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campylobacter bacteremia: a rare and under-reported event?bacteria belonging to the species campylobacter are the most common cause of bacterial diarrhoea in humans. the clinical phenotype associated with campylobacter infections ranges from asymptomatic conditions to severe colitis and bacteremia. in susceptible patients, campylobacter infections are associated with significant morbidity and mortality, with both host factors and bacterial factors being involved in the pathogenesis of bacteremia. in the host, age, gender and immune-compromising conditi ...201224611124
current concepts in laboratory testing to guide antimicrobial therapy.antimicrobial susceptibility testing (ast) is indicated for pathogens contributing to an infectious process that warrants antimicrobial therapy if susceptibility to antimicrobials cannot be predicted reliably based on knowledge of their identity. such tests are most frequently used when the etiologic agents are members of species capable of demonstrating resistance to commonly prescribed antibiotics. some organisms have predictable susceptibility to antimicrobial agents (ie, streptococcus pyogen ...201222386185
characterization of protein glycosylation in francisella tularensis subsp. holarctica: identification of a novel glycosylated lipoprotein required for virulence.fth_0069 is a previously uncharacterized strongly immunoreactive protein that has been proposed to be a novel virulence factor in francisella tularensis. here, the glycan structure modifying two c-terminal peptides of fth_0069 was identified utilizing high resolution, high mass accuracy mass spectrometry, combined with in-source cid tandem ms experiments. the glycan observed at m/z 1156 was determined to be a hexasaccharide, consisting of two hexoses, three n-acetylhexosamines, and an unknown mo ...201222361235
development and comparison of a real-time pcr assay for detection of dichelobacter nodosus with culturing and conventional pcr: harmonisation between three laboratories.ovine footrot is a contagious disease with worldwide occurrence in sheep. the main causative agent is the fastidious bacterium dichelobacter nodosus. in scandinavia, footrot was first diagnosed in sweden in 2004 and later also in norway and denmark. clinical examination of sheep feet is fundamental to diagnosis of footrot, but d. nodosus should also be detected to confirm the diagnosis. pcr-based detection using conventional pcr has been used at our institutes, but the method was laborious and t ...201222293440
the genome and proteome of a campylobacter coli bacteriophage vb_ccom-ibb_35 reveal unusual features.campylobacter is the leading cause of foodborne diseases worldwide. bacteriophages (phages) are naturally occurring predators of bacteria, ubiquitous in the environment, with high host specificity and thus considered an appealing option to control bacterial pathogens. nevertheless for an effective use of phages as antimicrobial agents, it is important to understand phage biology which renders crucial the analysis of phage genomes and proteomes. the lack of sequence data from campylobacter phages ...201222284308
Comparative Genomics of Helicobacter pylori and the human-derived Helicobacter bizzozeronii CIII-1 strain reveal the molecular basis of the zoonotic nature of non-pylori gastric Helicobacter infections in humans.ABSTRACT:201122039924
pan-european monitoring of susceptibility to human-use antimicrobial agents in enteric bacteria isolated from healthy food-producing animals.objectives: to determine the antimicrobial susceptibility of escherichia coli, salmonella, campylobacter and enterococcus from cattle, pigs and chickens across the european union (eu) using uniform methodology. methods: intestinal samples (1624) were taken at slaughter across five eu countries. bacteria were isolated in national laboratories, whilst mics were determined in a central laboratory for key antimicrobials used in human medicine. clinical resistance was based on clsi breakpoints and de ...201122210758
Prevalence and antimicrobial susceptibility of major foodborne pathogens in imported seafood.Seafood is a leading commodity implicated in foodborne disease outbreaks in the United States. Seafood importation rose dramatically in the past 3 decades and now contributes to more than 80% of the total U.S. seafood supply. However, limited data are available on the microbiological safety of imported seafood. In this study, we obtained a total of 171 salmon, shrimp, and tilapia samples imported from 12 countries in three retail stores in Baton Rouge, LA. The total microbial population and the ...201121902913
Development of a rapid and sensitive method combining a cellulose ester microfilter and a real-time qPCR assay to detect Campylobacter jejuni and Campylobacter coli in 20 liters of drinking water or low turbidity waters.Investigation of Campylobacter jejuni and Campylobacter coli in samples of drinking water suspected of being at the origin of outbreak very often leads to negative results. One of the reasons for this failure is the small volume of water typically used for detecting these pathogens (10 to 1000 mL). Efficiency of three microfilters and different elution procedures were determined using real-time qPCR to propose a procedure allowing detection of Campylobacter in 20 L drinking water or low turbidit ...201122138985
