TitleAbstractYear(sorted ascending)
identification of the vibrio cholerae enterobactin receptors vcta and irga: irga is not required for virulence.the gram-negative enteric pathogen vibrio cholerae requires iron for growth. v. cholerae has multiple iron acquisition systems, including utilization of heme and hemoglobin, synthesis and transport of the catechol siderophore vibriobactin, and transport of several siderophores that it does not itself make. one siderophore that v. cholerae transports, but does not make, is enterobactin. enterobactin transport requires tonb and is independent of the vibriobactin receptor viua. in this study, two c ...200212065481
cmeabc functions as a multidrug efflux system in campylobacter jejuni.campylobacter jejuni, a gram-negative organism causing gastroenteritis in humans, is increasingly resistant to antibiotics. however, little is known about the drug efflux mechanisms in this pathogen. here we characterized an efflux pump encoded by a three-gene operon (designated cmeabc) that contributes to multidrug resistance in c. jejuni 81-176. cmeabc shares significant sequence and structural homology with known tripartite multidrug efflux pumps in other gram-negative bacteria, and it consis ...200212069964
campylobacter coli pulsed field gel electrophoresis genotypic diversity among sows and piglets in a farrowing barn.genotypes of campylobacter coli isolates from feces of three sows and rectal swabs of 17 piglets were examined by pulsed field gel electrophoresis (pfge). all of the animals originated from a single farrowing barn of a farrow-to-finish swine operation. five campylobacter colonies were picked from a single agar plate for each sample after broth enrichment and growth on campy-cefex agar. genotypes were examined by pfge after genomic dna digestion with smai and sacii restriction endonucleases. twen ...200212070692
growth of campylobacter jejuni supported by respiration of fumarate, nitrate, nitrite, trimethylamine-n-oxide, or dimethyl sulfoxide requires oxygen.the human gastrointestinal pathogen campylobacter jejuni is a microaerophilic bacterium with a respiratory metabolism. the genome sequence of c. jejuni strain 11168 reveals the presence of genes that encode terminal reductases that are predicted to allow the use of a wide range of alternative electron acceptors to oxygen, including fumarate, nitrate, nitrite, and n- or s-oxides. all of these reductase activities were present in cells of strain 11168, and the molybdoenzyme encoded by cj0264c was ...200212107136
characterization of pit, a streptococcus pneumoniae iron uptake abc transporter.bacteria frequently have multiple mechanisms for acquiring iron, an essential micronutrient, from the environment. we have identified a four-gene streptococcus pneumoniae operon, named pit, encoding proteins with similarity to components of a putative brachyspira hyodysenteriae iron uptake abc transporter, bit. an s. pneumoniae strain containing a defined mutation in pit has impaired growth in medium containing the iron chelator ethylenediamine di-o-hydroxyphenylacetic acid, reduced sensitivity ...200212117949
genome-wide transcriptional profiling in a histidine kinase mutant of helicobacter pylori identifies members of a identify putative members of a regulon controlled by the h. pylori sensory histidine kinase hp0164 (hk0164), we constructed hk0164 null mutant h. pylori strains and analyzed bacterial gene transcription using dna arrays. seven genes were differentially expressed in multiple hk0164 mutant strains compared to their expression in control strains. strain-dependent variations in differential expression were also detected. these results indicate that the signal transduction circuit utilizing hk0164 ...200212142435
genetic basis of quinolone resistance and epidemiology of resistant and susceptible isolates of porcine campylobacter coli strains.the aims of this study were to investigate the epidemiology of quinolone-resistant and -susceptible porcine isolates of campylobacter coli and to characterize the genetic basis of quinolone resistance.200212147072
effects of repeated subculturing and prolonged storage at room temperature of enterohemorrhagic escherichia coli o157:h7 on pulsed-field gel electrophoresis profiles.three clinical strains of enterohemorrhagic escherichia coli o157:h7 which were subcultured repeatedly or stored at room temperature over a 25-week period showed appreciable variations in their pulsed-field gel electrophoresis fragment patterns. the variations could be explained by a couple of spontaneous genetic events at most and thus did not invalidate the genetic lineage of the strains.200212149386
prevalence of thermophilic campylobacter spp. in ready-to-eat foods and raw poultry in northern ireland.although there have been numerous studies investigating the prevalence of campylobacters in animals and raw meats, there are limited data on the persistence of these organisms in ready-to-eat (rte) foodstuffs. although poultry is now well established as a major reservoir of thermophilic campylobacters, it is widely assumed that hazard analysis critical control point (haccp) controls in commercial and industrial settings are effective in eliminating this hazard through thorough cooking of rte pro ...200212182488
a case-case comparison of campylobacter coli and campylobacter jejuni infection: a tool for generating hypotheses.preventing campylobacteriosis depends on a thorough understanding of its epidemiology. we used case-case analysis to compare cases of campylobacter coli infection with cases of c. jejuni infection, to generate hypotheses for infection from standardized, population-based sentinel surveillance information in england and wales. persons with c. coli infection were more likely to have drunk bottled water than were those with c. jejuni infection and, in general, were more likely to have eaten pâté. im ...200212194770
quorum sensing and production of autoinducer-2 in campylobacter spp., escherichia coli o157:h7, and salmonella enterica serovar typhimurium in foods.autoinducer molecules are utilized by gram-negative and gram-positive bacteria to regulate density-dependent gene expression by a mechanism known as quorum sensing. pcr and dna sequencing results showed that campylobacter jejuni and campylobacter coli possessed luxs, which is responsible for autoinducer-2 (ai-2) production. using a vibrio harveyi luminescence assay, the production of ai-2 was observed in milk, chicken broth, and brucella broth by c. coli, c. jejuni, salmonella enterica serovar t ...200212200329
distribution of environmentally regulated genes of streptococcus suis serotype 2 among s. suis serotypes and other organisms.the occurrence of 36 environmentally regulated genes of streptococcus suis strain 10 among all 35 s. suis serotypes was determined by using hybridization with the amplified genes as probes. in addition, the distribution of these genes among the virulence phenotypes of serotypes 1 and 2 was assessed. hybridization was also performed with various other streptococcal species and nonstreptococcal bacterial species which may be present in pigs. interestingly, probe ivs-25/iri-1, similar to agra and s ...200212202563
