter isolates is described. the collection included human, veterinary (porcine) and poultry isolates cultured between 1996 and 1998 in the cork region of ireland. biochemical and molecular methods were used to identify campylobacter jejuni and camp. coli. many of these isolates were simultaneously resistant to several common antimicrobial agents. in particular, ...200011119145
the effect of thermal stress on campylobacter coli.enteropathogenic campylobacter jejuni, camp. coli and camp. lari are currently the most common cause of acute infectious diarrhoeal illness in the uk. many domestic animals, including pigs, act as natural reservoirs for these organisms and infection may occur through the ingestion of contaminated foodstuffs. the safety of locally produced porcine liver was assessed in relation to the heat susceptibility of campylobacter spp. present in eviscerated product.200011119166
comparison of basal broth media for the optimal laboratory recovery of campylobacter jejuni and campylobacter coli.campylobacter species are the most common known bacterial cause of acute diarrhoeal disease and incidences are increasing yearly in ireland. concern is expressed that this increase may be due to poor laboratory techniques in recognising these organisms as they are fastidious and technically demanding to culture.200011272874
hla alleles in patients with guillain-barre syndrome.to determine whether genetic factors may work in concert with autoimmune factors in the pathogenesis of guillain-barre syndrome (gbs).200011776098
cytolethal distending toxin sequence and activity in the enterohepatic pathogen helicobacter hepaticus.little is known about the molecular pathogenesis of hepatitis and enterocolitis caused by enterohepatic helicobacter species. sonicates of the murine pathogen helicobacter hepaticus were found to cause progressive cell distension, accumulation of filamentous actin, and g(2)/m cell cycle arrest in hela cell monolayers. the genes encoding this cytotoxic activity were cloned from h. hepaticus. three open reading frames with closest homology to cdta, cdtb, and cdtc from campylobacter jejuni were ide ...200010603386
detection of antibodies against campylobacter jejuni serogroup pen o:19 purified flagellar protein in a patient with guillain-barré syndrome.c. jejuni serogroup pen o:19 was isolated from a stool specimen from a patient with guillain-barré syndrome (gbs). flagellar protein was isolated and purified from reference strain c. jejuni pen o:19, atcc 43,446, as well as from a homologous patient strain. antibodies against flagellar protein were detected by means of immunoblotting, enzyme-linked immunosorbent assay (elisa) and tube agglutination test. the antibody titres were found to be directly correlated at the beginning and in the recove ...199910603661
a phylogenomic study of dna repair genes, proteins, and processes.the ability to recognize and repair abnormal dna structures is common to all forms of life. studies in a variety of species have identified an incredible diversity of dna repair pathways. documenting and characterizing the similarities and differences in repair between species has important value for understanding the origin and evolution of repair pathways as well as for improving our understanding of phenotypes affected by repair (e.g., mutation rates, lifespan, tumorigenesis, survival in extr ...199910606811
dose response and organ invasion of day-of-hatch leghorn chicks by different isolates of campylobacter jejuni.colonization of the ceca and organ invasion by different isolates of campylobacter jejuni were investigated in day-of-hatch leghorn chicks. this model of campylobacter colonization of the ceca demonstrates that 1) day-of-hatch birds do not naturally contain cecal campylobacter, 2) ceca can be colonized with c. jejuni by oral gavage and not by cloacal inoculation; 3) c. jejuni can be recovered from the ceca up until at least 7 days postinoculation, 4) cecal colonization occurs when as little as 1 ...199910611992
severe guillain-barré syndrome associated with campylobacter jejuni infection. 199910612373
procedure for the investigation of bacterial genomes: random shot-gun cloning, sample sequencing and mutagenesis of campylobacter jejuni. 19999894591
molecular epidemiology of campylobacter jejuni in broiler flocks using randomly amplified polymorphic dna-pcr and 23s rrna-pcr and role of litter in its transmission.poultry has long been cited as a reservoir for campylobacter spp., and litter has been implicated as a vehicle in their transmission. chicks were raised on litter removed from a broiler house positive for campylobacter jejuni. litter was removed from the house on days 0, 3, and 9 after birds were removed for slaughter. chicks were raised on these three litters under controlled conditions in flocks of 25. none of these birds yielded c. jejuni in their cecal droppings through 7 weeks. two successi ...19999872787