high prevalence of intestinal carriage of campylobacter coli in patients with primary antibody deficiencies: a silent infection that could shift to a life-threatening condition. 201121358549
comparison of cape town and skirrow's campylobacter isolation protocols in humans and broilers in morogoro, tanzania.comparison of cape town and skirrow's protocols used in isolation of campylobacter in humans and broilers was carried out in a cross-sectional study in morogoro, tanzania. a total of 176 and 158 human stool and broiler intestinal samples were collected, respectively. while human stool samples were collected from selected health centers, broiler intestinal samples were obtained from selected farms and chicken markets. samples were inoculated and cultured in duplicate using two protocols and preva ...201121359592
pathogenic potential of campylobacter ureolyticus.the recent detection and isolation of the aflagellate campylobacter ureolyticus (previously known as bacteroides ureolyticus) from intestinal biopsy specimens and fecal samples of children with newly diagnosed crohn's disease led us to investigate the pathogenic potential of this bacterium. adherence and gentamicin protection assays were employed to quantify the levels of adherence to and invasion into host cells. c. ureolyticus unswcd was able to adhere to the caco-2 intestinal epithelial cell ...201122124656
applications of pcr (real-time and masstag) and enzyme-linked immunosorbent assay in diagnosis of respiratory infections and diarrheal illness among deployed u.s. military personnel during exercise balikatan 2009, philippines.laboratory-based surveillance for diarrheal and respiratory illness was conducted at the 2009 republic of the philippines-united states balikatan exercise to determine the presence of specific pathogens endemic in the locations where the military exercises were conducted. ten stool and 6 respiratory specimens were obtained from individuals meeting case definitions for diarrhea or respiratory illness. stool specimens were frozen in dry ice and remotely tested using enzyme-linked immunosorbent ass ...201122128641
analysis of caga in helicobacter pylori strains from colombian populations with contrasting gastric cancer risk reveals a biomarker for disease severity.helicobacter pylori infection is a risk factor for the development of gastric cancer, and the bacterial oncoprotein caga contributes to gastric carcinogenesis.201121859954
whole-genome comparison of two campylobacter jejuni isolates of the same sequence type reveals multiple loci of different ancestral lineage.campylobacter jejuni st-474 is the most important human enteric pathogen in new zealand, and yet this genotype is rarely found elsewhere in the world. insight into the evolution of this organism was gained by a whole genome comparison of two st-474, flaa svr-14 isolates and other available c. jejuni isolates and genomes. the two isolates were collected from different sources, human (h22082) and retail poultry (p110b), at the same time and from the same geographical location. solexa sequencing of ...201122096527
pulsed-field gel electrophoresis analysis of more than one clinical isolate of campylobacter spp. from each of 49 patients in new zealand.pulsed-field gel electrophoresis (pfge) analysis demonstrated that while 76% of patients had only one genotype of campylobacter, 10% carried two different but related genotypes (dice coefficients > 0.78), and 14% carried at least two unrelated genotypes (dice coefficients < 0.65). this supports the clustering of campylobacter isolates with similar pfge patterns, highlights the need to analyze multiple isolates from both sources and patients, and confirms that caution should be exercised before e ...201122116155
does human bocavirus infection depend on helper viruses? a challenging case report.a case of severe diarrhoea associated with synergistic human bocavirus type 1 (hbov) and human herpes virus type 6 (hhv6) is reported. the case supports the hypotheses that hbov infection under clinical conditions may depend on helper viruses, or that hbov replicates by a mechanism that is atypical for parvoviruses, or that hbov infection can be specifically treated with cidofovir.201121871135
effects of polyphosphate additives on the ph of processed chicken exudates and the survival of campylobacter.campylobacter spp. are nutritionally fastidious organisms that are sensitive to normal atmospheric oxygen levels and lack homologues of common cold shock genes. at first glance, these bacteria seem ill equipped to persist within food products under processing and storage conditions; however, they survive in numbers sufficient to cause the largest number of foodborne bacterial disease annually. a mechanism proposed to play a role in campylobacter survival is the addition of polyphosphate-contain ...201122004823
a model for the effect of homologous recombination on microbial diversification.the effect of homologous recombination (hr) on the evolution of microbial genomes remains contentious as competing hypotheses seek to explain the evolutionary dynamics of microbial species. evidence for hr between microbial genomes is widespread, and this process has been proposed to act as a cohesive force that can constrain the diversification of microbial lineages. we seek to characterize the evolutionary dynamics of sympatric populations to explore the impact of hr on microbial speciation. w ...201122071790
