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susceptibility of campylobacter jejuni and campylobacter coli isolated from animals and humans to ciprofloxacin.fifty five thermophilic campylobacter spp. strains were isolated from the caecum of broilers, cecum and colon of pigs and from human faeces. the strains were identified as campylobacter jejuni and campylobacter coli. the more prevalent species in humans and broilers was campylobacter jejuni, and in pigs campylobacter coli. in the framework of this study, sensitivity to ciprofloxacin in isolated strains of campylobacter jejuni and campylobacter coli was tested by e-test. resistant to ciprofloxaci ...200919645360
the response of campylobacter jejuni to low temperature differs from that of escherichia coli.human infection with campylobacter jejuni is often associated with the consumption of foods that have been exposed to both chilling and high temperatures. despite the public health importance of this pathogen, little is known about the effects of cold exposure on its ability to survive a subsequent heat challenge. this work examined the effect of rapid exposure to chilling, as would occur in poultry processing, on the heat resistance at 56 degrees c of two c. jejuni strains, 11168 and 2097e48, a ...200919648365
novel clonal complexes with an unknown animal reservoir dominate campylobacter jejuni isolates from river water in new zealand.campylobacter jejuni is widely distributed in the environment, and river water has been shown to carry high levels of the organism. in this study, 244 c. jejuni isolates from three river catchment areas in new zealand were characterized using multilocus sequence typing. forty-nine of the 88 sequence types identified were new. the most common sequence types identified were st-2381 (30 isolates), st-45 (25 isolates), and st-1225 (23 isolates). the majority of the sequence types identified in the r ...200919648367
amoxicillin therapy of poultry flocks: effect upon the selection of amoxicillin-resistant commensal campylobacter spp.the aim of this study was to investigate the effect of amoxicillin therapy of poultry flocks upon the persistence of commensal campylobacter spp. and the incidence of antibiotic resistance.200919656785
campylobacter coli prosthetic hip infection associated with ingestion of contaminated oysters.this report describes the first reported case of a prosthetic hip joint infection due to campylobacter coli. the infection presumably resulted from ingestion of contaminated raw oysters. issues regarding original smear interpretation, culture isolation, and susceptibility testing are presented.200919656982
efflux-mediated drug resistance in bacteria: an update.drug efflux pumps play a key role in drug resistance and also serve other functions in bacteria. there has been a growing list of multidrug and drug-specific efflux pumps characterized from bacteria of human, animal, plant and environmental origins. these pumps are mostly encoded on the chromosome, although they can also be plasmid-encoded. a previous article in this journal provided a comprehensive review regarding efflux-mediated drug resistance in bacteria. in the past 5 years, significant pr ...200919678712
spatiotemporal homogeneity of campylobacter subtypes from cattle and sheep across northeastern and southwestern scotland.source attribution using molecular subtypes has implicated cattle and sheep as sources of human campylobacter infection. whether the campylobacter subtypes associated with cattle and sheep vary spatiotemporally remains poorly known, especially at national levels. here we describe spatiotemporal patterns of prevalence, bacterial enumeration, and subtype composition in campylobacter isolates from cattle and sheep feces from northeastern (63 farms, 414 samples) and southwestern (71 farms, 449 sampl ...200919700557
molecular, antigenic, and functional characteristics of ferric enterobactin receptor cfra in campylobacter jejuni.the ferric enterobactin receptor cfra not only is responsible for high-affinity iron acquisition in campylobacter jejuni but also is essential for c. jejuni colonization in animal intestines. in this study, we determined the feasibility of targeting the iron-regulated outer membrane protein cfra for immune protection against campylobacter colonization. alignment of complete cfra sequences from 15 campylobacter isolates showed that the levels of amino acid identity for cfra range from 89% to 98%. ...200919737895
genetic diversity and stability of the pora allele as a genetic marker in human campylobacter infection.the major outer-membrane protein (momp) of campylobacter jejuni and campylobacter coli, encoded by the pora gene, is extremely genetically diverse. conformational momp epitopes are important in host immunity, and variation in surface-exposed regions probably occurs as a result of positive immune selection during infection. pora diversity has been exploited in genotyping studies using highly discriminatory nucleotide sequences to identify potentially epidemiologically linked cases of human campyl ...200919744989
cost analysis and antimicrobial susceptibility testing comparing the e test and the agar dilution method in campylobacter jejuni and campylobacter coli.although numerous reports have compared the antimicrobial susceptibility of campylobacter spp., controversy still exists about the use of the e test as an alternative to the agar dilution method suggested by the clinical and laboratory standards institute. mics of 8 antimicrobials were determined using the e test and agar dilution methods for 103 campylobacter jejuni and campylobacter coli isolates from fresh chicken randomly purchased from stores in 3 southern ontario counties. overall, 72.6% o ...200919748428
functional characterization of flagellin glycosylation in campylobacter jejuni 81-176.the major flagellin of campylobacter jejuni strain 81-176, flaa, has been shown to be glycosylated at 19 serine or threonine sites, and this glycosylation is required for flagellar filament formation. some enzymatic components of the glycosylation machinery of c. jejuni 81-176 are localized to the poles of the cell in an flhf-independent manner. flagellin glycosylation could be detected in flagellar mutants at multiple levels of the regulatory hierarchy, indicating that glycosylation occurs inde ...200919749047
mouse intestine colonization ability of campylobacter coli strains.campylobacter coli is an etiological agent of gastrointestinal and extraintestinal infections in man and animals, and can be found as a commensal in gastrointestinal tract of animals. in this study, we aimed to determine differences among c coli strains in colonization of the intestinal tract of mice. seven c coli strains isolated from diarrheic patients, asymptomatic hosts and chicken carcasses were used for this study. each strain was inoculated with 0.1 ml of a bacterial suspension (3 x 10(8) ...200919753795
thermotolerant coliforms are not a good surrogate for campylobacter spp. in environmental water.this study aimed to assess the importance of quantitatively detecting campylobacter spp. in environmental surface water. the prevalence and the quantity of campylobacter spp., thermotolerant coliforms, and escherichia coli in 2,471 samples collected weekly, over a 2-year period, from 13 rivers and 12 streams in the eastern townships, québec, canada, were determined. overall, 1,071 (43%), 1,481 (60%), and 1,463 (59%) samples were positive for campylobacter spp., thermotolerant coliforms, and e. c ...200919734335