use of genomics to identify bacterial undecaprenyl pyrophosphate synthetase: cloning, expression, and characterization of the essential upps gene.the prenyltransferase undecaprenyl pyrophosphate synthetase (di-trans,poly-cis-decaprenylcistransferase; ec 2.5.1.31) was purified from the soluble fraction of escherichia coli by tsk-deae, ceramic hydroxyapatite, tsk-ether, superdex 200, and heparin-actigel chromatography. the protein was labeled with the photolabile analogue of the farnesyl pyrophosphate analogue (e, e)-[1-3h]-(2-diazo-3-trifluoropropionyloxy)geranyl diphosphate and was detected on a sodium dodecyl sulfate-polyacrylamide gel a ...19999882662
motility of helicobacter pylori is coordinately regulated by the transcriptional activator flgr, an ntrc homolog.sigma54 is the subunit of bacterial rna polymerase that transcribes from promoters with enhancer elements bound by enhancer-binding proteins. by computer searches of helicobacter pylori genomic sequences, chromosomal gene disruption, and rna analyses, we have identified sigma54-recognized promoters that regulate transcription of flagellar basal body and hook genes, as well as the enhancer-binding protein flgr (flagellum regulator), a transactivating protein of the ntrc family. we demonstrate tha ...19999882675
the cytolethal distending toxin from the chancroid bacterium haemophilus ducreyi induces cell-cycle arrest in the g2 phase.the potent cytolethal distending toxin produced by haemophilus ducreyi is a putative virulence factor in the pathogenesis of chancroid. we studied its action on eukaryotic cells, with the long-term goal of understanding the pathophysiology of the disease. intoxication of cultured human epithelial-like cells, human keratinocytes, and hamster fibroblasts was irreversible, and appeared as a gradual distention of three- to fivefold the size of control cells. organized actin assemblies appeared conco ...19999884340
pcr-enzyme-linked immunosorbent assay for detection and identification of campylobacter species: application to isolates and stool samples.we report a pcr-enzyme-linked immunosorbent assay which identifies campylobacter species by capture hybridization of a single-stranded 16s rrna gene amplicon with species-specific probes in a microtiter plate format. specificities were confirmed for both reference and field strains, but the type strain of campylobacter coli was atypical. the assay was rapid, informative, and usable with stool-extracted dna.19999889235
campylobacter jejuni-stimulated secretion of interleukin-8 by int407 cells.incubation of int407 cells with various clinical isolates of campylobacter jejuni resulted in secretion of interleukin-8 (il-8) at levels ranging from 96 to 554 pg/ml at 24 h. the strains which produced the highest levels of il-8 secretion were 81-176 and bt44. induction of il-8 secretion required live cells of 81-176 and was dependent on de novo protein synthesis. site-specific mutants of 81-176, which were previously shown to be defective in adherence and invasion, resulted in reduced levels o ...19999864200
cloning and characterization of a novel membrane-associated antigenic protein of helicobacter pylori.infection by helicobacter pylori, a noninvasive bacterium, induces chronic leukocyte infiltration in the stomach by still largely unknown molecular mechanisms. we investigated the possibility that a membrane protein of h. pylori induces an inflammatory reaction in the subepithelial tissue of the stomach. by generating an expression library of h. pylori chromosomal dna and screening with rabbit antiserum raised to a membrane fraction of h. pylori and sera of infected patients, we cloned a 16.0-kd ...19999864228
response to reactive nitrogen intermediates in mycobacterium tuberculosis: induction of the 16-kilodalton alpha-crystallin homolog by exposure to nitric oxide donors.in contrast to the apparent paucity of mycobacterium tuberculosis response to reactive oxygen intermediates, this organism has evolved a specific response to nitric oxide challenge. exposure of m. tuberculosis to no donors induces the synthesis of a set of polypeptides that have been collectively termed nox. in this work, the most prominent nox polypeptide, nox16, was identified by immunoblotting and by n-terminal sequencing as the alpha-crystallin-related, 16-kda small heat shock protein, shsp1 ...19999864257
sequence diversity of flagellin (flic) alleles in pathogenic escherichia coli.to study the molecular evolution of flagellin, the protein subunit specifying flagellar (h) antigens, the flic genes from 15 pathogenic strains of escherichia coli were amplified by pcr and sequenced. comparison of flic sequences of h6 and h7 strains revealed that alleles have a mosaic structure indicating the occurrence of past horizontal transfer of dna segments between strains. the close similarity of h7 sequences also indicates the exchange of an entire flic h7 allele between distant clonal ...19999864325
