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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
long-term survival of campylobacter jejuni at low temperatures is dependent on polynucleotide phosphorylase activity.campylobacter jejuni is a leading cause of bacterial gastroenteritis worldwide. infection generally occurs after ingestion of contaminated poultry products, usually conserved at low temperatures. the mechanisms promoting survival of c. jejuni in the cold remain poorly understood despite several investigations. the present study provides insight into the survival mechanism by establishing the involvement of polynucleotide phosphorylase (pnpase), a 3'-5' exoribonuclease with multiple biological fu ...200919801468
campylobacter fetus cellulitis in an immunocompromised patient: case report and review of the literature.campylobacter fetus is an opportunist gram-negative bacillus. the most frequent clinical manifestation is bacteriemia but it can also be responsable for soft tissue infections, endovascular infections, meningitis, peritonitis and thrombophlebitis. campylobacter fetus cellulitis has been described, but rarely identified in subcutaneous puncture samples. we report a case of an immunocompromised patient with campylobacter fetus bacteriemia associated with a soft tissue infection whose subcutaneous ...200919810424
campylobacter fetus subspecies venerealis transport medium for enrichment and pcr. 200919855114
rapid evolution and the importance of recombination to the gastroenteric pathogen campylobacter jejuni.responsible for the majority of bacterial gastroenteritis in the developed world, campylobacter jejuni is a pervasive pathogen of humans and animals, but its evolution is obscure. in this paper, we exploit contemporary genetic diversity and empirical evidence to piece together the evolutionary history of c. jejuni and quantify its evolutionary potential. our combined population genetics-phylogenetics approach reveals a surprising picture. campylobacter jejuni is a rapidly evolving species, subje ...200919008526
rapid evolution and the importance of recombination to the gastroenteric pathogen campylobacter jejuni.responsible for the majority of bacterial gastroenteritis in the developed world, campylobacter jejuni is a pervasive pathogen of humans and animals, but its evolution is obscure. in this paper, we exploit contemporary genetic diversity and empirical evidence to piece together the evolutionary history of c. jejuni and quantify its evolutionary potential. our combined population genetics-phylogenetics approach reveals a surprising picture. campylobacter jejuni is a rapidly evolving species, subje ...200919008526
the biofilm forming potential of bacterial species in the genus campylobacter.the biofilm forming abilities of 16 strains representative of 14 of the 16 species comprising the genus campylobacter were determined on glass, stainless steel, and polystyrene plastic. the formation of biofilms has been suggested as a means by which campylobacter is able to persist within an inhospitable environment. of the eight microaerophilic campylobacter species, including two strains each of campylobacter jejuni and campylobacter fetus, only c. jejuni strain 81-176 reliably produced a vis ...200919028304
increased tlr4 expression in murine placentas after oral infection with periodontal pathogens.maternal periodontitis has emerged as a putative risk factor for preterm births in humans. the periodontitis-associated dental biofilm is thought to serve as an important source of oral bacteria and related virulence factors that hematogenously disseminate and affect the fetoplacental unit; however the underlying biological mechanisms are yet to be fully elucidated. this study hypothesized that an oral infection with the human periodontal pathogens campylobacter rectus and porphyromonas gingival ...200919101032
increased tlr4 expression in murine placentas after oral infection with periodontal pathogens.maternal periodontitis has emerged as a putative risk factor for preterm births in humans. the periodontitis-associated dental biofilm is thought to serve as an important source of oral bacteria and related virulence factors that hematogenously disseminate and affect the fetoplacental unit; however the underlying biological mechanisms are yet to be fully elucidated. this study hypothesized that an oral infection with the human periodontal pathogens campylobacter rectus and porphyromonas gingival ...200919101032
development of a loop-mediated isothermal amplification assay for sensitive and rapid detection of campylobacter fetus.we developed a sensitive and rapid loop-mediated isothermal amplification (lamp) assay for detection of campylobacter fetus. this assay provides simpler and more rapid detection of c. fetus than conventional biochemical and pcr assays. the assay correctly detected 60 c. fetus strains but not 55 non-fetuscampylobacter and 30 non-campylobacter strains. the sensitivity of the lamp assay in pure cultures and in a spiked bovine liver specimen was 10-fold more sensitive than that of the conventional p ...200919128899
