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revision of campylobacter, helicobacter, and wolinella taxonomy: emendation of generic descriptions and proposal of arcobacter gen. nov.hybridization experiments were carried out between dnas from more than 70 strains of campylobacter spp. and related taxa and either 3h-labeled 23s rrnas from reference strains belonging to campylobacter fetus, campylobacter concisus, campylobacter sputorum, campylobacter coli, and campylobacter nitrofigilis, an unnamed campylobacter sp. strain, and a wolinella succinogenes strain or 3h- or 14c-labeled 23s rrnas from 13 gram-negative reference strains. an immunotyping analysis of 130 antigens ver ...19911704793
atypical structure of the 23s ribosomal rna molecule in certain oral bacteria.ribosomal rna (rrna) isolated from wolinella recta and seven related bacteria was examined by agarose gel electrophoresis. the 23s rrna molecule could not be detected in w. recta, wolinella curva, bacteroides gracilis, or bacteroides ureolyticus. in place of the 23s molecule, there were three smaller molecules of approximately 1700, 650, and 600 bases designated 23s alpha, 23s beta, and 23s delta, respectively. an intact 23s rrna molecule could be isolated from wolinella succinogenes, campylobac ...19911710629
multicenter evaluation of tetracycline fiber therapy. iii. microbiological response.in a multicenter study of the effects of tetracycline (tc) fiber therapy, subgingival plaque samples were tested for 6 probable periodontal pathogens by dna probe analysis. levels of actinobacillus actinomycetemcomitans, eikenella corrodens, fusobacterium nucleatum, porphyromonas (bacteroides) gingivalis, prevotella intermedia (bacteroides intermedius), and wolinella recta were quantitatively determined in samples taken at baseline, and immediately after tc fiber removal, control fiber removal, ...19911832457
wolinella recta, wolinella curva, bacteroides ureolyticus, and bacteroides gracilis are microaerophiles, not anaerobes.although the nonfermentative, asaccharolytic, putative anaerobes wolinella curva, wolinella recta, bacteroides ureolyticus, and bacteroides gracilis are phylogenetically related to the true campylobacters, the type strains of these species exhibited o2-dependent microaerophilic growth in brucella broth and on brucella agar. the optimum o2 levels for growth of these strains ranged from 4 to 14% in brucella broth and from 2 to 8% on brucella agar, when h2 was provided as the electron donor. no gro ...19911854636
multivariate analyses of cellular fatty acids in bacteroides, prevotella, porphyromonas, wolinella, and campylobacter spp.the genera bacteroides, wolinella, and campylobacter contain several similar species that require taxonomic revision. fatty acid profiles of whole bacterial cells have proven useful for taxonomy. in this study, cellular fatty acids from bacteroides, prevotella, porphyromonas, wolinella, and campylobacter spp. were identified and quantitated by gas chromatography and gas chromatography-mass spectrometry, and the data were subjected to principal component analyses. bacteroides fragilis, the type s ...19911993755
analysis of cell surface antigens of campylobacter rectus.campylobacter rectus is one of the predominant bacteria in the lesions of human periodontitis. the surface antigens of the bacterium contain several components which may play significant roles in colonization and pathogenesis. a high-molecular-weight protein was selectively isolated from the cell surface of c. rectus by acid extraction and purified by deae sepharose. sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that the extracted protein was 150 kda. the protein was ...19921303324
cytochrome composition and oxygen-dependent respiration-driven proton translocation in wolinella curva, wolinella recta, bacteroides ureolyticus, and bacteroides gracilis.the membrane fractions of the microaerobically grown type strains of wolinella curva, wolinella recta, bacteroides ureolyticus, and bacteroides gracilis contained membrane-bound cytochrome b, cytochrome c, and co-binding cytochrome c. soluble cytochrome c and co-binding cytochrome c were also present. although b. gracilis is oxidase negative, it possessed cytochrome c. with h2 or formate as the electron donor, proton efflux from anaerobic cells occurred upon addition of a pulse of oxygen. with f ...19921325865
campylobacter showae sp. nov., isolated from the human oral cavity.nine campylobacter-like strains were isolated from human gingival crevices and characterized. these strains were gram-negative, straight rods that were motile by means of multiple unipolar flagella. they were asaccharolytic and preferred an anaerobic atmosphere rather than a microaerophilic atmosphere for growth, and their growth was stimulated by formate and fumarate. these strains were biochemically similar to campylobacter curvus and campylobacter rectus, but were clearly distinguishable from ...19937694633
recent taxonomic changes for anaerobic gram-positive and selected gram-negative organisms.the strains formerly classified as streptococcus anginosus or "streptococcus milleri" have now been recognized as three distinct species, streptococcus anginosus, streptococcus constellatus, and streptococcus intermedius. streptococcus morbillorum has been transferred into the genus gemella. four new species within the genus peptostreptococcus were recently named. a recent addition to the genus clostridium is clostridium argentinense, which includes clostridium botulinum type g. two new species ...19938324113
helicobacter acinonyx sp. nov., isolated from cheetahs with gastritis.four strains of a novel helicobacter species were isolated from the stomachs of cheetahs (acinonyx jubilatus) with gastritis. these isolates were phenotypically similar to helicobacter pylori. the isolates were gram-negative, spiral bacteria which grew under microaerophilic conditions at 37 degrees c, but not at 25 or 42 degrees c, and produced urease, catalase, oxidase, alkaline phosphatase, and gamma-glutamyl transpeptidase. the isolates did not ferment glucose, mannitol, inositol, sorbitol, r ...19938379970
recently described clinically important anaerobic bacteria: taxonomic aspects and update.a new method of identifying bacteria, phylogenetic 16s rrna sequencing, has led to major reorganizations among most genera of anaerobic bacteria. the pigmented prevotella species now comprise seven species including p. nigrescens and p. tannerae; p. intermedia/p. nigrescens-like organisms await inclusion. the former mitsuokella dentalis and hallella seregens were transferred to prevotella as one species, p. dentalis. p. enoeca is a new nonpigmenting prevotella. the genus porphyromonas currently ...19979310640