type ii topoisomerase mutations in ciprofloxacin-resistant strains of pseudomonas aeruginosa.we determined the sequences of the quinolone resistance-determining regions of gyra, gyrb, and parc genes for 30 clinical strains of pseudomonas aeruginosa resistant to ciprofloxacin that were previously complemented by wild-type gyra and gyrb plasmid-borne alleles and studied for their coresistance to imipenem (e. cambau, e. perani, c. dib, c. petinon, j. trias, and v. jarlier, antimicrob. agents chemother. 39:2248-2252, 1995). in the present study, we found mutations in type ii topoisomerase g ...19999869566
toxic megacolon associated with campylobacter jejuni colitis. 19999934778
identification of the enteropathogens campylobacter jejuni and campylobacter coli based on the cadf virulence gene and its product.campylobacter jejuni and campylobacter coli are common causes of gastroenteritis in humans. infection with c. jejuni or c. coli is commonly acquired by eating undercooked chicken. the goal of this study was to develop specific detection assays for c. jejuni and c. coli isolates based on the cadf virulence gene and its product. the cadf gene from c. jejuni and c. coli encodes a 37-kda outer membrane protein that promotes the binding of these pathogens to intestinal epithelial cells. a fragment of ...19999986804
body lice as tools for diagnosis and surveillance of reemerging diseases.body lice are vectors of three bacteria which cause human disease: rickettsia prowazekii, the agent of epidemic typhus; bartonella quintana, the agent of trench fever; and borrelia recurrentis, the agent of relapsing fever. a recrudescence of body lice is being observed as the numbers of individuals living under social conditions which predispose individuals to infestation have increased. because this phenomenon may lead to the reemergence of infections transmitted by body lice, we aimed to asse ...19999986818
identification and characterisation of a cytotoxic porin-lipopolysaccharide complex from campylobacter jejuni.a clinical isolate of campylobacter jejuni, previously found to produce a toxin active in cell culture assays, was used for identification and characterisation of a cytotoxic porin-lipopolysaccharide (lps) complex. this cytotoxic complex was isolated by high-performance liquid chromatography of crude concentrated culture supernate and deae-anion exchange chromatography. the complex had a toxic activity of 20.1 tissue culture dose50 (tcd50)/microg of protein for hep-2 cells, 7.49 tcd50/microg of ...19999989641
quorum sensing in escherichia coli, salmonella typhimurium, and vibrio harveyi: a new family of genes responsible for autoinducer production.in bacteria, the regulation of gene expression in response to changes in cell density is called quorum sensing. quorum-sensing bacteria produce, release, and respond to hormone-like molecules (autoinducers) that accumulate in the external environment as the cell population grows. in the marine bacterium vibrio harveyi two parallel quorum-sensing systems exist, and each is composed of a sensor-autoinducer pair. v. harveyi reporter strains capable of detecting only autoinducer 1 (ai-1) or autoindu ...19999990077
cloning and expression of the dnak gene of campylobacter jejuni and antigenicity of heat shock protein 70.campylobacter jejuni is a leading cause of infectious diarrhea throughout the world. in addition, there is growing evidence that guillain-barré syndrome, an inflammatory demyelinating disease of the peripheral nervous system, is frequently preceded by c. jejuni infection. in the present study, the hrca-grpe-dnak gene cluster of c. jejuni was cloned and sequenced. the dnak gene consists of an open reading frame of 1,869 bp and encodes a protein with a high degree of homology to other bacterial 70 ...199910024560
identification of a cytolethal distending toxin gene locus and features of a virulence-associated region in actinobacillus actinomycetemcomitans.a genetic locus for a cytolethal distending toxin (cdt) was identified in a polymorphic region of the chromosome of actinobacillus actinomycetemcomitans, a predominant oral pathogen. the locus was comprised of three open reading frames (orfs) that had significant amino acid sequence similarity and more than 90% sequence identity to the cdtabc genes of some pathogenic escherichia coli strains and haemophilus ducreyi, respectively. sonic extracts from recombinant e. coli, containing the a. actinom ...199910024565
characterization of human bactericidal antibodies to bordetella pertussis.the bordetella pertussis brka protein protects against the bactericidal activity of complement and antibody; however, some individuals mount an immune response that overcomes this bacterial defense. to further characterize this process, the bactericidal activities of sera from 13 adults with different modes of exposure to b. pertussis (infected as adults, occupational exposure, immunized with an acellular vaccine, or no identified exposure) against a wild-type strain and a brka complement-sensit ...199910024590