fate and survival of campylobacter coli in swine manure at various temperatures.campylobacter coli is the most common campylobacter species found in pig (95%), but the ability of this bacterium to survive in swine manure as well as the potential for causing human illness are poorly understood. we present here laboratory-scale experiments to investigate the effect of temperature on the survival of c. coli in spiked swine manure samples at temperatures from 4 to 52°c. the survival of c. coli during storage for 30 days was studied by three different methods: bacterial culture ...201122207868
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
introgression in the genus campylobacter: generation and spread of mosaic alleles.horizontal genetic exchange strongly influences the evolution of many bacteria, substantially contributing to difficulties in defining their position in taxonomic groups. in particular, how clusters of related bacterial genotypes - currently classified as microbiological species - evolve and are maintained remains controversial. the nature and magnitude of gene exchange between two closely related (approx. 15 % nucleotide divergence) microbiologically defined species, campylobacter jejuni and ca ...201121212120
detection, isolation, and characterization of helicobacter species from the gastrointestinal tract of the brushtail possum.the presence of helicobacter species in australian marsupials was examined systematically using microscopy, culture, and pcr in different regions of the gastrointestinal tract (git) and in the liver of brushtail possums (btps) (trichosurus vulpecula), a common australian marsupial that feeds on eucalyptus leaves. the spatial distribution of helicobacter species in the git sections also was examined microscopically in silver-stained sections and by fluorescent in situ hybridization (fish) using a ...201121216901
arcobacter population dynamics in pigs on farrow-to-finish farms.healthy pigs are an important reservoir for the emerging human pathogen arcobacter which can result in contamination of porcine carcasses and pork and the spread of arcobacters into the environment. up to now, the excretion of arcobacters by pigs has been studied, but information about the transmission routes in fattening pigs is lacking. the present study aimed to elucidate the arcobacter population dynamics in pigs during the fattening period on four farrow-to-finish farms. on each farm, 30 cl ...201121216902
in vivo recognition of the feca3 target promoter by helicobacter pylori nikr.in helicobacter pylori, the transcriptional regulator hpnikr represses transcription of the feca3 gene by binding to two adjacent operators spanning a region of almost 80 nucleotides along the feca3 promoter in a nickel-dependent manner. by employing hydroxyl radical footprinting, we mapped the protected nucleotides within each operator. three short sequences rich in a and t nucleotides were identified within each operator, comprising just 24 bases for both operators, with 4 or 5 protected bases ...201121216998
a novel immunity system for bacterial nucleic acid degrading toxins and its recruitment in various eukaryotic and dna viral systems.the use of nucleases as toxins for defense, offense or addiction of selfish elements is widely encountered across all life forms. using sensitive sequence profile analysis methods, we characterize a novel superfamily (the sukh superfamily) that unites a diverse group of proteins including smi1/knr4, pgs2, fbxo3, skip16, syd, herpesviral us22, irs1 and trs1, and their bacterial homologs. using contextual analysis we present evidence that the bacterial members of this superfamily are potential imm ...201121306995
prevalence of putative virulence markers in campylobacter jejuni and campylobacter coli isolated from hospitalized children, raw chicken, and raw beef in tehran, iran.the incidence of the virulence-associated genes cdta, cdtb, cdtc, cadf, dnaj, racr, and plda has been investigated in campylobacter jejuni and campylobacter coli collected from raw chicken and beef from retailers in tehran, iran, and from hospitalized children (age, =14 years) suffering from diarrhea. campylobacter spp. were collectively identified by morphological and biochemical methods. campylobacter jejuni and c. coli were discriminated from other campylobacter spp. by amplification of a spe ...201121326356
a charcoal- and blood-free enrichment broth for isolation and pcr detection of campylobacter jejuni and campylobacter coli in chicken.the microaerophilic nature of campylobacter and its requirement of ~5% o(2) for growth have complicated its recovery from foods. the addition to the enrichment media of oxygen quenchers such as charcoal or blood could interfere with pcr for its detection. in this study, a two-step simple aerobic method for campylobacter detection is proposed. a modification of the tran blood-free enrichment broth (bfeb), in which charcoal was excluded from the medium (m-bfeb), was compared with the original form ...201121333141
detection and genotypic differentiation of campylobacter jejuni and campylobacter coli strains from laying hens by multiplex pcr and fla-typing.in total, 26 campylobacter (c.) strains, isolated from liver, spleen, caecal or jejunal content of laying hens from different flocks were examined. in these flocks a drop in egg production, an increasing mortality and livers with whitish-grey lesions as post-mortem finding were observed. suspected campylobacter colonies were differentiated using a modified m-pcr in 13 campylobacter jejuni and 13 campylobacter coli strains. all isolates were characterised by typing of the flaa and flab gene each ...201121349563