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
campylobacter cholecystitis.there are 13 cases of campylobacter cholecystitis reported so far in the medical literature. among them, only 4 patients had diarrhea. we report another case of acalculous cholecystitis in a setting of campylobacter enteritis. the case report is followed by a literature review regarding this rare condition.200919960123
campylobacter fetus meningitis in a patient with crohn's disease. 200918798576
forty years' experience treating septic arteritis and vasculitis.by their natures, septic arteritis and infected grafts present a high morbidity and mortality situation for both the patient and the treating physician. in the experience of the authors, therapy frequently includes removing the previous infected graft, use of long-term antibiotics, repeat grafting and omental wraps. when possible, aortic endografting followed by future elective primary repair may be considered an option. leaving wounds open to granulate from the 'bottom up' has been successful i ...200922477474
antibody-based sensors: principles, problems and potential for detection of pathogens and associated toxins.antibody-based sensors permit the rapid and sensitive analysis of a range of pathogens and associated toxins. a critical assessment of the implementation of such formats is provided, with reference to their principles, problems and potential for 'on-site' analysis. particular emphasis is placed on the detection of foodborne bacterial pathogens, such as escherichia coli and listeria monocytogenes, and additional examples relating to the monitoring of fungal pathogens, viruses, mycotoxins, marine ...200922408533
rapid identification of bacterial pathogens using a pcr- and microarray-based assay.during the course of a bacterial infection, the rapid identification of the causative agent(s) is necessary for the determination of effective treatment options. we have developed a method based on a modified broad-range pcr and an oligonucleotide microarray for the simultaneous detection and identification of 12 bacterial pathogens at the species level. the broad-range pcr primer mixture was designed using conserved regions of the bacterial topoisomerase genes gyrb and pare. the primer design a ...200919664269
fastidious gram-negatives: identification by the vitek 2 neisseria-haemophilus card and by partial 16s rrna gene sequencing analysis.taxonomy and identification of fastidious gram negatives are evolving and challenging. we compared identifications achieved with the vitek 2 neisseria-haemophilus (nh) card and partial 16s rrna gene sequence (526 bp stretch) analysis with identifications obtained with extensive phenotypic characterization using 100 fastidious gram negative bacteria. seventy-five strains represented 21 of the 26 taxa included in the vitek 2 nh database and 25 strains represented related species not included in th ...201021347215
rtx proteins: a highly diverse family secreted by a common mechanism.repeats-in-toxin (rtx) exoproteins of gram-negative bacteria form a steadily growing family of proteins with diverse biological functions. their common feature is the unique mode of export across the bacterial envelope via the type i secretion system and the characteristic, typically nonapeptide, glycine- and aspartate-rich repeats binding ca(2+) ions. in this review, we summarize the current state of knowledge on the organization of rtx loci and on the biological and biochemical activities of t ...201020528947
aminoglycoside modifying enzymes.aminoglycosides have been an essential component of the armamentarium in the treatment of life-threatening infections. unfortunately, their efficacy has been reduced by the surge and dissemination of resistance. in some cases the levels of resistance reached the point that rendered them virtually useless. among many known mechanisms of resistance to aminoglycosides, enzymatic modification is the most prevalent in the clinical setting. aminoglycoside modifying enzymes catalyze the modification at ...201020833577
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
origin and evolution of peptide-modifying dioxygenases and identification of the wybutosine hydroxylase/hydroperoxidase.unlike classical 2-oxoglutarate and iron-dependent dioxygenases, which include several nucleic acid modifiers, the structurally similar jumonji-related dioxygenase superfamily was only known to catalyze peptide modifications. using comparative genomics methods, we predict that a family of jumonji-related enzymes catalyzes wybutosine hydroxylation/peroxidation at position 37 of eukaryotic trnaphe. identification of this enzyme raised questions regarding the emergence of protein- and nucleic acid- ...201020423905
