TitleAbstractYear(sorted ascending)
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
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
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
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
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
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
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
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
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
development and application of a new scheme for typing campylobacter jejuni and campylobacter coli by pcr-based restriction fragment length polymorphism analysis.a molecular typing approach for campylobacter jejuni and campylobacter coli was developed with restriction fragment length polymorphism analysis of a 9.6-kb pcr-amplified portion of the lipopolysaccharide gene cluster. sixty-one penner serotype reference strains were analyzed with this new genotyping scheme, and 32 genogroups were found. eleven additional genogroups were obtained from 87 clinical c. jejuni strains tested. this molecular typing method shows a correlation with the penner heat-stab ...200211980961
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
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
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
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
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
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
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
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
comparison of rheumatological and gastrointestinal symptoms after infection with campylobacter jejuni/coli and enterotoxigenic escherichia estimate the incidence of postinfectious joint complaints after campylobacter jejuni/coli enteritis compared with enteritis caused by enterotoxigenic e coli (etec). to compare gastrointestinal symptoms, antibiotic treatment, and antibody levels among patients with and without joint symptoms.200211959770
detection of campylobacter jejuni and campylobacter coli in foods by enrichment culture and polymerase chain reaction enzyme-linked immunosorbent assay.a polymerase chain reaction (pcr) assay based on a solution hybridization format with colorimetric end-point detection (pcr elisa) was investigated for the specific detection of campylobacter jejuni and campylobacter coli in food samples following enrichment culture. one hundred fifteen samples of raw meat and offal (poultry, porcine, ovine, and bovine), raw shellfish, and artificially contaminated milk were enriched in blood-free campylobacter enrichment broth for 48 h. enrichment cultures were ...200212030285
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
comparison of 23s polymerase chain reaction-restriction fragment length polymorphism and amplified fragment length polymorphism techniques as typing systems for thermophilic this study, we evaluated the combination of polymerase chain reaction-restriction fragment length polymorphism (pcr-rflp) and amplified fragment length polymorphism (aflp) molecular typing techniques for the analysis of thermophilic campylobacter species isolated from clinical and poultry samples. 23s pcr-rflp analysis performed to fingerprint 69 strains exhibited an excellent level of typability. eleven different types were defined at 100% linkage level following numerical analysis of band p ...200212052557
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
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
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
identification of campylobacter heat-stable and heat-labile antigens by combining the penner and lior serotyping schemes. 200211880386
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
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
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
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
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
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
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
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
molecular evolution of human immunodeficiency virus env in humans and monkeys: similar patterns occur during natural disease progression or rapid virus passage.neonatal rhesus macaque 95-3 was inoculated with nonpassaged simian-human immunodeficiency virus strain shiv-vpu(+), which encodes env of the laboratory-adapted human immunodeficiency virus (hiv) strain iiib and is considered nonpathogenic. cd4(+) t-cell counts dropped to <200 cells/microl within 4.6 years, and monkey 95-3 died with opportunistic infections 5.9 years postinoculation. transfer of blood from 95-3 to two naive adult macaques resulted in high peak viral loads and rapid, persistent t ...200211967343
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
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