relationship between c-telopeptide pyridinoline cross-links (ictp) and putative periodontal pathogens in periodontitis.crevicular fluid pyridinoline cross-linked carboxyterminal telopeptide of type i collagen (ictp) is predictive for future alveolar bone loss in experimental periodontitis in dogs. the present study sought to relate ictp to a panel of subgingival species in subjects exhibiting various clinical presentations such as health (n=7), gingivitis (n=8) and periodontitis (n=21). 28 subgingival plaque and gcf samples were taken from mesiobuccal sites in each of 36 subjects. the presence and levels of 40 s ...19989846794
design and evaluation of useful bacterium-specific pcr primers that amplify genes coding for bacterial 16s rrna.we report the design and evaluation of pcr primers 63f and 1387r for amplification of 16s rrna genes from bacteria. their specificity and efficacy were tested systematically with a bacterial species and environmental samples. they were found to be more useful for 16s rrna gene amplification in ecological and systematic studies than pcr amplimers that are currently more generally used.19989464425
c-telopeptide pyridinoline cross-links (ictp) and periodontal pathogens associated with endosseous oral implants.detection of periodontal or peri-implant sites exhibiting progressing disease or those at risk of deterioration has proven difficult. pyridinoline cross-linked carboxyterminal telopeptide of type i collagen (ictp), a marker specific for bone degradation found in gingival crevicular fluid (gcf), has been associated with both bone and attachment loss in periodontitis and may be useful for predicting disease activity. the aim of this cross-sectional study was to examine the relationship between ict ...199811429938
rapid detection of the chlamydiaceae and other families in the order chlamydiales: three pcr tests.few identification methods will rapidly or specifically detect all bacteria in the order chlamydiales, family chlamydiaceae. in this study, three pcr tests based on sequence data from over 48 chlamydial strains were developed for identification of these bacteria. two tests exclusively recognized the chlamydiaceae: a multiplex test targeting the ompa gene and the rrna intergenic spacer and a taqman test targeting the 23s ribosomal dna. the multiplex test was able to detect as few as 200 inclusion ...19999986815
are campylobacter curvus and campylobacter upsaliensis antecedent infectious agents in guillain-barré and fisher's syndromes?campylobacter curvus and campylobacter upsaliensis were isolated from stools of patients with guillain-barré (gbs) or fisher's (fs) syndromes. whether these microorganisms are pathogens of antecedent diarrhea in gbs and fs is not clear, therefore, we made a serological examination. there were no differences in antibody titer to these organisms among the patients with gbs, fs, and the controls. some patients had elevated antibodies to the bacteria, but most also had serological evidence of c. jej ...199910223411
rapid identification of campylobacter, arcobacter, and helicobacter isolates by pcr-restriction fragment length polymorphism analysis of the 16s rrna gene.a rapid two-step identification scheme based on pcr-restriction fragment length polymorphism (pcr-rflp) analysis of the 16s rrna gene was developed in order to differentiate isolates belonging to the campylobacter, arcobacter, and helicobacter genera. for 158 isolates (26 reference cultures and 132 clinical isolates), specific rflp patterns were obtained and species were successfully identified by this assay.199910565952
prevalence of campylobacter, arcobacter, helicobacter, and sutterella spp. in human fecal samples as estimated by a reevaluation of isolation methods for campylobacters.the aims of this study were to investigate the prevalence of campylobacteria including campylobacter jejuni subsp. jejuni (c. jejuni) and campylobacter coli in human clinical samples and in samples from healthy individuals and to reevaluate the efficacies of conventional selective methods for isolation of campylobacter spp. two charcoal-based selective media, modified charcoal cefoperazone deoxycholate agar (mccda) and cefoperazone-amphotericin-teicoplanin (cat) agar, were compared with skirrow' ...200010618103
interactions between periodontal bacteria and human oral epithelial cells: fusobacterium nucleatum adheres to and invades epithelial cells.bacteria are causative agents of periodontal diseases. interactions between oral bacteria and gingival epithelial cells are essential aspects of periodontal infections. using an in vitro tissue culture model, a selected group of gram-negative anaerobic bacteria frequently associated with periodontal diseases, including bacteroides forsythus, campylobacter curvus, eikenella corrodens, fusobacterium nucleatum, porphyromonas gingivalis, and prevotella intermedia, were examined for their ability to ...200010816455
rapid detection of campylobacter jejuni in stool specimens by an enzyme immunoassay and surveillance for campylobacter upsaliensis in the greater salt lake city area.the alexon-trend, inc. (ramsey, minn.), prospect campylobacter microplate assay was compared with culture on a campy-cva plate (remel, lenexa, kans.) and blood-free campylobacter agar with cefoperazone (20 microg/ml), amphotericin b (10 microg/ml), and teicoplanin (4 microg/ml) (cat medium; oxoid limited, hampshire, england) with 631 patient stool samples. the cat medium was used to isolate campylobacter upsaliensis. the enzyme immunoassay (eia) had a sensitivity and a specificity of 89 and 99%, ...200010921981
efficient isolation of campylobacteria from stools. 200010979752
efficient isolation of campylobacter upsaliensis from stools. 200111712518
in vitro activities of faropenem against 579 strains of anaerobic bacteria.the activity of faropenem, a new oral penem, was tested against 579 strains of anaerobic bacteria by using the nccls-approved reference method. drugs tested included amoxicillin-clavulanate, cefoxitin, clindamycin, faropenem, imipenem, and metronidazole. of the 176 strains of bacteroides fragilis group isolates tested, two isolates had faropenem mics of 64 micro g/ml and imipenem mics of >32 micro g/ml. faropenem had an mic of 16 micro g/ml for an additional isolate of b. fragilis; this strain w ...200212384389
activities of abt-773 against microaerophilic and fastidious organisms.abt-773 was tested against 317 fastidious isolates; it inhibited 99% of organisms at a concentration of 4.0 microg/ml. with ampicillin-sulbactam and levofloxacin, only 2 and 6% of these strains, respectively, were resistant at the breakpoint. with clindamycin, penicillin g, and metronidazole, 22, 26, and 58% of the strains, respectively, were resistant.200212121965