inducing enterotoxigenic properties in campylobacter jejuni and campylobacter coli by serial intraperitoneal passage in mice. 199910029919
etiology of outpatient pediatric nondysenteric diarrhea: a multicenter study in the united states.few data have been published recently on the etiology of outpatient pediatric diarrhea in the us.199910048678
lymphocytic colitis: a clue to an infectious trigger.we present a 19-year-old patient who was admitted for evaluation of prolonged watery diarrhea. previous study showed one stool culture positive for campylobacter jejuni, which was treated with appropriate antibiotics with no response. she underwent colonoscopy with multiple biopsies, which led to a diagnosis of lymphocytic colitis. we believe that the patient's disease was due to the infectious process, which triggered an autoimmune response and caused the lymphocytic colitis.199910048742
ferritin mutants of escherichia coli are iron deficient and growth impaired, and fur mutants are iron deficient.escherichia coli contains at least two iron storage proteins, a ferritin (ftna) and a bacterioferritin (bfr). to investigate their specific functions, the corresponding genes (ftna and bfr) were inactivated by replacing the chromosomal ftna and bfr genes with disrupted derivatives containing antibiotic resistance cassettes in place of internal segments of the corresponding coding regions. single mutants (ftna::spc and bfr::kan) and a double mutant (ftna::spc bfr::kan) were generated and confirme ...199910049371
physiological characterization of viable-but-nonculturable campylobacter jejuni cells.campylobacter jejuni is a pathogenic, microaerophilic, gram-negative, mesophilic bacterium. three strains isolated from humans with enteric campylobacteriosis were able to survive at high population levels (10(7) cells ml-1) as viable-but-nonculturable (vbnc) forms in microcosm water. the vbnc forms of the three c. jejuni strains were enumerated and characterized by using 5-cyano-2,3-ditolyl tetrazolium chloride-4',6-diamino-2-phenylindole staining. cellular volume, adenylate energy charge, inte ...199910049870
comparison of flagellin genes from clinical and environmental pseudomonas aeruginosa isolates.pseudomonas aeruginosa, an important opportunistic pathogen, was isolated from environmental samples and compared to clinically derived strains. while p. aeruginosa was isolated readily from an experimental mushroom-growing unit, it was found only rarely in other environmental samples. a flagellin gene pcr-restriction fragment length polymorphism analysis of the isolates revealed that environmental and clinical p. aeruginosa strains are not readily distinguishable. the variation in the central r ...199910049879
a randomly amplified polymorphic dna marker specific for the bacillus cereus group is diagnostic for bacillus anthracis.aiming to develop a dna marker specific for bacillus anthracis and able to discriminate this species from bacillus cereus, bacillus thuringiensis, and bacillus mycoides, we applied the randomly amplified polymorphic dna (rapd) fingerprinting technique to a collection of 101 strains of the genus bacillus, including 61 strains of the b. cereus group. an 838-bp rapd marker (sg-850) specific for b. cereus, b. thuringiensis, b. anthracis, and b. mycoides was identified. this fragment included a putat ...199910049896
in situ analysis of phototrophic sulfur bacteria in the chemocline of meromictic lake cadagno (switzerland).comparative sequence analysis of a 16s rrna gene clone library from the chemocline of the meromictic lake cadagno (switzerland) revealed the presence of a diverse number of phototrophic sulfur bacteria. sequences resembled those of rrna of type strains chromatium okenii dsm169 and amoebobacter purpureus dsm4197, as well as those of four bacteria forming a tight cluster with a. purpureus dsm4197 and lamprocystis roseopersicina dsm229. in situ hybridization with fluorescent (cy3 labeled) oligonucl ...199910049902
changes in the evolution of the antigenic profiles and morphology during coccoid conversion of helicobacter pylori.the significance of the coccoid forms of h. pylori is still controversial and the questions of whether these forms are viable and infective or degenerative are still open. we induced conversion from rod to coccoid forms and studied morphological changes and antigenic evolutions during this conversion and, thereby, elucidated the viability of coccoid forms.199910063308