use of a lightcycler gyra mutation assay for identification of ciprofloxacin-resistant campylobacter coli.a fluorescence resonance energy transfer-based assay has been employed to detect mutations at the 86 codon in the dna gyrase a (gyra) gene in campylobacter coli strains. these mutations were associated with ciprofloxacin resistance in strains isolated in italy in 2000. the mutations in the gyra gene were detected by real-time pcr amplification followed by hybridization with two fluorescent probes designed with sequences complementary to the wild-type c. coli gyra gene. mutation detection was per ...200212204377
identification and localization of flagellins flaa and flab3 within flagella of methanococcus voltae.methanococcus voltae possesses four flagellin genes, two of which (flab1 and flab2) have previously been reported to encode major components of the flagellar filament. the remaining two flagellin genes, flaa and flab3, are transcribed at lower levels, and the corresponding proteins remained undetected prior to this work. electron microscopy examination of flagella isolated by detergent extraction of whole cells revealed a curved, hook-like region of varying length at the end of a long filament. ...200212218007
campylobacter coli bacteremia in an 11-year-old boy. 200212225560
two predicted chemoreceptors of helicobacter pylori promote stomach infection.helicobacter pylori must be motile or display chemotaxis to be able to fully infect mammals, but it is not known how this chemotaxis is directed. we disrupted two genes encoding predicted chemoreceptors, tlpa and tlpc. h. pylori mutants lacking either of these genes are fully motile and chemotactic in vitro and are as able as the wild type to infect mice when they are the sole infecting strains. in contrast, when mice are coinfected with the h. pylori ss1 tlpa or tlpc mutant and the wild type, w ...200212228322
long-term antibody responses following human infection with campylobacter jejuni.epidemiological evidence suggests prior infection of humans by campylobacter jejuni leads to protection against disease following further exposure. it is known that infections elicit strong antibody responses following the onset of disease and that antibody levels are elevated in putatively immune populations. to determine if systemic and mucosal antibodies induced by a confirmed infection remain at elevated levels for prolonged periods, repeat serum, saliva and urine samples were taken from cam ...200212296859
polyphosphate kinase from activated sludge performing enhanced biological phosphorus removal.a novel polyphosphate kinase (ppk) was retrieved from an uncultivated organism in activated sludge carrying out enhanced biological phosphorus removal (ebpr). acetate-fed laboratory-scale sequencing batch reactors were used to maintain sludge with a high phosphorus content (approximately 11% of the biomass). pcr-based clone libraries of small subunit rrna genes and fluorescent in situ hybridization (fish) were used to verify that the sludge was enriched in rhodocyclus-like beta-proteobacteria kn ...200212324346
double-staining method for differentiation of morphological changes and membrane integrity of campylobacter coli cells.we developed a double-staining procedure involving nanoorange dye (molecular probes, eugene, oreg.) and membrane integrity stains (live/dead baclight kit; molecular probes) to show the morphological and membrane integrity changes of campylobacter coli cells during growth. the conversion from a spiral to a coccoid morphology via intermediary forms and the membrane integrity changes of the c. coli cells can be detected with the double-staining procedure. our data indicate that young or actively gr ...200212324366
detection of helicobacter colonization of the murine lower bowel by genus-specific pcr-denaturing gradient gel electrophoresis.helicobacter genus-specific pcr and denaturing gradient gel electrophoresis can detect and speciate the helicobacters that colonize the lower bowel of laboratory mice. the method's sensitivity is comparable to that of species-specific pcr and may detect unnamed helicobacter species. this approach should prove useful for commercial and research murine facilities.200212324369
trends in antimicrobial susceptibility among isolates of campylobacter species in ireland and the emergence of resistance to ciprofloxacin.measurements were made of the susceptibility to six commonly prescribed antibiotics, including erythromycin, tetracycline and ciprofloxacin, of 130 isolates of campylobacterjejuni and 15 isolates of campylobacter coli cultured from human and poultry sources during 2000. the results were compared with the results from a collection of strains isolated between 1996 and 1998. the levels of resistance to erythromycin remained low, 2 per cent and 4.4 per cent for the human and poultry isolates, respec ...200212356234
comparison of the etest and agar dilution for in vitro antimicrobial susceptibility testing of campylobacter.the performance of the etest and agar dilution for in vitro antimicrobial susceptibility of campylobacter spp. was evaluated using a quality control strain campylobactor jejuni atcc 33560, and 81 c. jejuni and 54 campylobacter coli isolates recovered from retail raw meats. seven antimicrobial agents: chloramphenicol, ciprofloxacin, doxycycline, erythromycin, gentamicin, nalidixic acid and tetracycline, were tested using the two methods, whereas azithromycin was tested using the etest only. the c ...200212356792
evaluation of a commercial diagnostic pcr for the identification of campylobacter jejuni and campylobacter coli.aims: dupont qualicon recently developed a new pcr assay for the identification of campylobacter jejuni and campylobacter coli. we evaluated the selectivity and utility of this assay compared with a pcr method already in use in our laboratory. methods and results: a group of 133 campylobacter isolates from poultry carcass rinse samples were screened using the commercial pcr and standard pcr. identical results were found for 89.5% (119/133) of the isolates. however, 10.5% (14/133) gave conflictin ...200212358702
genetic diversity and relationships of campylobacter species and subspecies.the existence of tremendous genetic diversity within campylobacter species has been well documented. to analyse the population structure of campylobacter and determine whether or not a clonal population structure could be detected, genetic diversity was assessed within the genus campylobacter by multilocus enzyme electrophoresis of 156 isolates representing 11 species and subspecies from disparate sources. analyses of electrophoretic mobility of 11 enzymes revealed 109 electrophoretic types (ets ...200212361288
characterization of the gene encoding the major secreted lysophospholipase a of legionella pneumophila and its role in detoxification of lysophosphatidylcholine.we previously showed that legionella pneumophila secretes, via its type ii secretion system, phospholipase a activities that are distinguished by their specificity for certain phospholipids. in this study, we identified and characterized plaa, a gene encoding a phospholipase a that cleaves fatty acids from lysophospholipids. the plaa gene encoded a 309-amino-acid protein (plaa) which had homology to a group of lipolytic enzymes containing the catalytic signature gdsl. in escherichia coli, the cl ...200212379686