antimicrobial resistance in campylobacter coli isolated from pigs in two provinces of china.the aim of this study was to determine the prevalence, antimicrobial resistance and molecular epidemiology of campylobacter coli isolated from swine in china. a total of 190 c. coli isolates obtained from two slaughter houses and ten conventional pig farms in shandong (sd, n=95) and ningxia (nx, n=95) provinces were tested for their susceptibility to 14 antimicrobials. a high prevalence (>95%) of ciprofloxacin and tetracycline-resistant strains was observed in both sd and nx. the erythromycin an ...201121349598
prevalence and antimicrobial susceptibility of campylobacter in broiler flocks in japan.campylobacter was isolated from 67 (47.2%) of 142 broiler flocks between september 2009 and february 2010. the prevalence of campylobacter in broiler flocks was significantly lower during january and february than it was from september to december. campylobacter colonization was more common in flocks that were not provided with a disinfected water supply, which was consistent with the findings of a previous study. the prevalence of antimicrobial drug-resistant campylobacter spp. was investigated ...201122103704
A Nationwide Study of Campylobacter jejuni and Campylobacter coli bacteremia in Finland over a 10-year period, 1998-2007, with special reference to clinical characteristics and antimicrobial susceptibility.Campylobacter bacteremia is an uncommon condition, usually diagnosed in elderly and immunocompromised patients.201121921217
genetic organisation, mobility and predicted functions of genes on integrated, mobile genetic elements in sequenced strains of clostridium difficile.clostridium difficile is the leading cause of hospital-associated diarrhoea in the us and europe. recently the incidence of c. difficile-associated disease has risen dramatically and concomitantly with the emergence of 'hypervirulent' strains associated with more severe disease and increased mortality. c. difficile contains numerous mobile genetic elements, resulting in the potential for a highly plastic genome. in the first sequenced strain, 630, there is one proven conjugative transposon (ctn) ...201121876735
Ribosomal mutations as the main cause of macrolide resistance in Campylobacter jejuni and Campylobacter coli.The aim of this study was to examine macrolide resistance mutations in Campylobacter species. In 76 strains studied, point mutation A to G at position 2059 of the 23S rRNA gene was detected in 30 of the 33 erythromycin-resistant strains. An amino acid insertion in the ribosomal protein L22 was found in one resistant strain without a 23S rRNA mutation. The A2059G mutation is the main cause of macrolide resistance in Campylobacter species.201121911571
helicobacter pylori exploits a unique repertoire of type iv secretion system components for pilus assembly at the bacteria-host cell interface.colonization of the human stomach by helicobacter pylori is an important risk factor for development of gastric cancer. the h. pylori cag pathogenicity island (cag pai) encodes components of a type iv secretion system (t4ss) that translocates the bacterial oncoprotein caga into gastric epithelial cells, and cagl is a specialized component of the cag t4ss that binds the host receptor α5β1 integrin. here, we utilized a mass spectrometry-based approach to reveal co-purification of cagl, cagi (anoth ...201121909278
a comprehensive evaluation of colonic mucosal isolates of sutterella wadsworthensis from inflammatory bowel disease.inflammatory bowel disease (ibd) arises in genetically susceptible individuals as a result of an unidentified environmental trigger, possibly a hitherto unknown bacterial pathogen. twenty-six clinical isolates of sutterella wadsworthensis were obtained from 134 adults and 61 pediatric patients undergoing colonoscopy, of whom 69 and 29 respectively had ibd. s. wadsworthensis was initially more frequently isolated from ibd subjects, hence this comprehensive study was undertaken to elucidate its ro ...201122073125
Improvement of Modified Charcoal-Cefoperazone-Deoxycholate Agar by Supplementation with a High Concentration of Polymyxin B for the Detection of Campylobacter jejuni and C. coli in Chicken Carcass Rinse.Modified charcoal-cefoperazone-deoxycholate agar (mCCDA) was improved by supplementation with a high concentration of polymyxin B. The ability of the supplemented medium to isolate Campylobacter jejuni and C. coli from chicken carcass rinse was compared to that of Campy-Cefex agar and mCCDA. Modification of mCCDA with increased polymyxin B yielded significantly (p < 0.05) better isolation rate and selectivity than those achieved on using Campy-Cefex agar and mCCDA.201122210208
genotypes and antibiotic resistance of campylobacter coli in fattening pigs.campylobacter coli is a food-borne zoonotic pathogen causing human gastroenteritis worldwide. the organism is a commensal in the intestine of many food production animals including fattening pigs. the role of the pig as a potential reservoir for c. coli affecting human either directly or via poultry has hardly been investigated and genetic characterization of porcine strains is needed to address this question. for this aim multilocus sequence typing (mlst) and flab typing was applied to 256 c. c ...201121899961
