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campylobacter contamination of broiler caeca and carcasses at the slaughterhouse and correlation with salmonella contamination.in order to estimate the prevalence of campylobacter spp. and salmonella spp. on broiler chicken carcasses and the prevalence of campylobacter spp. in caeca, 58 french slaughterhouses were investigated in 2008. enumeration of campylobacter spp. was also performed in order to study the relation between caeca and carcass contamination. a pool of 10 caeca and one carcass were collected from 425 different batches over a 12-month period in 2008. salmonella was isolated on 32 carcasses leading to a pr ...201121569927
influence of cell surface hydrophobicity on attachment of campylobacter to abiotic surfaces.this work aimed to investigate the influence of physicochemical properties and prior mode of growth (planktonic or sessile culture) on attachment of 13 campylobacter jejuni strains and 5 campylobacter coli strains isolated from chicken samples to three abiotic surfaces: stainless steel, glass and polyurethane. water contact angle and zeta potential measurements indicated that the strains varied with respect to surface hydrophobicity (17.6 ± 1.5 to 53.0 ± 2.3°) and surface charge (-3.3 ± 0.4 to - ...201121569937
metagenome of the gut of a malnourished child.abstract: background: malnutrition, a major health problem, affects a significant proportion of preschool children in developing countries. the devastating consequences of malnutrition include diarrhoea, malabsorption, increased intestinal permeability and suboptimal immune response etc. nutritional interventions and dietary solutions have not been effective for treatment of malnutrition till date. metagenomic procedures allow one to access the complex cross-talk between the gut and its microbia ...201121599906
rapid identification and quantification of campylobacter coli and campylobacter jejuni by real-time pcr in pure cultures and in complex samples.abstract: background: campylobacter spp., especially campylobacter jejuni (c. jejuni) and campylobacter coli (c. coli), are recognized as the leading human foodborne pathogens in developed countries. livestock animals carrying campylobacter pose an important risk for human contamination. pigs are known to be frequently colonized with campylobacter, especially c. coli, and to excrete high numbers of this pathogen in their faeces. molecular tools, notably real-time pcr, provide an effective, rapid ...201121600037
flagellar glycosylation in burkholderia pseudomallei and burkholderia thailandensis.glycosylation of proteins is known to impart novel physical properties and biological roles to proteins from both eukaryotes and prokaryotes. in this study, gel based glycoproteomics were used to identify glycoproteins of the potential bio-threat agent burkholderia pseudomallei and the closely related but non-pathogenic b. thailandensis. top-down and bottom-up ms analysis identified that the flagellin proteins of both species were post-translationally modified by novel glycans. analysis of prote ...201121602339
screening of australian plants for antimicrobial activity against campylobacter jejuni.campylobacter jejuni is the most common cause of acute enteritis in humans, with symptoms such as diarrhoea, fever and abdominal cramps. in this study, 115 extracts from 109 australian plant species were investigated for their antimicrobial activities against two c. jejuni strains using an in vitro broth microdilution assay. among the plants tested, 107 (93%) extracts showed activity at a concentration between 32 and 1024 µg/ml against at least one c. jejuni strain. seventeen plant extracts were ...201121604309
the utility of matrix assisted laser desorption/ionization time-of-flight mass spectrometry (maldi-tof ms) following introduction for routine laboratory bacterial identification.maldi-tof ms was evaluated prospectively in a diagnostic laboratory. 927 organisms were tested in triplicate; 2351/2781 (85%) species and 2681/2781 (96%) genus identifications were correct. known issues such as the misidentification of α-haemolytic streptococci as streptococcus pneumonia were easily corrected. identifications cost $aud0.45 per isolate and were available in minutes. maldi-tof ms is rapid, accurate and inexpensive.201121632894
blastocystis sp. subtype 4 is common in danish blastocystis-positive patients presenting with acute diarrhea.abstract. fecal samples from 444 danish patients presenting with acute diarrhea were tested for blastocystis and positive samples were subtyped to investigate the prevalence and subtype distribution of blastocystis in this patient group. a total of 25 patients (5.6%) were positive, and 19 of these patients (76.0%) were positive for blastocystis sp. st4. because the relative prevalence of st4 in other patients presenting with other types of diarrhea (persistent, travel-related, and human immunode ...201121633023
molecular epidemiology and antimicrobial susceptibility of campylobacter jejuni and campylobacter coli isolates of poultry, swine, and cattle origin collected from slaughterhouses in hungary.campylobacter spp. are the most common cause of bacterial enteritis in hungary, and the aim of this study was to identify the distribution, genotypes, and antimicrobial susceptibility of campylobacter species in the most important food-producing animals at the time of slaughter during 2008 and 2009. of 1,110 samples, 266 were identified as campylobacter coli (23.9%) and 143 as c. jejuni (12.9%) by real-time pcr. resistance to enrofloxacin-ciprofloxacin and nalidixic acid was significant, especia ...201121669066
regulation of oxidative stress response by cosr, an essential response regulator in campylobacter jejuni.cosr (campylobacteroxidative stress regulator; cj0355c) is an ompr-type response regulator essential for the viability of campylobacter jejuni, a leading foodborne pathogen causing human gastroenteritis worldwide. despite importance, the function of cosr remains completely unknown mainly because of cell death caused by its knockout mutation. to overcome this technical limitation, in this study, antisense technology was used to investigate the regulatory function of cosr by modulating the level o ...201121811584
genome and characterization of phages bcep22 and bcepil02, founders of a novel phage type in burkholderia cenocepacia.within the burkholderia cepacia complex (bcc), b. cenocepacia is the most common species associated with aggressive infections in the lungs of cystic fibrosis patients, causing disease that is often refractive to treatment by antibiotics. phage therapy may be a potential alternative form of treatment for these infections. here we describe the genome of the previously described therapeutic b. cenocepacia podophage bcepil02 and its close relative, bcep22. phage bcep22 was found to contain a circul ...201121804006
campylobacter from sows in farrow-to-finish pig farms: risk indicators and genetic diversity.sows have been identified as a source of campylobacter contamination in piglets. we carried out a one-year study, in 2008, at 53 farrow-to-finish farms in brittany, france, to determine the proportion of sows excreting campylobacter. we also determined the genotypes of the campylobacter isolates. moreover, generalized estimating equations including repeated effects were used to assess the association between management practices and farm characteristics, and risk of campylobacter shedding by sow ...201121802224