dna sequence and mutational analyses of the pvir plasmid of campylobacter jejuni 81-176.the circular pvir plasmid of campylobacter jejuni strain 81-176 was determined to be 37,468 nucleotides in length with a g+c content of 26%. a total of 83% of the plasmid represented coding information, and all but 2 of the 54 predicted open reading frames were encoded on the same dna strand. there were seven genes on the plasmid in a continguous region of 8.9 kb that encoded orthologs of type iv secretion proteins found in helicobacter pylori, including four that have been described previously ...200212379703
impediometric detection of campylobacter coli.the rapid automated bacterial impedance technique (rabit) was examined as a method for the detection of two wild-type isolates of campylobacter coli in broth media. both isolates failed to produce a change in impedance that was sufficient for detection in any combination of six nonselective basal broth media, including mueller-hinton broth, nutrient broth no. 2, brain heart infusion broth supplemented with yeast extract (0.5% [wt/vol]), brucella broth, campy broth supplemented with yeast extract ...200212380757
speciation of thermotolerant campylobacter isolates involved in foodborne disease by means of dna restriction analysis and molecular probes.the molecular identification of several strains of campylobacter jejuni and campylobacter coli involved in foodborne disease was carried out by investigating the restriction profiles of their chromosomal dna and by dna/dna hybridization. cleavage with ecorv allowed the visualization of a 3 kb dna fragment characteristic of c. jejuni, whereas restriction with clai allowed the identification of a 9.3 kb dna fragment, also characteristic of c. jejuni, and a dna duplet of 9.5-10 kb, specific to c. c ...200212381150
structural heterogeneity of carbohydrate modifications affects serospecificity of campylobacter flagellins.flagellin from campylobacter coli vc167 is post-translationally modified at > or = 16 amino acid residues with pseudaminic acid and three related derivatives. the predominant modification was 5,7-diacetamido-3,5,7,9 - tetradeoxy - l - glycero - l - manno - nonulosonic acid (pseudaminic acid, pse5ac7ac), a modification that has been described previously on flagellin from campylobacter jejuni 81-176. vc167 lacked two modi-fications present in 81-176 and instead had two unique modifications of mass ...200212406231
requirement of flha for swarming differentiation, flagellin export, and secretion of virulence-associated proteins in bacillus thuringiensis.bacillus thuringiensis is being used worldwide as a biopesticide, although increasing evidence suggests that it is emerging as an opportunistic human pathogen. while phospholipases, hemolysins, and enterotoxins are claimed to be responsible for b. thuringiensis virulence, there is no direct evidence to indicate that the flagellum-driven motility plays a role in parasite-host interactions. this report describes the characterization of a mini-tn10 mutant of b. thuringiensis that is defective in fl ...200212426328
speciating campylobacter jejuni and campylobacter coli isolates from poultry and humans using six pcr-based assays.six previously published polymerase chain reaction (pcr) assays each targeting different genes were used to speciate 116 isolates previously identified as campylobacter jejuni using routine microbiological techniques. of the 116 isolates, 84 were of poultry origin and 32 of human origin. the six pcr assays confirmed the species identities of 31 of 32 (97%) human isolates and 56 of 84 (67%) poultry isolates as c. jejuni. twenty eight of 84 (33%) poultry isolates were identified as campylobacter c ...200212435503
molecular diversity of campylobacter coli and c. jejuni isolated from pigs at slaughter by flaa-rflp analysis and ribotyping.a population of porcine isolates of camplobacter jejuni (n = 11) and c. coli (n = 17) were examined for genotypic relatedness employing ribotyping, as well as polymerase chain reaction-restriction fragment length polymorphism (pcr-rflp) analysis of the flagellin (fla)a gene locus. pcr was employed to amplify a 533 bp fragment from the flaa gene, including the previously described short variable region (svr), employing the novel primers, a2 and al and successfully generated this amplicon for all ...200212449248
prevalence of campylobacter jejuni, campylobacter lari, and campylobacter coli in different ecological guilds and taxa of migrating birds.a total of 1,794 migrating birds trapped at a coastal site in southern sweden were sampled for detection of campylobacter spp. all isolates phenotypically identified as campylobacter jejuni and a subset of those identified as non-c. jejuni were identified to the species level by pcr-based techniques. c. jejuni was found in 5.0% of the birds, campylobacter lari was found in 5.6%, and campylobacter coli was found in 0.9%. an additional 10.7% of the tested birds were infected with hippurate hydroly ...200212450810
campylobacter jejuni in black-headed gulls (larus ridibundus): prevalence, genotypes, and influence on c. jejuni epidemiology.campylobacteriosis is a zoonotic disease in which birds have been suggested to play an important role as a reservoir. we investigated the prevalence of campylobacter jejuni subsp. jejuni in black-headed gulls (larus ridibundus) in southern sweden with the aim of examining the nature of c. jejuni infection in this bird species. birds were sampled in four sampling series each year during 1999 (n = 419) and 2000 (n = 365). longitudinally sampled c. jejuni isolates from individual gulls were subject ...200212454158
rapid pcr using nested primers of the 16s rrna and the hippuricase (hip o) genes to detect campylobacter jejuni and campylobacter coli in environmental samples.identification of sources campylobacter infection in the poultry houses is in general problematic due to the lack of reliable methods to detect campylobacteria in environmental samples. detection of campylobacteria in environmental samples by conventional culture methods is difficult and of limited sensitivity due to the use of selective media, the low number of bacteria in the samples and possibly also due to the presence of non-culturable or sub-lethally injured stages of the bacteria. the pre ...200212477440
a polyphosphate kinase (ppk2) widely conserved in bacteria.synthesis of inorganic polyphosphate (poly p) from the terminal phosphate of atp is catalyzed reversibly by poly p kinase (ppk, now designated ppk1) initially isolated from escherichia coli. ppk1 is highly conserved in many bacteria, including some of the major pathogens such as pseudomonas aeruginosa. in a null mutant of p. aeruginosa lacking ppk1, we have discovered a previously uncharacterized ppk activity (designated ppk2) distinguished from ppk1 by the following: synthesis of poly p from gt ...200212486232