evaluation of 11 pcr assays for species-level identification of campylobacter jejuni and campylobacter coli.we examined the sensitivity and specificity of 11 pcr assays described for the species identification of campylobacter jejuni and campylobacter coli by using 111 type, reference, and field strains of c. jejuni, c. coli, and campylobacter lari. for six assays, an additional 21 type strains representing related campylobacter, arcobacter, and helicobacter species were also included. pcr tests were initially established in the laboratory by optimizing conditions with respect to five type and referen ...200312517869
multiplex pcr assay for differentiation of helicobacter felis, h. bizzozeronii, and h. salomonis.helicobacter felis, helicobacter bizzozeronii, and helicobacter salomonis are frequently found in the gastric mucous membrane of dogs and cats. these large spiral organisms are phylogenetically highly related to each other. their fastidious nature makes it difficult to cultivate them in vitro, hampering traditional identification methods. we describe here a multiplex pcr test based on the trna intergenic spacers and on the urease gene, combined with capillary electrophoresis, that allows discrim ...200415004062
direct quantification of campylobacter jejuni and campylobacter lanienae in feces of cattle by real-time quantitative pcr.campylobacter species are fastidious to culture, and the ability to directly quantify biomass in microbiologically complex substrates using real-time quantitative (rtq) pcr may enhance our understanding of their biology and facilitate the development of efficacious mitigation strategies. this study reports the use of nested rtq-pcr to directly quantify campylobacter jejuni and campylobacter lanienae in cattle feces. for c. jejuni, the single-copy mapa gene was selected. for c. lanienae, the thre ...200415066825
detection of campylobacter spp. in chicken fecal samples by real-time pcr.a real-time pcr assay for detecting thermophilic campylobacter spp. directly in chicken feces has been developed. dna was isolated from fecal material by using magnetic beads followed by pcr with a prealiquoted pcr mixture, which had been stored at -18 degrees c. campylobacter could be detected in less than 4 h, with a detection limit of 100 to 150 cfu/ml, in a fecal suspension. a bacterial internal control was added before dna extraction to control both dna isolation and the presence of pcr inh ...200415528705
differentiation of campylobacter coli, campylobacter jejuni, campylobacter lari, and campylobacter upsaliensis by a multiplex pcr developed from the nucleotide sequence of the lipid a gene lpxa.we describe a multiplex pcr assay to identify and discriminate between isolates of campylobacter coli, campylobacter jejuni, campylobacter lari, and campylobacter upsaliensis. the c. jejuni isolate f38011 lpxa gene, encoding a udp-n-acetylglucosamine acyltransferase, was identified by sequence analysis of an expression plasmid that restored wild-type lipopolysaccharide levels in escherichia coli strain sm105 [lpxa(ts)]. with oligonucleotide primers developed to the c. jejuni lpxa gene, nearly fu ...200415583280
description of campylobacter curvus and c. curvus-like strains associated with sporadic episodes of bloody gastroenteritis and brainerd's diarrhea.campylobacter curvus is a rarely encountered campylobacter species in human, animal, and environmental samples. during the course of two investigations, one involving a search for possible bacterial agents causing bloody gastroenteritis and a second concerning a small outbreak of brainerd's diarrhea in northern california, 20 strains of c. curvus or c. curvus-like organisms were isolated by a microfiltration technique and prolonged incubation. the results suggest that c. curvus may be an underap ...200515695649
oral campylobacter species involved in extraoral abscess: a report of three cases.oral campylobacter species are rarely reported to cause extraoral infections. here we present three cases of extraoral abscess caused by an oral campylobacter sp. and a streptococcus sp. the campylobacter species were all isolated anaerobically and identified by sequencing analysis of the 16s rrna gene. the cases included a breast abscess caused by campylobacter rectus and a non-group a beta-hemolytic streptococcus in a patient with lymphoma, a liver abscess caused by campylobacter curvus and an ...200515872299
identification of candidate periodontal pathogens and beneficial species by quantitative 16s clonal analysis.most studies of the bacterial etiology of periodontitis have used either culture-based or targeted dna approaches, and so it is likely that pathogens remain undiscovered. the purpose of this study was to use culture-independent, quantitative analysis of biofilms associated with chronic periodontitis and periodontal health to identify pathogens and beneficial species. samples from subjects with periodontitis and controls were analyzed using ribosomal 16s cloning and sequencing. several genera, ma ...200516081935
biochemical differentiation and comparison of desulfovibrio species and other phenotypically similar genera.seventeen human clinical isolates representing four species of desulfovibrio were characterized using 16s rrna gene sequences and tests for catalase, indole, nitrate, bile, urease, formate-fumarate stimulation, desulfoviridin, motility, and hydrogen sulfide production, plus susceptibility to antimicrobial agents. eighty additional strains representing 10 phenotypically similar genera (bilophila, selenomonas, capnocytophaga, campylobacter, bacteroides, sutterella, anaerobiospirillum, dialister, v ...200516081948
cultivable oral microbiota of domestic dogs.bacteria were isolated from the dental plaques of nine dogs and a sample of pooled saliva from five other dogs and were then identified by comparative 16s rrna gene sequencing. among 339 isolates, 84 different phylotypes belonging to 37 genera were identified. approximately half of the phylotypes were identified to the species level, and 28% of these were considered members of the indigenous oral microbiota of humans. the 16s rrna gene sequences of the remaining 44 phylotypes were not represente ...200516272472
campylobacter curvus-associated hepatic abscesses: a case report.campylobacter curvus was isolated from blood cultures of a patient with liver abscesses. bacterial identification involved gram staining, biochemical analysis, gas-liquid chromatography, and 16s rrna sequencing. the difficulty in isolation, identification, and growth of the species confirms previous work that these organisms may be overlooked by conventional detection methods.200616672438