genomic species are ecological species as revealed by comparative genomics in agrobacterium tumefaciens.the definition of bacterial species is based on genomic similarities, giving rise to the operational concept of genomic species, but the reasons of the occurrence of differentiated genomic species remains largely unknown. we used the agrobacterium tumefaciens species complex, and particularly the genomic species presently called genomovar g8, which includes the sequenced strain c58, to test the hypothesis of genomic species having specific ecological adaptations possibly involved in the speciati ...201121795751
temporal variation and host association in the campylobacter population in a longitudinal ruminant farm study.campylobacter jejuni and c. coli was quantified and typed using multi-locus sequence typing (mlst) from fecal samples collected from a mixed cattle and sheep farm during summer. cattle had a significantly higher prevalence than sheep (21.9 % (74/338) and 14.0 % (30/214), respectively) but both reduced over time. there were no differences in the average campylobacter concentrations shed between cattle (600 cfu g(-1)) and sheep (820 cfu g(-1)), although sheep did show a significant temporal reduct ...201121784915
niche segregation and genetic structure of campylobacter jejuni populations from wild and agricultural host species.bacterial populations can display high levels of genetic structuring but the forces that influence this are incompletely understood. here, by combining modelling approaches with multilocus sequence data for the zoonotic pathogen campylobacter, we investigated how ecological factors such as niche (host) separation relate to population structure. we analysed seven housekeeping genes from published c. jejuni and c. coli isolate collections from a range of food and wild animal sources as well as abi ...201121762392
genetic instability of campylobacter coli in the digestive tract of experimentally infected pigs.campylobacter, a leading cause of food-borne illness worldwide, has a widespread distribution with a broad range of animal hosts and environmental reservoirs. the genetic description of bacterial strains is a powerful tool for epidemiological studies but can be impaired by the high genomic variability of campylobacter. our study aimed (i) at investigating the genotypic instability of campylobacter generated either in vitro by subculturing or after in vivo passage on specific pathogen-free pigs a ...201121831540
sequencing and validation of the genome of a campylobacter concisus reveals intra-species diversity.campylobacter concisus is an emerging pathogen of the human gastrointestinal tract. its role in different diseases remains a subject of debate; this may be due to strain to strain genetic variation. here, we sequence and analyze the genome of a c. concisus from a biopsy of a child with crohn's disease (unswcd); the second such genome for this species. a 1.8 mb genome was assembled with paired-end reads from a next-generation sequencer. this genome is smaller than the 2.1 mb c. concisus reference ...201121829448
allelic diversity and population structure of bacillus sphaericus as revealed by multilocus sequence typing.the genetic diversity of 35 bacillus sphaericus strains was analyzed by a newly developed multilocus sequence typing (mlst) scheme, toxin gene pool survey, and mosquito bioassay. the results demonstrated that strains assigned to the same sequence type (st) had the same occurrence of toxin genes. further sequence analysis revealed that toxic strains presented a nearly clonal population structure, whereas nontoxic strains had a high level of heterogeneity and were significantly distinct from toxic ...201121685170
genome sequence of campylobacter jejuni strain 327, a strain isolated from a turkey slaughterhouse.campylobacter is one of the leading causes of food-borne gastroenteritis and has a high prevalence in poultry. campylobacter jejuni subsp. jejuni 327 is a subspecies of the genus campylobacter of the family campylobacteraceae in the phylum proteobacteria. the microaerophilic, spiral shaped, catalase positive bacterium obtains energy from the metabolism of amino acids and krebs cycle intermediates. strain 327 was isolated from a turkey slaughter production line and is considered environmentally s ...201121677848
hygienic quality and antibiotic resistance profile of sliced butchery.in order to investigate the microbiological quality of different meat products on the greek market, 200 samples were collected from the following preparations: boiled turkey (n=50), boiled pork ham (n=50), smoked turkey (n=50) and smoked pork ham (n=50). in all cold meat preparations clostridium perfringens vegetative and spore forms, staphylococcus aureus, escherichia coli and other clostridium sp lec(-), as well as lactobacillus, bacillus sp. and salmonella sp. were recovered. for instance bac ...201121722746
the prevalence and genetic diversity of campylobacter spp. in domestic 'backyard' poultry in canterbury, new zealand.campylobacteriosis is the most commonly notified illness in new zealand. whilst the importance of commercial poultry in campylobacteriosis is well established, little is known about the possible role of chickens kept at home as a direct animal/faecal contact or consumption exposure pathway. the aim of this study was to determine the prevalence and genetic diversity of campylobacter spp. in domestic backyard chicken flocks in the canterbury region of new zealand. poultry faecal samples were colle ...201121824372
detection of campylobacter concisus and other campylobacter species in colonic biopsies from adults with ulcerative colitis.the critical role of bacteria in the pathogenesis of ulcerative colitis (uc) is well recognized, but an individual causative microorganism has not been singled out so far. campylobacter concisus and other non-jejuni species of campylobacter have been implicated as putative aetiological agents in inflammatory bowel disease in children, but such studies have not been addressed in adults. this study investigated the prevalence of campylobacter species in colonic biopsy samples from adults with uc a ...201121738679
structure and mechanism of rnd-type multidrug efflux pumps. 201121692366
Occurrence of virulence genes among Campylobacter jejuni and Campylobacter coli isolates from domestic animals and children.The presence of the flaA, cadF, cdtB and iam genes of Campylobacter spp. was determined with the PCR method. The materials to investigate were 56 C. jejuni and 23 C. coli strains isolated from clinical samples (children and domestic animals). It was found that all of the Campylobacter spp. isolates from children with diarrhoea and domestic animals had cadF gene, responsible for adherence. The flaA gene was present in all Campylobacter spp. isolates derived from children and cats. Occurrence of f ...201121721403
biosecurity-based interventions and strategies to reduce campylobacter spp. on poultry farms.the prevention and control of campylobacter colonization of poultry flocks are important public health strategies for the control of human campylobacteriosis. a critical review of the literature on interventions to control campylobacter in poultry on farms was undertaken using a systematic approach. although the focus of the review was on aspects appropriate to the united kingdom poultry industry, the research reviewed was gathered from worldwide literature. multiple electronic databases were em ...201121984249