functional analysis of the helicobacter pylori flagellar switch proteins.helicobacter pylori uses flagellum-mediated chemotaxis to promote infection. bacterial flagella change rotational direction by changing the state of the flagellar motor via a subcomplex referred to as the switch. intriguingly, the h. pylori genome encodes four switch complex proteins, flim, flin, fliy, and flig, instead of the more typical three of escherichia coli or bacillus subtilis. our goal was to examine whether and how all four switch proteins participate in flagellation. previous work de ...200919767432
prevalence of campylobacter spp. in raw retail poultry on sale in northern ireland.a year-long survey of fresh, retail poultry products on sale in northern ireland was undertaken to define the prevalence of campylobacter spp. by using protocols based on iso (standard) 10272-1:2006. incubation at 37 and 42 degrees c was undertaken to increase the diversity of isolates obtained. overall, 652 isolates were identified as campylobacter spp. by using pcr and amplified fragment length polymorphic typing. phenotyping wrongly identified 21% of isolates. prevalences of campylobacter fou ...200919777882
campylobacter species occurrence within internal organs and tissues of commercial caged leghorn laying hens.campylobacter spp. are frequently present in the intestinal tract and internal tissues of broiler breeder and broiler chickens. campylobacter spp. ecology in commercial leghorn laying hens has not been extensively studied. the objectives of the current study were to determine 1) campylobacter spp. presence in the reproductive tract, lymphoid organs, liver-gallbladder, and ceca of commercial leghorn laying hens; 2) species of campylobacter present; and 3) antimicrobial resistance pattern of campy ...200919834099
characterization of the oxidative stress stimulon and perr regulon of campylobacter jejuni.during gut colonization, the enteric pathogen campylobacter jejuni must surmount the toxic effects of reactive oxygen species produced by its own metabolism, the host immune system, and intestinal microflora. elucidation of c. jejuni oxidative stress defense mechanisms is critical for understanding campylobacter pathophysiology.200919835633
campylobacter excreted into the environment by animal sources: prevalence, concentration shed, and host association.an intensive study of 443 isolates of campylobacter jejuni and campylobacter coli from 2031 fecal samples excreted by animal sources including cattle, sheep, and pigs, a range of wild and domesticated avian species and pets is described. the prevalence found in the majority of animal sources ranged from 22% to 28% with poultry being highest at 41% and cats and dogs lowest (<5%). the average count excreted for each animal source was found not to be significantly different ranging from approximate ...200919839759
efficacy of mini vidas for the detection of campylobacter spp. from retail broiler meat enriched in bolton broth, with or without the supplementation of blood.the goals of this study were to evaluate the efficacy of the mini vidas automated immunoassay chemistry system to detect campylobacter spp. from retail broiler meat enriched in bolton broth supplemented with lysed blood (b+b) or without blood (b-b), and to detect positive samples at 24 versus 48 h after enrichment. retail broiler meat was enriched and tested for campylobacter spp. with the mini vidas and with an agar plate. isolates were speciated with a multiplex pcr and typed with pulsed-field ...200919903413
helicobacter pylori lipopolysaccharide modification, lewis antigen expression, and gastric colonization are cholesterol-dependent.helicobacter pylori specifically takes up cholesterol and incorporates it into the bacterial membrane, yet little is currently known about cholesterol's physiological roles. we compared phenotypes and in vivo colonization ability of h. pylori grown in a defined, serum-free growth medium, f12 with 1 mg/ml albumin containing 0 to 50 mug/ml cholesterol.200920003432
the hemolytic and cytolytic activities of serratia marcescens phospholipase a (phla) depend on lysophospholipid production by phla.serratia marcescens is a gram-negative bacterium and often causes nosocomial infections. there have been few studies of the virulence factors of this bacterium. the only s. marcescens hemolytic and cytotoxic factor reported, thus far, is the hemolysin shla.200920003541
easy-to-use rapid test for direct detection of campylobacter spp. in chicken feces.human campylobacteriosis is the leading cause of acute bacterial gastroenteritis in developed countries. one important source of infection is poultry. results from the dutch campylobacter risk management and assessment project indicate that meat from broiler flocks shedding >or=7 log cfu campylobacter per g of feces poses the greatest risk of transmitting campylobacteriosis. the objective of this study was to develop a simple and rapid test that would identify chicken flocks shedding high number ...200920003729
long-term survival of campylobacter jejuni at low temperatures is dependent on polynucleotide phosphorylase activity.campylobacter jejuni is a leading cause of bacterial gastroenteritis worldwide. infection generally occurs after ingestion of contaminated poultry products, usually conserved at low temperatures. the mechanisms promoting survival of c. jejuni in the cold remain poorly understood despite several investigations. the present study provides insight into the survival mechanism by establishing the involvement of polynucleotide phosphorylase (pnpase), a 3'-5' exoribonuclease with multiple biological fu ...200919801468
description and sources of contamination by campylobacter spp. of river water destined for human consumption in brittany, france.presence or absence of campylobacter spp. in water of five rivers upstream from an intake point for drinking water production was investigated, and isolates genetically compared with human, pig and poultry isolates in order to determine their source. river water and drinking water obtained from these rivers were sampled one time per month, over a period of one year, and tested for campylobacter. isolates were typed by pfge. campylobacter was not detected in treated drinking water, but 50% of the ...200919942377
prevalence and risk factor investigation of campylobacter species in beef cattle feces from seven large commercial feedlots in alberta, canada.this fecal prevalence study targeted cattle from 7 large (10,000 to > 40,000 head) commercial feedlots in alberta as a means of establishing campylobacter levels in cattle just prior to animals entering the food chain. overall, 87% [95% confidence interval (ci) = 86-88] of 2776 fresh pen-floor fecal samples were culture positive for campylobacter species, with prevalences ranging from 76% to 95% among the 7 feedlots. campylobacter spp. prevalence was 88% (95% ci = 86-90) in the summer (n = 1376) ...200920046629
