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comparative phylogenomics of the food-borne pathogen campylobacter jejuni reveals genetic markers predictive of infection source.campylobacter jejuni is the predominant cause of bacterial gastroenteritis worldwide, but traditional typing methods are unable to discriminate strains from different sources that cause disease in humans. we report the use of genomotyping (whole-genome comparisons of microbes using dna microarrays) combined with bayesian-based algorithms to model the phylogeny of this major food-borne pathogen. in this study 111 c. jejuni strains were examined by genomotyping isolates from humans with a spectrum ...200516230626
the heterogeneity of campylobacter jejuni and campylobacter coli strains isolated from healthy cattle.to identify campylobacters isolated from clinically healthy cattle at species level by a multiplex polymerase chain reaction (m-pcr). the heterogeneity among campylobacter jejuni and campylobacter coli isolates was also investigated by using a restriction fragment length polymorphism (rflp) analysis of flagellin (flaa) gene.200516238642
dissimilatory metabolism of nitrogen oxides in bacteria: comparative reconstruction of transcriptional networks.bacterial response to nitric oxide (no) is of major importance since no is an obligatory intermediate of the nitrogen cycle. transcriptional regulation of the dissimilatory nitric oxides metabolism in bacteria is diverse and involves fnr-like transcription factors hcpr, dnr, and nnrr; two-component systems narxl and narqp; no-responsive activator norr; and nitrite-sensitive repressor nsrr. using comparative genomics approaches, we predict dna-binding motifs for these transcriptional factors and ...200516261196
campylobacter coli in swine production: antimicrobial resistance mechanisms and molecular epidemiology.the aim of this study was to determine antimicrobial resistance, to evaluate and compare the use of two genotyping methods for molecular epidemiology purposes, and to determine the genotypic diversity of campylobacter coli of porcine origin. a total of 100 c. coli isolates from swine were tested for susceptibility to six antimicrobials using the agar dilution method and genotyped using two high-resolution fingerprinting approaches: multilocus sequence typing (mlst) and pulsed-field gel electroph ...200516272508
microbial health risk posed by table eggs in trinidad.a survey of the microbial quality of table eggs sold in trinidad was conducted. for 23 poultry layer farms each visited twice approximately 1 month apart, 25 pooled eggs constituted a composite sample, for 14 shopping malls each visited twice approximately 1 month apart, six pooled eggs made a composite sample and for a total of 102 other retailers across the country each visited once over a 4-month period, six pooled eggs constituted a composite sample. swabs of egg shells and egg content were ...200516274501
the importance of campylobacter coli in human campylobacteriosis: prevalence and genetic characterization.the primary aim of this study was to detect and genotype campylobacter coli strains from humans over a period of one year from november 2002 to october 2003. campylobacter spp. were isolated from patients with symptoms of enteric infection. amplified fragment length polymorphism (aflp) analysis was used to identify the genetic diversity of c. coli strains by cluster analysis. a total of 18.6% of all campylobacter isolates were identified as c. coli. these data show, that c. coli is indeed of imp ...200516274505
identification of a new family of enzymes with potential o-acetylpeptidoglycan esterase activity in both gram-positive and gram-negative bacteria.the metabolism of the rigid bacterial cell wall heteropolymer peptidoglycan is a dynamic process requiring continuous biosynthesis and maintenance involving the coordination of both lytic and synthetic enzymes. the o-acetylation of peptidoglycan has been proposed to provide one level of control on these activities as this modification inhibits the action of the major endogenous lytic enzymes, the lytic transglycosylases. the o-acetylation of peptidoglycan also inhibits the activity of the lysozy ...200516111493
does age acquired immunity confer selective protection to common serotypes of campylobacter jejuni?campylobacter infection is a major cause of bacterial gastrointestinal disease. exposure to campylobacter is known to produce an immune response in humans that can prevent future symptomatic infections. further, studies of the general population have shown that seroprevalence to campylobacter increases with age.200516117832
effect of preslaughter events on prevalence of campylobacter jejuni and campylobacter coli in market-weight turkeys.the effects of events which occur prior to slaughter, such as loading, transport, and holding at an abattoir, on the prevalence of campylobacter species, including campylobacter jejuni and campylobacter coli, were examined. cloacal swabs from market-weight turkeys in each of five flocks were obtained on a farm prior to loading (time 1; 120 swabs per flock) and after transport and holding at the abattoir (time 2; 120 swabs per flock). a statistically significant increase in the overall prevalence ...200515932973
genetic diversity and antibiotic resistance patterns in a campylobacter population isolated from poultry farms in switzerland.the diversity and genetic interrelation of campylobacter jejuni and c. coli isolated from swiss poultry were assessed by three independent typing methods. samples were derived prior to slaughter from 100 randomly selected flocks (five birds per flock) raised on three different farm types. the observed flock prevalence was 54% in total, with 50% for conventional and 69% for free-range farms. birds held on farms with a confined roaming area had the lowest prevalence of 37%. campylobacter isolates ...200515932975
prevalence of potential virulence markers in polish campylobacter jejuni and campylobacter coli isolates obtained from hospitalized children and from chicken carcasses.the pathogenicity of thermotolerant campylobacter species, common food-borne pathogens, depends on certain factors unevenly distributed among strains of different origin. the prevalence of such markers has never been examined in a population of polish campylobacter strains of human and poultry origin. therefore, we analysed the presence of the cadf, cdta, cdtb and cdtc genes and the iam sequence in campylobacter jejuni (n = 115) and campylobacter coli (n = 57) isolates from children with diarrho ...200515947425
discrimination of enterobacterial repetitive intergenic consensus pcr types of campylobacter coli and campylobacter jejuni by fourier transform infrared spectroscopy.fourier transform infrared spectroscopy (ft-ir) has been used together with pattern recognition methodology to study isolates belonging to the species campylobacter coli and campylobacter jejuni and to compare ft-ir typing schemes with established genomic profiles based on enterobacterial repetitive intergenic consensus pcr (eric-pcr). seventeen isolates were cultivated under standardized conditions for 2, 3, and 4 days to study variability and improve reproducibility. eric-pcr profiles and ft-i ...200516085819