cecal colonization of chicks by porcine strains of campylobacter coli.ten genotypically distinct strains of campylobacter coli were isolated from a swine production facility. these porcine isolates were then orally inoculated into day-of-hatch leghorn chicks and were excellent colonizers of the chick cecum. campylobacter coli recovered from inoculated chickens were genotypically identical to the challenge strain. the absence of host specificity suggests a possible movement of strains among swine, field animals and birds, and poultry houses.200212061661
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
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
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
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
[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
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
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
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
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
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
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
in vivo tracking of campylobacter jejuni by using a novel recombinant expressing green fluorescent protein.campylobacter jejuni is a leading cause of food-borne disease in developed countries. the goal of this study was to develop a plasmid-based reporter system with green fluorescent protein (gfp) to facilitate the study of c. jejuni in a variety of niches. c. jejuni transformants harboring the pmek91 gfp gene (gfp)-containing vector were readily detectable by both fluorescence microscopy and flow cytometry. given the ease of detecting these organisms, additional experiments were performed in which ...200312732559
antimicrobial-resistant campylobacter species from retail raw meats.the antimicrobial susceptibilities of 378 campylobacter isolates were determined. resistance to tetracycline was the most common (82%), followed by resistance to doxycycline (77%), erythromycin (54%), nalidixic acid (41%), and ciprofloxacin (35%). campylobacter coli displayed significantly higher rates of resistance to ciprofloxacin and erythromycin than campylobacter jejuni, and campylobacter isolates from turkey meat showed a greater resistance than those from chicken meat.200312732579
usefulness of the microseq 500 16s ribosomal dna-based bacterial identification system for identification of clinically significant bacterial isolates with ambiguous biochemical profiles.due to the inadequate automation in the amplification and sequencing procedures, the use of 16s rrna gene sequence-based methods in clinical microbiology laboratories is largely limited to identification of strains that are difficult to identify by phenotypic methods. in this study, using conventional full-sequence 16s rrna gene sequencing as the "gold standard," we evaluated the usefulness of the microseq 500 16s ribosomal dna (rdna)-based bacterial identification system, which involves amplifi ...200312734240
phenotypic and genotypic differentiation of campylobacter spp. isolated from austrian broiler farms: a identification scheme based on restriction fragment length polymorphism of polymerase chain reaction products (pcr-rflp) was developed to differentiate isolates of the genera campylobacter, arcobacter and helicobacter. based on the 16s rrna gene of these genera, pcr amplified a 1216-bp fragment. the amplicons were digested with the restriction enzymes rsai and ecorv. additional differentiation was obtained using a pcr-assay based on the hippuricase gene. genotyping was performed on several re ...200312745378
evaluation of broiler litter with reference to the microbial composition as assessed by using 16s rrna and functional gene markers.very little is known about the microbial composition of animal bedding wastes, including poultry litter, and what is known has been deduced from standard culture methods, by which some fastidious organisms that exist in the environment may not be detected. we evaluated the bacterial composition of poultry litter by using a combination of culture and molecular detection. total aerobic bacteria in poultry litter were detected by culture at 10(9) cfu/g of material. enteric bacteria such as enteroco ...200312571010
pcr detection of seven virulence and toxin genes of campylobacter jejuni and campylobacter coli isolates from danish pigs and cattle and cytolethal distending toxin production of the study the prevalence of seven virulence and toxin genes, and cytolethal distending toxin (cdt) production of campylobacter jejuni and c. coli isolates from danish pigs and cattle.200312752808