apoptotic effect of outer-membrane proteins from campylobacter jejuni on chicken lymphocytes.campylobacter jejuni is a significant cause of food-borne diseases in humans. the bacterium is considered a commensal organism in chickens, and it can heavily colonize chickens without causing inflammation. poultry may be the major reservoir for the human infection in developed countries. here we show that an outer-membrane protein extract prepared from the bacteria caused apoptosis of chicken lymphocytes detected in vitro with the terminal deoxynucleotidyl transferase-mediated dutp nick end-lab ...199910069862
evaluation of accuracy and repeatability of identification of food-borne pathogens by automated bacterial identification systems.the performances of five automated microbial identification systems, relative to that of a reference identification system, for their ability to accurately and repeatedly identify six common food-borne pathogens were assessed. the systems assessed were the microlog system (biolog inc., hayward, calif.), the microbial identification system (mis; midi inc., newark, del.), the vitek system (biomérieux vitek, hazelwood, mo.), the microscan walkaway 40 system (dade-microscan international, west sacra ...199910074506
identification and characterization of is2404 and is2606: two distinct repeated sequences for detection of mycobacterium ulcerans by pcr.molecular analysis of mycobacterium ulcerans has revealed two new insertion sequences (iss), is2404 and is2606. is2404 was identified by complete sequencing of a previously described repetitive dna segment from m. ulcerans. this element is 1,274 bp long, contains 12-bp inverted repeats and a single open reading frame (orf) potentially encoding a protein of 327 amino acids (aa), and apparently generates 7-bp direct repeats upon transposition. amino acid similarity was found between the putative t ...199910074520
cloning, mutation and distribution of a putative lipopolysaccharide biosynthesis locus in campylobacter jejuni.a region encoding orfs with homology to known lipopolysaccharide (lps) biosynthesis genes was isolated from two strains of campylobacter jejuni. one of the strains produces lps, but the second strain is reported to produce only lipooligosaccharide (los) and therefore lacks the o-chain. the two strains shared six predicted orfs, but an additional orf, orfe, of unknown function was identified in the los-producing strain. mutation of the shared wbee (rfbe) homologue (orff) or deletion of five of th ...199910075420
[campylobacter fetus bacteremia and thrombophlebitis in a patient with waldenstrom's macroglobulinemia].we report a 67-year-old male with waldenstrom's macroglobulinemia who developed campylobacter fetus subspesis fetus (c. fetus) bacteremia and thrombophlebitis. the patient developed a fever and pain in his left lower limb, and could not walk because of the pain. radioisotopic venography showed thrombophlebitis in his left lower limb. his blood culture grew c. fetus. after starting intravenous papm/bp, his symptoms resolved promptly. in contrast to campylobacter jejuni which is a common cause of ...199910077907
campylobacter jejuni--an emerging foodborne pathogen.campylobacter jejuni is the most commonly reported bacterial cause of foodborne infection in the united states. adding to the human and economic costs are chronic sequelae associated with c. jejuni infection--guillian-barré syndrome and reactive arthritis. in addition, an increasing proportion of human infections caused by c. jejuni are resistant to antimicrobial therapy. mishandling of raw poultry and consumption of undercooked poultry are the major risk factors for human campylobacteriosis. ef ...199910081669
[lumbar puncture in a pediatric emergency department: something more than a diagnostic technic].the aim of this study was to know the incidence of serious bacterial infections (sbi) in children without sepsis or intracranial infection in which spinal puncture (lp) was performed in an emergency department.199910083638
expression, purification, crystallization and preliminary x-ray diffraction results from campylobacter jejuni ferritin.the prokaryotic ferritin gene of campylobacter jejuni was overexpressed in escherichia coli under control of the bacteriophage t7 promoter and the protein (cj-ftn) purified. preliminary crystallization experiments have been performed using the hanging-drop vapour-diffusion method with ammonium sulfate as the precipitant. diffraction studies show the crystals belong to the i432 space group (a = 151.52 a). structure solution by molecular replacement is in progress while crystal quality improvement ...199910089431
spectrum and antimicrobial activity of alexomycin (pnu-82, 127), a peptide compound projected for use in animal health.alexomycin (pnu-82, 127) is a thiopeptide antimicrobial complex intended for veterinary practice that belongs to a series of cyclic peptides produced by streptomyces arginensis. mics against selected routine and fastidious clinical isolates of animal and human origin were determined by broth microdilution or agar dilution reference methods. alexomycin was active against gram-positive pathogens such as oxacillin-susceptible and -resistant staphylococcus aureus and coagulase-negative staphylococci ...199910092967