dark matter in a deep-sea vent and in human mouth. 200717803764
the complete genome sequence and analysis of the epsilonproteobacterium arcobacter butzleri.arcobacter butzleri is a member of the epsilon subdivision of the proteobacteria and a close taxonomic relative of established pathogens, such as campylobacter jejuni and helicobacter pylori. here we present the complete genome sequence of the human clinical isolate, a. butzleri strain rm4018.200718159241
high content of proteins containing 21st and 22nd amino acids, selenocysteine and pyrrolysine, in a symbiotic deltaproteobacterium of gutless worm olavius algarvensis.selenocysteine (sec) and pyrrolysine (pyl) are rare amino acids that are cotranslationally inserted into proteins and known as the 21st and 22nd amino acids in the genetic code. sec and pyl are encoded by uga and uag codons, respectively, which normally serve as stop signals. herein, we report on unusually large selenoproteomes and pyrroproteomes in a symbiont metagenomic dataset of a marine gutless worm, olavius algarvensis. we identified 99 selenoprotein genes that clustered into 30 families, ...200717626042
evaluation of 16s rrna gene-based pcr assays for genus-level identification of helicobacter species.the inclusivity, exclusivity, and detection limit of six 16s rrna gene-based helicobacter genus-specific pcr assays were examined. five out of six assays were 100% inclusive, but the tests varied considerably in their exclusivity (9.1 to 95.5%). the clinical detection limit varied between 10(3) and 1 viable bacterial cell per reaction mixture.200818337392
bacterial profiles of root caries in elderly patients.culture-based studies have shown that streptococcus mutans and lactobacilli are associated with root caries (rc). the purpose of the present study was to assess the bacterial diversity of rc in elderly patients by use of culture-independent molecular techniques and to determine the associations of specific bacterial species or bacterial communities with healthy and carious roots. plaque was collected from root surfaces of 10 control subjects with no rc and from 11 subjects with rc. the bacterial ...200818385433
can campylobacter coli induce guillain-barré syndrome? 200919002726
can campylobacter coli induce guillain-barré syndrome? 200919002726
structural analysis of the dna-binding domain of the helicobacter pylori response regulator arsr.the helicobacter pylori arss-arsr two-component signal transduction system, comprised of a sensor histidine kinase (arss) and a response regulator (arsr), allows the bacteria to regulate gene expression in response to acidic ph. we expressed and purified the full-length arsr protein and the dna-binding domain of arsr (arsr-dbd), and we analyzed the tertiary structure of the arsr-dbd using solution nuclear magnetic resonance (nmr) methods. both the full-length arsr and the arsr-dbd behaved as mon ...200919117956
campylobacter fetus-associated epidural abscess and bacteremia.campylobacter fetus has been isolated as an infrequent cause of abscesses. we report a case of campylobacter fetus epidural abscess and bacteremia in a debilitated elderly man who had a fatal outcome.200919144805
comparative studies of campylobacter jejuni genomic diversity reveal the importance of core and dispensable genes in the biology of this enigmatic food-borne pathogen.mlst, dna microarrays, and genome sequencing has allowed for a greater understanding of the metabolic capacity and epidemiology of campylobacter jejuni. while strain-specific genes may provide an isolate a selective advantage in environments and contribute to the organism's pathogenicity, recent work indicates that c. jejuni pathogenicity is dictated by variations in the nucleotide sequence of core genes. challenges facing c. jejuni researchers include determining (a) the degree to which genomic ...200919346123
characterization of two homologous disulfide bond systems involved in virulence factor biogenesis in uropathogenic escherichia coli cft073.disulfide bond (dsb) formation is catalyzed by disulfide bond proteins and is critical for the proper folding and functioning of secreted and membrane-associated bacterial proteins. uropathogenic escherichia coli (upec) strains possess two paralogous disulfide bond systems: the well-characterized dsbab system and the recently described dsbli system. in the dsbab system, the highly oxidizing dsba protein introduces disulfide bonds into unfolded polypeptides by donating its redox-active disulfide ...200919376849
comparison of the entericbio multiplex pcr system with routine culture for detection of bacterial enteric pathogens.the entericbio system uses a multiplex pcr assay for the simultaneous detection of campylobacter spp., salmonella enterica, shigella spp., and escherichia coli o157 from feces. it combines overnight broth enrichment with pcr amplification and detection by hybridization. an evaluation of this system was conducted by comparing the results obtained with the system with those obtained by routine culture, supplemented with alternative pcr detection methods. in a study of 773 samples, routine culture ...200919726596
the dif/xer recombination systems in proteobacteria.in e. coli, 10 to 15% of growing bacteria produce dimeric chromosomes during dna replication. these dimers are resolved by xerc and xerd, two tyrosine recombinases that target the 28-nucleotide motif (dif) associated with the chromosome's replication terminus. in streptococci and lactococci, an alternative system is composed of a unique, xer-like recombinase (xers) genetically linked to a dif-like motif (dif(sl)) located at the replication terminus. preliminary observations have suggested that t ...200919727445
functional analysis of the helicobacter pylori flagellar switch proteins.helicobacter pylori uses flagellum-mediated chemotaxis to promote infection. bacterial flagella change rotational direction by changing the state of the flagellar motor via a subcomplex referred to as the switch. intriguingly, the h. pylori genome encodes four switch complex proteins, flim, flin, fliy, and flig, instead of the more typical three of escherichia coli or bacillus subtilis. our goal was to examine whether and how all four switch proteins participate in flagellation. previous work de ...200919767432
novel electrochemically active bacterium phylogenetically related to arcobacter butzleri, isolated from a microbial fuel cell.exoelectrogenic bacteria are organisms that can transfer electrons to extracellular insoluble electron acceptors and have the potential to be used in devices such as microbial fuel cells (mfcs). currently, exoelectrogens have been identified in the alpha-, beta-, gamma- and deltaproteobacteria, as well as in the firmicutes and acidobacteria. here, we describe use of culture-independent methods to identify two members of the genus arcobacter in the epsilonproteobacteria that are selectively enric ...200919801475