dynamics of campylobacter colonization of a natural host, sturnus vulgaris (european starling).wild european starlings (sturnus vulgaris) shed campylobacter at high rates, suggesting that they may be a source of human and farm animal infection. a survey of campylobacter shedding of 957 wild starlings was undertaken by culture of faecal specimens and genetic analysis of the campylobacters isolated: shedding rates were 30.6% for campylobacter jejuni, 0.6% for c. coli and 6.3% for c. lari. genotyping by multilocus sequence typing (mlst) and antigen sequence typing established that these bact ...200918826435
can campylobacter coli induce guillain-barré syndrome? 200919002726
campylobacter immunity and coinfection following a large outbreak in a farming community.an outbreak of campylobacteriosis affected approximately one-half of 165 people attending an annual farmers' dance in montrose, scotland, in november 2005. epidemiological investigations, including a cohort study (n = 164), identified chicken liver paté as the most likely vehicle of infection. paté preparation involved deliberate undercooking of chicken livers by flash-frying, followed by mechanical homogenization. typing of 32 campylobacter strains (isolated from submitted stools) by multilocus ...200919005146
campylobacter immunity and coinfection following a large outbreak in a farming community.an outbreak of campylobacteriosis affected approximately one-half of 165 people attending an annual farmers' dance in montrose, scotland, in november 2005. epidemiological investigations, including a cohort study (n = 164), identified chicken liver paté as the most likely vehicle of infection. paté preparation involved deliberate undercooking of chicken livers by flash-frying, followed by mechanical homogenization. typing of 32 campylobacter strains (isolated from submitted stools) by multilocus ...200919005146
rapid evolution and the importance of recombination to the gastroenteric pathogen campylobacter jejuni.responsible for the majority of bacterial gastroenteritis in the developed world, campylobacter jejuni is a pervasive pathogen of humans and animals, but its evolution is obscure. in this paper, we exploit contemporary genetic diversity and empirical evidence to piece together the evolutionary history of c. jejuni and quantify its evolutionary potential. our combined population genetics-phylogenetics approach reveals a surprising picture. campylobacter jejuni is a rapidly evolving species, subje ...200919008526
23s rrna gene mutations contributing to macrolide resistance in campylobacter jejuni and campylobacter coli.the genetic basis of macrolide resistance in campylobacter coli (n = 17) and c. jejuni (n = 35) isolates previously subjected to in vivo selective pressure was investigated to determine if the number of copies of 23s rrna genes with macrolide-associated mutations affects the minimum inhibitory concentration (mic) of macrolides. sequence data for domain v of the 23s rrna gene revealed that two macrolide-resistant c. coli isolates had adenine-->guanine transitions at position 2059 (a2059g, escheri ...200919014274
survival of campylobacter spp. in bovine faeces on pasture.to determine the survival on pasture of campylobacter spp. naturally present in bovine faeces and compare this with a previously published study using laboratory-cultured campylobacter spp.200919018956
antimicrobial susceptibility profiles and strain type diversity of campylobacter jejuni isolates from turkeys in eastern north carolina.campylobacter jejuni is one of the most common bacterial causes of human gastroenteritis, and recent findings suggest that turkeys are an important reservoir for this organism. in this study, 80 c. jejuni isolates from eastern north carolina were characterized for resistance to nine antimicrobials, and strain types were determined by fla typing, pulsed-field gel electrophoresis (pfge) with smai and kpni, and (for 41 isolates) multilocus sequence typing (mlst). pfge analysis suggested that many o ...200919028914
antimicrobial susceptibility profiles and strain type diversity of campylobacter jejuni isolates from turkeys in eastern north carolina.campylobacter jejuni is one of the most common bacterial causes of human gastroenteritis, and recent findings suggest that turkeys are an important reservoir for this organism. in this study, 80 c. jejuni isolates from eastern north carolina were characterized for resistance to nine antimicrobials, and strain types were determined by fla typing, pulsed-field gel electrophoresis (pfge) with smai and kpni, and (for 41 isolates) multilocus sequence typing (mlst). pfge analysis suggested that many o ...200919028914
quantifying transmission of campylobacter jejuni in commercial broiler flocks.since meat from poultry colonized with campylobacter spp. is a major cause of bacterial gastroenteritis, human exposure should be reduced by, among other things, prevention of colonization of broiler flocks. to obtain more insight into possible sources of introduction of campylobacter into broiler flocks, it is essential to estimate the moment that the first bird in a flock is colonized. if the rate of transmission within a flock were known, such an estimate could be determined from the change i ...200919047389
quantifying transmission of campylobacter jejuni in commercial broiler flocks.since meat from poultry colonized with campylobacter spp. is a major cause of bacterial gastroenteritis, human exposure should be reduced by, among other things, prevention of colonization of broiler flocks. to obtain more insight into possible sources of introduction of campylobacter into broiler flocks, it is essential to estimate the moment that the first bird in a flock is colonized. if the rate of transmission within a flock were known, such an estimate could be determined from the change i ...200919047389
risk factors for campylobacter jejuni and campylobacter coli in young cattle on english and welsh farms.campylobacter jejuni and c. coli are the most prevalent causes of bacterial diarrhoea in most of the western world. in great britain, the source remains unknown for the majority of cases, though poultry is considered the main source of infection. molecular typing methods identify cattle as a potential source of a proportion of the non-source-attributed cases, mainly through direct contact, environmental contamination or milk, but little is known about the epidemiology of campylobacter in cattle. ...200918835052
initial studies using aliphatic beta-nitro alcohols for therapeutic corneal cross-linking.corneal collagen cross-linking through uva-riboflavin photochemistry (uvar) has been shown to be an effective treatment for keratoconus and related keratectasias. in recent studies using sclera, the authors observed that short-chain aliphatic beta-nitro alcohols can cross-link collagenous tissue under physiologic conditions. thus, this study was undertaken to evaluate these agents as potential pharmacologic alternatives to uvar.200918836172
initial studies using aliphatic beta-nitro alcohols for therapeutic corneal cross-linking.corneal collagen cross-linking through uva-riboflavin photochemistry (uvar) has been shown to be an effective treatment for keratoconus and related keratectasias. in recent studies using sclera, the authors observed that short-chain aliphatic beta-nitro alcohols can cross-link collagenous tissue under physiologic conditions. thus, this study was undertaken to evaluate these agents as potential pharmacologic alternatives to uvar.200918836172