news and notes: an atypical campylobacter coli exhibiting unusual morphology.campylobacter coli cells are characterized by a comma, or spiral shape, and a single polar flagellum. here we report stable spontaneous changes in morphology to an aflagellated straight rod. the ability to colonize the chick cecum was lost. the atypical cells were compared with the original c. coli 67 culture from which they were derived, with pcr, riboprinting, and pfge.200516091850
prevalence and antimicrobial resistance of campylobacter in antimicrobial-free and conventional pig production systems.the objectives of this study were to determine and compare the prevalence and antimicrobial resistance of campylobacter species in swine reared in conventional and antimicrobial-free (abf) production systems. campylobacter coli was the predominant species, with 1,459 isolates (99%) in the study. we found significantly higher prevalence of c. coli on the abf farms (77.3%) than on the conventional farms (27.6%) among pigs at the nursery stage (p < 0.001). at slaughter, we found significantly highe ...200516300080
identification and characterization of neub3 from campylobacter jejuni as a pseudaminic acid synthase.campylobacter jejuni and campylobacter coli are the main causes of bacterial diarrhea worldwide, and helicobacter pylori is known to cause duodenal ulcers. in all of these pathogenic organisms, the flagellin proteins are heavily glycosylated with a 2-keto-3-deoxy acid, pseudaminic acid (5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-l-manno-nonulosonic acid). the presence of pseudaminic acid is required for the proper development of the flagella and is thereby necessary for motility in, and invasi ...200516120604
campylobacter coli: prevalence and antimicrobial resistance in antimicrobial-free (abf) swine production systems.to determine the prevalence and antimicrobial resistance of campylobacter species in swine reared in the intensive and extensive antimicrobial-free (abf) production systems at farm and slaughter. in the abf system, antimicrobials are neither used for growth promotion nor therapeutic purposes.200516120624
involvement of the cmeabc efflux pump in the macrolide resistance of campylobacter coli.this study was conducted to examine the role of the cmeabc efflux pump in decreasing the susceptibility of campylobacter coli to macrolides and ketolides in the context of absence or presence of mutations in the 23s rrna genes.200516157618
factors affecting the pressure resistance of some campylobacter species.to compare pressure resistance between strains of campylobacter jejuni, campylobacter coli, campylobacter lari and campylobacter fetus, and to investigate the effect of suspending medium on pressure resistance of sensitive and more resistant strains.200516162138
mortality following campylobacter infection: a registry-based linkage study.campylobacteriosis is one of the most commonly identified causes of bacterial diarrheal disease and a common cause of gastroenteritis in travellers from developed nations. despite the widespread occurrence, there is little information on campylobacter mortality.200516162289
acid-induced activation of the urease promoters is mediated directly by the arsrs two-component system of helicobacter pylori.the nickel-containing enzyme urease is an essential colonization factor of the human gastric pathogen helicobacter pylori which enables the bacteria to survive the low-ph conditions of the stomach. transcription of the urease genes is positively controlled in response to increasing concentrations of nickel ions and acidic ph. here we demonstrate that acid-induced transcription of the urease genes is mediated directly by the arsrs two-component system. footprint analyses identify binding sites of ...200516177315
multiplex pcr for identification of campylobacter coli and campylobacter jejuni from pure cultures and directly on stool samples.a multiplex-pcr method, specifically designed for application in routine diagnostic laboratories, was developed for the detection of campylobacter coli and campylobacter jejuni. primers were directed towards the following loci: the hippuricase gene (hipo) characteristic of c. jejuni, a sequence partly covering an aspartokinase gene characteristic of c. coli, and a universal 16s rdna gene sequence serving as an internal positive control for the pcr. the method was tested on 47 c. coli strains and ...200516192435
campylobacter in food animals and humans in northern thailand.cross-sectional, longitudinal, and case-control studies were conducted to describe the epidemiology of campylobacter in chickens, swine, dairy cows, farm workers, nonfarm residents, and children with diarrhea. samples were collected in chiang mai and lamphung provinces of northern thailand from 2000 through 2003. a total of 2,360 samples were processed. results from the cross-sectional study indicated that the prevalences of campylobacter in chickens at the farm, slaughterhouse, and market were ...200516355821
characterization of a cmeabc operon in a quinolone-resistant campylobacter coli isolate of irish origin.in this study, a tripartite-operon-encoding efflux system together with its regulatory gene was characterized in an irish campylobacter coli isolate cit-382 showing high-level resistance to nalidixic acid and ciprofloxacin. sequence comparisons revealed significant homology between c. coli and the cmeabc operon of campylobacter jejuni. conservation of functional sequence domains and motifs were noted among c. coli and similar operons in unrelated organisms. a transcriptional regulatory gene cmer ...200516359189
neither hippurate-negative brachyspira pilosicoli nor brachyspira pilosicoli type strain caused diarrhoea in early-weaned pigs by experimental infection.a hippurate-negative biovariant of brachyspira pilosicoli (b. pilosicolihipp-) is occasionally isolated in diarrhoeic pigs in finland, often concomitantly with hippurate-positive b. pilosicoli or lawsonia intracellularis. we studied pathogenicity of b. pilosicolihipp- with special attention paid to avoiding co-infection with other enteric pathogens. pigs were weaned and moved to barrier facilities at the age of 11 days. at 46 days, 8 pigs were inoculated with b. pilosicolihipp- strain br1622, 8 ...200516398337
extended multilocus sequence typing system for campylobacter coli, c. lari, c. upsaliensis, and c. helveticus.a multilocus sequence typing (mlst) system has been reported previously for campylobacter jejuni to both differentiate strains and identify clonal lineages. however, sequence variation at the mlst loci prevents its use for closely related campylobacter species. we describe herein an expanded mlst method to include three clinically relevant campylobacter species, c. coli, c. lari, and c. upsaliensis, and a fourth campylobacter species, c. helveticus. the c. coli and c. helveticus methods use the ...200515872261
evaluation of agar plates for direct enumeration of campylobacter spp. from poultry carcass rinses.campy-cefex, a modification of campy-cefex, modified charcoal cefoperazone deoxycholate (mccda), karmali, campy, and campy-line agars were evaluated for their efficiency to isolate and enumerate campylobacter spp. from poultry carcass rinses. campy-cefex and its modification produced the best results but were statistically similar to campy, mccda, and karmali.200515933040