Prevalence of Campylobacter and Salmonella in raw chicken on retail sale in the republic of Ireland.To assess the current risks to consumers from Campylobacter and Salmonella in raw chicken products sold in the Republic of Ireland, a retail survey was undertaken to define their prevalence. Samples (n = 510) were analyzed using protocols based on ISO 10272-1:2006 and ISO 6579:2002. Processor codes on pack labels showed that 67% of samples were produced in the Republic of Ireland and 25% in the United Kingdom. Salmonella was present in 5.1% of samples, but the eight serovars found caused less t ...201122054193
occurrences of thermophilic campylobacter in pigs slaughtered at morogoro slaughter slabs, tanzania.occurrences of thermophlic campylobacter in pigs and pig carcasses was investigated in a cross-sectional study that was carried out in three selected slaughter slabs in morogoro municipality, tanzania. before sampling, the slab hygiene, slaughter, carcass dressing, and meat handling was assessed. fecal samples were collected from 66 slaughter pigs at the kill floor. after slaughter, a 100-cm(2) area on medial surface of the thigh muscles of dressed carcasses was sampled using sterile cotton swab ...201120730490
do patients with recurrent episodes of campylobacteriosis differ from those with a single disease event?although campylobacter is the leading cause of reported bacterial gastro-enteritis in industrialized countries, little is known on its recurrence. the objective of this study is to describe the risk and the patient characteristics of recurrent episodes of human campylobacteriosis reported in quebec.201121226938
taxonomy, epidemiology, and clinical relevance of the genus arcobacter.the genus arcobacter, defined almost 20 years ago from members of the genus campylobacter, has become increasingly important because its members are being considered emergent enteropathogens and/or potential zoonotic agents. over recent years information that is relevant for microbiologists, especially those working in the medical and veterinary fields and in the food safety sector, has accumulated. recently, the genus has been enlarged with several new species. the complete genomes of arcobacte ...201121233511
survival of escherichia coli, enterococci, and campylobacter spp. in sheep feces on pastures.the survival of enteric bacteria in 10 freshly collected sheep fecal samples on pastures was measured in each of four seasons. ten freshly collected feces were placed on pasture, and concentrations of escherichia coli, enterococci, and campylobacter spp. were monitored until exhaustion of the fecal samples. in all four seasons, there was an increase in enterococcal concentrations by up to 3 orders of magnitude, with peak concentrations recorded between 11 and 28 days after deposition. e. coli co ...201121239546
persistence of free-living protozoan communities across rearing cycles in commercial poultry houses.the introduction and survival of zoonotic bacterial pathogens in poultry farming have been linked to bacterial association with free-living protozoa. to date, however, no information is available on the persistence of protozoan communities in these environments across consecutive rearing cycles and how it is affected by farm- and habitat-specific characteristics and management strategies. we therefore investigated the spatial and temporal dynamics of free-living protozoa in three habitats (pipel ...201121239551
neurologic symptoms associated with raising poultry and swine among participants in the agricultural health study.guillain-barré syndrome (gbs) is the leading cause of acute peripheral neuropathy worldwide, often associated with recent foodborne infection with campylobacter jejuni. in this cross-sectional analysis of data from the agricultural health study, we tested whether swine and poultry exposure were associated with increased prevalence of gbs-like neurologic symptoms.201121270654
campylobacter troglodytis sp. nov., isolated from feces of human-habituated wild chimpanzees (pan troglodytes schweinfurthii) in tanzania.the transmission of simian immunodeficiency and ebola viruses to humans in recent years has heightened awareness of the public health significance of zoonotic diseases of primate origin, particularly from chimpanzees. in this study, we analyzed 71 fecal samples collected from 2 different wild chimpanzee (pan troglodytes) populations with different histories in relation to their proximity to humans. campylobacter spp. were detected by culture in 19/56 (34%) group 1 (human habituated for research ...201121278267
epidemiological association of different campylobacter jejuni groups with metabolism-associated genetic markers.in this study, multilocus sequence typing (mlst) was combined with the genetic detection of six genetic markers, ansb, dmsa, ggt, cj1585c, cjj81176-1367/71 (cj1365c), and the two-gene marker tlp7 (cj0951c plus cj0952c), to assess if their presence correlated with different c. jejuni clonal groups. using a collection of 266 c. jejuni isolates from (in decreasing order of sample size) humans, chickens, cattle, and turkeys, it was further investigated whether the resulting genotypes correlated with ...201121278270
new methods for detection of campylobacters in stool samples in comparison to culture.campylobacter species, especially campylobacter jejuni and campylobacter coli, are a major cause of human bacterial enteritis. current detection in stools is done essentially by culture on selective and nonselective media with filtration. these methods were compared to 2 molecular biology methods, an in-house real-time pcr and a multiplex pcr named seeplex diarrhea ace detection, and 3 immunoenzymatic methods, premier campy, ridascreen campylobacter, and immunocard stat!campy. out of 242 stool s ...201121209172
carry-over of thermophilic campylobacter spp. between sequential and adjacent poultry flocks.nineteen flocks of four poultry species were monitored at a veterinary field station to investigate the distribution and spread of campylobacter genotypes between sequential and adjacent flocks. caecal and liver samples were obtained at frequent intervals from birds of all flocks and examined for campylobacter. amplified fragment length polymorphism (aflp) analysis was performed to genotype campylobacter isolates. of the 1643 caecal and liver samples investigated, 452 (27.5%) caecal samples and ...201120619560
phenotypic and genotypic methods for typing campylobacter jejuni and campylobacter coli in poultry.human campylobacteriosis, an infection caused by the bacterium campylobacter, is a major issue in the united states food system, especially for poultry products. according to the center for disease control, campylobacterosis is estimated to affect over 2.4 million people annually. campylobacter jejuni and campylobacter coli are 2 species responsible for the majority of campylobacterosis infections. phenotypic and genotypic typing methods are often used to discriminate between bacteria at the spe ...201222184452