diversity and habitat specificity of free-living protozoa in commercial poultry houses.despite stringent biosecurity measures, infections by bacterial food pathogens such as campylobacter are a recurrent problem in industrial poultry houses. as the main transmission route remains unclear, persistence of these infections has been linked to bacterial survival and possibly multiplication within protozoan vectors. to date, however, virtually no information is available on the diversity and occurrence of free-living protozoa in these environments. using a combination of microscopic ana ...200919124593
structures of acrr and cmer: insight into the mechanisms of transcriptional repression and multi-drug recognition in the tetr family of regulators.the transcriptional regulators of the tetr family act as chemical sensors to monitor the cellular environment in many bacterial species. to perform this function, members of the tetr family harbor a diverse ligand-binding domain capable of recognizing the same series of compounds as the transporters they regulate. many of the regulators can be induced by a wide array of structurally unrelated compounds. binding of these structurally unrelated ligands to the regulator results in a conformational ...200919130905
structures of acrr and cmer: insight into the mechanisms of transcriptional repression and multi-drug recognition in the tetr family of regulators.the transcriptional regulators of the tetr family act as chemical sensors to monitor the cellular environment in many bacterial species. to perform this function, members of the tetr family harbor a diverse ligand-binding domain capable of recognizing the same series of compounds as the transporters they regulate. many of the regulators can be induced by a wide array of structurally unrelated compounds. binding of these structurally unrelated ligands to the regulator results in a conformational ...200919130905
comparison of loop-mediated isothermal amplification assay and conventional culture methods for detection of campylobacter jejuni and campylobacter coli in naturally contaminated chicken meat samples.we investigated the efficacy of a loop-mediated isothermal amplification (lamp) assay for detection of chicken meat samples naturally contaminated with campylobacter jejuni and campylobacter coli. a total of 144 preston enrichment broth cultures from chicken meat samples were assessed by using the lamp assay and conventional culture methods, which consist of a combination of preston enrichment culturing and plating onto butzler and modified charcoal cefoperazone deoxycholate agars. compared with ...200919139242
oxidative stress-induced peptidoglycan deacetylase in helicobacter pylori.structural modification of peptidoglycan (pg) is one of the mechanisms that pathogenic bacteria use to evade the host innate immune system. for the noninvasive human gastric pathogen helicobacter pylori, pg delivery to the host cells is one trigger of the immune response. h. pylori hp310 was markedly up-expressed upon cell exposure to oxidative stress. however, disruption of hp310 did not produce a phenotype distinguishable from the parent, including oxidative stress resistance characteristics. ...200919147492
roles of lipooligosaccharide and capsular polysaccharide in antimicrobial resistance and natural transformation of campylobacter jejuni.this study is aimed to determine the role of capsular polysaccharide (cps) and lipooligosaccharide (los) in modulating antimicrobial resistance and natural transformation of campylobacter jejuni, an important food-borne human pathogen.200919147521
recombineering reveals a diverse collection of ribosomal proteins l4 and l22 that confer resistance to macrolide antibiotics.mutations in ribosomal proteins l4 and l22 confer resistance to erythromycin and other macrolide antibiotics in a variety of bacteria. l4 and l22 have elongated loops whose tips converge in the peptide exit tunnel near the macrolide-binding site, and resistance mutations typically affect residues within these loops. here, we used bacteriophage lambda red-mediated recombination, or "recombineering," to uncover new l4 and l22 alleles that confer macrolide resistance in escherichia coli. we randomi ...200919150357
a dnase encoded by integrated element cjie1 inhibits natural transformation of campylobacter jejuni.the species campylobacter jejuni is considered naturally competent for dna uptake and displays strong genetic diversity. nevertheless, nonnaturally transformable strains and several relatively stable clonal lineages exist. in the present study, the molecular mechanism responsible for the nonnatural transformability of a subset of c. jejuni strains was investigated. comparative genome hybridization indicated that c. jejuni mu-like prophage integrated element 1 (cjie1) was more abundant in nonnatu ...200919151136
identification of novel carbohydrate modifications on campylobacter jejuni 11168 flagellin using metabolomics-based approaches.it is well known that the flagellin of campylobacter jejuni is extensively glycosylated by pseudaminic acid and the related acetamindino derivative, in addition to flagellin glycosylation being essential for motility and colonization of host cells. recently, the use of metabolomics permitted the unequivocal characterization of unique flagellin modifications in campylobacter, including novel legionaminic acid sugars in campylobacter coli, which had been impossible to ascertain in earlier studies ...200919154343
severe diarrhoea caused by highly ciprofloxacin-susceptible campylobacter isolates.the impact of fluoroquinolone resistance of campylobacter jejuni and campylobacter coli isolates on the outcome of the disease in sporadic campylobacter infections of finnish individuals was studied. questionnaires were sent, during a 6-month study period, to patients who were stool culture-positive for campylobacter spp. in total, 192 returned questionnaires were analysed and assessed, together with the susceptibility data of the respective bacterial isolates. only one (2%) of the domestic, but ...200919154485
campylobacter and arcobacter species sensitivity to commercial orange oil fractions.seven orange oil fractions were screened for their ability to inhibit the growth of selected campylobacter and arcobacter spp. using the standard agar-disk diffusion assay. cold pressed (cp) terpeneless valencia orange oil was found to be the most inhibitory to both campylobacter jejuni and campylobacter coli, exhibiting maximum zones of inhibition up to 80+/-0.0 mm. five-fold concentrated valencia oil and distilled d-limonene resulted in campylobacter inhibition zones ranging from 11.0+/-1.4 to ...200919070381
detection of escherichia coli, salmonella spp., shigella spp., yersinia enterocolitica, vibrio cholerae, and campylobacter spp. enteropathogens by 3-reaction multiplex polymerase chain reaction.the magnitude of bacterial diarrhea in developing countries is largely unknown because affordable detection methods are not available. we have developed a polymerase chain reaction (pcr)-based assay for use in areas with limited resources to screen for diarrheogenic strains from clinical isolates. to simplify the assay and minimize reagents, our method implemented the use of plasmids rather than bacteria as template controls and the use of bacterial suspensions or crude dna preparations rather t ...200918990527