fly transmission of campylobacter.an annual increase in campylobacter infection in england and wales begins in may and reaches a maximum in early june. this increase occurs in all age groups and is seen in all geographic areas. examination of risk factors that might explain this seasonal increase identifies flies as a potential source of infection. the observed pattern of infection is hypothesized to reflect an annual epidemic caused by direct or indirect contamination of people by small quantities of infected material carried b ...200515757548
prevalence and genetic diversity of campylobacter spp. in environmental water samples from a 100-square-kilometer predominantly dairy farming area.water samples were taken systematically from a 100-km2 area of mainly dairy farmland in northwestern england and examined for campylobacter spp. pulsed-field gel electrophoresis-restriction fragment length polymorphism (pfge-rflp) and flaa strain typing of campylobacter jejuni and campylobacter coli isolates were done. data on the water source and the adjacent environment were recorded and examined as explanatory variables. campylobacter spp. were isolated from 40.5% (n = 119) of the water sampl ...200515812015
measurement of the viability of lawsonia intracellularis.the objective of this study was to develop and test both a flow cytometry method (fcm) and a direct count method (dcm) that both use fluorescent stains to determine the viability of lawsonia intracellularis (li), an obligate intracellular bacterium and the cause of proliferative enteropathy (pe) in pigs and other animal species. live li were passaged in cell culture and harvested from infected mccoy cells. dead li were prepared by exposing live li to 70% isopropyl alcohol for 30 min. seven sampl ...200516479724
activities of telithromycin, erythromycin, fluoroquinolones, and doxycycline against campylobacter strains isolated from finnish subjects.the in vitro susceptibilities of 478 campylobacter jejuni and campylobacter coli strains isolated from finnish subjects during 2002 to 2004 were determined. susceptibility to erythromycin remained high, and telithromycin did not offer any advantage over erythromycin. reduced susceptibilities to fluoroquinolones and doxycycline were detected almost exclusively among isolates of foreign origin.200616495275
comparison of culture and a novel 5' taq nuclease assay for direct detection of campylobacter fetus subsp. venerealis in clinical specimens from cattle.a campylobacter fetus subsp. venerealis-specific 5' taq nuclease pcr assay using a 3' minor groove binder-dna probe (taqman mgb) was developed based on a subspecies-specific fragment of unknown identity (s. hum, k. quinn, j. brunner, and s. l. on, aust. vet. j. 75:827-831, 1997). the assay specifically detected four c. fetus subsp. venerealis strains with no observed cross-reaction with c. fetus subsp. fetus-related campylobacter species or other bovine venereal microflora. the 5' taq nuclease a ...200616517880
genome-wide screen for salmonella genes required for long-term systemic infection of the mouse.a microarray-based negative selection screen was performed to identify salmonella enterica serovar typhimurium (serovar typhimurium) genes that contribute to long-term systemic infection in 129x1/svj (nramp1(r)) mice. a high-complexity transposon-mutagenized library was used to infect mice intraperitoneally, and the selective disappearance of mutants was monitored after 7, 14, 21, and 28 d postinfection. one hundred and eighteen genes were identified to contribute to serovar typhimurium infectio ...200616518469
the helicobacter pylori chemotaxis receptor tlpb (hp0103) is required for ph taxis and for colonization of the gastric mucosa.the location of helicobacter pylori in the gastric mucosa of mammals is defined by natural ph gradients within the gastric mucus, which are more alkaline proximal to the mucosal epithelial cells and more acidic toward the lumen. we have used a microscope slide-based ph gradient assay and video data collection system to document ph-tactic behavior. in response to hydrochloric acid (hcl), h. pylori changes its swimming pattern from straight-line random swimming to arcing or circular patterns that ...200616547053
enumeration and identity of campylobacter spp. in italian broilers.transmission of campylobacter to humans has been prominently associated with mishandling or improperly preparing contaminated poultry carcasses. the number of organisms per carcass represents an important measure of human exposure to the agent. therefore, we wished to estimate this public exposure over 1 yr among italian broiler carcasses. we sampled 213 broiler carcasses from rinse water samples collected from a single slaughterhouse. groups of carcasses had mean processed weights ranging from ...200616553289
two distinct mutations in gyra lead to ciprofloxacin and nalidixic acid resistance in campylobacter coli and campylobacter jejuni isolated from chickens and beef cattle.the aim of this study was to identify point mutations in the gyra quinolone resistance determining region (qrdr) of campylobacter coli (n = 27) and campylobacter jejuni (n = 26) that confer nalidixic acid (nal) resistance without conferring resistance to ciprofloxacin (cip).200616553723
optimal settings of fingerprint-type analysing computer software for the analysis of enterohaemorrhagic escherichia coli pulsed-field gel electrophoresis patterns.settings of fingerprint-type analysing computer software were optimized for analysis of enterohaemorrhagic escherichia coli (ehec) pulsed-field gel electrophoresis (pfge) patterns. under the lowest values of parameters, maximum value of similarities calculated using the dice coefficient were obtained between pfge patterns from one ehec strain on the same gel when reference lanes for calibration of distortions during electrophoresis were set to every fourth lane. pfge patterns of 15 ehec strains ...200616566856
changes in flagellin glycosylation affect campylobacter autoagglutination and virulence.analysis of the complete flagellin glycosylation locus of campylobacter jejuni strain 81-176 revealed a less complex genomic organization than the corresponding region in the genome strain, c. jejuni nctc 11168. twenty-four of the 45 genes found between cj1293 and cj1337 in nctc 11168 are missing in 81-176. mutation of six new genes, in addition to three previously reported, resulted in a non-motile phenotype, consistent with a role in synthesis of pseudaminic acid (pseac) or transfer of pseac t ...200616573682
heterogeneity of campylobacter jejuni and campylobacter coli strains from healthy sheep.the objectives of this study were to identify, at species level, thermophilic campylobacters isolated from clinically healthy sheep by a multiplex polymerase chain reaction (mpcr). the heterogeneity among campylobacter jejuni and c. coli isolates was also investigated using a restriction fragment length polymorphism (rflp) analysis of the flagellin (flaa) gene. samples of intestinal contents, gall bladders and faeces were collected from 610 healthy sheep. while gall bladder samples were plated d ...200616574349
a phylogenomic profile of globins.globins occur in all three kingdoms of life: they can be classified into single-domain globins and chimeric globins. the latter comprise the flavohemoglobins with a c-terminal fad-binding domain and the gene-regulating globin coupled sensors, with variable c-terminal domains. the single-domain globins encompass sequences related to chimeric globins and "truncated" hemoglobins with a 2-over-2 instead of the canonical 3-over-3 alpha-helical fold.200616600051