macrophages recognize size and shape of their targets.recognition by macrophages is a key process in generating immune response against invading pathogens. previous studies have focused on recognition of pathogens through surface receptors present on the macrophage's surface. here, using polymeric particles of different geometries that represent the size and shape range of a variety of bacteria, the importance of target geometry in recognition was investigated. the studies reported here reveal that attachment of particles of different geometries to ...201020386614
prolonged survival of campylobacter species in bovine manure compost.the persistence of naturally occurring campylobacteria in aerobic compost constructed of manure from beef cattle that were administered chlortetracycline and sulfamethazine (as700) or from cattle not administered antibiotics (control) was examined. although there were no differences in population sizes of heterotrophic bacteria, the temperature of as700 compost was more variable and did not become as high as that of control compost. there were significant differences in water content, total carb ...201020023098
development and evaluation of an indirect enzyme-linked immunosorbent assay for the detection of antibodies against campylobacter fetus in cattle.campylobacteriosis is a zoonosis that occurs worldwide. infection with campylobacter fetus (c. fetus) causes infertility and abortion in sheep and cattle. the current study focuses on the sapa gene of c. fetus that encodes surface array proteins and plays an important role in the virulence of c. fetus. the sapa-n (1398bp) and sapa-c (1422bp) fragments were amplified from the c. fetussapa gene using polymerase chain reaction (pcr), and the corresponding recombinant proteins rsapa-n and rsapa-c we ...201020035963
genetic relationships among reptilian and mammalian campylobacter fetus strains determined by multilocus sequence typing.reptile campylobacter fetus isolates and closely related strains causing human disease were characterized by multilocus sequence typing. they shared approximately 90% nucleotide sequence identity with classical mammalian c. fetus, and there was evidence of recombination among members of these two groups. the reptile group represents a possible separate genomospecies capable of infecting humans.201020053851
spondylodiscitis and an aortic aneurysm due to campylobacter coli.campylobacter coli is a rare cause of bacteremia. we report here the first case of c.coli spondylodiscitis complicated by an aortic aneurysm. outcome was favourable with surgery and antibiotic therapy.201020132561
campylobacter fetus peritonitis in a patient with an unused embedded subcutaneous peritoneal catheter. 201020200376
modification of the campylobacter jejuni flagellin glycan by the product of the cj1295 homopolymeric-tract-containing gene.the campylobacter jejuni flagellin protein is o-glycosylated with structural analogues of the nine-carbon sugar pseudaminic acid. the most common modifications in the c. jejuni 81-176 strain are the 5,7-di-n-acetylated derivative (pse5ac7ac) and an acetamidino-substituted version (pse5am7ac). other structures detected include o-acetylated and n-acetylglutamine-substituted derivatives (pse5am7ac8oac and pse5am7ac8glnnac, respectively). recently, a derivative of pseudaminic acid modified with a di ...201020338909
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
recurrent gram-negative bloodstream infection: a 10-year population-based cohort study.recurrent gram-negative bloodstream infection (bsi) has not been evaluated in a population-based setting; therefore, we performed a population-based retrospective cohort study to examine the incidence, recurrence, and mortality rates of gram-negative bsi.201020378069
imipenem-resistant campylobacter fetus bloodstream infection. 201020435578
two novel antibiotic resistance genes, tet(44) and ant(6)-ib, are located within a transferable pathogenicity island in campylobacter fetus subsp. fetus.new tetracycline and streptomycin resistance genes, tet(44) and ant(6)-ib, were identified in campylobacter fetus subsp. fetus within a transferable pathogenicity island that is typically unique to campylobacter fetus subsp. venerealis. the 640-amino-acid tetracycline resistance determinant, tet 44, belongs to a class of proteins that confers resistance to tetracycline and minocycline by ribosomal protection. the 286-amino-acid streptomycin resistance determinant, ant(6)-ib, belongs to a family ...201020479200
three-hour molecular detection of campylobacter, salmonella, yersinia, and shigella species in feces with accuracy as high as that of culture.campylobacter jejuni and salmonella, shigella, and yersinia species (along with shiga toxin-producing escherichia coli) are the most common causes of acute bacterial diarrheal disease in the united states. current detection techniques are time-consuming, limiting usefulness for patient care. we developed and validated a panel of rapid pcr assays for the detection and identification of c. jejuni, c. coli, salmonella, and yersinia species and shigella and enteroinvasive e. coli in stool samples. a ...201020519461