prevalence of campylobacter species in adult crohn's disease and the preferential colonization sites of campylobacter species in the human intestine.crohn's disease (cd) and ulcerative colitis (uc) are the two major forms of inflammatory bowel disease (ibd). a high prevalence of campylobacter concisus was previously detected in paediatric cd and adult uc. currently, the prevalence of c. concisus in adult cd and the preferential colonization sites of campylobacter species in the human intestine are unknown. in this study, we examined the prevalence of campylobacter species in biopsies collected from multiple anatomic sites of adult patients w ...201121966525
campylobacter jejuni infection and its virulence associated genes among children with moderate to severe diarrhea attended at emergency rooms in northeastern brazil.campylobacter is an important cause of foodborne gastroenteritis. we determined the occurrence of campylobacter sp. - using culture-based methods - and c. jejuni, c. coli and some virulence associated genes (vag) - using pcr - among children aged ≤ 14 years attended at emergency rooms in northeastern brazil because of diarrhea. genomic dna was extracted directly from stool samples collected from 366 children. a survey form regarding clinical parameters was applied to caretakers. c. jejuni was de ...201122174372
closely related campylobacter jejuni strains from different sources reveal a generalist rather than a specialist lifestyle.abstract: background: campylobacter jejuni and campylobacter coli are human intestinal pathogens of global importance. zoonotic transmission from livestock animals or animal-derived food is the likely cause for most of these infections. however, little is known about their general and host-specific mechanisms of colonization, or virulence and pathogenicity factors. in certain hosts, campylobacter species colonize persistently and do not cause disease, while they cause acute intestinal disease i ...201122122991
helicobacter pylori relies primarily on the purine salvage pathway for purine nucleotide biosynthesis.helicobacter pylori is a chronic colonizer of the gastric epithelium and plays a major role in the development of gastritis, peptic ulcer disease, and gastric cancer. in its co-evolution with humans, a streamlining of the h. pylori genome has resulted in a significant reduction in metabolic pathways, one being purine nucleotide biosynthesis. bioinformatic analysis revealed that h. pylori lacks the enzymatic machinery for de novo production of inosine monophosphate (imp), the first purine nucleot ...201122194455
fate of pathogens in a simulated bioreduction system for livestock carcasses.the eu animal by-products regulations generated the need for novel methods of storage and disposal of dead livestock. bioreduction prior to rendering or incineration has been proposed as a practical and potentially cost-effective method; however, its biosecurity characteristics need to be elucidated. to address this, salmonella enterica (serovars senftenberg and poona), enterococcus faecalis, campylobacter jejuni, campylobacter coli and a lux-marked strain of escherichia coli o157 were inoculate ...201122119516
identification of lactobacilli residing in chicken ceca with antagonism against campylobacter.bacteriocins produced by lactobacillus salivarius have been recently recognized as a natural means to control campylobacter and salmonella in live poultry. this finding is of relevance since campylobacter jejuni and campylobacter coli are the predominant species isolated from poultry that are associated with human campylobacteriosis. in the present work, lactic acid bacteria (lab) isolated from the cecum of twenty tunisian chickens were identified and those isolates with antagonism against campy ...201122069154
campylobacter spp. as a foodborne pathogen: a review.campylobacter is well recognized as the leading cause of bacterial foodborne diarrheal disease worldwide. symptoms can range from mild to serious infections of the children and the elderly and permanent neurological symptoms. the organism is a cytochrome oxidase positive, microaerophilic, curved gram-negative rod exhibiting corkscrew motility and is carried in the intestine of many wild and domestic animals, particularly avian species including poultry. intestinal colonization results in healthy ...201121991264
impaired fitness and transmission of macrolide-resistant campylobacter jejuni in its natural host.campylobacter jejuni is a major zoonotic pathogen transmitted to humans via the food chain and is prevalent in chickens, a natural reservoir for this pathogenic organism. due to the importance of macrolide antibiotics in clinical therapy of human campylobacteriosis, development of macrolide resistance in campylobacter has become a concern for public health. to facilitate the control of macrolide-resistant campylobacter, it is necessary to understand if macrolide resistance affects the fitness an ...201122183170