antimicrobial resistance of campylobacter jejuni subsp. jejuni strains isolated from humans in 1998 to 2001 in montréal, canada.the rates of resistance of 51 to 72 human strains of campylobacter jejuni subsp. jejuni isolated annually from 1998 to 2001 in montréal, québec, canada, varied from 1 to 12% for erythromycin, 43 to 68% for tetracycline, and 10 to 47% for ciprofloxacin. in the last years of the study, there was a significant increase in the rate of resistance to ciprofloxacin (p = 0.00003) but not in the rate of resistance to erythromycin (p = 0.056) or tetracycline (p = 0.095) compared to the rate obtained in th ...200312760892
campylobacter--a tale of two protein glycosylation glycosylation is a universal modification of proteins in eukarya, archaea and bacteria. two recent publications describe the first confirmed report of a bacterial n-linked glycosylation pathway in the human gastrointestinal pathogen campylobacter jejuni. in addition, an o-linked glycosylation pathway has been identified and characterized in c. jejuni and the related species campylobacter coli. both pathways have similarity to the respective n- and o-linked glycosylation proces ...200312781527
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
rapid detection of campylobacter coli, c. jejuni, and salmonella enterica on poultry carcasses by using pcr-enzyme-linked immunosorbent assay.contamination of retail poultry by campylobacter spp. and salmonella enterica is a significant source of human diarrheal disease. isolation and identification of these microorganisms require a series of biochemical and serological tests. in this study, campylobacter ceue and salmonella inva genes were used to design probes in pcr-enzyme-linked immunosorbent assay (elisa), as an alternative to conventional bacteriological methodology, for the rapid detection of campylobacter jejuni, campylobacter ...200312788755
prevalence of cytolethal distending toxin production in periodontopathogenic bacteria.cytolethal distending toxin (cdt) is a newly identified virulence factor produced by several pathogenic bacteria implicated in chronic infection. seventy three strains of periodontopathogenic bacteria were examined for the production of cdt by a hela cell bioassay and for the presence of the cdt gene by pcr with degenerative oligonucleotide primers, which were designed based on various regions of the escherichia coli and campylobacter cdtb genes, which have been successfully used for the identif ...200312682119
investigation of infectious agents associated with arthritis by reverse transcription pcr of bacterial reactive and postinfectious arthritis the joints are generally sterile but the presence of bacterial antigens and nucleic acids has been reported. to investigate whether organisms traffic to affected joints in these conditions, we performed reverse transcription pcr using universal primers to amplify any bacterial 16s rrna sequences present in synovial fluid. bacterial sequences were detected in most cases, even after treatment of the synovial fluid with dnase, implying the presence of bacter ...200312716447
investigation of infectious agents associated with arthritis by reverse transcription pcr of bacterial reactive and postinfectious arthritis the joints are generally sterile but the presence of bacterial antigens and nucleic acids has been reported. to investigate whether organisms traffic to affected joints in these conditions, we performed reverse transcription pcr using universal primers to amplify any bacterial 16s rrna sequences present in synovial fluid. bacterial sequences were detected in most cases, even after treatment of the synovial fluid with dnase, implying the presence of bacter ...200312716447
species-specific identification of campylobacters by partial 16s rrna gene sequencing.species-specific identification of campylobacters is problematic, primarily due to the absence of suitable biochemical assays and the existence of atypical strains. 16s rrna gene (16s rdna)-based identification of bacteria offers a possible alternative when phenotypic tests fail. therefore, we evaluated the reliability of 16s rdna sequencing for the species-specific identification of campylobacters. sequence analyses were performed by using almost 94% of the complete 16s rrna genes of 135 phenot ...200312791878
natural transformation of campylobacter jejuni requires components of a type ii secretion system.the human pathogen campylobacter jejuni is one of more than 40 naturally competent bacterial species able to import macromolecular dna from the environment and incorporate it into their genomes. however, in c. jejuni little is known about the genes involved in this process. we used random transposon mutagenesis to identify genes that are required for the transformation of this organism. we isolated mutants with insertions in 11 different genes; most of the mutants are affected in the dna uptake ...200312949093