detection of escherichia coli, salmonella spp., shigella spp., yersinia enterocolitica, vibrio cholerae, and campylobacter spp. enteropathogens by 3-reaction multiplex polymerase chain reaction.the magnitude of bacterial diarrhea in developing countries is largely unknown because affordable detection methods are not available. we have developed a polymerase chain reaction (pcr)-based assay for use in areas with limited resources to screen for diarrheogenic strains from clinical isolates. to simplify the assay and minimize reagents, our method implemented the use of plasmids rather than bacteria as template controls and the use of bacterial suspensions or crude dna preparations rather t ...200918990527
erythromycin resistance by l4/l22 mutations and resistance masking by drug efflux pump deficiency.we characterized the effects of classical erythromycin resistance mutations in ribosomal proteins l4 and l22 of the large ribosomal subunit on the kinetics of erythromycin binding. our data are consistent with a mechanism in which the macrolide erythromycin enters and exits the ribosome through the nascent peptide exit tunnel, and suggest that these mutations both impair passive transport through the tunnel and distort the erythromycin-binding site. the growth-inhibitory action of erythromycin w ...200919197244
inter- and intra-genomic heterogeneity of the intervening sequence in the 23s ribosomal rna gene of campylobacter jejuni and campylobacter coli.an intervening sequence (ivs) can be present or absent in the 23s rrna of campylobacter jejuni and campylobacter coli. as part of a survey, we used a polymerase chain reaction (pcr) assay to detect the presence of the ivs in 43 isolates of c. coli and 82 isolates of c. jejuni. an ivs was present in 40 (93.0%) of the c. coli and only 34 (41.5%) of the c. jejuni isolates. twelve (27.9%) of the c. coli isolates and seven (8.5%) of the c. jejuni isolates resulted in two polymerase chain reaction pro ...200919201124
prevalence of campylobacter jejuni and campylobacter coli in market-weight turkeys on-farm and at slaughter.to monitor the effects of feed withdrawal on the prevalence of campylobacter, market-weight turkeys from six farms were examined before and after perimarketing events (feed withdrawal, transport, and holding at the slaughterhouse). prior to transport, birds (n = 30 per farm) were slaughtered on-farm, and viscera (crops, duodenum, jejunum, ileum, colon, ceca, gallbladder, and spleen) were removed on the premises. within ca. 48 h, cohorts (n = 30 per farm) from the same flock were transported to a ...200919205462
genetic diversity of campylobacter on broiler carcasses collected preevisceration and postchill in 17 u.s. poultry processing plants.campylobacter jejuni and campylobacter coli are the most important human enteropathogens among the campylobacters. the objective of this study was to determine how diversity in campylobacter populations found on chicken carcasses collected from 17 broiler processing plants in the united states is impacted by processing. genetic diversity was determined for up to four isolates per carcass by sequencing the short variable region (svr) of the flaa locus. on 70% of campylobacter-positive carcasses, ...200919205463
genotyping of campylobacter coli isolated from humans and retail meats using multilocus sequence typing and pulsed-field gel electrophoresis.to determine the antimicrobial resistant profiles and clonality of campylobacter coli isolated from clinically ill humans and retail meats.200919226383
a pan-european survey of antimicrobial susceptibility towards human-use antimicrobial drugs among zoonotic and commensal enteric bacteria isolated from healthy food-producing animals.the aim of the study was to study antimicrobial susceptibility in escherichia coli, salmonella, campylobacter and enterococcus recovered from chickens, pigs and cattle using uniform methodology.200919233897
antiganglioside antibodies and their pathophysiological effects on guillain-barré syndrome and related disorders--a review.guillain-barré syndrome (gbs) is an acute immune-mediated polyradiculoneuropathy which can cause acute quadriplegia. infection with micro-organisms, including campylobacter jejuni (c. jejuni), haemophilus influenzae, and cytomegalovirus (cmv), is recognized as a main triggering event for the disease. lipooligosaccharide (los) genes are responsible for the formation of human ganglioside-like los structures in infectious micro-organisms that can induce gbs. molecular mimicry of loss on the surface ...200919240270
evaluation of procedures for outer membrane isolation from campylobacter jejuni.although infection with campylobacter jejuni is one of the leading causes of gastroenteritis worldwide, relatively little is known about the factors that are required to elicit a protective immune response. the need for a vaccine against this pathogen is well recognized and a number of vaccine candidates have been tested with varying degrees of success; however, there is still a lack of a suitable vaccine. to gain a better understanding of the outer-membrane protein components of this organism, ...200919246768
antibiotic resistance in campylobacter: emergence, transmission and persistence.campylobacter is a leading foodborne bacterial pathogen, which causes gastroenteritis in humans. this pathogenic organism is increasingly resistant to antibiotics, especially fluoroquinolones and macrolides, which are the most frequently used antimicrobials for the treatment of campylobacteriosis when clinical therapy is warranted. as a zoonotic pathogen, campylobacter has a broad animal reservoir and infects humans via contaminated food, water or milk. antibiotic usage in both animal agricultur ...200919257846
attribution of campylobacter infections in northeast scotland to specific sources by use of multilocus sequence typing.we show that a higher incidence of campylobacteriosis is found in young children (age, <5 years) living in rural, compared with urban, areas. association of this difference with particular animal sources was evaluated using multilocus sequence typing. this evaluation was achieved by comparing campylobacter isolates originating from these children, retail poultry, and a range of animal sources by use of source attribution and phylogenetic analysis methods. the results indicate that chicken is a m ...200919265482
campylobacter genotypes from food animals, environmental sources and clinical disease in scotland 2005/6.a nationwide multi-locus sequence typing (mlst) survey was implemented to analyze patterns of host association among campylobacter jejuni and campylobacter coli isolates from clinical disease in scotland (july 2005-september 2006), food animals (chickens, cattle, sheep, pigs and turkey), non-food animals (wild birds) and the environment. sequence types (sts) were determined for 5247 clinical isolates and 999 from potential disease sources (augmented with 2420 published sts). certain sts were ove ...200919269051
campylobacter genotyping to determine the source of human infection.campylobacter species cause a high proportion of bacterial gastroenteritis cases and are a significant burden on health care systems and economies worldwide; however, the relative contributions of the various possible sources of infection in humans are unclear.200919275496