Genotypes and Antibiotic Resistances of Campylobacter jejuni and Campylobacter coli Isolates from Domestic and Travel-Associated Human Cases.Multilocus sequence typing (MLST) extended with flaB typing of 425 Campylobacter jejuni isolates and 42 Campylobacter coli isolates revealed quite a low overlap between human isolates from travel-associated and domestic cases in Switzerland. Men were more frequently affected by Campylobacter than women, but strains from women and, overall, from travel-associated cases showed mutations conferring quinolone resistance more frequently than strains from men and domestic cases, respectively.201222020515
Inaccuracy of the Disk Diffusion Method Compared with the Agar Dilution Method for Susceptibility Testing of Campylobacter spp.The agar dilution method has been standardized by the CLSI for the susceptibility testing of Campylobacter species, and according to these standards, the disk diffusion method should be used only in screening for macrolide and ciprofloxacin resistance. Nevertheless, the disk diffusion test is currently widely used, since it is easy to perform in clinical microbiology laboratories. In this study, the disk diffusion method was compared to the agar dilution method by analyzing the in vitro activiti ...201222075583
fecal indicators and zoonotic pathogens in household drinking water taps fed from rainwater tanks in southeast queensland, australia.in this study, the microbiological quality of household tap water samples fed from rainwater tanks was assessed by monitoring the numbers of escherichia coli bacteria and enterococci from 24 households in southeast queensland (seq), australia. quantitative pcr (qpcr) was also used for the quantitative detection of zoonotic pathogens in water samples from rainwater tanks and connected household taps. the numbers of zoonotic pathogens were also estimated in fecal samples from possums and various s ...201222020514
Simultaneous Detection of Six Diarrhea-Causing Bacterial Pathogens with an In-House PCR-Luminex Assay.Diarrhea can be caused by a range of pathogens, including several bacteria. Conventional diagnostic methods, such as culture, biochemical tests, and enzyme-linked immunosorbent assay (ELISA), are laborious. We developed a 7-plex PCR-Luminex assay to simultaneously screen for several of the major diarrhea-causing bacteria directly in fecal specimens, including pathogenic Aeromonas, Campylobacter jejuni, Campylobacter coli, Salmonella, Shigella, enteroinvasive Escherichia coli (EIEC), Vibrio, and ...201222075596
biophysical and bioinformatic analyses implicate the treponema pallidum tp34 lipoprotein (tp0971) in transition metal homeostasis.metal ion homeostasis is a critical function of many integral and peripheral membrane proteins. the genome of the etiologic agent of syphilis, treponema pallidum, is compact and devoid of many metabolic enzyme genes. nevertheless, it harbors genes coding for homologs of several enzymes that typically require either iron or zinc. the product of the tp0971 gene of t. pallidum, designated tp34, is a periplasmic lipoprotein that is thought to be tethered to the inner membrane of this organism. previ ...201223042995
reproductive clonality of pathogens: a perspective on pathogenic viruses, bacteria, fungi, and parasitic protozoa.we propose that clonal evolution in micropathogens be defined as restrained recombination on an evolutionary scale, with genetic exchange scarce enough to not break the prevalent pattern of clonal population structure, a definition already widely used for all kinds of pathogens, although not clearly formulated by many scientists and rejected by others. the two main manifestations of clonal evolution are strong linkage disequilibrium (ld) and widespread genetic clustering ("near-clading"). we hyp ...201222949662
efficacy of parenteral vaccination against porcine circovirus type 2 (pcv2) in seropositive piglets.this study investigated if parenteral administration of a prototype adjuvanted vaccine against porcine circovirus type 2 (pcv2) could override maternally derived antibodies and induce acquired immunity in young piglets. piglets with high levels of maternal pcv2 antibodies at 1 wk of age were randomly grouped into vaccinates and controls on the basis of body weight and inoculated with the vaccine or a control preparation twice, with an interval of 3 wk. both groups were challenged 3 wk after the ...201223543956
molecular characterization and antibiotic resistance profiling of campylobacter isolated from cattle in polish slaughterhouses.a total of 812 samples from bovine hides and the corresponding carcasses collected at the slaughterhouse level in the eastern part of poland were examined for the presence of campylobacter jejuni and campylobacter coli. recovered isolates were confirmed using species-specific pcr, characterized by the presence of 11 putative virulence genes and antimicrobial susceptibility was determined using a microbroth dilution method. furthermore, the genotypic relatedness of the isolates was determined by ...201223498189
a longitudinal study on thermophilic campylobacter spp. in commercial turkey flocks in northern italy: occurrence and genetic diversity.poultry are recognized as a main reservoir of thermophilic campylobacters, but few studies have been carried out on commercial meat turkeys. this study was aimed at assessing the occurrence of thermophilic campylobacter spp., their genetic diversity, and the trend of the infection during the whole production cycle of three turkey flocks from different farms in northern italy. flocks were monitored from the time of housing 1-day-old poults to slaughter time by collecting samples (meconium and clo ...201223397840
actinobaculum suis detection using polymerase chain reaction.actinobaculum suis is an important agent related to urinary infection in swine females. due to its fastidious growth characteristics, the isolation of this anaerobic bacterium is difficult, thus impairing the estimation of its prevalence. the purpose of this study was to develop and test a polymerase chain reaction (pcr) for the detection and identification of a. suis and then compare these results with traditional isolation methods. bacterial isolation and pcr were performed on one hundred and ...201223346017
development of antimicrobial resistance in campylobacter jejuni and campylobacter coli adapted to biocides.the potential for adaptive resistance of campylobacter jejuni and campylobacter coli after step-wise exposure to increasing sub-inhibitory concentrations of five biocides as triclosan, benzalkonium chloride, cetylpyridinium chloride, chlorhexidine diacetate and trisodium phosphate, was investigated, to identify the mechanisms underlying resistance. the biocide resistance and cross-resistance to the antimicrobials erythromycin and ciprofloxacin, and to sodium dodecyl sulphate, were examined accor ...201223290239
comparative characterization of the virulence gene clusters (lipooligosaccharide [los] and capsular polysaccharide [cps]) for campylobacter coli, campylobacter jejuni subsp. jejuni and related campylobacter species.campylobacter jejuni subsp. jejuni and campylobacter coli are leading causes of gastroenteritis, with virulence linked to cell surface carbohydrate diversity. although the associated gene clusters are well studied for c. jejuni subsp. jejuni, c. coli has been largely neglected. here we provide comparative analysis of the lipooligosaccharide (los) and capsular polysaccharide (cps) gene clusters, using genome and cluster sequence data for 36 c. coli strains, 67 c. jejuni subsp. jejuni strains and ...201223279811