a study in entire chromosomes of violations of the intra-strand parity of complementary nucleotides (chargaff's second parity rule).chargaff's rule of intra-strand parity (isp) between complementary mono/oligonucleotides in chromosomes is well established in the scientific literature. although a large numbers of papers have been published citing works and discussions on isp in the genomic era, scientists are yet to find all the factors responsible for such a universal phenomenon in the chromosomes. in the present work, we have tried to address the issue from a new perspective, which is a parallel feature to isp. the composit ...200919861381
a genomic island defines subspecies-specific virulence features of the host-adapted pathogen campylobacter fetus subsp. venerealis.the pathogen campylobacter fetus comprises two subspecies, c. fetus subsp. fetus and c. fetus subsp. venerealis. although these taxa are highly related on the genome level, they are adapted to distinct hosts and tissues. c. fetus subsp. fetus infects a diversity of hosts, including humans, and colonizes the gastrointestinal tract. in contrast, c. fetus subsp. venerealis is largely restricted to the bovine genital tract, causing epidemic abortion in these animals. in light of their close genetic ...201019897645
a genomic island defines subspecies-specific virulence features of the host-adapted pathogen campylobacter fetus subsp. venerealis.the pathogen campylobacter fetus comprises two subspecies, c. fetus subsp. fetus and c. fetus subsp. venerealis. although these taxa are highly related on the genome level, they are adapted to distinct hosts and tissues. c. fetus subsp. fetus infects a diversity of hosts, including humans, and colonizes the gastrointestinal tract. in contrast, c. fetus subsp. venerealis is largely restricted to the bovine genital tract, causing epidemic abortion in these animals. in light of their close genetic ...201019897645
the internal transcribed spacer region, a new tool for use in species differentiation and delineation of systematic relationships within the campylobacter genus.the campylobacter genus consists of a number of important human and animal pathogens. although the 16s rrna gene has been used extensively for detection and identification of campylobacter species, there is currently limited information on the 23s rrna gene and the internal transcribed spacer (its) region that lies between the 16s and 23s rrna genes. we examined the potential of the 23s rrna gene and the its region to be used in species differentiation and delineation of systematic relationships ...201020348308
evidence for a lineage of virulent bacteriophages that target campylobacter.our understanding of the dynamics of genome stability versus gene flux within bacteriophage lineages is limited. recently, there has been a renewed interest in the use of bacteriophages as 'therapeutic' agents; a prerequisite for their use in such therapies is a thorough understanding of their genetic complement, genome stability and their ecology to avoid the dissemination or mobilisation of phage or bacterial virulence and toxin genes. campylobacter, a food-borne pathogen, is one of the organi ...201020353581
the hp0256 gene product is involved in motility and cell envelope architecture of helicobacter pylori.helicobacter pylori is the causative agent for gastritis, and peptic and duodenal ulcers. the bacterium displays 5-6 polar sheathed flagella that are essential for colonisation and persistence in the gastric mucosa. the biochemistry and genetics of flagellar biogenesis in h. pylori has not been fully elucidated. bioinformatics analysis suggested that the gene hp0256, annotated as hypothetical, was a flij homologue. in salmonella, flij is a chaperone escort protein for flgn and flit, two proteins ...201020377912
characterization of n-linked protein glycosylation in helicobacter pullorum.the first bacterial n-linked glycosylation system was discovered in campylobacter jejuni, and the key enzyme involved in the coupling of glycan to asparagine residues within the acceptor sequon of the glycoprotein is the oligosaccharyltransferase pglb. emerging genome sequence data have revealed that pglb orthologues are present in a subset of species from the deltaproteobacteria and epsilonproteobacteria, including three helicobacter species: h. pullorum, h. canadensis, and h. winghamensis. in ...201020581208
obstacles of multiplex real-time pcr for bacterial 16s rdna: primer specifity and dna decontamination of taq polymerase.background: the detection of a broad range of bacteria by pcr is applied for the screening of blood and blood products with special attention to platelet concentrates. for practical use it is desirable that detection systems include gram-positive, gram-negative and non-gram-stainable bacteria. it is quite challenging to achieve high sensitivity along with a clear negative control with pcr reagents, because especially taq polymerase is contaminated with traces of bacterial dna. methods: bacterial ...201020737013
bacterial 16s sequence analysis of severe caries in young permanent teeth.previous studies have confirmed the association of the acid producers streptococcus mutans and lactobacillus spp. with childhood caries, but they also suggested these microorganisms are not sufficient to explain all cases of caries. in addition, health-associated bacterial community profiles are not well understood, including the importance of base production and acid catabolism in ph homeostasis. the bacterial community composition in health and in severe caries of the young permanent dentition ...201020826648
enteric campylobacteria and rna viruses associated with healthy and diarrheic humans in the chinook health region of southwestern alberta, canada.the presence of campylobacter species and enteric rna viruses in stools from diarrheic (n = 442) and healthy (n = 58) humans living in southwestern alberta was examined (may to october 2005). a large number of diarrheic individuals who were culture negative for c. jejuni (n = 54) or c. coli (n = 19) were pcr positive for these taxa. overall detection rates for c. jejuni and c. coli in diarrheic stools were 29% and 5%, respectively. in contrast, 3% and 0% of stools from healthy humans were positi ...201021106791