the cmp-legionaminic acid pathway in campylobacter: biosynthesis involving novel gdp-linked precursors.the sialic acid-like sugar 5,7-diacetamido-3,5,7,9-tetradeoxy-d-glycero-d-galacto-nonulosonic acid, or legion-aminic acid, is found as a virulence-associated cell-surface glycoconjugate in the gram-negative bacteria legionella pneumophila and campylobacter coli. l. pneumophila serogroup 1 strains, causative agents of legionnaire's disease, contain an alpha2,4-linked homopolymer of legionaminic acid within their lipopolysaccharide o-chains, whereas the gastrointestinal pathogen c. coli modifies i ...200919282391
molecular epidemiology and characterization of campylobacter spp. isolated from wild bird populations in northern england.campylobacter infections have been reported at prevalences ranging from 2 to 50% in a range of wild bird species, although there have been few studies that have investigated the molecular epidemiology of campylobacter spp. consequently, whether wild birds are a source of infection in humans or domestic livestock or are mainly recipients of domestic animal strains and whether separate cycles of infection occur remain unknown. to address these questions, serial cross-sectional surveys of wild bird ...200919286781
regulation of superoxide dismutase (sod) genes by sara in staphylococcus aureus.the scavenging of reactive oxygen species (ros) within cells is regulated by several interacting factors, including transcriptional regulators. involvement of sara family genes in the regulation of proteins involved in the scavenging of ros is largely unknown. in this report, we show that under aerobic conditions, the levels of sodm and soda transcription, in particular the sodm transcript, are markedly enhanced in the sara mutant among the tested sara family mutants. increased levels of sod exp ...200919286803
independent evolution of neurotoxin and flagellar genetic loci in proteolytic clostridium botulinum.proteolytic clostridium botulinum is the causative agent of botulism, a severe neuroparalytic illness. given the severity of botulism, surprisingly little is known of the population structure, biology, phylogeny or evolution of c. botulinum. the recent determination of the genome sequence of c. botulinum has allowed comparative genomic indexing using a dna microarray.200919298644
campylobacter jejuni glycosylation island important in cell charge, legionaminic acid biosynthesis, and colonization of chickens.previously, we identified five genes (cj1321 to cj1326, of which cj1325 and cj1326 are a single gene) in the o-linked flagellin glycosylation island that are highly prevalent in campylobacter jejuni isolates from chickens. we report mutagenesis, functional, and structural data to confirm that this locus, and cj1324 in particular, has a significant contributory role in the colonization of chickens by c. jejuni. a motile deltacj1324 mutant with intact flagella was considerably less hydrophobic and ...200919307210
incidence and risk factors for community-acquired acute gastroenteritis in north-west germany in 2004.in developed countries, acute gastroenteritis (age) is a major source of morbidity. however, only a few studies have estimated its incidence and the associated medical burden. this population-based study determined the incidence of community-acquired age patients seeking medical care and the relative role of various pathogens. stool samples from patients with age presenting to a general practitioner (gp), pediatrician, or specialist in internal medicine for that reason were screened for various ...200919319582
survival at refrigeration and freezing temperatures of campylobacter coli and campylobacter jejuni on chicken skin applied as axenic and mixed inoculums.campylobacter is considered to be the most common cause of bacterial diarrhoeal illness in the developed world. many cases are thought to be acquired from consumption of undercooked poultry. the aim of this study was to compare the effect of the rate of cooling on the survival, at 4 degrees c and -20 degrees c, of campylobacter coli and campylobacter jejuni strains, inoculated on chicken skin from axenic culture or as mixed inoculums. strains chilled in a domestic refrigerator varied in their to ...200919324444
temporal patterns and risk factors for escherichia coli o157 and campylobacter spp, in young cattle.escherichia coli o157 and campylobacter jejuni and campylobacter coli are zoonotic pathogens originating from farm animals. cattle are the main reservoir for e. coli o157 and also contribute to human cases of campylobacteriosis through contaminated milk, direct contact, and environmental contamination. thirty groups of young cattle on 30 farms were observed for 7 months and sampled on 4 to 6 separate occasions for e. coli o157 and c. jejuni/coli to characterize shedding patterns and identify ris ...200919343935
comparative studies of campylobacter jejuni genomic diversity reveal the importance of core and dispensable genes in the biology of this enigmatic food-borne pathogen.mlst, dna microarrays, and genome sequencing has allowed for a greater understanding of the metabolic capacity and epidemiology of campylobacter jejuni. while strain-specific genes may provide an isolate a selective advantage in environments and contribute to the organism's pathogenicity, recent work indicates that c. jejuni pathogenicity is dictated by variations in the nucleotide sequence of core genes. challenges facing c. jejuni researchers include determining (a) the degree to which genomic ...200919346123
campylobacter colonization of the turkey intestine in the context of microbial community development.patterns of microbial community dynamics in the turkey intestine were examined. every week of the 18-week production cycle, cecal bacterial communities and campylobacter loads were examined from five birds for each of two flocks. molecular fingerprinting via the automated ribosomal intergenic spacer analysis (arisa) and terminal restriction fragment length polymorphism (t-rflp) of the cecal samples revealed that microbial communities changed in a time-dependent manner, and during both trials the ...200919346343
a longitudinal study of campylobacter distribution in a turkey production chain.campylobacter is the most common cause of bacterial enteritis worldwide. handling and eating of contaminated poultry meat has considered as one of the risk factors for human campylobacteriosis. campylobacter contamination can occur at all stages of a poultry production cycle. the objective of this study was to determine the occurrence of campylobacter during a complete turkey production cycle which lasts for 1,5 years of time. for detection of campylobacter, a conventional culture method was com ...200919348687
functional characterization of excision repair and reca-dependent recombinational dna repair in campylobacter jejuni.the presence and functionality of dna repair mechanisms in campylobacter jejuni are largely unknown. in silico analysis of the complete translated genome of c. jejuni nctc 11168 suggests the presence of genes involved in methyl-directed mismatch repair (mmr), nucleotide excision repair, base excision repair (ber), and recombinational repair. to assess the functionality of these putative repair mechanisms in c. jejuni, muts, uvrb, ung, and reca knockout mutants were constructed and analyzed for t ...200919376866