comparative characterization of the virulence gene clusters (lipooligosaccharide [los] and capsular polysaccharide [cps]) for campylobacter coli, campylobacter jejuni subsp. jejuni and related campylobacter species.campylobacter jejuni subsp. jejuni and campylobacter coli are leading causes of gastroenteritis, with virulence linked to cell surface carbohydrate diversity. although the associated gene clusters are well studied for c. jejuni subsp. jejuni, c. coli has been largely neglected. here we provide comparative analysis of the lipooligosaccharide (los) and capsular polysaccharide (cps) gene clusters, using genome and cluster sequence data for 36 c. coli strains, 67 c. jejuni subsp. jejuni strains and ...201223279811
identification and characterization of a periplasmic trilactone esterase, cee, revealed unique features of ferric enterobactin acquisition in campylobacter.ferric enterobactin (feent) acquisition is a highly efficient and conserved iron scavenging system in gram-negative bacteria. recently, we have characterized two feent receptors (cfra and cfrb) in campylobacter jejuni and c. coli, the enteric human pathogens that do not produce any siderophores. in this study, whole-genome sequencing and comparative genomic analysis identified a unique ent trilactone esterase cee (cj1376) in c. jejuni. genomic analysis and biochemical assay strongly suggested th ...201223278903
identification and characterization of a periplasmic trilactone esterase, cee, revealed unique features of ferric enterobactin acquisition in campylobacter.ferric enterobactin (feent) acquisition is a highly efficient and conserved iron scavenging system in gram-negative bacteria. recently, we have characterized two feent receptors (cfra and cfrb) in campylobacter jejuni and c. coli, the enteric human pathogens that do not produce any siderophores. in this study, whole-genome sequencing and comparative genomic analysis identified a unique ent trilactone esterase cee (cj1376) in c. jejuni. genomic analysis and biochemical assay strongly suggested th ...201223278903
mutational and transcriptomic changes involved in the development of macrolide resistance in campylobacter jejuni.macrolide antibiotics are important for clinical treatment of infections caused by campylobacter jejuni. development of resistance to this class of antibiotics in campylobacter is a complex process, and the dynamic molecular changes involved in this process remain poorly defined. multiple lineages of macrolide-resistant mutants were selected by stepwise exposure of c. jejuni to escalating doses of erythromycin or tylosin. mutations in target genes were determined by dna sequencing, and the dynam ...201223274667
antimicrobial resistance in campylobacter spp. isolated from ontario sheep flocks and associations between antimicrobial use and antimicrobial resistance.the objectives of this study were to determine the prevalence of antimicrobial resistance (amr) in faecal campylobacter spp. from lambs and adult sheep and associations between antimicrobial use (amu) and amr. a total of 275 faecal samples collected during initial and final visits from 51 sheep flocks, including one feedlot, across southern ontario were tested for the presence of campylobacter spp. campylobacter jejuni was detected in 52% (143/275) of the faecal samples, campylobacter coli in 7% ...201222273455
detection and quantification of campylobacter jejuni and campylobacter coli using real-time multiplex pcr.aims:  we describe a real-time multiplex pcr (qmpcr) assay to identify and discriminate between isolates of campylobacter jejuni and campylobacter coli. methods and results:  two novel sets of primers and hydrolysis probes were designed to amplify the unique dna sequences within the hipo, ccon and cadf genes that are specific to c. jejuni and c. coli. by using the designed optimized qmpcr assay conditions, the amplification efficiency is in range from 108 to 116%. these qmpcr assays are highly s ...201222256961
investigation of chemical rinses suitable for very small meat plants to reduce pathogens on beef surfaces.numerous antimicrobial interventions are capable of reducing the prevalence of harmful bacteria on raw meat products. there is a need to identify effective and inexpensive antimicrobial interventions that could, in practice, be used in very small meat plants because of limited financial, space, and labor resources. eight antimicrobial compounds (acetic acid, citric acid, lactic acid, peroxyacetic acid, acidified sodium chlorite, chlorine dioxide, sodium hypochlorite, and aqueous ozone) were app ...201222221350
progressive genome-wide introgression in agricultural campylobacter coli.hybridization between distantly related organisms can facilitate rapid adaptation to novel environments, but is potentially constrained by epistatic fitness interactions among cell components. the zoonotic pathogens campylobacter coli and c. jejuni differ from each other by around 15% at the nucleotide level, corresponding to an average of nearly 40 amino acids per protein-coding gene. using whole genome sequencing, we show that a single c. coli lineage, which has successfully colonized an agric ...201223279096
progressive genome-wide introgression in agricultural campylobacter coli.hybridization between distantly related organisms can facilitate rapid adaptation to novel environments, but is potentially constrained by epistatic fitness interactions among cell components. the zoonotic pathogens campylobacter coli and c. jejuni differ from each other by around 15% at the nucleotide level, corresponding to an average of nearly 40 amino acids per protein-coding gene. using whole genome sequencing, we show that a single c. coli lineage, which has successfully colonized an agric ...201223279096
diagnostic microbiologic methods in the gems-1 case/control study.to understand the etiology of moderate-to-severe diarrhea among children in high mortality areas of sub-saharan africa and south asia, we performed a comprehensive case/control study of children aged <5 years at 7 sites. each site employed an identical case/control study design and each utilized a uniform comprehensive set of microbiological assays to identify the likely bacterial, viral and protozoal etiologies. the selected assays effected a balanced consideration of cost, robustness and perfo ...201223169941
investigation of motility and biofilm formation by intestinal campylobacter concisus strains.motility helps many pathogens swim through the highly viscous intestinal mucus. given the differing outcomes of campylobacter concisus infection, the motility of eight c. concisus strains isolated from patients with crohn's disease (n=3), acute (n=3) and chronic (n=1) gastroenteritis and a healthy control (n=1) were compared. following growth on solid or liquid media the eight strains formed two groups; however, the type of growth medium did not affect motility. in contrast, following growth in ...201223241133
evaluation of the positive predictive value of a rapid immunochromatographic test to detect campylobacter in stools.the recently developed rapid immunochromatographic tests (ict) have the potential to provide a quick and easy diagnosis of campylobacter enteritis in comparison to culture. in a previous study we found them sensitive but lacking in specificity. the aim of the present study was to focus on the problem of specificity and determine the positive predictive value (ppv) of a positive result of the immunocard stat! campy (meridian bioscience, cincinnati, oh, usa). for this purpose, the stools positive ...201223206554