enteric campylobacteria and rna viruses associated with healthy and diarrheic humans in the chinook health region of southwestern alberta, canada.the presence of campylobacter species and enteric rna viruses in stools from diarrheic (n = 442) and healthy (n = 58) humans living in southwestern alberta was examined (may to october 2005). a large number of diarrheic individuals who were culture negative for c. jejuni (n = 54) or c. coli (n = 19) were pcr positive for these taxa. overall detection rates for c. jejuni and c. coli in diarrheic stools were 29% and 5%, respectively. in contrast, 3% and 0% of stools from healthy humans were positi ...201021106791
comparative analysis of sequence periodicity among prokaryotic genomes points to differences in nucleoid structure and a relationship to gene expression.regular spacing of short runs of a or t nucleotides in dna sequences with a period close to the helical period of the dna double helix has been associated with intrinsic dna bending and nucleosome positioning in eukaryotes. analogous periodic signals were also observed in prokaryotic genomes. while the exact role of this periodicity in prokaryotes is not known, it has been proposed to facilitate the dna packaging in the prokaryotic nucleoid and/or to promote negative or positive supercoiling. we ...201020494989
a score of the ability of a three-dimensional protein model to retrieve its own sequence as a quantitative measure of its quality and appropriateness.despite the remarkable progress of bioinformatics, how the primary structure of a protein leads to a three-dimensional fold, and in turn determines its function remains an elusive question. alignments of sequences with known function can be used to identify proteins with the same or similar function with high success. however, identification of function-related and structure-related amino acid positions is only possible after a detailed study of every protein. folding pattern diversity seems to ...201020830209
the large-scale organization of the bacterial network of ecological co-occurrence interactions.in their natural environments, microorganisms form complex systems of interactions. understating the structure and organization of bacterial communities is likely to have broad medical and ecological consequences, yet a comprehensive description of the network of environmental interactions is currently lacking. here, we mine co-occurrences in the scientific literature to construct such a network and demonstrate an expected pattern of association between the species' lifestyle and the recorded nu ...201020194113
four pcr primers necessary for the detection of periplasmic nitrate reductase genes in all groups of proteobacteria and in environmental dna.generic primers are available for detecting bacterial genes required for almost every reaction of the biological nitrogen cycle, the one notable exception being napa (gene for the molybdoprotein of the periplasmic nitrate reductase) encoding periplasmic nitrate reductases. using an iterative approach, we report the first successful design of three forward oligonucleotide primers and one reverse primer that, in three separate pcrs, can amplify napa dna from all five groups of proteobacteria. all ...201121265796
rna-oligonucleotide quantification technique (roqt) for the enumeration of uncultivated bacterial species in subgingival biofilms.approximately 35% of the species present in subgingival biofilms are as yet uncultivated, so their role in periodontal pathogenesis is unknown. the aim of the present study was to develop a high throughput method to quantify a wide range of cultivated and uncultivated taxa in subgingival biofilm samples associated with periodontal disease or health. oligonucleotides targeting the 16s ribosomal dna gene were designed, synthesized and labeled with digoxigenin. these probes were hybridized with the ...201121375703
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
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
occurrence of putative virulence genes in arcobacter species isolated from humans and animals.interest for arcobacters in veterinary and human public health has increased since the first report of the isolation of arcobacters from food of animal origin. since then, studies worldwide have reported the occurrence of arcobacters on food and in food-production animals and have highlighted the possible transmission of especially a. butzleri to the human population. in humans, arcobacters are associated with enteritis and septicemia. to assess their clinical relevance for humans and animals, e ...201122170914
comparative analyses of campylobacter concisusstrains reveal the genome of the reference strain baa-1457 is not representative of the species.abstract:201121992484
annotation of protein domains reveals remarkable conservation in the functional make up of proteomes across superkingdoms.the functional repertoire of a cell is largely embodied in its proteome, the collection of proteins encoded in the genome of an organism. the molecular functions of proteins are the direct consequence of their structure and structure can be inferred from sequence using hidden markov models of structural recognition. here we analyze the functional annotation of protein domain structures in almost a thousand sequenced genomes, exploring the functional and structural diversity of proteomes. we find ...201124710297
methods of combinatorial optimization to reveal factors affecting gene length.in this paper we present a novel method for genome ranking according to gene lengths. the main outcomes described in this paper are the following: the formulation of the genome ranking problem, presentation of relevant approaches to solve it, and the demonstration of preliminary results from prokaryotic genomes ordering. using a subset of prokaryotic genomes, we attempted to uncover factors affecting gene length. we have demonstrated that hyperthermophilic species have shorter genes as compared ...201223300345
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
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
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
differences in dna curvature-related sequence periodicity between prokaryotic chromosomes and phages, and relationship to chromosomal prophage content.periodic spacing of a-tracts (short runs of a or t) with the dna helical period of ~10-11 bp is characteristic of intrinsically bent dna. in eukaryotes, the dna bending is related to chromatin structure and nucleosome positioning. however, the physiological role of strong sequence periodicity detected in many prokaryotic genomes is not clear.201222587570