high-throughput identification of bacteria and yeast by matrix-assisted laser desorption ionization-time of flight mass spectrometry in conventional medical microbiology laboratories.matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) is suitable for high-throughput and rapid diagnostics at low costs and can be considered an alternative for conventional biochemical and molecular identification systems in a conventional microbiological laboratory. first, we evaluated maldi-tof ms using 327 clinical isolates previously cultured from patient materials and identified by conventional techniques (vitek-ii, api, and biochemical tests). discre ...201020053859
amoebae and algae can prolong the survival of campylobacter species in co-culture.several species of free-living amoebae can cause disease in humans. however, in addition to the direct pathogenicity of e.g. acanthamoebae and naegleria species, they are recognized as environmental hosts, indirectly involved in the epidemiology of many pathogenic bacteria. although several studies have demonstrated intracellular survival of many different bacteria in these species, the extent of such interactions as well as the implications for the epidemiology of the bacterial species involved ...201020056117
comparison of campylobacter populations isolated from a free-range broiler flock before and after slaughter.relatively little is known about the campylobacter genotypes colonizing extensively reared broiler flocks and their survival through the slaughter process, despite the increasing demand for free-range and organic products by the consumer. campylobacter isolates from a free-range boiler flock, sampled before and after slaughter, were genotyped by mlst (multilocus sequence typing) and sequence analysis of the flaa short variable region (svr). the campylobacter genotypes isolated before and after s ...201020071049
understanding the molecular epidemiology of the footrot pathogen dichelobacter nodosus to support control and eradication programs.the gram-negative anaerobe dichelobacter nodosus is the primary etiologic agent of ovine footrot. few studies of the genetic diversity and epidemiology of d. nodosus have been done, despite the economic cost and welfare implications of the disease. this study examined a large collection of australian isolates; 735 isolates from footrot-infected sheep from 247 farms in western australia (wa) were tested by pulsed-field gel electrophoresis (pfge), and a subset of 616 isolates was tested by infrequ ...201020071558
understanding the molecular epidemiology of the footrot pathogen dichelobacter nodosus to support control and eradication programs.the gram-negative anaerobe dichelobacter nodosus is the primary etiologic agent of ovine footrot. few studies of the genetic diversity and epidemiology of d. nodosus have been done, despite the economic cost and welfare implications of the disease. this study examined a large collection of australian isolates; 735 isolates from footrot-infected sheep from 247 farms in western australia (wa) were tested by pulsed-field gel electrophoresis (pfge), and a subset of 616 isolates was tested by infrequ ...201020071558
expanded multilocus sequence typing and comparative genomic hybridization of campylobacter coli isolates from multiple hosts.the purpose of this work was to evaluate the evolutionary history of campylobacter coli isolates derived from multiple host sources and to use microarray comparative genomic hybridization to assess whether there are particular genes comprising the dispensable portion of the genome that are more commonly associated with certain host species. genotyping and clonalframe analyses of an expanded 16-gene multilocus sequence typing (mlst) data set involving 85 isolates from 4 different hosts species te ...201020097815
species-specific identification and differentiation of arcobacter, helicobacter and campylobacter by full-spectral matrix-associated laser desorption/ionization time of flight mass spectrometry analysis.rapid and reliable identification of arcobacter and helicobacter species, and their distinction from phenotypically similar campylobacter species, has become increasingly important, since many of them are now recognized as human and/or animal pathogens. matrix-associated laser desorption/ionization-time of flight (maldi-tof) ms has been shown to be a rapid and sensitive method for characterization of micro-organisms. in this study, we therefore established a reference database of selected arcoba ...201019959629
study of cytolethal distending toxin (cdt) in campylobacter coli using a multiplex polymerase chain reaction assay and its distribution among clinical and food strains.from a collection of 242 food isolates of campylobacter spp. 72 were identified as campylobacter jejuni and 170 as campylobacter coli and of 112 isolates from clinical sources, 92 were identified as c. jejuni and 20 as c. coli. the results for food isolates were in contrast to other reported identifications. twenty c. coli strains from clinical cases of campylobacter that occurred in portugal and 170 isolated from poultry products were examined for the presence of cytolethal distending toxin (cd ...201019821742
development and evaluation of internal amplification controls for use in a real-time duplex pcr assay for detection of campylobacter coli and campylobacter jejuni.a common problem of both conventional and real-time pcr assays is failure of dna amplification due to the presence of inhibitory substances in samples. in view of this, our aim was to develop and evaluate internal amplification controls (iacs) for use with an existing duplex real-time pcr assay for campylobacter coli and campylobacter jejuni. both competitive and non-competitive iacs were developed and evaluated. the competitive approach involved a dna fragment of the coding region of the fish v ...201019833779
prolonged survival of campylobacter species in bovine manure compost.the persistence of naturally occurring campylobacteria in aerobic compost constructed of manure from beef cattle that were administered chlortetracycline and sulfamethazine (as700) or from cattle not administered antibiotics (control) was examined. although there were no differences in population sizes of heterotrophic bacteria, the temperature of as700 compost was more variable and did not become as high as that of control compost. there were significant differences in water content, total carb ...201020023098
comparison of pcr binary typing (p-bit), a new approach to epidemiological subtyping of campylobacter jejuni, with serotyping, pulsed-field gel electrophoresis, and multilocus sequence typing methods.to overcome some of the deficiencies with current molecular typing schema for campylobacter spp., we developed a prototype pcr binary typing (p-bit) approach. we investigated the distribution of 68 gene targets in 58 campylobacter jejuni strains, one campylobacter lari strain, and two campylobacter coli strains for this purpose. gene targets were selected on the basis of distribution in multiple genomes or plasmids, and known or putative status as an epidemicity factor. strains were examined wit ...201020023103
activation of human and chicken toll-like receptors by campylobacter spp.campylobacter infection in humans is accompanied by severe inflammation of the intestinal mucosa, in contrast to colonization of chicken. the basis for the differential host response is unknown. toll-like receptors (tlrs) sense and respond to microbes in the body and participate in the induction of an inflammatory response. thus far, the interaction of campylobacter with chicken tlrs has not been studied. here, we investigated the potential of four campylobacter strains to activate human tlr1/2/ ...201020038539