bioluminescent enzyme immunoassay for the detection of norovirus capsid antigen.an ultrasensitive and fully automated bioluminescent enzyme immunoassay (bleia) was developed for the detection of norovirus (nv) capsid antigen. in the evaluation tests with recombinant virus-like particles, the bleia demonstrated broad reactivity against several nv genotypes (genotypes 1, 3, 4, 7, 8, and 12 in genogroup i [gi] and genotypes 1, 2, 3, 4, 5, 6, 12, and 13 in gii), a wide dose-response range from 0.25 pg/ml to 10,000 pg/ml, and good reproducibility with low coefficients of variati ...201223081816
chromosomal tet(o)-harboring regions in campylobacter coli isolates from turkeys and swine.in turkey-derived campylobacter coli isolates of a unique lineage (cluster ii), the tetracycline resistance determinant tet(o) was chromosomal and was part of a gene cassette (transposon) interrupting a campylobacter jejuni-associated putative citrate transporter gene. in contrast, the swine-derived c. coli strain 6461 harbored a chromosomal tet(o) in a different genomic location.201223023744
live virus-free or die: coupling of antivirus immunity and programmed suicide or dormancy in prokaryotes.the virus-host arms race is a major theater for evolutionary innovation. archaea and bacteria have evolved diverse, elaborate antivirus defense systems that function on two general principles: i) immune systems that discriminate self dna from nonself dna and specifically destroy the foreign, in particular viral, genomes, whereas the host genome is protected, or ii) programmed cell suicide or dormancy induced by infection.201223151069
immunogenomics for identification of disease resistance genes in pigs: a review focusing on gram-negative bacilli.over the past years, infectious disease has caused enormous economic loss in pig industry. among the pathogens, gram negative bacteria not only cause inflammation, but also cause different diseases and make the pigs more susceptible to virus infection. vaccination, medication and elimination of sick pigs are major strategies of controlling disease. genetic methods, such as selection of disease resistance in the pig, have not been widely used. recently, the completion of the porcine whole genome ...201223137309
association of campylobacter upsaliensis with persistent bloody diarrhea.campylobacter upsaliensis is a zoonotic, emerging pathogen that is not readily recovered in traditional stool culture. this case represents the first report of persistent bloody diarrhea with c. upsaliensis that was confirmed by filtration culture, pcr, and sequencing.201222915607
identification of cj1051c as a major determinant for the restriction barrier of campylobacter jejuni strain nctc11168.campylobacter jejuni is a leading cause of human diarrheal illness in the world, and research on it has benefitted greatly by the completion of several genome sequences and the development of molecular biology tools. however, many hurdles remain for a full understanding of this unique bacterial pathogen. one of the most commonly used strains for genetic work with c. jejuni is nctc11168. while this strain is readily transformable with dna for genomic recombination, transformation with plasmids is ...201222923403
prevalence and antimicrobial resistance of thermophilic campylobacter isolated from chicken in côte d'ivoire.thermophilic campylobacters are major causes of gastroenteritis in human. the main risk factor of infection is consumption of contaminated or by cross-contaminated poultry meat. in côte d'ivoire, gastroenteritis is usually observed but no case of human campylobacteriosis has been formally reported to date. the aims of this study were to determine prevalence and antimicrobial resistance of campylobacter jejuni and campylobacter coli isolated from chickens ceaca in commercial slaughter in abidjan. ...201223133454
bacterial toxin modulation of the eukaryotic cell cycle: are all cytolethal distending toxins created equally?the cytolethal distending toxins (cdts) comprise a family of intracellular-acting bacterial protein toxins whose actions upon eukaryotic cells result in several consequences, the most characteristic of which is the induction of g(2)/m cell cycle arrest. most cdts are hetero-tripartite assemblies of cdta, cdtb, and cdtc, with cdtb required for cdt-mediated cell cycle arrest. several lines of evidence indicate that cdta and cdtc are required for the optimal intracellular activity of cdtb, although ...201223061054
a longitudinal 6-year study of the molecular epidemiology of clinical campylobacter isolates in oxfordshire, united kingdom.temporal and seasonal trends in campylobacter genotypes causing human gastroenteritis were investigated in a 6-year study of 3,300 recent isolates from oxfordshire, united kingdom. genotypes (sequence types [st]) were defined using multilocus sequence typing and assigned to a clonal complex (a cluster of related strains that share four or more identical alleles with a previously defined central genotype). a previously undescribed clonal complex (st-464) was identified which, together with st-42, ...201222814466
identification of a novel genomic island conferring resistance to multiple aminoglycoside antibiotics in campylobacter coli.historically, the incidence of gentamicin resistance in campylobacter has been very low, but recent studies reported a high prevalence of gentamicin-resistant campylobacter isolated from food-producing animals in china. the reason for the high prevalence was unknown and was addressed in this study. pcr screening identified aminoglycoside resistance genes apha-3 and apha-7 and the aade-sat4-apha-3 cluster among 41 campylobacter isolates from broiler chickens. importantly, a novel genomic island c ...201222869568
regulation of energy metabolism by the extracytoplasmic function (ecf) σ factors of arcobacter butzleri.the extracytoplasmic function (ecf) σ factors are fundamental for bacterial adaptation to distinct environments and for survival under different stress conditions. the emerging pathogen arcobacter butzleri possesses seven putative pairs of σ/anti-σ factors belonging to the ecf family. here, we report the identification of the genes regulated by five out of the seven a. butzleri ecf σ factors. three of the ecf σ factors play an apparent role in transport, energy generation and the maintenance of ...201223028624
case-control study of the etiology of infant diarrheal disease in 14 districts in madagascar.acute diarrhea is a major cause of childhood morbidity and mortality worldwide. its microbiological causes and clinico-epidemiological aspects were examined during the rainy seasons from 2008 to 2009 in 14 districts in madagascar.201223028555
phylogenetic analysis reveals common antimicrobial resistant campylobacter coli population in antimicrobial-free (abf) and commercial swine systems.the objective of this study was to compare the population biology of antimicrobial resistant (ar) campylobacter coli isolated from swine reared in the conventional and antimicrobial-free (abf) swine production systems at farm, slaughter and environment. a total of 200 c. coli isolates selected from fecal, environmental, and carcass samples of abf (n = 100) and conventional (n = 100) swine production systems were typed by multilocus sequence typing (mlst). sequence data from seven housekeeping ge ...201222984540