campylobacter coli enteritis and guillain-barré syndrome: no evidence of molecular mimicry and serological relationship.campylobacter coli was isolated from two guillain-barré syndrome (gbs) patients who had anti-gm1 and anti-gd1 igg antibodies. although both this bacteria and campylobacter jejuni are common causes of diarrheal illness, previous studies have focused only on c. jejuni as the causal agent of gbs. to determine whether c. coli also is a causative agent, we examined the hypothesis that production of anti-ganglioside antibodies is induced by ganglioside-mimics on that bacterial lipo-oligosaccharide (lo ...200616600306
antibiotic resistance of retail food and human campylobacter isolates on the island of ireland from 2001-2002.the antimicrobial resistance profiles of campylobacter isolates recovered from a range of retail food samples (n=374) and humans (n=314) to eight antimicrobial compounds were investigated. high levels of resistance in food c. jejuni isolates were observed for ceftiofur (58%), ampicillin (25%) and nalidixic acid (17%) with lower levels observed for streptomycin (7.9%) and chloramphenicol (8.3%). a total of 80% of human c. jejuni isolates were resistant to ceftiofur, while 17% showed resistance to ...200616623987
quantification of campylobacter on the surface and in the muscle of chicken legs at retail.the objective of this study was to determine the prevalence and numbers of campylobacter on the skin and in the muscle of chicken legs at retail to examine the external and internal contamination for an exposure assessment. furthermore, the study assessed seasonal influence on campylobacter contamination in chicken legs. of the 140 examined skin samples, 66% were positive, and the internal contamination of 115 sampled chicken legs was 27%. the enumeration of campylobacter on the surface of posit ...200616629016
adherence to and invasion of human intestinal epithelial cells by campylobacter jejuni and campylobacter coli isolates from retail meat products.the abilities of 34 campylobacter jejuni and 9 campylobacter coli isolates recovered from retail meats to adhere to and invade human intestinal epithelial t84 cells were examined and compared with those of a well-characterized human clinical strain, c. jejuni 81-176, to better assess the pathogenic potential of these meat isolates. the meat isolates exhibited a wide range of adherence and invasion abilities; a few of the isolates adhered to and invaded t84 cells almost as well as did c. jejuni 8 ...200616629018
amplified fragment length polymorphism, serotyping, and quinolone resistance of campylobacter jejuni and campylobacter coli strains from chicken-related samples and humans in taiwan.the high-resolution genotyping method of amplified fragment length polymorphism (aflp) analysis was used to study the genetic relationships between campylobacter jejuni isolates from chicken-related samples (n = 32) and humans (n = 27) as well as between campylobacter coli isolates from chicken-related samples (n = 27) and humans (n = 5). these isolates were collected between 1994 and 2003 in taiwan. all c. jejuni and c. coli isolates showed highly heterogeneous fingerprints. c. jejuni isolates ...200616629019
prevalence of thermophilic campylobacter infections in humans, chickens and crows in morogoro, tanzania.prevalence of thermophilic campylobacter infections in humans, chickens and crows was determined in a cross-sectional study that was carried out in urban and rural areas of morogoro region, tanzania during the period of january 2003 to december 2004. a total of 632 human stool samples, 536 cloacal swabs from local and broiler chickens and 22 intestinal contents from crows were screened for presence of thermophilic campylobacters using skirrow's protocol. representative campylobacter jejuni isola ...200616629722
artificial neural network based identification of campylobacter species by fourier transform infrared spectroscopy.two prototypes of artificial neural network (ann), multilayer perceptron (mlp), and probabilistic neural network (pnn), were used to analyze infrared (ir) spectral data obtained from intact cells belonging to the species campylobacter coli and campylobacter jejuni. in order to establish a consistent identification and typing procedure, mid infrared spectra of these species were obtained by means of a fourier transform infrared (ft-ir) spectroscope. ft-ir patterns belonging to 26 isolates subclas ...200616632003
antimicrobial susceptibilities of thermophilic campylobacter from humans, swine, and chicken broilers.the aim of this study was to evaluate the incidence and the distribution of antimicrobial resistance, and the presence of genetic determinants of resistance, in campylobacter recovered from swine, poultry, and human populations in quebec. minimum inhibitory concentrations (mics) of 10 antimicrobial agents were determined by the agar dilution technique. polymerase chain reaction (pcr) was used to detect the teto determinant, and mutations in gyra were analyzed by sequencing and by mismatch amplif ...200616639939
molecular characterization of streptococcus suis strains by 16s-23s intergenic spacer polymerase chain reaction and restriction fragment length polymorphism analysis.we developed a new molecular method of typing streptococcus suis based on polymerase chain reaction (pcr) amplification of a large fragment of rrna genes, including a part of the 16s and 23s genes and the 16s-23s intergenic spacer region (isr), followed by restriction fragment length polymorphism (rflp) analysis with rsai or mboii endonuclease. the 16s-23s isrs of 5 s. suis isolates were sequenced and compared. size and sequence polymorphisms were observed between the s735 reference strain and t ...200616639941
recurrent outbreaks of cryptosporidiosis associated with calves among students at an educational farm programme, minnesota, 2003.enteric illness outbreaks among middle-/high-school students in consecutive semesters of an educational farm programme were investigated with retrospective cohort studies. during the first outbreak, 31/92 (34%) interviewed students were ill. risk factors included participating in animal science class (rr 8.1, 95% ci 1.2-55.2) and contact with calves (rr 4.2, 95% ci 1.1-16.2). stool samples from seven students and two calves yielded cryptosporidium parvum. students cared for animals in street clo ...200616672084
dissemination of fluoroquinolone-resistant campylobacter spp. within an integrated commercial poultry production system.while characterizing the intestinal bacterial community of broiler chickens, we detected epsilon-proteobacterial dna in the ilea of 3-day-old commercial broiler chicks (j. lu, u. idris, b. harmon, c. hofacre, j. j. maurer, and m. d. lee, appl. environ. microbiol. 69:6816-6824, 2003). the sequences exhibited high levels of similarity to campylobacter jejuni and campylobacter coli sequences, suggesting that chickens can carry campylobacter at a very young age. campylobacter sp. was detected by pcr ...200616672489