Genome and proteome of Campylobacter jejuni bacteriophage NCTC 12673.Campylobacter jejuni continues to be the leading cause of bacterial food-borne illness worldwide, so improvements to current methods used for bacterial detection and disease prevention are needed. We describe here the genome and proteome of C. jejuni bacteriophage NCTC 12673 and the exploitation of its receptor-binding protein for specific bacterial detection. Remarkably, the 135-kb Myoviridae genome of NCTC 12673 differs greatly from any other proteobacterial phage genome described (including C ...201121965409
emerging dynamics of human campylobacteriosis in southern ireland.infections with campylobacter spp. pose a significant health burden worldwide. the significance of campylobacter jejuni/campylobacter coli infection is well appreciated but the contribution of non-c. jejuni/c. coli spp. to human gastroenteritis is largely unknown. in this study, we employed a two-tiered molecular study on 7194 patient faecal samples received by the microbiology department in cork university hospital during 2009. the first step, using entericbio(®) (serosep), a multiplex pcr syst ...201122077228
campylobacter populations in wild and domesticated mallard ducks (anas platyrhynchos).identifying the campylobacter genotypes that colonize farmed and wild ducks will help to assess the proportion of human disease that is potentially attributable to the consumption of duck meat and environmental exposure to duck faeces. comparison of temporally and geographically matched farmed and wild ducks showed that they had different campylobacter populations in terms of: (i) prevalence, (ii) campylobacter species and (iii) diversity of genotypes. furthermore, 92.4% of campylobacter isolate ...201122164198
[antimicrobial sensitivity of hippurate-negative campylobacter and helicobacter pullorum strains isolated from patients with diarrhea].c. jejuni as well as some hippurate-negative campylobacter species and related diarrheagenic organisms, are the leading cause of gastroenteritis in our environment all throughout the year. the aim of the present study was to determine the sensitivity of hippurate-negative campylobacter and helicobacter pullorum strains isolated from the stools of patients with diarrhea. we tested 39 campylobacter coli, two c. lari and five helicobacter pullorum strains identified by mass spectrometry analysis. t ...201122173192
extracts of edible and medicinal plants in inhibition of growth, adherence, and cytotoxin production of campylobacter jejuni and campylobacter coli.campylobacter spp. is recognized as one of the most common cause of food-borne bacterial gastroenteritis in humans. campylobacter infection causes campylobacteriosis, which can range from asymptomatic to dysentery-type illnesses with severe complications, such as guillian-barre syndrome. epidemiological studies have revealed that consumption of poultry products is an important risk factor of this disease. adherence and cytotoxic activity of the bacteria to host mucosal surfaces have been propose ...201122417513
evaluation of novel agars for the enumeration of campylobacter spp. in poultry retail samples.the purpose of this study was to examine the performance of novel agars for the identification and enumeration of campylobacter species. the analytical sensitivity and specificity of campylobacter selective agar (casa), brilliance campycount agar (bcca) and campyfoodidagar (cfa) for 84 campylobacter spp. isolates and 50 non-campylobacter spp. isolates from 37 distinct genera were of 100% sensitivity, with a 98% specificity for bcca and cfa, and a 100% specificity for casa. the application of the ...201122226753
the zinc-ribbon domain of helicobacter pylori hp0958: requirement for rpon accumulation and possible roles of homologs in other bacteria.helicobacter pylori hp0958 protein (flgz) prevents the rapid turnover of rpon (σ(54)), a transcription factor required for expression of several flagellar genes in h. pylori. flgz possesses a zinc-ribbon domain (duf164) that contains two conserved cxxc motifs which coordinate a zinc ion and is thought to interact with nucleic acids or proteins. two conserved cysteine residues in flgz (cys-202 and cys-223) were replaced with serine to assess their significance in flgz function. after confirming t ...201122408721
welcome to microbial informatics and experimentation. 201122587655
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
novel glycosylation sites localized in campylobacter jejuni flagellin flaa by liquid chromatography electron capture dissociation tandem mass spectrometry.glycosylation of flagellin in campylobacter jejuni is essential for motility and virulence. it is well-known that flagellin from c. jejuni 81-176 is glycosylated by pseudaminic acid and its acetamidino derivative, and that campylobactor coli vc167 flagellin is glycosylated by legionaminic acid and its derivatives. recently, it was shown, by use of a metabolomics approach, that c. jejuni 11168 is glycosylated by dimethyl glyceric acid derivatives of pseudaminic acid, but the sites of glycosylatio ...201121158479
novel glycosylation sites localized in campylobacter jejuni flagellin flaa by liquid chromatography electron capture dissociation tandem mass spectrometry.glycosylation of flagellin in campylobacter jejuni is essential for motility and virulence. it is well-known that flagellin from c. jejuni 81-176 is glycosylated by pseudaminic acid and its acetamidino derivative, and that campylobactor coli vc167 flagellin is glycosylated by legionaminic acid and its derivatives. recently, it was shown, by use of a metabolomics approach, that c. jejuni 11168 is glycosylated by dimethyl glyceric acid derivatives of pseudaminic acid, but the sites of glycosylatio ...201121158479