detection of conserved n-linked glycans and phase-variable lipooligosaccharides and capsules from campylobacter cells by mass spectrometry and high resolution magic angle spinning nmr spectroscopy.glycomics, the study of microbial polysaccharides and genes responsible for their formation, requires the continuous development of rapid and sensitive methods for the identification of glycan structures. in this study, methods for the direct analysis of sugars from 108 to 1010 cells are outlined using the human gastrointestinal pathogen, campylobacter jejuni. using capillary-electrophoresis coupled with sensitive electrospray mass spectrometry, we demonstrate variability in the lipid a componen ...200312716884
inhibition of helicobacter pylori growth in vitro by bulgarian propolis: preliminary report.bee glue (propolis) possesses antimicrobial, anti-inflammatory, anaesthetic and immunostimulating activities. the aim of the study was to evaluate the inhibitory effect of bulgarian propolis on helicobacter pylori growth in vitro. activity of 30% ethanolic extract of propolis (eep) against 38 clinical isolates of h. pylori was evaluated by using the agar-well diffusion method. ethanol was used as a control. in addition, the effect of propolis on the growth of 26 h. pylori and 18 campylobacter st ...200312721318
reduction of bacteria on pork carcasses associated with chilling addition to reducing the temperature of pork carcasses immediately after slaughter and before fabrication, blast chilling (snap chill) or conventional chilling can reduce bacterial populations associated with fresh meats. however, there is little information on bacteria survival resulting from the freeze or chill injury of meat products. in this study, porcine fecal slurries with and without pathogens (listeria monocytogenes, salmonella typhimurium, and campylobacter coli) were inoculated ont ...200312801003
comparison of eight phenotypic methods for subspecies characterization of thermophilic campylobacter spp. isolated from pig liver.four hundred pork livers from bacon pigs (37 herds) obtained at six pig-processing plants were studied to assess the campylobacter contamination rate. deep tissue areas were sampled immediately after evisceration. approximately 6% of livers were infected with campylobacter spp., including campylobacter coli (67%), campylobacter jejuni (30%), and campylobacter lari (3%). the 60 resulting isolates (39 c. coli isolates, 19 c. jejuni isolates, and 2 c. lari isolates) employed in this study were char ...200312801013
specific detection of arcobacter and campylobacter strains in water and sewage by pcr and fluorescent in situ hybridization.the aim of this study was to evaluate pcr and fluorescent in situ hybridization (fish) techniques for detecting arcobacter and campylobacter strains in river water and wastewater samples. both 16s and 23s rrna sequence data were used to design specific primers and oligonucleotide probes for pcr and fish analyses, respectively. in order to assess the suitability of the methods, the assays were performed on naturally and artificially contaminated samples and compared with the isolation of cells on ...200312571045
sources of campylobacter colonization in broiler chickens. 200312902214
use of pcr for direct detection of campylobacter species in bovine feces.this study reports on the use of pcr to directly detect and distinguish campylobacter species in bovine feces without enrichment. inhibitors present in feces are a major obstacle to using pcr to detect microorganisms. the qiaamp dna stool minikit was found to be an efficacious extraction method, as determined by the positive amplification of internal control dna added to bovine feces before extraction. with nested or seminested multiplex pcr, campylobacter coli, c. fetus, c. hyointestinalis, and ...200312788747
antibiotic susceptibility of campylobacter jejuni and campylobacter coli human isolates from bosnia and herzegovina. 200312654755
antimicrobial resistance of campylobacter jejuni and campylobacter coli isolates from broiler chickens isolated at an irish poultry processing plant.the antibiotic susceptibility of campylobacter jejuni and campylobacter coli isolates from broiler chickens were determined in order to evaluate the level of antibiotic resistance of campylobacter species in the irish poultry industry.200312680938
sequence analysis of a cryptic plasmid pcj419 from campylobacter jejuni and construction of an escherichia coli-campylobacter shuttle vector.a small cryptic plasmid, pcj419, was identified in a human clinical isolate of campylobacter jejuni, cloned and sequenced. pcj419 is a circular molecule of 4013 bp with a g+c content of 27.1%. the products of four open reading frames (orfs) share significant sequence similarity with putative proteins from known c. jejuni and campylobacter coli plasmids. orf-1 encodes a putative mobilisation protein (mob). orf-2 and orf-3 encode proteins that have high identity to putative repa and repb proteins, ...200312932741