role of campylobacter jejuni/coli in diarrhoea in ile-ife, nigeria.campylobacter jejuni/coli are well established causative agents of diarrhoea. in nigeria, gastroenteritis due to c. jejuni was first reported in northern part of the country in 1981 and the south-western part in ile-ife in 1983.200212638844
evaluation of a novel heminested pcr assay based on the phosphoglucosamine mutase gene for detection of helicobacter pylori in saliva and dental plaque.a novel heminested pcr protocol was developed for the specific detection of helicobacter pylori at low copy numbers. a set of primers specific for the phosphoglucosamine mutase gene (glmm) of h. pylori produced a 765-bp fragment that was used as template for the heminested primer pair delineating a 496-bp fragment. by using agarose gel electrophoresis for detection of the heminested pcr-amplified products, amplification of h. pylori genomic dna was achieved at concentrations as low as 0.1 pg, eq ...200211773117
the non-h pylori helicobacters: their expanding role in gastrointestinal and systemic diseases.the number of species in the genus helicobacter has rapidly expanded over the past decade. the genus now includes at least 24 formally named species as well as numerous other helicobacters awaiting formal naming. this review highlights the expanding role that other helicobacters, although not as well known as h pylori, play in gastrointestinal and systemic disease in humans.200211788573
the helicobacter pylori homologue of the ferric uptake regulator is involved in acid resistance.the only known niche of the human pathogen helicobacter pylori is the gastric mucosa, where large fluctuations of ph occur, indicating that the bacterial response and resistance to acid are important for successful colonization. one of the few regulatory proteins in the h. pylori genome is a homologue of the ferric uptake regulator (fur). in most bacteria, the main function of fur is the regulation of iron homeostasis. however, in salmonella enterica serovar typhimurium, fur also plays an import ...200211796589
use of a multiplex pcr-based assay to differentiate campylobacter jejuni and campylobacter coli strains isolated from human and animal sources. 200211749144
identification of target genes regulated by the two-component system hp166-hp165 of helicobacter pylori.two-component systems are signal transduction systems which enable bacteria to regulate cellular functions in response to changing environmental conditions. in most cases regulation is accomplished on the transcriptional level by a response regulator protein, which, according to the phosphorylation state of its receiver domain, displays different affinities for its target promoters. here we describe identification of genes regulated by the two-component system hp166-hp165 of helicobacter pylori ...200211751811
[campylobacter jejuni and c. coli in aborted swine: comparison between phenotypic identification and polyacrylamide gel protein profiles].campylobacter jejuni and campylobacter coli were isolated from aborted pig fetuses which proceeded from different animals and farms between february 2000 and march 2001. seven campylobacter jejuni biotype ii, three biotype i and one campylobacter coli biotype i were identified by phenotypic tests and lior's scheme. to corroborate and compare the phenotypic results, 7.5, 10 and 12.5% polyacrilamide gel electrophoresis (sds-page) were used under reducing conditions. characteristic bands of hyperva ...200212600003
impact of transport crate reuse and of catching and processing on campylobacter and salmonella contamination of broiler chickens.the influence of transport, catching, and processing on contamination of broiler chickens with salmonella and campylobacter was investigated. transport crates were reused with high frequency and were often still contaminated with salmonella and campylobacter when they arrived at the farm despite the fact that they were washed at the factory, and thus they were a potential route of infection. these organisms contaminated the feathers of previously campylobacter- and salmonella-negative birds goin ...200211823211
lectin typing of campylobacter concisus.a total of 44 clinical isolates and the type strain of the putative pathogen campylobacter concisus were grouped based on their reactions with plant lectins. the optimized lectin typing system used c. concisus strains proteolytically pretreated and subsequently typed by using a panel of four lectins. the system grouped all 45 strains into 13 lectin reaction patterns, leaving no strain untypeable due to autoagglutination. lectin types were both stable and reproducible.200211826005
a multiplex polymerase chain reaction for the differentiation of campylobacter jejuni and campylobacter coli from a swine processing facility and characterization of isolates by pulsed-field gel electrophoresis and antibiotic resistance profiles.a multiplex polymerase chain reaction (pcr) was developed for the detection and speciation of 60 campylobacter strains isolated from porcine rectal swabs and from different areas in a pork processing plant. the pcr assay was based on primers specific for the cadf gene of pathogenic campylobacter species, a specific but undefined gene of campylobacter jejuni, and the ceue gene of campylobacter coli. further characterization of these isolates was established by pulsed-field gel electrophoresis (pf ...200211848556
antimicrobial resistance and plasmid profiles of campylobacter jejuni and campylobacter coli from human and animal sources.the purpose of this study was to determine the susceptibility of campylobacter jejuni and campylobacter coli isolates to antimicrobial agents and to investigate the presence of plasmid dna.200211849513
subspecies characterization of porcine campylobacter coli and campylobacter jejuni by multilocus enzyme electrophoresis typing.enteropathogenic campylobacterjejuni, c. coli and c. lari are currently the most common causes of acute infectious diarrhoeal illness in the uk. many domestic animals, including pigs, act as natural reservoirs of these organisms and infection may occur through the ingestion of contaminated foodstuffs. c jejuni and c. coli, isolated from the livers of bacon pigs, were examined at subspecies level by multilocus enzyme electrophoresis (mee) typing with seven enzymic loci. polymorphological variatio ...200211860082
detection of campylobacter jejuni and campylobacter coli in environmental waters by pcr enzyme-linked immunosorbent assay.a pcr enzyme-linked immunosorbent assay (elisa) assay was applied to the detection of campylobacter jejuni and campylobacter coli in environmental water samples after enrichment culture. bacterial cells were concentrated from 69 environmental water samples by using filtration, and the filtrates were cultured in campylobacter blood-free broth. after enrichment culture, dna was extracted from the samples by using a rapid-boiling method, and the dna extracts were used as a template in a pcr elisa a ...200211872483
identification of campylobacter heat-stable and heat-labile antigens by combining the penner and lior serotyping schemes. 200211880386