the bspa locus of lactobacillus fermentum br11 encodes an l-cystine uptake system.bspa is a basic surface-exposed protein from lactobacillus fermentum br11. sequence comparisons have shown that it is a member of family iii of the solute binding proteins. it is 89% identical to the collagen binding protein, cnb, from lactobacillus reuteri. compared with the database of escherichia coli proteins, bspa is most similar to the l-cystine binding protein fliy. to investigate the function of bspa, mutants depleted for bspa were generated by homologous recombination with a temperature ...199910094698
mutational analysis of the vaca promoter provides insight into gene transcription in helicobacter pylori.analysis of 12 helicobacter pylori promoters indicates the existence of a consensus -10 hexamer (tataat) but little conservation of -35 sequences. in this study, mutations in either the h. pylori vaca -10 region or the -35 region resulted in decreased vaca transcription and suggested that an extended -10 motif is utilized. thus, despite the lack of a -35 consensus sequence for h. pylori promoters, the -35 region plays a functional role in vaca transcription.199910094707
the risk of guillain-barré syndrome following infection with campylobacter jejuni.to estimate the incidence of guillain-barré syndrome (gbs) following campylobacter jejuni infection (ci) we studied three populations where outbreaks of ci had occurred involving an estimated 8000 cases. no case of gbs was detected in the 6 months following the outbreaks in the local populations. the point estimate for the risk of gbs following ci estimated in this study was 0 in 8000 (95% confidence interval 0-3).199910098780
enteropathogenic bacteria in faecal swabs of young children fed on lactic acid-fermented cereal gruels.the influence of consumption of a lactic acid-fermented cereal gruel togwa with ph < or = 4 on the presence of faecal enteric bacteria such as campylobacter, enterohaemorrhagic escherichia coli (ehec:o157), enterotoxigenic escherichia coli (etec), salmonella and shigella was evaluated. under 5 years old healthy children listed in an ascending order of age were alternatively assigned and given either a lactic-acid fermented cereal gruel togwa (test diet) or an unfermented cereal gruel uji (contro ...199910098782
serotypes and typability of campylobacter jejuni and campylobacter coli isolated from poultry products.campylobacter infection is one of the most common bacterial enteric pathogens. campylobacter jejuni and campylobacter coli infections are mostly food- and waterborne and especially poultry is often assumed to be an important source. the heat-stable serotyping system (the 'penner' scheme) was used to study the serotype distribution of c. jejuni and c. coli isolated from different food products of poultry origin sampled from retail outlets in denmark. a total of 156 isolates were serotyped, 85% of ...199910100900
detection of cytolethal distending toxin activity and cdt genes in campylobacter spp. isolated from chicken carcasses.this study was designed to determine whether isolates from chicken carcasses, the primary source of campylobacter jejuni and campylobacter coli in human infections, commonly carry the cdt genes and also whether active cytolethal distending toxin (cdt) is produced by these isolates. campylobacter spp. were isolated from all 91 fresh chicken carcasses purchased from local supermarkets. campylobacter spp. were identified on the basis of both biochemical and pcr tests. of the 105 isolates, 70 (67%) ...199910103243
detection of small numbers of campylobacter jejuni and campylobacter coli cells in environmental water, sewage, and food samples by a seminested pcr assay.a rapid and sensitive assay was developed for detection of small numbers of campylobacter jejuni and campylobacter coli cells in environmental water, sewage, and food samples. water and sewage samples were filtered, and the filters were enriched overnight in a nonselective medium. the enrichment cultures were prepared for pcr by a rapid and simple procedure consisting of centrifugation, proteinase k treatment, and boiling. a seminested pcr based on specific amplification of the intergenic sequen ...199910103261
ganglioside gm1 mimicry in campylobacter strains from sporadic infections in the united states.to determine whether gm1-like epitopes in campylobacter species are specific to o serotypes associated with guillain-barré syndrome (gbs) or whether they are frequent among random campylobacter isolates causing enteritis, 275 random enteritis-associated isolates of campylobacter jejuni were analyzed. to determine whether gm1-like epitopes in campylobacter species are specific to o serotypes associated with guillan-barre syndrome (gbs) or whether they are frequent among random campylobacter isola ...199910191221