in vitro activities of new fluoroquinolones against campylobacter jejuni and campylobacter coli isolates obtained from humans in 1980 to 1982 and 1997 to 2001.the antibacterial activities of three newly developed fluoroquinolones (gatifloxacin, levofloxacin, and moxifloxacin) against a total of 307 gastrointestinal human isolates of campylobacter jejuni and campylobacter coli collected during 1980 to 1982 and 1997 to 2001 were examined and compared to those of ciprofloxacin and the unrelated antibacterial agents, clarithromycin, erythromycin, and tetracycline by using the agar plate dilution method. all of the fluoroquinolones exhibited a good activit ...200312936999
development of a sensitive dna microarray suitable for rapid detection of campylobacter spp.campylobacter is the most common cause of human acute bacterial gastroenteritis worldwide, widely distributed and isolated from human clinical samples as well as from many other different sources. to comply with the demands of consumers for food safety, there is a need for development of a rapid, sensitive and specific detection method for campylobacter. in this study, we present the development of a novel sensitive dna-microarray based detection method, evaluated on campylobacter and non-campyl ...200312944122
toward an international standard for pcr-based detection of food-borne thermotolerant campylobacters: assay development and analytical part of a european research project (food-pcr), we developed a standardized and robust pcr detection assay specific for the three most frequently reported food-borne pathogenic campylobacter species, c. jejuni, c. coli, and c. lari. fifteen published and unpublished pcr primers targeting the 16s rrna gene were tested in all possible pairwise combinations, as well as two published primers targeting the 23s rrna gene. a panel of 150 strains including target and nontarget strains was used in an ...200312957958
toward an international standard for pcr-based detection of food-borne thermotolerant campylobacters: validation in a multicenter collaborative part of a european research project, the performance of a pcr assay to detect food-borne thermotolerant campylobacters (campylobacter jejuni, c. coli, and c. lari) was evaluated through an international collaborative trial involving 12 participating laboratories. dna from 10 target and 8 nontarget strains was tested, and the results were reported as the presence of a positive signal after gel electrophoresis. the overall inclusivity (sensitivity) was 93.7%, and the exclusivity (specificity) w ...200312957959
microarray-based identification of thermophilic campylobacter jejuni, c. coli, c. lari, and c. upsaliensis.dna microarrays are an excellent potential tool for clinical microbiology, since this technology allows relatively rapid identification and characterization of microbial and viral pathogens. in the present study, an oligonucleotide microarray was developed and used for the analysis of thermophilic campylobacter spp., the primary food-borne pathogen in the united states. we analyzed four campylobacter species: campylobacter jejuni, c. coli, c. lari, and c. upsaliensis. our assay relies on the pcr ...200312958228
production of cytolethal distending toxins by pathogenic escherichia coli strains isolated from human and animal sources: establishment of the existence of a new cdt variant (type iv).three types of cytolethal distending toxin (cdt), namely, cdt-i, cdt-ii, and cdt-iii, have been described in escherichia coli. using primers designed for the detection of sequences common to the cdtb genes, we analyzed by pcr a set of 21 cdt-producing e. coli strains of intestinal and extraintestinal origins isolated from human and different animal species in several european countries and in the united states. on the basis of the existing differences in the cdtb genes, cdt-i-, cdt-ii-, and cdt- ...200312958258
the complete genome sequence of the carcinogenic bacterium helicobacter hepaticus.helicobacter hepaticus causes chronic hepatitis and liver cancer in mice. it is the prototype enterohepatic helicobacter species and a close relative of helicobacter pylori, also a recognized carcinogen. here we report the complete genome sequence of h. hepaticus atcc51449. h. hepaticus has a circular chromosome of 1,799,146 base pairs, predicted to encode 1,875 proteins. a total of 938, 953, and 821 proteins have orthologs in h. pylori, campylobacter jejuni, and both pathogens, respectively. h. ...200312810954
helicobacter pylori preferentially induces interleukin 12 (il-12) rather than il-6 or il-10 in human dendritic cells.dendritic cells are potent antigen-presenting cells that are present in the gastrointestinal tract and are required for the induction of a th1 t-cell acquired immune response. since infection with the gastric pathogen helicobacter pylori elicits a th1 cell response, the interaction of these organisms with dendritic cells should reflect the th1 bias. we incubated h. pylori with cultured human dendritic cells and measured the cytokine induction profile, comparing the response to that induced by sa ...200312819109
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
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