the rdgc protein employs a novel mechanism involving a finger domain to bind to circular dna.the dna-binding protein rdgc has been identified as an inhibitor of reca-mediated homologous recombination in escherichia coli. in neisseria species, rdgc also has a role in virulence-associated antigenic variation. we have previously solved the crystal structure of the e. coli rdgc protein and shown it to form a toroidal dimer. in this study, we have conducted a mutational analysis of residues proposed to mediate interactions at the dimer interfaces. we demonstrate that destabilizing either int ...201020525790
performance of the oxoid m.i.c.evaluator strips compared with the etest assay and bsac agar dilution.the oxoid m.i.c.evaluator (m.i.c.e; thermo fisher scientific) comprises an antibiotic gradient on a plastic support. we compared its performance with etest--a similar product--using bsac agar dilution as a reference.201020562429
occurrence and sequence of sphaeroides heme protein and diheme cytochrome c in purple photosynthetic bacteria in the family rhodobacteraceae.sphaeroides heme protein (shp) was discovered in the purple photosynthetic bacterium, rhodobacter sphaeroides, and is the only known c-type heme protein that binds oxygen. although initially not believed to be widespread among the photosynthetic bacteria, the gene has now been found in more than 40 species of proteobacteria and generally appears to be regulated. rb. sphaeroides is exceptional in not having regulatory genes associated with the operon. we have thus analyzed additional purple bacte ...201020587053
campylobacter fetus translocation across caco-2 cell monolayers.campylobacter fetus is a recognized pathogen of cattle and sheep, though human infection has also been reported. ingestion of contaminated food or water is a proposed route of transmission for both humans and animals. the subsequent detection of the organism from extra-intestinal and systemic locations implies an ability to translocate across epithelial barriers. to determine how c. fetus disseminates from the intestine, caco-2 cells cultured on porous membrane supports, were used as model intes ...201020600794
development of loop-mediated isothermal amplification and pcr assays for rapid and simple detection of campylobacter fetus subsp. venerealis.campylobacter fetus is divided into cfv and cff. because cfv causes bovine genital campylobacteriosis, differentiation of the two subspecies is essential to the implementation of efficient cfv control and eradication programs. we have developed lamp and duplex pcr assays for rapid and simple detection of cfv. the lamp assay correctly detected 7 cfv strains and did not detect 53 cff, 35 non-fetus campylobacter and 25 non-campylobacter strains. the pcr assay successfully differentiated the two sub ...201020618686
campylobacter fetus subspecies fetus spondylodiscitis.campylobacter spp. are common causes of gastrointestinal infections. campylobacter fetus is a much rarer pathogen in humans, and usually causes bacteraemia and systemic complications in patients with predisposing conditions. we report a case of spondylodiscitis caused by c. fetus subsp. fetus as revealed by vertebral biopsy culture. this identification was confirmed by sequencing the 16s rrna gene and by phylogenetic analysis. treatment consisted of 6 weeks antimicrobial therapy combined with a ...201020705728
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
new bacteriological patterns in primary infected aorto-iliac aneurysms: a single-centre experience.to assess causative pathogens and surgical outcomes in patients with primary infected aorto-iliac aneurysms at our institution.201020843713
isolation of a novel campylobacter jejuni clone associated with the bank vole, myodes glareolus.campylobacter jejuni can be isolated from different animal hosts. various studies have used multilocus sequence typing to look for associations between particular clones of c. jejuni and specific hosts. here, we describe the isolation of a novel clone (sequence type 3704 [st-3704]) of c. jejuni associated with the bank vole (myodes glareolus).201020851991
detection of antibodies specific to campylobacter fetus subsp. venerealis in the vaginal mucus of nigerian breeding cows.the presence of bovine venereal campylobacteriosis in the lake chad basin of nigeria was investigated using an enzyme-linked immunosorbent assay (elisa) for the detection of iga antibodies specific to campylobacter fetus subsp. venerealis in vaginal mucus (n = 66). iga antibodies specific to c. fetus subsp. venerealis were detected in 7 (11%) vaginal mucus samples. all but one of the iga-positive samples originated from cows belonging to herds with a history of abortion and infertility which sug ...201020857383