application of a 5' nuclease assay for detection of lawsonia intracellularis in fecal samples from pigs.a 5' nuclease assay was developed to detect lawsonia intracellularis in porcine fecal samples. the specific probe and primers were chosen by using the 16s ribosomal dna gene as a target. the 5' nuclease assay was used with a total of 204 clinical samples, and the results were compared to those of immunohistochemistry (im) on ileal sections of the same animals. there was 91% agreement between the results of im and the 5' nuclease assay. in the 5' nuclease assay, 111 (54%) of the pigs tested posit ...200211880427
detection of heat-stable antigens of campylobacter jejuni and c. coli by direct agglutination and passive hemagglutination.the two serotyping schemes for the detection of heat-stable antigens of campylobacter jejuni and campylobacter coli use the same strains for antiserum production but differ in the detection systems used for identifying agglutination. the penner method uses passive hemagglutination (pha) while the laboratory of enteric pathogens method uses the same antisera but in a whole-bacterial-cell direct agglutination (da) protocol. c. jejuni produces a polysaccharide capsule, which is antigenic, and is th ...200211880429
fatal case of campylobacter lari prosthetic joint infection and bacteremia in an immunocompetent patient.campylobacter lari is an infrequent cause of intestinal and extraintestinal infection in humans. we report a case of c. lari prosthetic joint infection and bacteremia in an 81-year-old immunocompetent man. the infection was associated with septic shock and fatal outcome. c. lari may cause severe disease, even in an immunocompetent host.200211880437
identification of motility and autoagglutination campylobacter jejuni mutants by random transposon mutagenesis.campylobacter jejuni has been identified as the leading cause of acute bacterial diarrhea in the united states, yet compared with other enteric pathogens, considerably less is understood concerning the virulence factors of this human pathogen. a random in vivo transposon mutagenesis system was recently developed for the purpose of creating a library of c. jejuni transformants. a total of 1,065 c. jejuni transposon mutants were screened for their ability to swarm on motility agar plates and autoa ...200211895937
helicobacter pylori uses motility for initial colonization and to attain robust infection.helicobacter pylori has been shown to require flagella for infection of the stomach. to analyze whether flagella themselves or motility is needed by these pathogens, we constructed flagellated nonmotile mutants. this was accomplished by using both an insertion mutant and an in-frame deletion of the motb gene. in vitro, these mutants retain flagella (fla(+)) but are nonmotile (mot(-)). by using fvb/n mice, we found that these mutants had reduced ability to infect mice in comparison to that of the ...200211895962
comparative antibiotic resistance of diarrheal pathogens from vietnam and thailand, 1996-1999.antimicrobial resistance rates for shigella, campylobacter, nontyphoidal salmonella, and enterotoxigenic escherichia coli were compared for vietnam and thailand from 1996 to 1999. resistance to trimethoprim-sulfamethoxazole, ampicillin, chloramphenicol, and tetracycline was common. quinolone resistance remains low in both countries, except among campylobacter and salmonella organisms in thailand. nalidixic acid resistance among salmonellae has more than doubled since 1995 (to 21%) in thailand bu ...200211897070
characterization of the campylobacter jejuni heptosyltransferase ii gene, waaf, provides genetic evidence that extracellular polysaccharide is lipid a core independent.campylobacter jejuni produces both lipooligosaccharide (los) and a higher-molecular-weight polysaccharide that is believed to form a capsule. the role of these surface polysaccharides in c. jejuni-mediated enteric disease is unclear; however, epitopes associated with the los are linked to the development of neurological complications. in escherichia coli and salmonella enterica serovar typhimurium the waaf gene encodes a heptosyltransferase, which catalyzes the transfer of the second l-glycero-d ...200211914340
human campylobacteriosis in developing countries.campylobacteriosis is a collective description for infectious diseases caused by members of the bacterial genus campylobacter. the only form of campylobacteriosis of major public health importance is campylobacter enteritis due to c. jejuni and c. coli. research and control efforts on the disease have been conducted more often in developed countries than developing countries. however, because of the increasing incidence, expanding spectrum of infections, potential of hiv-related deaths due to ca ...200211927019
the superoxide dismutase gene sodm is unique to staphylococcus aureus: absence of sodm in coagulase-negative staphylococci.superoxide dismutase (sod) profiles of clinical isolates of staphylococcus aureus and coagulase-negative staphylococci (cons) were determined by using whole-cell lysates and activity gels. all s. aureus clinical isolates exhibited three closely migrating bands of activity as previously determined for laboratory strains of s. aureus: sodm, soda, and a hybrid composed of sodm and soda (m. w. valderas and m. e. hart, j. bacteriol. 183:3399-3407, 2001). in contrast, the cons produced only one sod ac ...200211948161
traditional and molecular techniques for the study of emerging bacterial diseases: one laboratory's perspective.identification of emerging bacterial pathogens generally results from a chain of events involving microscopy, serology, molecular tools, and culture. because of the spectacular molecular techniques developed in the last decades, some authors think that these techniques will shortly supplant culture. the key steps that led to the discovery of emerging bacteria have been reviewed to determine the real contribution of each technique. historically, microscopy has played a major role. serology provid ...200211897062
web-based phylogenetic assignment tool for analysis of terminal restriction fragment length polymorphism profiles of microbial communities.culture-independent dna fingerprints are commonly used to assess the diversity of a microbial community. however, relating species composition to community profiles produced by community fingerprint methods is not straightforward. terminal restriction fragment length polymorphism (t-rflp) is a community fingerprint method in which phylogenetic assignments may be inferred from the terminal restriction fragment (t-rf) sizes through the use of web-based resources that predict t-rf sizes for known b ...200314602639
versatility of aminoglycosides and prospects for their future.aminoglycoside antibiotics have had a major impact on our ability to treat bacterial infections for the past half century. whereas the interest in these versatile antibiotics continues to be high, their clinical utility has been compromised by widespread instances of resistance. the multitude of mechanisms of resistance is disconcerting but also illuminates how nature can manifest resistance when bacteria are confronted by antibiotics. this article reviews the most recent knowledge about the mec ...200312857776