a convenient and robust in vivo reporter system to monitor gene expression in the human pathogen helicobacter pylori.thirty years of intensive research have significantly contributed to our understanding of helicobacter pylori biology and pathogenesis. however, the lack of convenient genetic tools, in particular the limited effectiveness of available reporter systems, has notably limited the toolbox for fundamental and applied studies. here, we report the construction of a bioluminescent h. pylori reporter system based on the photorhabdus luminescens luxcdabe cassette. the system is constituted of a promoterle ...201222773640
detection of kudoa septempunctata 18s ribosomal dna in patient fecal samples from novel food-borne outbreaks caused by consumption of raw olive flounder (paralichthys olivaceus).kudoa septempunctata is a newly identified myxosporean parasite of olive flounder (paralichthys olivaceus) and a suspected causative agent of several food-borne gastroenteritis outbreaks in japan. here, we report the detection of k. septempunctata 18s ribosomal dna in fecal samples of outbreak patients using an efficient method based on real-time pcr. we first performed a spiking experiment to assess whether our previously developed real-time pcr assay was applicable to detect k. septempunctata ...201222760033
analysis of helicobacter pylori caga promoter elements required for salt-induced upregulation of caga expression.helicobacter pylori infection and consumption of a high-salt diet are each associated with an increased risk for the development of gastric cancer. to investigate potential synergism between these factors, we used a global proteomic approach to analyze h. pylori strains cultured in media containing varying salt concentrations. among the differentially expressed proteins identified, caga exhibited the greatest increase in expression in response to high salt concentrations. analysis of 36 h. pylor ...201222710874
outcome of infection of c57bl/6 il-10(-/-) mice with campylobacter jejuni strains is correlated with genome content of open reading frames up- and down-regulated in vivo.human campylobacter jejuni infection can result in an asymptomatic carrier state, watery or bloody diarrhea, bacteremia, meningitis, or autoimmune neurological sequelae. infection outcomes of c57bl/6 il-10(-/-) mice orally infected with twenty-two phylogenetically diverse c. jejuni strains were evaluated to correlate colonization and disease phenotypes with genetic composition of the strains. variation between strains was observed in colonization, timing of development of clinical signs, and occ ...201222960579
outcome of infection of c57bl/6 il-10(-/-) mice with campylobacter jejuni strains is correlated with genome content of open reading frames up- and down-regulated in vivo.human campylobacter jejuni infection can result in an asymptomatic carrier state, watery or bloody diarrhea, bacteremia, meningitis, or autoimmune neurological sequelae. infection outcomes of c57bl/6 il-10(-/-) mice orally infected with twenty-two phylogenetically diverse c. jejuni strains were evaluated to correlate colonization and disease phenotypes with genetic composition of the strains. variation between strains was observed in colonization, timing of development of clinical signs, and occ ...201222960579
analysis of evolutionary patterns of genes in campylobacter jejuni and c. coli. 201222929701
campylobacter antimicrobial resistance in peru: a ten-year observational study.campylobacter jejuni and campylobacter coli are food-borne pathogens of great importance and feature prominently in the etiology of developing world enteritis and travellers' diarrhoea. increasing antimicrobial resistant campylobacter prevalence has been described globally, yet data from peru is limited. our objective was to describe the prevalence trends of fluoroquinolone and macrolide-resistant c. jejuni and c. coli stool isolates from three regions in peru over a ten-year period.201222898609
acid stress response and protein induction in campylobacter jejuni isolates with different acid tolerance.during the transmission route from poultry to the human host, the major foodborne pathogen c. jejuni may experience many types of stresses, including low ph caused by different acids. however, not all strains are equally sensitive to the stresses. the aim of this study was to investigate the response to acid stress of three sequenced c. jejuni strains with different acid tolerances using hcl and acetic acid.201222889088
the intermediate region of helicobacter pylori vaca is a determinant of toxin potency in a jurkat t cell assay.colonization of the human stomach with helicobacter pylori is a risk factor for peptic ulceration, noncardia gastric adenocarcinoma, and gastric lymphoma. the secreted vaca toxin is an important h. pylori virulence factor that causes multiple alterations in gastric epithelial cells and t cells. several families of vaca alleles have been described, and h. pylori strains containing certain vaca types (s1, i1, and m1) are associated with an increased risk of gastric disease, compared to strains con ...201222585965
the complete genome sequence of bacteriophage cp21 reveals modular shuffling in campylobacter group ii phages.campylobacter group ii phages described so far share a high degree of sequence similarity. we report the 182,833-bp genomic sequence of the closely related group ii phage cp21 and show that it has a completely different genomic organization. as in other group ii phages, the cp21 genome is composed of large modules separated by long dna repeat regions which obviously trigger recombination and modular shuffling.201222843857
ischaemic colitis associated with oral contraceptive and bisacodyl use.a woman with a history of hip replacement presented 3 days prior to revision of the hip with abdominal pain, diarrhoea and haematochezia. these symptoms began 6 h after she began taking bisacodyl in preparation for her upcoming surgery. she was on low-dose estradiol for hormone replacement therapy (hrt). subsequent colonoscopy and biopsies were consistent with acute colonic ischaemia (ci). she was treated with intravenous fluids and antibiotics and discharged and told to stop hrt and bisacodyl. ...201222843752
guillain-barré syndrome and anti-ganglioside antibodies: a clinician-scientist's journey.guillain-barré syndrome (gbs) is the most frequent cause of acute flaccid paralysis. having seen my first gbs patient in 1989, i have since then dedicated my time in research towards understanding the pathogenesis of gbs. along with several colleagues, we identified igg autoantibodies against ganglioside gm1 in two patients with gbs subsequent to campylobacter jejuni enteritis. we proceeded to demonstrate molecular mimicry between gm1 and bacterial lipo-oligosaccharide of c. jejuni isolated from ...201222850724
restricted gene flow among hospital subpopulations of enterococcus faecium.enterococcus faecium has recently emerged as an important multiresistant nosocomial pathogen. defining population structure in this species is required to provide insight into the existence, distribution, and dynamics of specific multiresistant or pathogenic lineages in particular environments, like the hospital. here, we probe the population structure of e. faecium using bayesian-based population genetic modeling implemented in bayesian analysis of population structure (baps) software. the anal ...201222807567