activation of human and chicken toll-like receptors by campylobacter spp.campylobacter infection in humans is accompanied by severe inflammation of the intestinal mucosa, in contrast to colonization of chicken. the basis for the differential host response is unknown. toll-like receptors (tlrs) sense and respond to microbes in the body and participate in the induction of an inflammatory response. thus far, the interaction of campylobacter with chicken tlrs has not been studied. here, we investigated the potential of four campylobacter strains to activate human tlr1/2/ ...201020038539
antimicrobial susceptibilities of multidrug-resistant campylobacter jejuni and c. coli strains: in vitro activities of 20 antimicrobial agents.there is a paucity of information regarding antimicrobial agents that are suitable to treat severe infections caused by multidrug-resistant campylobacter spp. our aim was to identify agents that are potentially effective against multiresistant campylobacter strains. the in vitro activities of 20 antimicrobial agents against 238 campylobacter strains were analyzed by determining mics by the agar plate dilution method or the etest. these strains were selected from 1,808 campylobacter isolates coll ...201020038624
development of a dna microarray to detect antimicrobial resistance genes identified in the national center for biotechnology information database.to understand the mechanisms and epidemiology of antimicrobial resistance (ar), the genetic elements responsible must be identified. due to the myriad of possible genes, a high-density genotyping technique is needed for initial screening. to achieve this, ar genes in the national center for biotechnology information genbank database were identified by their annotations and compiled into a nonredundant list of 775 genes. a dna microarray was constructed of 70mer oligonucelotide probes designed to ...201019916789
recrudescent campylobacter jejuni infection in an immunocompetent adult following experimental infection with a well-characterized organism.the recrudescence of infection with campylobacter jejuni after appropriate antibiotic treatment has not been previously reported in an immunocompetent adult. we present the complete clinical, microbiologic, and immunologic evaluation of a closely monitored healthy male with recrudescent c. jejuni infection occurring in the absence of immunodeficiency following experimental infection with a well-characterized strain. after antibiotic treatment, the initial infection was clinically cleared and mic ...201019923572
recrudescent campylobacter jejuni infection in an immunocompetent adult following experimental infection with a well-characterized organism.the recrudescence of infection with campylobacter jejuni after appropriate antibiotic treatment has not been previously reported in an immunocompetent adult. we present the complete clinical, microbiologic, and immunologic evaluation of a closely monitored healthy male with recrudescent c. jejuni infection occurring in the absence of immunodeficiency following experimental infection with a well-characterized strain. after antibiotic treatment, the initial infection was clinically cleared and mic ...201019923572
campylobacter jejuni and campylobacter coli genotyping by high-resolution melting analysis of a flaa fragment.the highly variable flagellin-encoding flaa gene has long been used for genotyping campylobacter jejuni and campylobacter coli. high-resolution melting (hrm) analysis is emerging as an efficient and robust method for discriminating dna sequence variants. the objective of this study was to apply hrm analysis to flaa-based genotyping. the initial aim was to identify a suitable flaa fragment. it was found that the pcr primers commonly used to amplify the flaa short variable repeat (svr) yielded a m ...201019933351
investigation of food and environmental exposures relating to the epidemiology of campylobacter coli in humans in northwest england.this study uses multilocus sequence typing (mlst) to investigate the epidemiology of campylobacter coli in a continuous study of a population in northwest england. all cases of campylobacter identified in four local authorities (government administrative boundaries) between 2003 and 2006 were identified to species level and then typed, using mlst. epidemiological information was collected for each of these cases, including food and recreational exposure variables, and the epidemiologies of c. je ...201019854914
a genomic island defines subspecies-specific virulence features of the host-adapted pathogen campylobacter fetus subsp. venerealis.the pathogen campylobacter fetus comprises two subspecies, c. fetus subsp. fetus and c. fetus subsp. venerealis. although these taxa are highly related on the genome level, they are adapted to distinct hosts and tissues. c. fetus subsp. fetus infects a diversity of hosts, including humans, and colonizes the gastrointestinal tract. in contrast, c. fetus subsp. venerealis is largely restricted to the bovine genital tract, causing epidemic abortion in these animals. in light of their close genetic ...201019897645
a genomic island defines subspecies-specific virulence features of the host-adapted pathogen campylobacter fetus subsp. venerealis.the pathogen campylobacter fetus comprises two subspecies, c. fetus subsp. fetus and c. fetus subsp. venerealis. although these taxa are highly related on the genome level, they are adapted to distinct hosts and tissues. c. fetus subsp. fetus infects a diversity of hosts, including humans, and colonizes the gastrointestinal tract. in contrast, c. fetus subsp. venerealis is largely restricted to the bovine genital tract, causing epidemic abortion in these animals. in light of their close genetic ...201019897645
comparison between the biofilm initiation of campylobacter jejuni and campylobacter coli strains to an inert surface using biofilm ring test.the adhesion to an inert surface (the first step of biofilm formation) of the two main pathogenic campylobacter species, campylobacter jejuni and campylobacter coli, isolated from diverse origins, was compared.201019796124
dna identification and characterization of campylobacter jejuni and campylobacter coli isolated from caecal samples of chickens in grenada.to speciate campylobacter strains from the caeca of chickens in grenada using pcr and to evaluate dna-based typing methods for the characterization of these isolates.201019735321
diversity of campylobacter jejuni and campylobacter coli genotypes from human and animal sources from rio de janeiro, brazil.to compare the genotypes of campylobacter jejuni and campylobacter coli isolates of human and animal origin collected in rio de janeiro city, 30 c. jejuni and 35 c. coli isolates from animal sources (n=45) and human patients with gastroenteritis (n=20) were genotyped by pcr-based techniques, namely random amplified polymorphic dna (rapd-pcr) and enterobacterial repetitive intergenic consensus sequence (eric-pcr). rapd-pcr identified 50 types and eric-pcr identified 22 genotypes, among the 65 cam ...201019765787
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