flagellin glycosylation island in pseudomonas syringae pv. glycinea and its role in host specificity.the deduced amino acid sequences of the flagellins of pseudomonas syringae pv. tabaci and p. syringae pv. glycinea are identical; however, their abilities to induce a hypersensitive reaction are clearly different. the reason for the difference seems to depend on the posttranslational modification of the flagellins. to investigate the role of this posttranslational modification in the interactions between plants and bacterial pathogens, we isolated genes that are potentially involved in the postt ...200314594840
molecular structure and evolution of the conjugative multiresistance plasmid pre25 of enterococcus faecalis isolated from a raw-fermented sausage.plasmid pre25 from enterococcus faecalis transfers resistances against kanamycin, neomycin, streptomycin, clindamycin, lincomycin, azithromycin, clarithromycin, erythromycin, roxithromycin, tylosin, chloramphenicol, and nourseothricin sulfate by conjugation in vitro to e. faecalis jh2-2, lactococcus lactis bu2, and listeria innocua l19. its nucleotide sequence of 50237 base pairs represents the largest, fully sequenced conjugative multiresistance plasmid of enterococci (plasmid 46 (2001) 170). t ...200314597005
diversity and succession of the intestinal bacterial community of the maturing broiler chicken.the diversity of bacterial floras in the ilea and ceca of chickens that were fed a vegetarian corn-soy broiler diet devoid of feed additives was examined by analysis of 1,230 partial 16s rrna gene sequences. nearly 70% of sequences from the ileum were related to those of lactobacillus, with the majority of the rest being related to clostridiaceae (11%), streptococcus (6.5%), and enterococcus (6.5%). in contrast, clostridiaceae-related sequences (65%) were the most abundant group detected in the ...200314602645
hazards of healthy living: bottled water and salad vegetables as risk factors for campylobacter infection. 200314609455
characterization of waterborne outbreak-associated campylobacter jejuni, walkerton, ontario. 200314609457
evaluation of the prospect microplate assay for detection of campylobacter: a routine laboratory evaluate the use of the new enzyme-linked immunosorbent assay, the prospect campylobacter microplate assay (alexon-trend, minneapolis, mn, usa), which allows 2-h detection of both campylobacter jejuni and campylobacter coli antigen directly in stool specimens.200314616724
pseudaminic acid, the major modification on campylobacter flagellin, is synthesized via the cj1293 gene.flagellins from campylobacter jejuni 81-176 and campylobacter coli vc167 are heavily glycosylated. the major modifications on both flagellins are pseudaminic acid (pse5ac7ac), a nine carbon sugar that is similar to sialic acid, and an acetamidino-substituted analogue of pseudaminic acid (pseam). previous data have indicated that pseam is synthesized via pse5ac7ac in c. jejuni 81-176, but that the two sugars are synthesized using independent pathways in c. coli vc167. the cj1293 gene of c. jejuni ...200314617187
effect of temperature on viability of campylobacter jejuni and campylobacter coli on raw chicken or pork determine growth and survival of campylobacter jejuni and campylobacter coli on chicken and pork, campylobacter spp. (10(4) cfu/cm2) were inoculated on pieces of raw, irradiated chicken or pork skin and exposed to temperatures ranging from -20 to 42 degrees c under either microaerobic or aerobic conditions. viable counts over 48 h declined 2 to 3 log cfu/cm2 at -20 degrees c and 1 to 2 log cfu/cm2 at 25 degrees c regardless of skin type, species of campylobacter, or level of oxygen. at 4 degr ...200314627278
isolation of campylobacter jejuni and campylobacter coli from the gall bladder samples of sheep and identification by polymerase chain this study, 100 gall bladder samples of sheep slaughtered at an abattoir in elaziğ province were examined for campylobacter jejuni and campylobacter coli by culture and polymerase chain reaction (pcr). preston campylobacter agar supplemented with 7% horse blood and preston selective supplement (oxoid, hampshire, uk) were used for isolation of the agents. campylobacter spp. were isolated in 66 samples, and they were identified as 34% c. jejuni and 32% c. coli. a multiplex pcr based upon the us ...200314629001
antimicrobial resistance in campylobacter jejuni and campylobacter coli strains isolated in 1991 and 2001-2002 from poultry and humans in berlin, germany.the susceptibilities of 430 campylobacter jejuni strains and 79 c. coli strains to six antimicrobial agents were tested and analyzed. the two sets of strains originated from retail market chicken and turkey samples and from humans, respectively, in berlin, germany. two groups of isolates, one dating from 1991 and the other dating from 2001-2002, were tested. of the campylobacter sp. isolates recovered from humans in 2001-2002, 45.1% were resistant to ciprofloxacin, 37.8% were resistant to tetrac ...200314638490
risk factors for sporadic campylobacter jejuni infections in rural michigan: a prospective case-control study.this case-control study investigated risk factors for campylobacteriosis in a rural population. exposure to live farm animals was hypothesized to increase the risk for campylobacter jejuni enteritis.200314652344
genetic diversity of campylobacter jejuni isolates from farm animals and the farm environment.the genetic diversity of campylobacter jejuni isolates from farm animals and their environment was investigated by multilocus sequence typing (mlst). a total of 30 genotypes, defined by allelic profiles (assigned to sequence types [sts]), were found in 112 c. jejuni isolates originating in poultry, cattle, sheep, starlings, and slurry. all but two of these genotypes belonged to one of nine c. jejuni clonal complexes previously identified in isolates from human disease and retail food samples and ...200314660392
survival of helicobacter pylori in a natural freshwater environment.the mode by which helicobacter pylori, the causative agent of most gastric ulcers, is transmitted remains undetermined. epidemiological evidence suggests these organisms are waterborne; however, h. pylori has rarely been grown from potential water sources. this may be due to the ability of this organism to rapidly enter the viable but nonculturable (vbnc) state. our investigation examines the entrance of h. pylori into this state in laboratory cultures and a natural freshwater environment as wel ...200314660399
avian reservoirs and zoonotic potential of the emerging human pathogen helicobacter canadensis.a polyphasic identification approach was used to investigate the taxonomic position of campylobacter-like isolates recovered from barnacle geese (branta leucopsis) and canada geese (branta candensis). seven strains were selected from a collection of 21 isolates and analyzed by extensive phenotypic testing; four strains were characterized by 16s rrna gene sequence analysis. the results clearly identified the bird isolates as helicobacter canadensis, recently described as an emerging human pathoge ...200314660407