the clpb protein from campylobacter jejuni: molecular characterization of the encoding gene and antigenicity of the recombinant protein.the clpb heat-shock protein is necessary for the survival of escherichia coli cells upon sudden increase of temperature. using a pcr-based genomic walking method, the nucleotide sequence of a clpb homolog from campylobacter jejuni was determined. the clpb gene encodes a protein of 857 amino acid (aa) residues, with a predicted molecular mass of 95.3kda. alignment of the deduced aa sequence with other known bacterial clpb proteins revealed overall identity from 47% (e. coli) to 61% (helicobacter ...199910196475
serotyping of campylobacter jejuni based on heat-stable antigens: relevance, molecular basis and implications in pathogenesis. 199910196742
intermittent shedding of thermophilic campylobacters by sheep at pasture.the rates at which sheep on different types of pasture shed campylobacters in their faeces were measured over 12 months. overall, shedding of campylobacters at pasture was between a third and a half of the carriage rate (92%) of the intestines of sheep at slaughter. shedding was highest during saltmarsh grazing, followed by upland fell and farm grazing. the rate of shedding varied at different times of the year, with the highest rates (100%) coinciding with lambing, weaning, and movement onto ne ...199910196758
morphological changes of synchronized campylobacter jejuni populations during growth in single phase liquid culture.campylobacter jejuni strains demonstrate a variety of growth phase-linked distinct morphological forms when grown in liquid culture. the typical spiral form of the organism, evident during logarithmic phase, undergoes elongation during stationary phase before becoming coccoid via the formation of membrane blebs and budded forms in decline phase. cellular elongation and coccoid formation occurred despite the inhibition of protein synthesis and without a detectable change in the protein components ...199910196767
identification of a gene encoding an immuno-reactive membrane protein from campylobacter jejuni.a gene encoding a putative membrane protein has been identified from campylobacter jejuni nctc 11168 following an immuno-screen of a lambda zap ii genomic dna library with antiserum raised against glycine-extractable proteins. the nucleotide sequence of the entire genomic insert revealed six open reading frames, all but one of which have sequence homologues in the complete genome sequence of helicobacter pylori. the gene encoding the immuno-reactive protein was further identified by independent ...199910196775
isolation of helicobacter pylori genes that modulate urease activity.helicobacter pylori urease, a nickel-requiring metalloenzyme, hydrolyzes urea to nh3 and co2. we sought to identify h. pylori genes that modulate urease activity by constructing php8080, a plasmid which encodes both h. pylori urease and the nixa nickel transporter. escherichia coli se5000 and dh5alpha transformed with php8080 resulted in a high-level urease producer and a low-level urease producer, respectively. an h. pylori dna library was cotransformed into se5000 (php8080) and dh5alpha (php80 ...199910198012
campylobacter jejuni ii peritonitis in a ccpd patient: cure by oral clarithromycin. 199910201350
actinobacillus actinomycetemcomitans immunosuppressive protein is a member of the family of cytolethal distending toxins capable of causing a g2 arrest in human t cells.we have previously shown that actinobacillus actinomycetecomitans produces an immunosuppressive factor (isf) capable of impairing human lymphocyte function by perturbing cell cycle progression. we now report that isf is the product of the cdtb gene, one of three genes encoding the family of cytolethal distending toxins (cdt). the isf polypeptide exhibits >/=95% identity with hemophilus ducreyi cdtb protein and </=60% homology with escherichia coli or campylobacter jejuni cdtb. pretreatment of ph ...199910202019
predictive fluorescent amplified-fragment length polymorphism analysis of escherichia coli: high-resolution typing method with phylogenetic significance.the fluorescent amplified-fragment length polymorphism (faflp) assay potentially amplifies a unique set of genome fragments from each bacterial clone. it uses stringently hybridizing primers which carry a fluorescent label. precise fragment sizing is achieved by the inclusion of an internal size standard in every lane. therefore, a unique genotype identifier(s) can be found in the form of fragments of precise size or sizes, and these can be generated reproducibly. in order to evaluate the potent ...199910203470