campylobacter epidemiology: a descriptive study reviewing 1 million cases in england and wales between 1989 and 2011.to review campylobacter cases in england and wales over 2 decades and examine the main factors/mechanisms driving the changing epidemiology.201222798256
estimating the relative roles of recombination and point mutation in the generation of single locus variants in campylobacter jejuni and campylobacter coli.single locus variants (slvs) are bacterial sequence types that differ at only one of the seven canonical multilocus sequence typing (mlst) loci. estimating the relative roles of recombination and point mutation in the generation of new alleles that lead to slvs is helpful in understanding how organisms evolve. the relative rates of recombination and mutation for campylobacter jejuni and campylobacter coli were estimated at seven different housekeeping loci from publically available mlst data. th ...201222767048
nutraceutical values of natural honey and its contribution to human health and wealth.the use of natural honey (nh) as a nutraceutical agent is associated with nutritional benefits and therapeutic promises. nh is widely accepted as food and medicine by all generations, traditions and civilizations, both ancient and modern. the nutritional profiles, including its use in infant and children feeding reported in different literatures as well as health indices and biomarkers observed by various researchers are illustrated in this manuscript. the review documents folk medicine, experim ...201222716101
detection of shiga toxin-producing escherichia coli by sandwich enzyme-linked immunosorbent assay using chicken egg yolk igy antibodies.enterohemorrhagic escherichia coli (ehec), a subset of shiga toxin producing e. coli (stec) is associated with a spectrum of diseases that includes diarrhea, hemorrhagic colitis and a life-threatening hemolytic-uremic syndrome (hus). regardless of serotype, shiga toxins (stx1 and/or stx2) are uniformly expressed by all ehec, and so exploitable targets for laboratory diagnosis of these pathogens. in this study, a sandwich elisa for determination of shiga toxin (stx) was developed using anti-stx2b ...201222919675
transmission of campylobacter coli in chicken embryos.campylobacter coli is an important species involved in human cases of enteritis, and chickens are carriers of the pathogen mainly in developing country. the current study aimed to evaluate the transmission of c. coli and its pathogenic effects in chicken embryos. breeder hens were inoculated intra-esophageally with c. coli isolated from chickens, and their eggs and embryos were analyzed for the presence of bacteria using real-time pcr and plate culture. the viability of embryos was verified. in ...201224031861
development and evaluation of a genus-specific, probe-based, internal-process-controlled real-time pcr assay for sensitive and specific detection of blastocystis spp.blastocystis is a common intestinal parasite of unsettled clinical significance, which is not easily detected by standard parasitological methods. the genus comprises at least 13 subtypes (sts) (which likely represent separate species), 9 of which have been found in humans. recent data indicate that at least one of the subtypes is associated with intestinal disease. a quantitative taqman 5' nuclease real-time pcr (taqman pcr) including an internal process control (ipc) was developed for the dete ...201222422846
selective pressure of antibiotic pollution on bacteria of importance to public health.many bacteria of clinical importance survive and may grow in different environments. antibiotic pollution may exert on them a selective pressure leading to an increase in the prevalence of resistance.201222571927
development of a novel genus-specific real-time pcr assay for detection and differentiation of bartonella species and genotypes.the genus bartonella includes numerous species with varied host associations, including several that infect humans. development of a molecular diagnostic method capable of detecting the diverse repertoire of bartonella species while maintaining genus specificity has been a challenge. we developed a novel real-time pcr assay targeting a 301-bp region of the ssra gene of bartonella and demonstrated specific amplification in over 30 bartonella species, subspecies, and strains. subsequent analysis o ...201222378904
characterization of the structurally diverse n-linked glycans of campylobacter species.the gram-negative bacterium campylobacter jejuni encodes an extensively characterized n-linked protein glycosylation system that modifies many surface proteins with a heptasaccharide glycan. in c. jejuni, the genes that encode the enzymes required for glycan biosynthesis and transfer to protein are located at a single pgl gene locus. similar loci are also present in the genome sequences of all other campylobacter species, although variations in gene content and organization are evident. in this ...201222389484
a gene-by-gene approach to bacterial population genomics: whole genome mlst of campylobacter.campylobacteriosis remains a major human public health problem world-wide. genetic analyses of campylobacter isolates, and particularly molecular epidemiology, have been central to the study of this disease, particularly the characterization of campylobacter genotypes isolated from human infection, farm animals, and retail food. these studies have demonstrated that campylobacter populations are highly structured, with distinct genotypes associated with particular wild or domestic animal sources, ...201224704917
xer recombinase and genome integrity in helicobacter pylori, a pathogen without topoisomerase iv.in the model organism e. coli, recombination mediated by the related xerc and xerd recombinases complexed with the ftsk translocase at specialized dif sites, resolves dimeric chromosomes into free monomers to allow efficient chromosome segregation at cell division. computational genome analysis of helicobacter pylori, a slow growing gastric pathogen, identified just one chromosomal xer gene (xerh) and its cognate dif site (difh). here we show that recombination between directly repeated difh sit ...201222511919
diversity in prokaryotic glycosylation: an archaeal-derived n-linked glycan contains legionaminic acid.vp4, the major structural protein of the haloarchaeal pleomorphic virus, hrpv-1, is glycosylated. to define the glycan structure attached to this protein, oligosaccharides released by β-elimination were analysed by mass spectrometry and nuclear magnetic resonance spectroscopy. such analyses showed that the major vp4-derived glycan is a pentasaccharide comprising glucose, glucuronic acid, mannose, sulphated glucuronic acid and a terminal 5-n-formyl-legionaminic acid residue. this is the first obs ...201222435790
longitudinal study of the persistence of antimicrobial-resistant campylobacter strains in distinct swine production systems on farms, at slaughter, and in the environment.the objectives of this study were to compare and characterize the prevalence of antimicrobial-resistant (ar) campylobacter in conventional and antimicrobial-free (abf) production systems on farms, at slaughter, and in the environment. fecal and environmental samples were collected from abf farms (pigs, 1,239; environment, 797) and conventional farms (pigs, 1,650; environment, 1,325). at slaughter, we collected samples from carcasses, including postevisceration swabs, postchill swabs, and mesente ...201222307299
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