multilocus sequence typing methods for the emerging campylobacter species c. hyointestinalis, c. lanienae, c. sputorum, c. concisus, and c. curvus.multilocus sequence typing (mlst) systems have been reported previously for multiple food- and food animal-associated campylobacter species (e.g., c. jejuni, c. coli, c. lari, and c. fetus) to both differentiate strains and identify clonal lineages. these mlst methods focused primarily on campylobacters of human clinical (e.g., c. jejuni) or veterinary (e.g., c. fetus) relevance. however, other, emerging, campylobacter species have been isolated increasingly from environmental, food animal, or h ...201222919636
investigation of the enteric pathogenic potential of oral campylobacter concisus strains isolated from patients with inflammatory bowel disease.campylobacter concisus, a bacterium colonizing the human oral cavity, has been shown to be associated with inflammatory bowel disease (ibd). this study investigated if patients with ibd are colonized with specific oral c. concisus strains that have potential to cause enteric diseases.201222666490
deamination of 6-aminodeoxyfutalosine in menaquinone biosynthesis by distantly related enzymes.proteins of unknown function belonging to cog1816 and cog0402 were characterized. sav2595 from steptomyces avermitilis ma-4680, acel0264 from acidothermus cellulolyticus 11b, nis0429 from nitratiruptor sp. sb155-2 and dr0824 from deinococcus radiodurans r1 were cloned, purified, and their substrate profiles determined. these enzymes were previously incorrectly annotated as adenosine deaminases or chlorohydrolases. it was shown here that these enzymes actually deaminate 6-aminodeoxyfutalosine. th ...201323972005
comprehensive genomic characterization of campylobacter genus reveals some underlying mechanisms for its genomic diversification.campylobacter species.are phenotypically diverse in many aspects including host habitats and pathogenicities, which demands comprehensive characterization of the entire campylobacter genus to study their underlying genetic diversification. up to now, 34 campylobacter strains have been sequenced and published in public databases, providing good opportunity to systemically analyze their genomic diversities. in this study, we first conducted genomic characterization, which includes genome-wide alig ...201323940551
bacterial protein n-glycosylation: new perspectives and applications.protein glycosylation is widespread throughout all three domains of life. bacterial protein n-glycosylation and its application to engineering recombinant glycoproteins continue to be actively studied. here, we focus on advances made in the last 2 years, including the characterization of novel bacterial n-glycosylation pathways, examination of pathway enzymes and evolution, biological roles of protein modification in the native host, and exploitation of the n-glycosylation pathways to create nov ...201323329827
the microaerophilic microbiota of de-novo paediatric inflammatory bowel disease: the biscuit study.children presenting for the first time with inflammatory bowel disease (ibd) offer a unique opportunity to study aetiological agents before the confounders of treatment. microaerophilic bacteria can exploit the ecological niche of the intestinal epithelium; helicobacter and campylobacter are previously implicated in ibd pathogenesis. we set out to study these and other microaerophilic bacteria in de-novo paediatric ibd.201323554935
effect of antimicrobial growth promoter administration on the intestinal microbiota of beef cattle.antimicrobial growth promoters (agps) are antimicrobial agents administered to livestock in feed for prolonged periods to enhance feed efficiency. beef cattle are primarily finished in confined feeding operations in canada and the usa, and the administration of agps such as chlortetracycline and sulfamethazine (aureo s-700 g) is the standard. the impacts of agps on the intestinal microbiota of beef cattle are currently uncertain; it is documented that agps administered to beef cattle pass throug ...201323578222
identification of anaerobic bacteria by bruker biotyper matrix-assisted laser desorption ionization-time of flight mass spectrometry with on-plate formic acid preparation.identification of anaerobic bacteria using phenotypic methods is often time-consuming; methods such as 16s rrna gene sequencing are costly and may not be readily available. we evaluated 253 clinical isolates of anaerobic bacteria using the bruker maldi biotyper (bruker daltonics, billerica, ma) matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) system with a user-supplemented database and an on-plate formic acid-based preparation method and compared resul ...201323254126
occurrence and characteristics of fastidious campylobacteraceae species in porcine samples.this study investigated the prevalence and characteristics of campylobacteraceae including a range of fastidious species in porcine samples. over a thirteen month period caecal contents (n=402) and pork carcass swabs (n=401) were collected from three pork abattoirs and pork products (n=399) were purchased at point of sale in the republic of ireland. campylobacteraceae isolates were recovered by enrichment, membrane filtration and incubation in antibiotic free media under a modified atmosphere (3 ...201323474652
a consortium of aggregatibacter actinomycetemcomitans, streptococcus parasanguinis, and filifactor alocis is present in sites prior to bone loss in a longitudinal study of localized aggressive periodontitis.aggregatibacter actinomycetemcomitans-induced localized aggressive periodontitis (lap) in african-american adolescents has been documented but is poorly understood. two thousand fifty-eight adolescents aged 11 to 17 years were screened for their periodontal status and the presence of a. actinomycetemcomitans in their oral cavity. seventy-one a. actinomycetemcomitans-negative and 63 a. actinomycetemcomitans-positive periodontally healthy subjects were enrolled, sampled, examined, and radiographed ...201323784124
pathogens and host immunity in the ancient human oral cavity.calcified dental plaque (dental calculus) preserves for millennia and entraps biomolecules from all domains of life and viruses. we report the first, to our knowledge, high-resolution taxonomic and protein functional characterization of the ancient oral microbiome and demonstrate that the oral cavity has long served as a reservoir for bacteria implicated in both local and systemic disease. we characterize (i) the ancient oral microbiome in a diseased state, (ii) 40 opportunistic pathogens, (iii) ...201424562188
genomic evidence for the emergence and evolution of pathogenicity and niche preferences in the genus campylobacter.the genus campylobacter includes some of the most relevant pathogens for human and animal health; the continuous effort in their characterization has also revealed new species putatively involved in different kind of infections. nowadays, the available genomic data for the genus comprise a wide variety of species with different pathogenic potential and niche preferences. in this work, we contribute to enlarge this available information presenting the first genome for the species campylobacter sp ...201425193310