effect of conventional and organic production practices on the prevalence and antimicrobial resistance of campylobacter spp. in poultry.intestinal tracts of broilers and turkeys from 10 conventional broiler farms and 10 conventional turkey farms, where antimicrobials were routinely used, and from 5 organic broiler farms and 5 organic turkey farms, where antimicrobials had never been used, were collected and cultured for campylobacter species. a total of 694 campylobacter isolates from the conventional and organic poultry operations were tested for antimicrobial resistance to nine antimicrobial agents by the agar dilution method. ...200616672508
characterization of the arsrs regulon of helicobacter pylori, involved in acid adaptation.the human gastric pathogen helicobacter pylori is extremely well adapted to the highly acidic conditions encountered in the stomach. the pronounced acid resistance of h. pylori relies mainly on the ammonia-producing enzyme urease; however, urease-independent mechanisms are likely to contribute to acid adaptation. acid-responsive gene regulation is mediated at least in part by the arsrs two-component system consisting of the essential ompr-like response regulator arsr and the nonessential cognate ...200616672598
purification and spectroscopic characterization of ctb, a group iii truncated hemoglobin implicated in oxygen metabolism in the food-borne pathogen campylobacter jejuni.campylobacter jejuni is a food-borne bacterial pathogen that possesses two distinct hemoglobins, encoded by the ctb and cgb genes. the former codes for a truncated hemoglobin (ctb) in group iii, an assemblage of uncharacterized globins in diverse clinically and technologically significant bacteria. here, we show that ctb purifies as a monomeric, predominantly oxygenated species. optical spectra of ferric, ferrous, o(2)- and co-bound forms resemble those of other hemoglobins. however, resonance r ...200616681372
epidemiology and genetic characterization of shigella flexneri strains isolated from three paediatric populations in egypt (2000-2004).ninety-seven isolates of shigella flexneri from children seeking medical care from three sites in egypt were characterized. overall, 46.4% of children (median age 17 months) were febrile or reported blood in their stools, 25.8% were dehydrated and 16.5% were admitted to hospital. serotypes 2a (37.1%), 1b (18.6%), 1c (17.5%), and 6 (15.5%) comprised over 88.7% of the total isolates. we observed marked resistance to ampicillin (87.6%), tetracycline (84.5%) and trimethoprim-sulfamethoxazole (63.9%) ...200616690004
a large multi-pathogen waterborne community outbreak linked to faecal contamination of a groundwater system, france, 2000.a large waterborne outbreak of infection that occurred during august 2000 in a local community in france was investigated initially via a rapid survey of visits to local physicians. a retrospective cohort study was then conducted on a random cluster sample of residents. of 709 residents interviewed, 202 (28.5%) were definite cases (at least three liquid stools/day or vomiting) and 62 (8.7%) were probable cases (less than three liquid stools/day or abdominal pain). those who had drunk tap water h ...200616700706
genotyping of campylobacter coli and c. jejuni from retail chicken meat and humans with campylobacteriosis in slovenia and bosnia and herzegovina.thermotolerant campylobacter jejuni and c. coli are one of the major causes of bacterial foodborne enteric infection. consuming and/or handling poultry meat is the most consistent risk factor, linked to the high prevalence of campylobacters in retail poultry meat. the aim of the present study was to ascertain the genetic diversity and/or possible specificity of thermotolerant campylobacter isolates according to species (c. coli, c. jejuni), isolation source (retail chicken meat and human clinica ...200616712997
iha from an escherichia coli urinary tract infection outbreak clonal group a strain is expressed in vivo in the mouse urinary tract and functions as a catecholate siderophore receptor.virulence factors of pathogenic escherichia coli belonging to a recently emerged and disseminated clonal group associated with urinary tract infection (uti), provisionally designated clonal group a (cga), have not been experimentally investigated. we used a mouse model of ascending uti with cga member strain ucb34 in order to identify genes of cga that contribute to uti. iha was identified to be expressed by strain ucb34 in the mouse kidney using selective capture of transcribed sequences. iha f ...200616714573
flagellin-independent regulation of chemokine host defense in campylobacter jejuni-infected intestinal epithelium.campylobacter jejuni is a leading cause of bacterial food-borne diarrheal disease throughout the world and the most frequent antecedent of autoimmune neuropathy guillain-barré syndrome. while infection is associated with immune memory, little is known regarding the role of the epithelium in targeting dendritic cells (dc) for initiating the appropriate adaptive immune response to c. jejuni. the objective of this study was to define the role for the intestinal epithelium in the induction of the ad ...200616714574
effect of direct culture versus selective enrichment on the isolation of thermophilic campylobacter from feces of mature cattle at harvest.campylobacterjejuni and campylobacter coli are leading bacterial causes of human gastroenteritis in the united states and other industrialized nations. these organisms frequently colonize avian hosts, including commercial poultry, but are also found in the gastrointestinal tract of other warm-blooded animals, including swine, sheep, and cattle. this study investigated the effect of direct culture versus selective enrichment on the isolation of thermophilic campylobacter from the colon of 610 cat ...200616715799
occurrence of selected foodborne pathogens on poultry and poultry giblets from small retail processing operations in trinidad.we conducted a study to determine quantitatively and qualitatively the presence of campylobacter spp., escherichia coli, staphylococci, total coliforms, total aerobic bacteria, and salmonella on broiler carcasses from selected small retail processors in trinidad. we used standard media and procedures for detection and quantification. all carcass and weep samples were positive for aerobic bacteria, e. coli, total coliforms, and staphylococci. significant differences in the mean counts of aerobic ...200616715810
high genetic variation in the multidrug transporter cmeb gene in campylobacter jejuni and campylobacter coli.this study was conducted to examine the genetic variation occurring in the cmeb gene encoding the transporter component of the cmeabc efflux pump.200616735430
macrolide resistance in campylobacter jejuni and campylobacter coli.infection with campylobacter jejuni is now considered to be the most common cause of acute bacterial gastroenteritis in humans worldwide. it occurs more frequently than infections caused by salmonella species, shigella species, or escherichia coli o157:h7. although c. jejuni is also recognized for its association with serious post-infection neurological complications, most patients with c. jejuni infections have a self-limited illness. nevertheless, a substantial proportion of these infections a ...200616735431