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
change is good: variations in common biological mechanisms in the epsilonproteobacterial genera campylobacter and helicobacter.microbial evolution and subsequent species diversification enable bacterial organisms to perform common biological processes by a variety of means. the epsilonproteobacteria are a diverse class of prokaryotes that thrive in diverse habitats. many of these environmental niches are labeled as extreme, whereas other niches include various sites within human, animal, and insect hosts. some epsilonproteobacteria, such as campylobacter jejuni and helicobacter pylori, are common pathogens of humans tha ...201121372321
related antimicrobial resistance genes detected in different bacterial species co-isolated from swine fecal samples.a potential factor leading to the spread of antimicrobial resistance (ar) in bacteria is the horizontal transfer of resistance genes between bacteria in animals or their environment. to investigate this, swine fecal samples were collected on-farm and cultured for escherichia coli, salmonella enterica, campylobacter spp., and enterococcus spp. which are all commonly found in swine. forty-nine of the samples from which all four bacteria were recovered were selected yielding a total of 196 isolates ...201121385089
fitness cost of fluoroquinolone resistance in campylobacter coli and campylobacter jejuni.in this study, the fitness cost of fluoroquinolone resistance was evaluated in vitro, on food matrices, and in vivo, using campylobacter coli and campylobacter jejuni in vitro selected mutants. in vitro, the growth rate of the susceptible (wild type) and resistant (mutant) strains did not differ when cultured separately. however, by conducting sequential passages of mixed cultures, the ratio of the resistant mutant to the susceptible strain decreased for c. coli but not for c. jejuni. when the w ...201121388301
automated identification of medically important bacteria by 16s rrna gene sequencing using a novel comprehensive database, 16spathdb.despite the increasing use of 16s rrna gene sequencing, interpretation of 16s rrna gene sequence results is one of the most difficult problems faced by clinical microbiologists and technicians. to overcome the problems we encountered in the existing databases during 16s rrna gene sequence interpretation, we built a comprehensive database, 16spathdb (http://147.8.74.24/16spathdb) based on the 16s rrna gene sequences of all medically important bacteria listed in the manual of clinical microbiology ...201121389154
longitudinal on-farm study of the development of antimicrobial resistance in campylobacter coli from pigs before and after danofloxacin and tylosin treatments.effects of danofloxacin or consecutive fluoroquinolone and macrolide treatments on resistance development in campylobacter have remained uncharacterised. therefore we analysed the development of resistance in porcine campylobacter coli before and after danofloxacin and tylosin treatments at a farrowing farm. danofloxacin-treated (n=12, group a) and control pigs (n=15, group b) were subsequently treated with tylosin and sampled longitudinally. c. coli were isolated and susceptibilities to ciprofl ...201121397412
comparative genotypic and pathogenic examination of campylobacter concisus isolates from diarrheic and non-diarrheic humans.campylobacter concisus is an emerging enteric pathogen, yet it is commonly isolated from feces and the oral cavities of healthy individuals. this genetically complex species is comprised of several distinct genomospecies which may vary in pathogenic potential.201121406111
eleutherine americana: a candidate for the control of campylobacter species.the antibacterial activity of ethanolic extracts of selected thai medicinal plants (rhodomyrtus tomentosa (aiton) hassk., quercus infectoria g. olivier, and eleutherine americana merr.) against campylobacter spp. was investigated. sixty-five campylobacter, including 39 isolates from humans and 26 isolates from chicken samples, were tested. reference campylobacter spp. that are commonly encountered in gastroenteritis were included. the ethanolic extract of e. americana demonstrated good antibacte ...201121406364
etiology of diarrhea in young children and patterns of antibiotic resistance in cambodia.little is known about diarrhea etiology and antibiotic resistance in developing countries where diarrhea is a major public health problem.201121412204
campylobacter jejuni, campylobacter coli, and cytolethal distending toxin (cdt) genes in common teals (anas crecca).to evaluate the presence of campylobacter spp. and related cdt genes, cloacal swabs were collected from 70 common teals (anas crecca) and analyzed by culture methods and polymerase chain reaction. in addition, c. jejuni were examined also for the presence of wlan gene. this is believed to be the first report of campylobacter spp. in common teal and our results confirm the very common occurrence of c. jejuni (n=40) and c. coli (n=13) in waterfowls. furthermore, the cdt genes were frequently prese ...201121450419