detection, identification and quantification of campylobacter jejuni, coli and lari in food matrices all at once using multiplex qpcr.thermotolerant campylobacter jejuni, coli and lari are recognized as leading food-borne pathogens causing an acute bacterial enteritis worldwide. due to narrow spectrum of their biochemical activity, it is very complicated to distinguish between individual species. for reliable risk assessment, proper incidence evaluation or swift sample analysis regarding individual species, a demand for simple and rapid method for their distinguishing is reasonable. in this study, we evaluated a reliable and s ...201425057300
biological roles of the o-methyl phosphoramidate capsule modification in campylobacter jejuni.campylobacter jejuni is a major cause of bacterial gastroenteritis worldwide, and the capsular polysaccharide (cps) of this organism is required for persistence and disease. c. jejuni produces over 47 different capsular structures, including a unique o-methyl phosphoramidate (meopn) modification present on most c. jejuni isolates. although the meopn structure is rare in nature it has structural similarity to some synthetic pesticides. in this study, we have demonstrated, by whole genome comparis ...201424498018
identification and characterization of an invasion antigen b gene from the oral pathogen campylobacter rectus.the oral bacterium, campylobacter rectus, is an etiological agent of periodontitis. the virulence genes of c. rectus are largely unknown. the aim of this study was to query c. rectus for the presence of an invasion antigen b (ciab) gene, which is needed for cell invasion by the related species campylobacter jejuni. pcr and pcr-walking identified a ciab from c. rectus. in silico analyses of c. rectus 314 ciab (cr-ciab) revealed an orf of 1,830 base pairs. the cr-ciab protein shared significant se ...201424426164
identification and characterization of an invasion antigen b gene from the oral pathogen campylobacter rectus.the oral bacterium, campylobacter rectus, is an etiological agent of periodontitis. the virulence genes of c. rectus are largely unknown. the aim of this study was to query c. rectus for the presence of an invasion antigen b (ciab) gene, which is needed for cell invasion by the related species campylobacter jejuni. pcr and pcr-walking identified a ciab from c. rectus. in silico analyses of c. rectus 314 ciab (cr-ciab) revealed an orf of 1,830 base pairs. the cr-ciab protein shared significant se ...201424426164
biofilm community diversity after exposure to 0·4% stannous fluoride gels.to test the effect of 0·4% stannous fluoride (snf2 ) glycerine-based gels on specific portions of the bacterial community in both a clinical observational study and in vitro multispecies plaque-derived (mspd) biofilm model.201425263195
potential involvement of campylobacter curvus and haemophilus parainfluenzae in preterm birth.a woman presented with prelabour premature preterm rupture of membranes and delivered extremely preterm at 26 weeks by caesarean section. histopathology of the placenta indicated moderately severe histological chorioamnionitis with dense infiltration of the chorionic plate by neutrophils. two sets of low and high vaginal swabs were taken from the mother. a set sent for microbiological analysis at the hospital yielded negative results. the second set was analysed employing culture-independent hig ...201425274558
identification and characterization of a putative chemotaxis protein, chey, from the oral pathogen campylobacter rectus.campylobacter rectus is an understudied oral bacterium that contributes to periodontitis. processes that contribute to the disease-causing capabilities of pathogens, such as chemotaxis, are largely unknown in c. rectus. the aim of this study was to better understand c. rectus chemotaxis, by examining the c. rectus genome for the presence of a chey gene. chey proteins play a part in chemotaxis by acting as two-component response regulators. significantly, chey proteins from several pathogens, inc ...201425598863
novel type ii and monomeric nad+ specific isocitrate dehydrogenases: phylogenetic affinity, enzymatic characterization, and evolutionary implication.nad(+) use is an ancestral trait of isocitrate dehydrogenase (idh), and the nadp(+) phenotype arose through evolution as an ancient adaptation event. however, no nad(+)-specific idhs have been found among type ii idhs and monomeric idhs. in this study, novel type ii homodimeric nad-idhs from ostreococcus lucimarinus cce9901 idh (olidh) and micromonas sp. rcc299 (miidh), and novel monomeric nad-idhs from campylobacter sp. fobrc14 idh (caidh) and campylobacter curvus (ccidh) were reported for the ...201525775177
oral campylobacter species: initiators of a subgroup of inflammatory bowel disease?in recent years, a number of studies detected a significantly higher prevalence of campylobacter species such as campylobacter concisus (c. concisus) in intestinal biopsies and fecal samples collected from patients with inflammatory bowel disease (ibd) compared to controls. most of these campylobacter species are not of zoonotic origin but are human oral campylobacter species. bacterial species usually cause diseases in the location where they colonize. however, c. concisus and other oral campyl ...201526309350
bacteremia caused by arcobacter butzleri in an immunocompromised host.arcobacter butzleri is an emerging pathogen that has been implicated as the causative agent of persistent watery diarrhea. we describe a case involving a patient with chronic lymphocytic leukemia who developed invasive a. butzleri bacteremia. this case illustrates the unique challenges involved in diagnosing infections caused by emerging gastrointestinal pathogens.201525673792
evolution of the selenoproteome in helicobacter pylori and epsilonproteobacteria.by competing for the acquisition of essential nutrients, helicobacter pylori has the unique ability to persist in the human stomach, also causing nutritional insufficiencies in the host. although the h. pylori genome apparently encodes selenocysteine synthase (sela, hp1513), a key pyridoxal phosphate (plp)-dependent enzyme for the incorporation of selenium into bacterial proteins, nothing is known about the use of this essential element in protein synthesis by this pathogen. we analyzed the evol ...201526342139
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