risk factors for antibiotic resistance in campylobacter spp. isolated from raw poultry meat in switzerland.the world-wide increase of foodborne infections with antibiotic resistant pathogens is of growing concern and is designated by the world health organization as an emerging public health problem. thermophilic campylobacter have been recognised as a major cause of foodborne bacterial gastrointestinal human infections in switzerland and in many other countries throughout the world. poultry meat is the most common source for foodborne cases caused by campylobacter. because all classes of antibiotics ...200314662013
risk factors associated with campylobacter jejuni infections in curaçao, netherlands antilles.a steady increase in the incidence of guillain-barré syndrome (gbs) with a seasonal preponderance, almost exclusively related to campylobacter jejuni, and a rise in the incidence of laboratory-confirmed campylobacter enteritis have been reported from curaçao, netherlands antilles. we therefore investigated possible risk factors associated with diarrhea due to epidemic c. jejuni. typing by pulsed-field gel electrophoresis identified four epidemic clones which accounted for almost 60% of the infec ...200314662945
applicability of a rapid duplex real-time pcr assay for speciation of campylobacter jejuni and campylobacter coli directly from culture plates.a rapid duplex real-time polymerase chain reaction (pcr) assay for speciation of campylobacter jejuni and campylobacter coli using the abi prism 7700 sequence detection system (applied biosystems) was developed based on two of the genes used in a conventional multiplex pcr. a rapid turnaround time of 3 h was achieved with the use of boiled cell lysates. applicability of the assay was tested with 6015 random campylobacter strains referred to the campylobacter reference unit, with 97.6% being iden ...200314680705
pcr-restriction fragment length polymorphism analysis for detection of point mutations associated with macrolide resistance in campylobacter spp.a 23s rrna gene fragment in domain v was sequenced from 30 clinical isolates of campylobacter spp., including 22 resistant to macrolides. two point mutations associated with erythromycin resistance were identified at positions 2074 and 2075 on the 23s rrna gene (homologous to a2142c and a2143g mutations in helicobacter pylori) in which an adenine residue is also replaced with a cytosine and a guanine residue, respectively. a combined pcr-restriction fragment length polymorphism technique was dev ...200312604552
molecular characterization of fluoroquinolone-resistant campylobacter spp. isolated from poultry.campylobacteriosis, an infectious disease caused by campylobacter jejuni and campylobacter coli, is treated by fluoroquinolone antibiotics in clinical practices. however, use of these drugs in animal husbandry may select for fluoroquinolone-resistant campylobacters and, thereby, compromise the clinical treatment of infection. in this study, 21 fluoroquinolone-resistant campylobacters were isolated from poultry samples. morphological and biochemical characteristics indicated that 19 isolates were ...200312619802
a real-time pcr assay for the detection of campylobacter jejuni in foods after enrichment culture.a real-time pcr assay was developed for the quantitative detection of campylobacter jejuni in foods after enrichment culture. the specificity of the assay for c. jejuni was demonstrated with a diverse range of campylobacter species, related organisms, and unrelated genera. the assay had a linear range of quantification over six orders of magnitude, and the limit of detection was approximately 12 genome equivalents. the assay was used to detect c. jejuni in both naturally and artificially contami ...200312620820
detection and typing of campylobacter jejuni and campylobacter coli and analysis of indicator organisms in three waterborne outbreaks in finland.waterborne outbreaks associated with contamination of drinking water by campylobacter jejuni are rather common in the nordic countries sweden, norway, and finland, where in sparsely populated districts groundwater is commonly used without disinfection. campylobacters, escherichia coli, or other coliforms have rarely been detected in potential sources. we studied three waterborne outbreaks in finland caused by c. jejuni and used sample volumes of 4,000 to 20,000 ml for analysis of campylobacters ...200312620821
comparison of broth microdilution, e test, and agar dilution methods for antibiotic susceptibility testing of campylobacter jejuni and campylobacter coli.a standardized broth microdilution method was compared to the e test and an agar dilution method for the antimicrobial susceptibility testing of campylobacter jejuni and c. coli isolates. a group of 47 human clinical isolates, 37 isolates from retail poultry, and 29 isolates from living turkeys (total, 113 isolates) was included in the study. these encompassed 92 c. jejuni and 21 c. coli strains. the mics of six antimicrobial agents were determined by the broth microdilution and e test methods, ...200312624030
molecular typing of campylobacter jejuni and campylobacter coli. 200312624086
prevalence of campylobacter within a swine slaughter and processing this work, the occurrence of campylobacter in a swine slaughter and processing facility was studied. thirty composite carcass samples, representing 360 swine carcasses, were taken immediately after exsanguination, immediately after polishing, after the final wash, and after overnight chilling at 2 degrees c. thirty matching composite rectal samples were also taken immediately after exsanguination, and 60 nonmatching individual colon samples were collected from the same lot of swine during evi ...200314503704
detection and enumeration of campylobacter jejuni and campylobacter coli by indirect impedimetry with an oxygen scavenging system.six strains of campylobacter jejuni and campylobacter coli were shown to grow in a variety of media, but, with one exception, they were unable to produce sufficient change in the electrical properties of the medium to allow their detection by impedance monitoring. with the use of an indirect method based on absorption of evolved carbon dioxide and a medium containing the oxygen scavenger oxyrase, all strains were detectable, and correlations between time to detection and the logarithm of the ino ...200314503735
disinfectant susceptibility testing of avian and swine campylobacter isolates by a filtration method.the susceptibility testing of disinfectants against campylobacter jejuni and campylobacter coli strains from broilers and pigs was investigated. the filtration method european standard en 1040 was adapted to campylobacter cultures and validated with reference strains. two disinfectants were tested: 1% benzalkonium chloride active matter, as quaternary ammonium compound, and 0.63% sodium hypochlorite as chlorine-releasing agent. both disinfectants were effective against the 34 campylobacter strai ...200314516706