serological discrimination of dogs infected with gastric helicobacter spp. and uninfected dogs.characterization of the humoral immune responses of people to helicobacter pylori infection has facilitated the investigation of the host response to bacterial virulence factors and the development of sensitive and specific diagnostic tests. dogs are commonly infected with gastric helicobacter spp., but the presence of multiple helicobacter spp. and possible coinfection in individual dogs have complicated serological evaluation. evaluation of the antigenic homology of helicobacter spp. revealed ...199910203471
cytolethal distending toxin genes in campylobacter jejuni and campylobacter coli isolates: detection and analysis by pcr.campylobacter jejuni produces a toxin called cytolethal distending toxin (cdt). knowledge of the prevalence and homogeneity of campylobacter sp. cdt genes is incomplete. in this work, we identified four pcr primer pairs that collectively amplified cdt genes in all of the c. jejuni and campylobacter coli strains tested. restriction analyses of the cdt pcr products showed clear differences between the cdt genes of these two species, yet there were few heterogeneities noted between members of the s ...199910203548
cloning, sequencing and molecular analysis of the campylobacter jejuni groesl bicistronic operon.the groesl bicistronic operon from the enteric pathogen campylobacter jejuni was cloned and sequenced. it consists of two orfs encoding proteins with molecular masses of 9.5 and 57.9 kda, which showed a high degree of homology to other bacterial groes and groel proteins. northern blot analysis suggested that the groesl operon is transcribed as a bicistronic mrna, and its steady-state level was markedly increased after temperature upshift. by primer extension assay, one potential transcription st ...199910206714
differentiation of campylobacter coli and c. jejuni by length and dna sequence of the 16s-23s rrna internal spacer region.the internal spacer region (isr) between the 16s and 23s rrna genes of campylobacter was investigated by pcr fragment length typing and dna sequencing of clinical and chicken wild-type isolates. pcr fragment length typing showed one fragment of 859 nt in length for the 12 strains of campylobacter coli investigated. thirty-six of the campylobacter jejuni subsp. jejuni strains possessed one fragment, which varied in size between 727 and 802 nt. three strains showed two fragments between 501 and 92 ...199910206715
the use of hipo, encoding benzoylglycine amidohydrolase (hippuricase), as a reporter of gene expression in campylobacter coli.a novel integrative promoter probe vector which utilizes the campylobacter jejuni hipo gene as a reporter of gene expression was developed as a genetic tool in campylobacter coli. the utility of the system was demonstrated by coupling expression of the hipo reporter to the promoters of flaa, flab and kata. subsequently, expression of these genes could be monitored accurately from chromosomally-borne transcriptional fusions using a simple non-destructive colorimetric assay. the system should serv ...199910212441
the yersinia enterocolitica motility master regulatory operon, flhdc, is required for flagellin production, swimming motility, and swarming motility.the ability to move over and colonize surface substrata has been linked to the formation of biofilms and to the virulence of some bacterial pathogens. results from this study show that the gastrointestinal pathogen yersinia enterocolitica can migrate over and colonize surfaces by swarming motility, a form of cooperative multicellular behavior. immunoblot analysis and electron microscopy indicated that swarming motility is dependent on the same flagellum organelle that is required for swimming mo ...199910217774
high-resolution genomic fingerprinting of campylobacter jejuni and campylobacter coli by analysis of amplified fragment length polymorphisms.a method for high-resolution genomic fingerprinting of the enteric pathogens campylobacter jejuni and campylobacter coli, based on the determination of amplified fragment length polymorphism, is described. the potential of this method for molecular epidemiological studies of these species is evaluated with 50 type, reference, and well-characterised field strains. amplified fragment length polymorphism fingerprints comprised over 60 bands detected in the size range 35-500 bp. groups of outbreak s ...199910220884
sequence analysis of the gyra and parc homologues of a wild-type strain of vibrio parahaemolyticus and its fluoroquinolone-resistant mutants.vibrio parahaemolyticus causes seafood-borne gastroenteritis in humans. it is particularly important in japan, where raw seafood is frequently consumed. fluoroquinolone is one of the current drugs of choice for treating patients infected by v. parahaemolyticus because resistant strains are rarely found. to study a possible fluoroquinolone resistance mechanism in this organism, nucleotide sequences that are homologous to known gyra and parc genes have been cloned from v. parahaemolyticus aq3815 a ...199910223929
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