glycosylation of b-type flagellin of pseudomonas aeruginosa: structural and genetic basis.the flagellin of pseudomonas aeruginosa can be classified into two major types-a-type or b-type-which can be distinguished on the basis of molecular weight and reactivity with type-specific antisera. flagellin from the a-type strain pak was shown to be glycosylated with a heterogeneous o-linked glycan attached to thr189 and ser260. here we show that b-type flagellin from strain pao1 is also posttranslationally modified with an excess mass of up to 700 da, which cannot be explained through phosph ...200616740946
temporal prevalence of antimicrobial resistance in campylobacter spp. from beef cattle in alberta feedlots.antimicrobial resistance (amr) was temporally assessed in campylobacters isolated from beef cattle (7,738 fecal samples from 2,622 animals) in four commercial feedlots in alberta. all calves were administered chlortetracycline and oxytetracycline in feed, and a majority of the animals (93%) were injected with long-acting oxytetracycline upon arrival at the feedlot. fecal samples from individual animals were collected upon arrival (i.e., entry sample), 69 days (standard deviation [sd] = 3 days) a ...200616751519
atypical helicobacter canadensis strains associated with swine.forty-two helicobacter isolates were isolated from swine feces in the netherlands and denmark. all 12 isolates sequenced (16s rrna gene) formed a robust clade with helicobacter canadensis ( approximately 99% similarity). species-specific pcr indicated that all of the isolates were h. canadensis isolates. although the appearance of the porcine isolates was similar to the appearance of h. canadensis, only one of these isolates was able to hydrolyze indoxyl acetate, a cardinal characteristic of thi ...200616751570
agdbnet - antigen sequence database software for bacterial typing.bacterial typing schemes based on the sequences of genes encoding surface antigens require databases that provide a uniform, curated, and widely accepted nomenclature of the variants identified. due to the differences in typing schemes, imposed by the diversity of genes targeted, creating these databases has typically required the writing of one-off code to link the database to a web interface. here we describe agdbnet, widely applicable web database software that facilitates simultaneous blast ...200616790057
the ability of flagellum-specific proteus vulgaris bacteriophage pv22 to interact with campylobacter jejuni flagella in culture.there has been a recent resurgent interest in bacteriophage biology. research was initiated to examine campylobacter jejuni-specific bacteriophage in the russian federation to develop alternative control measures for this pathogen.200616803630
analysis of campylobacter spp. contamination in broilers from the farm to the final meat cuts by using restriction fragment length polymorphism of the polymerase chain reaction products.we investigated the genotype diversity and dynamics of campylobacter jejuni and campylobacter coli in six commercial broiler farms during rearing and abattoir processing. in total, 223 c. jejuni and 36 c. coli strains isolated (on farm, transportation crates, carcasses after defeathering, and chicken wing meat at the end of the processing line) were subtyped by pcr-rflp based on flagellin (fla typing) gene. eleven (c. jejuni) and four (c. coli) different rflp patterns were found. multiple c. jej ...200616806554
cladophora (chlorophyta) spp. harbor human bacterial pathogens in nearshore water of lake michigan.cladophora glomerata, a macrophytic green alga, is commonly found in the great lakes, and significant accumulations occur along shorelines during the summer months. recently, cladophora has been shown to harbor high densities of the fecal indicator bacteria escherichia coli and enterococci. cladophora may also harbor human pathogens; however, until now, no studies to address this question have been performed. in the present study, we determined whether attached cladophora, obtained from the lake ...200616820442
helicobacter anseris sp. nov. and helicobacter brantae sp. nov., isolated from feces of resident canada geese in the greater boston area.numbers of nonmigratory canada geese have increased substantially in the past decade, and they have become a nuisance in some urban areas. because of their close contact with humans in parks and areas adjacent to surface waterways, contact with their feces poses a zoonotic risk. a total of 97 geese from 10 separate geographic locales in the greater boston area had their feces sampled for detection of helicobacter spp. identification of helicobacter spp. based on 16s rrna genus-specific helicobac ...200616820454
genotyping of campylobacter jejuni using seven single-nucleotide polymorphisms in combination with flaa short variable region sequencing.this investigation describes the development of a generally applicable, bioinformatics-driven, single-nucleotide polymorphism (snp) genotyping assay for the common bacterial gastrointestinal pathogen campylobacter jejuni. snps were identified in silico using the program 'minimum snps', which selects for polymorphisms providing the greatest resolution of bacterial populations based on simpson's index of diversity (d). the high-d snps identified in this study were derived from the combined c. jeju ...200616849726
unique features of a highly pathogenic campylobacter jejuni strain.campylobacter jejuni, a major human enteric pathogen, exhibits significant strain-to-strain differences which result in differences in pathogenic potential. c. jejuni 81-176 is a highly virulent strain that exhibits unique pathogenic features and is used by many research laboratories. we have determined the nucleotide sequence of its genome and compared it to the genomes of other sequenced c. jejuni strains. we identified a number of unique genetic features which may confer specific metabolic an ...200616861657
comparative, collaborative, and on-site validation of a taqman pcr method as a tool for certified production of fresh, campylobacter-free chickens.certified campylobacter-free poultry products have been produced in denmark since 2002, the first example of fresh (unprocessed and nonfrozen) chickens labeled "campylobacter free." this success occurred partly through use of a 4-hour gel-based pcr testing scheme on fecal swabs. in this study, a faster, real-time pcr approach was validated in comparative and collaborative trials, based on recommendations from the nordic system for validation of alternative microbiological methods (nordval). the ...200616885299
molecular epidemiologic investigation of campylobacter coli in swine production systems, using multilocus sequence typing.multilocus sequence typing of 151 campylobacter coli isolates from swine reared in conventional (n = 74) and antimicrobial-free (n = 77) production systems revealed high genotypic diversity. sequence type (st) 1413 was predominant and observed among ciprofloxacin-resistant strains. we identified a c. coli st 828 clonal complex consisting of isolates from both production systems.200616885327
efficacy of iron chelators on campylobacter concentrations in turkey semen.campylobacter is a leading bacterial cause of human foodborne infections in the united states. recent studies suggest that the organism is highly prevalent in poultry semen and may contribute to vertical transmission between the breeder hen and offspring. because campylobacter requires iron for its growth and survival, the objective of this study was to determine if the addition of natural and synthetic chelators such as ovotransferrin, desferrioxaime, edta, or 2,2'-dipyridyl could reduce or eli ...200616903479