campylobacter fetus subspecies fetus abortion in alpacas (vicugna pacos). 201020862815
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
interbacterial macromolecular transfer by the campylobacter fetus subsp. venerealis type iv secretion system.we report here the first demonstration of intra- and interspecies conjugative plasmid dna transfer for campylobacter fetus. gene regions carried by a campylobacter coli plasmid were identified that are sufficient for conjugative mobilization to escherichia coli and c. fetus recipients. a broader functional range is predicted. efficient dna transfer involves the virb9 and vird4 genes of the type iv bacterial secretion system encoded by a pathogenicity island of c. fetus subsp. venerealis. complem ...201021115658
vitamin b(6) is required for full motility and virulence in helicobacter pylori.despite recent advances in our understanding of how helicobacter pylori causes disease, the factors that allow this pathogen to persist in the stomach have not yet been fully characterized. to identify new virulence factors in h. pylori, we generated low-infectivity variants of a mouse-colonizing h. pylori strain using the classical technique of in vitro attenuation. the resulting variants and their highly infectious progenitor bacteria were then analyzed by global gene expression profiling. the ...201021151756
phenotypic and genotypic evidence for l-fucose utilization by campylobacter jejuni.campylobacter jejuni remains among the leading causes of bacterial food-borne illness. the current understanding of campylobacter physiology suggests that it is asaccharolytic and is unable to catabolize exogenous carbohydrates. contrary to this paradigm, we provide evidence for l-fucose utilization by c. jejuni. the fucose phenotype, shown in chemically defined medium, is strain specific and linked to an 11-open reading frame (orf) plasticity region of the bacterial chromosome. by constructing ...201021193610
phenotypic and genotypic evidence for l-fucose utilization by campylobacter jejuni.campylobacter jejuni remains among the leading causes of bacterial food-borne illness. the current understanding of campylobacter physiology suggests that it is asaccharolytic and is unable to catabolize exogenous carbohydrates. contrary to this paradigm, we provide evidence for l-fucose utilization by c. jejuni. the fucose phenotype, shown in chemically defined medium, is strain specific and linked to an 11-open reading frame (orf) plasticity region of the bacterial chromosome. by constructing ...201021193610
evaluation of pcr assays for the detection of campylobacter fetus in bovine preputial scrapings and the identification of subspecies in south african field isolates.as a result of the high lability and slow growth of campylobacter fetus subspecies, the laboratory diagnosis of bovine genital campylobacteriosis has always been difficult. this is especially true under south african conditions, where farms are far apart, laboratories are only present in major centres and there are high ambient temperatures. in order to overcome the shortcomings associated with traditional diagnostic methods, the implementation of a molecular assay was sought. this work describe ...201021247013
campylobacter fetus peritonitis and bacteremia in a patient undergoing continuous ambulatory peritoneal dialysis.we report a case of campylobacter fetus peritonitis and bacteremia in a patient undergoing continuous ambulatory peritoneal dialysis.201019889904
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
new molecular microbiology approaches in the study of campylobacter fetus.campylobacter fetus infection is a substantial problem in herds of domestic cattle worldwide and a rising threat in human disease. application of comparative and functional genomics approaches will be essential to understand the molecular basis of this pathogen's interactions with various hosts. here we report recent progress in genome analyses of c. fetus ssp. fetus and c. fetus ssp. venerealis, and the development of molecular tools to determine the genetic basis of niche-specific adaptations. ...201121255368
cross-reaction of a campylobacter fetus subspecies venerealis real-time pcr. 201121257600
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
campylobacter capsule and lipooligosaccharide confer resistance to serum and cationic antimicrobials.the innate immune system plays a critical role in host defense against mucosal bacteria. campylobacter jejuni is a major cause of human gastroenteritis that usually resolves spontaneously within several days, suggesting that innate mechanisms are important to control the infection. however, the specific means by which this occurs is not well understood. while diarrheal isolates of c. jejuni usually are susceptible to human serum, we found that a systemic strain of c. jejuni, isolated from the ce ...201121266840