influence of season and geography on campylobacter jejuni and c. coli subtypes in housed broiler flocks reared in great britain.geographical and seasonal variation in the incidence and prevalence of campylobacter jejuni and c. coli in housed broiler flocks reared in great britain in 2004 to 2006 was investigated in this study. ceca (30) from 797 flocks, not subject to prior partial depopulation and reared on 211 farms, were examined individually for the presence of campylobacter spp. the best-fitting climatic factors explained approximately 46% of the prevalence of campylobacter-colonized flocks at slaughter and consiste ...201121460110
diarrheagenic pathogens in polymicrobial infections.during systematic active surveillance of the causes of diarrhea in patients admitted to the infectious diseases and beliaghata general hospital in kolkata, india, we looked for 26 known gastrointestinal pathogens in fecal samples from 2,748 patients. samples from about one-third (29%) of the patients contained multiple pathogens. polymicrobial infections frequently contained vibrio cholerae o1 and rotavirus. when these agents were present, some co-infecting agents were found significantly less o ...201121470448
efficacy of uv light treatment for the microbiological decontamination of chicken, associated packaging, and contact surfaces.uv light was investigated for the decontamination of raw chicken, associated packaging, and contact surfaces. the uv susceptibilities of a number of campylobacter isolates (seven campylobacter jejuni isolates and three campylobacter coli isolates), escherichia coli atcc 25922, and salmonella enterica serovar enteritidis atcc 10376 in liquid media were also investigated. from an initial level of 7 log cfu/ml, no viable campylobacter cells were detected following exposure to the most intense uv do ...201121477470
antimicrobial resistance and molecular subtyping of campylobacter jejuni and campylobacter coli from retail meats.campylobacter isolates (n = 297; 202 c. jejuni and 95 c. coli isolates) recovered from 2,513 retail meat samples (chicken breasts, ground turkey, ground beef, and pork chops) were examined for antimicrobial susceptibility. the isolates were further analyzed for genetic relatedness by pulsed-field gel electrophoresis (pfge) using smai and kpni restriction enzymes, and a subset of isolates (n = 174) were subtyped by multilocus sequence typing (mlst). the resistance most frequently observed was tha ...201121477476
l-fucose utilization provides campylobacter jejuni with a competitive advantage.campylobacter jejuni is a prevalent gastrointestinal pathogen in humans and a common commensal of poultry. when colonizing its hosts, c. jejuni comes into contact with intestinal carbohydrates, including l-fucose, released from mucin glycoproteins. several strains of c. jejuni possess a genomic island (cj0480c-cj0490) that is up-regulated in the presence of both l-fucose and mucin and allows for the utilization of l-fucose as a substrate for growth. strains possessing this genomic island show in ...201121482772
occurrence of thermotolerant campylobacter spp. on eggshells: a missing link for food-borne infections?we analyzed the prevalence of thermotolerant campylobacter spp. compared that of to salmonella spp. in raw yolk and on eggshells. a total of 2,710 eggs were investigated for each bacterium. viable bacteria were found in 4.1% (campylobacter spp.) and 1.1% (salmonella spp.) of the eggshell samples, whereas the egg yolk samples were negative for both bacteria.201121498761
campylobacter jejuni, campylobacter coli, and cytolethal distending toxin genes in laying hens.as no data are available on the prevalence of cytolethal distending toxin (cdt) genes carried by campylobacter spp. in laying hens, this study was conducted with the aim to evaluate the prevalence of both campylobacter spp. and cdt genes in 1680 laying hens from four different farms. the samples were analyzed by culture methods and by polymerase chain reaction. campylobacter spp. were isolated from 1097/1680 cloacal swabs. among the isolates, 913 were identified as campylobacter jejuni whereas 3 ...201121500644
prevalence and risk factors for campylobacter spp. in chicken broiler flocks in reunion island (indian ocean).our objectives were to determine campylobacter prevalence in broiler chicken flocks in reunion island and to define specific practices associated with the presence of campylobacter spp. infection in reunionese broiler flocks. fifty broiler flocks were studied in reunion island from may 2007 to february 2009. a questionnaire was submitted to the farmers and samples of fresh droppings were collected to assess the flock's campylobacter status. fifty four percent of the flocks were infected by campy ...201121511349
differentiation of campylobacter species by surface-enhanced laser desorption/ionization-time-of-flight mass spectrometry.abstract the genus campylobacter contains several, widespread pathogens causing food-borne diseases of zoonotic nature in humans. in case of outbreaks, the differentiation of closely related campylobacter is essential for epidemiological studies, which investigate the routes of geographical spread and ways of transmission. recent advances in mass spectrometry (ms) have shown that matrix-assisted laser desorption/ionization-time-of-flight (maldi-tof) ms is a valuable tool for speciation of bacter ...201121524195
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
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