synergy between efflux pump cmeabc and modifications in ribosomal proteins l4 and l22 in conferring macrolide resistance in campylobacter jejuni and campylobacter coli.macrolide-resistant mutants of campylobacter jejuni and campylobacter coli were selected in vitro using erythromycin and tylosin. these mutants exhibited modifications in the ribosomal proteins l4 (g74d) and l22 (insertions at position 86 or 98). a synergy between the cmeabc efflux pump and these modifications in conferring macrolide resistance was observed.200616940070
investigation for possible source(s) of contamination of ready-to-eat meat products with listeria spp. and other pathogens in a meat processing plant in trinidad.in 2003, there was a recall of three processed (chicken franks, spice ham and turkey ham ready-to-eat (rte) meat products by a large processing plant in trinidad as a result of contamination by listeria monocytogenes. the study was conducted to investigate the possible source(s) of listeria contamination of recalled rte meat products and to determine the prevalence of listeria spp., salmonella spp., escherichia coli and campylobacter spp. in the products and air within the plant. raw and process ...200616943025
in vitro antimicrobial susceptibility, genetic diversity and prevalence of udp-glucose 4-epimerase (gale) gene in campylobacter coli and campylobacter jejuni from turkey production facilities.this study evaluated the genetic diversity of multi-drug resistant campylobacter jejuni (n=44) and c. coli (n=30) isolated from 18 turkey houses. antimicrobial resistances to ampicillin, ciprofloxacin and nalidixic acid were higher (p<0.05) in c. coli than in c. jejuni strains. pcr analysis indicated that 82% of total isolates tested, including 91% of c. jejuni and 70% of c. coli tested positive for a 496-bp udp-glucose 4-epimerase (gale) gene. the diversity of isolates was mapped by antibiogram ...200616943028
comparative genomic analysis of campylobacter jejuni strains reveals diversity due to genomic elements similar to those present in c. jejuni strain rm1221.analysis of the complete genomic sequence of campylobacter jejuni strain rm1221 identified four large genomic elements, campylobacter jejuni-integrated elements (cjies), that were absent from c. jejuni strain nctc 11168. to further investigate the genomic diversity of campylobacter, we conducted a comparative genomic analysis from a collection of 67 c. jejuni and 12 campylobacter coli strains isolated from various geographical locations and clinical and veterinary sources. utilizing pcr, we demo ...200616943349
lack of evidence for vertical transmission of campylobacter spp. in chickens.campylobacter jejuni is a major cause of bacterial food-borne infection in the industrial world. there is evidence that c. jejuni is present in eggs and hatchery fluff, opening the possibility for vertical transmission from hens to progeny. poultry operations in iceland provide an excellent opportunity to study this possibility, since breeding flocks are established solely from eggs imported from grandparent flocks in sweden. this leaves limited opportunity for grandparents and their progeny to ...200616957196
comparison of campylobacter isolated from humans and food-producing animals in japan.to compare the antimicrobial resistance, serotypes and flagellin gene types of campylobacter isolated from humans and food-producing animals and thereby facilitate elucidation of the origin of campylobacter causing human infection in japan.200616405695
genetic characterization and antibiotic resistance of campylobacter spp. isolated from poultry and humans in senegal.the main objectives of this study were to investigate the diversity of campylobacter genotypes circulating in senegal and to determine the frequency of antibiotic resistance.200616405702
temperature dependence of reported campylobacter infection in england, 1989-1999.campylobacter is the most common bacterial cause of gastroenteritis in england and wales, with 45000 cases reported annually. campylobacter incidence is highly seasonal; the consistent peak in late spring suggests a role for meteorological factors in the epidemiology of this organism. we investigated the relationship between ambient temperature and campylobacter enteritis using time-series analysis to study short-term associations between temperature and number of campylobacter reports adjusted ...200616409658
temperature dependence of reported campylobacter infection in england, 1989-1999.campylobacter is the most common bacterial cause of gastroenteritis in england and wales, with 45000 cases reported annually. campylobacter incidence is highly seasonal; the consistent peak in late spring suggests a role for meteorological factors in the epidemiology of this organism. we investigated the relationship between ambient temperature and campylobacter enteritis using time-series analysis to study short-term associations between temperature and number of campylobacter reports adjusted ...200616409658
antimicrobial resistance in campylobacter jejuni from humans and broilers in norway.in this study comprising isolates from 2001 to 2003, resistance was considerably more widespread among campylobacter jejuni from humans infected abroad than infected within norway. the discrepancy was particularly notable for fluoroquinolone resistance (67.4% vs. 6.5%). this is probably a reflection of a low resistance prevalence in norwegian broiler isolates (1.2% fluoroquinolone resistant).200616409659
antimicrobial resistance in campylobacter jejuni from humans and broilers in norway.in this study comprising isolates from 2001 to 2003, resistance was considerably more widespread among campylobacter jejuni from humans infected abroad than infected within norway. the discrepancy was particularly notable for fluoroquinolone resistance (67.4% vs. 6.5%). this is probably a reflection of a low resistance prevalence in norwegian broiler isolates (1.2% fluoroquinolone resistant).200616409659
iron and ph homeostasis intersect at the level of fur regulation in the gastric pathogen helicobacter pylori.helicobacter pylori persistently colonizes the stomach of the majority of the world's population and is a tremendous medical burden due to its causal role in diverse gastric maladies. since the stomach is a constantly changing environment, successful colonization of h. pylori within this niche requires regulation of bacterial gene expression to cope with the environmental fluctuations. in h. pylori, the ferric uptake regulator (fur) has been shown to play an intricate role in adaptation of the b ...200616369017
new world monkey aotus nancymae as a model for campylobacter jejuni infection and immunity.three groups of six monkeys (aotus nancymae) each were inoculated intragastrically with increasing doses of campylobacter jejuni. infection resulted in fecal colonization (100% of monkeys), dose-related diarrhea, and robust immune responses. colonization duration and diarrhea rate were reduced upon secondary challenge. a. nancymae may be useful for studying anti-campylobacter vaccine efficacy.200616369042