simultaneous detection of mutations associated with resistance to macrolides and quinolones in campylobacter jejuni and c. coli using a pcr-line probe assay.quinolone and macrolide resistance of campylobacter jejuni and campylobacter coli mainly depend on a mutation in gyra and in 23s rdna, respectively. in order to detect quinolone and/or macrolide resistant c. jejuni and c. coli strains, a macrolide and quinolone line probe assay (mq-lipa) was developed and 42 c. jejuni and c. coli strains were tested to evaluate the efficiency of the assay. profiles of the mutations in 23s rdna and in gyra characterized by mq-lipa agreed with resistance to macrol ...200314522100
ribotyping characterisation of campylobacter isolates randomly collected from different sources in this study the potential for using the automated psti ribotyping as a primary library typing method to survey campylobacter and for identification of two thermophilic campylobacter jejuni and campylobacter coli species was evaluated. a total of 158 isolates randomly collected in italy from different sources were analyzed. a large percentage of chicken (28%), turkey (27%) and turkey meat (25%) isolates shared their ribotyping profiles (ribotypes) with those of humans, whereas the swine isolate ...200314522511
the iron-responsive regulator fur is transcriptionally autoregulated and not essential in neisseria meningitidis.fur is a well-known iron-responsive repressor of gene transcription, which is used by many bacteria to respond to the low-iron environment that pathogens encounter during infection. the fur gene in neisseria meningitidis has been described as an essential gene that may regulate a broad array of genes. we succeeded in obtaining an n. meningitidis mutant with the fur gene knocked out and used it to undertake studies of fur-mediated iron regulation. we show that expression of both fur and the trans ...200314526014
comparison of the bax system with a multiplex pcr method for simultaneous detection and identification of campylobacter jejuni and campylobacter coli in environmental samples.the campylobacter detection is performed by conventional culture methods and the identification of campylobacter jejuni and campylobacter coli is principally based on the hippurate hydrolysis test. the two major drawbacks of this biochemical test for species identification include the inconsistency of the results and the presence of atypical strains, which can lead to the misidentification of an isolate. as an alternative, multiplex polymerase chain reaction (mpcr) protocols for the simultaneous ...200314527799
application of host-specific bacteriophages to the surface of chicken skin leads to a reduction in recovery of campylobacter jejuni.retail poultry products are widely purported as the major infection vehicle for human campylobacteriosis. numerous intervention strategies have sought to reduce campylobacter contamination on broiler carcasses in the abattoir. this study reports the efficacy of bacteriophage in reducing the number of recoverable campylobacter jejuni cells on artificially contaminated chicken skin.200314532096
comparison of campylobacter isolates from poultry and humans: association between in vitro virulence properties, biotypes, and pulsed-field gel electrophoresis clusters.the in vitro virulence properties of 197 temporally and geographically related campylobacter isolates from chicken broilers and humans were compared. comparisons of the virulence properties associated with genotypes and biotypes were made. all isolates adhered to, and 63% invaded, int-407 cells, whereas 13% were cytotoxic for cho cells. cho cell-cytotoxic extracts were also cytotoxic for int-407 cells, but the sensitivity for vero cells was variable. the proportion of isolates demonstrating a hi ...200314532099
antimicrobial resistance in campylobacter from broilers: association with production type and antimicrobial use.the isolation and antimicrobial resistance of campylobacter jejuni and campylobacter coli strains from broilers arriving in french slaughterhouses, were analysed according to production types (i.e. standard, export or free-range) and antimicrobial (i.e. coccidiostats, growth promoters or therapeutic agents) administration in flocks. prevalence was 56.6% in standard, 51.3% in export and 80.0% in free-range broilers. three hundred and ninety-three strains were identified. two-thirds of the strains ...200314559174
deletion of helicobacter pylori vacuolating cytotoxin gene by introduction of directed construct a vaca-knockout helicobacter pylori mutant strain, whose only difference from the wild strain is its disrupted vaca gene.200314562387
routes for campylobacter contamination of poultry meat: epidemiological study from hatchery to slaughterhouse.from april 1998 to march 2000, 18 broiler flocks were followed from the hatchery to the slaughterhouse. campylobacter was not found in the hatchery, 1-day-old chicks or in the rearing house before the arrival of the chicks. the infection of broiler flocks increased continuously during the rearing time, with a total of seven positive flocks at the end of rearing. farms with campylobacter-positive broilers were characterized by the circulation of campylobacter in the environment (puddles, dung hil ...200314959785
fluoroquinolone-resistant campylobacter in animal reservoirs: dynamics of development, resistance mechanisms and ecological fitness.thermophilic campylobacter species, including campylobacter jejuni and campylobacter coli, are responsible for foodborne campylobacteriosis in humans and are increasingly resistant to fluoroquinolone (fq) antimicrobials. the therapeutic use of fq antimicrobial agents in food animal production, particularly in poultry, has become a concern for public health, because the practice may promote the emergence of fq-resistant campylobacter that can be transmitted to humans through the food chain. recen ...200315134291
birds, migration and emerging zoonoses: west nile virus, lyme disease, influenza a and enteropathogens.wild birds are important to public health because they carry emerging zoonotic pathogens, either as a reservoir host or by dispersing infected arthropod vectors. in addition, bird migration provides a mechanism for the establishment of new endemic foci of disease at great distances from where an infection was acquired. birds are central to the epidemiology of west nile virus (wnv) because they are the main amplifying host of the virus in nature. the initial spread of wnv in the u.s. along the ea ...200315931279
cecal colonization of chicks by bovine-derived strains of campylobacter.campylobacter jejuni and campylobacter coli strains were isolated from feces of dairy cattle at farms with no known problem due to campylobacteria. farms were located in the northeast, desert southwest, and pacific west. twenty isolates were identified by ribotyping with a riboprinter. the ability of these bovine isolates to colonize the ceca of chicks was determined by challenge inoculation and reisolation of the challenge strain from the ceca at 1 and 2 wk after challenge. isolates recovered f ...200314708992
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