xbase, a collection of online databases for bacterial comparative genomics.the schema of the previously described escherischia coli database colibase has been applied to a number of other bacterial taxa, under the collective name xbase. the new databases include campydb for campylobacter, helicobacter and wolinella; pseudodb for pseudomonads; clostridb for clostridia; rhizodb for rhizobium and sinorhizobium; and mycodb, for mycobacterium, streptomyces and related organisms. the databases provide user friendly access to annotation and genome comparisons through a web-ba ...200616381881
xbase, a collection of online databases for bacterial comparative genomics.the schema of the previously described escherischia coli database colibase has been applied to a number of other bacterial taxa, under the collective name xbase. the new databases include campydb for campylobacter, helicobacter and wolinella; pseudodb for pseudomonads; clostridb for clostridia; rhizodb for rhizobium and sinorhizobium; and mycodb, for mycobacterium, streptomyces and related organisms. the databases provide user friendly access to annotation and genome comparisons through a web-ba ...200616381881
identification of host-associated alleles by multilocus sequence typing of campylobacter coli strains from food animals.campylobacter coli is a food-borne pathogen associated increasingly with human gastroenteritis. c. coli has a high prevalence in swine, but is isolated also from cattle and poultry. multilocus sequence typing (mlst) systems have been developed to differentiate c. coli strains. although substantial allelic diversity was identified across all seven c. coli mlst loci, no correlations were made in two previous studies between allele or sequence type (st) and the source of the organism. however, this ...200616385134
stable concentrated emulsions of the 1-monoglyceride of capric acid (monocaprin) with microbicidal activities against the food-borne bacteria campylobacter jejuni, salmonella spp., and escherichia coli.of 11 fatty acids and monoglycerides tested against campylobacter jejuni, the 1-monoglyceride of capric acid (monocaprin) was the most active in killing the bacterium. various monocaprin-in-water emulsions were prepared which were stable after storage at room temperature for many months and which retained their microbicidal activity. a procedure was developed to manufacture up to 500 ml of 200 mm preconcentrated emulsions of monocaprin in tap water. the concentrates were clear and remained stabl ...200616391087
heat resistance and mechanism of heat inactivation in thermophilic campylobacters.the heat resistance of campylobacter jejuni strains ar6 and l51 and the heat resistance of campylobacter coli strains dr4 and l6 were measured over the temperature range from 50 to 60 degrees c by two methods. isothermal measurements yielded d55 values in the range from 4.6 to 6.6 min and z values in the range from 5.5 to 6.3 degrees c. dynamic measurements using differential scanning calorimetry (dsc) during heating at a rate of 10 degrees c/min yielded d55 values of 2.5 min and 3.4 min and z v ...200616391133
presence of salmonella and campylobacter spp. in wild small mammals on organic farms.the presence of salmonella and campylobacter spp. in rodents and insectivores (n = 282) was investigated on organic farms. infections were encountered in house mice (8 of 83 campylobacter positive and 1 of 83 salmonella sp. strain livingstone positive) and brown rats (1 of 8 campylobacter positive) but not in other species. no shared campylobacter genotypes were found between rodent and pig manure isolates. effective on-farm rodent management is recommended.200616391145
most campylobacter subtypes from sporadic infections can be found in retail poultry products and food animals.the subtypes of campylobacter isolates from human infections in two danish counties were compared to isolates from retail food samples and faecal samples from chickens, pigs and cattle. during a 1-year period, 1285 campylobacter isolates from these sources were typed by two methods: 'penner' heat-stable serotyping and automated ribotyping (riboprinting). c. jejuni was the dominating species, but c. coli was more prevalent among food and chicken isolates (16%) compared to human isolates (4%). in ...200616316490
an investigation of the molecular mechanisms contributing to high-level erythromycin resistance in campylobacter.the molecular mechanisms contributing to high-level erythromycin resistance in campylobacter jejuni and campylobacter coli isolates were investigated. the a2075g mutation in the 23s rrna target genes was identified in all high-level erythromycin-resistant isolates. a number of amino acid substitutions together with insertions and deletions were identified in the corresponding genes encoding l4 and l22 ribosomal proteins both of resistant and susceptible isolates. amino acid substitutions identif ...200616318913
sequence analysis of two cryptic plasmids from an agricultural isolate of campylobacter coli.as part of a study identifying plasmids in campylobacter, we isolated and sequenced two novel cryptic plasmids from an agricultural isolate of campylobacter coli. the larger of the two plasmids, p3384, is 3316 bp in length and has a g+c content of 31.18%. a typical origin of replication consisting of five iterons was observed directly upstream of the first of three putative orfs. the smaller plasmid, p3386, is 2426 bp in length and has a g+c content of 26.22%. of the three putative orfs detected ...200616120460
genetic diversity in fluoroquinolone and macrolide-resistant campylobacter coli from pigs.the genetic diversity of 115 campylobacter coli strains, isolated from pigs of 59 geographical distant farms in switzerland, were characterized on the basis of their dna fingerprints and resistance to macrolides and fluoroquinolones. sequence analysis showed that the macrolide-resistant isolates had a point mutation in the 23s ribosomal rna (rrna) genes (a2075g) and that the fluoroquinolone-resistant isolates had a point mutation in the gyrase gene gyra (c257t). one fluoroquinolone-resistant str ...200616289952
australian multicentre comparison of subtyping methods for the investigation of campylobacter infection.in order to identify subtyping methods able to contribute to the surveillance or investigation of australian campylobacter infection, six genotypic and three phenotypic subtyping methods were evaluated on a collection of 84 clinical isolates collected over a 30-month period from one region in australia. the aim was to compare the logistics of various subtyping methods and examine their ability to assist in finding outbreaks or common sources of sporadic infection. the genotypic subtyping methods ...200616436218
distribution of tetracycline resistance genes in actinobacillus pleuropneumoniae isolates from spain.actinobacillus pleuropneumoniae is the etiological agent of porcine pleuropneumonia. tetracycline is used for therapy of this disease, and a. pleuropneumoniae carrying the tet(b) gene, coding for an efflux protein that reduces the intercellular tetracycline level, has been described previously. of the 46 tetracycline-resistant (tc(r)) spanish a. pleuropneumoniae isolates used in this study, 32 (70%) carried the tet(b) gene, and 30 of these genes were associated with plasmids. eight (17%) isolate ...200616436729
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