histopathological, immunohistochemical, lectinhistochemical and molecular findings in spontaneous bovine abortions by campylobacter fetus.bovine campylobacteriosis (bc) is a venereal disease caused by campylobacter fetus characterized by temporary infertility with mild endometritis, early embryonic death and occasional abortions. the objectives of this study were to describe and identify c. fetus in spontaneous bovine abortion on the basis of histopathological, immunohistochemical, lectinhistochemical and polymerase chain reaction (pcr) techniques. the most frequent foetal lesion was neutrophilic bronchopneumonia and interstitial ...201120626679
hospital epidemiology and infection control in acute-care settings.health care-associated infections (hais) have become more common as medical care has grown more complex and patients have become more complicated. hais are associated with significant morbidity, mortality, and cost. growing rates of hais alongside evidence suggesting that active surveillance and infection control practices can prevent hais led to the development of hospital epidemiology and infection control programs. the role for infection control programs has grown and continues to grow as rat ...201121233510
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
primary infected abdominal aortic aneurysm: surgical procedures, early mortality rates, and a survey of the prevalence of infectious organisms over a 30-year period.the purpose of this study was to analyze the surgical procedures, culture results, and outcomes, and to survey the prevalence of the infectious organisms over a 30-year period in patients with a primary infected abdominal aortic aneurysm (piaaa).201121365414
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
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
genome sequence of helicobacter suis supports its role in gastric pathology.abstract: helicobacter (h.) suis has been associated with chronic gastritis and ulcers of the pars oesophagea in pigs, and with gastritis, peptic ulcer disease and gastric mucosa-associated lymphoid tissue lymphoma in humans. in order to obtain better insight into the genes involved in pathogenicity and in the specific adaptation to the gastric environment of h. suis, a genome analysis was performed of two h. suis strains isolated from the gastric mucosa of swine. homologs of the vast majority o ...201121414191
phylogenetic distribution and evolutionary history of bacterial dead-box proteins.dead-box proteins are found in all domains of life and participate in almost all cellular processes that involve rna. the presence of dead and helicase_c conserved domains distinguish these proteins. dead-box proteins exhibit rna-dependent atpase activity in vitro, and several also show rna helicase activity. in this study, we analyzed the distribution and architecture of dead-box proteins among bacterial genomes to gain insight into the evolutionary pathways that have shaped their history. we i ...201121437710
emerging thermotolerant campylobacter species in healthy ruminants and swine.campylobacters other than campylobacter jejuni or c. coli were isolated in 35% of 343 farms recently analyzed in northern spain. this study was aimed at identifying at the species level the 120 isolates collected (21 ovine, 52 beef cattle, 44 dairy cattle, and 3 porcine) by species-specific polymerase chain reaction and 16s rrna gene sequencing analysis. thus, five species were identified: campylobacter hyointestinalis (90 isolates), campylobacter lanienae (12), campylobacter fetus subsp. fetus ...201121438765
immunity to infections in the lower genital tract of bulls.the mucosa of the bovine prepuce has unique immunological characteristics critical to defense against sexually transmitted diseases. tritrichomonas foetus and campylobacter fetus subspecies venerealis persistently colonize the lower genital tract of bulls but usually do not cause either major clinical signs or inflammation. these microbes may be sexually transmitted to female cattle to cause reproductive failure. although the male genital immune responses to t. foetus and c. fetus subspecies ven ...201121474188
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
simultaneous peritoneal dialysis-associated peritonitis and bacteremia due to ceftriaxone-resistant campylobacter fetus. 201121555425
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
serological survey of toxoplasma gondii and campylobacter fetus fetus in sheep from new zealand.to determine the prevalence of antibody titres to toxoplasma gondii and campylobacter fetus fetus in sheep from new zealand.201121660843
a bacterial process for selenium nanosphere assembly.during selenate respiration by thauera selenatis, the reduction of selenate results in the formation of intracellular selenium (se) deposits that are ultimately secreted as se nanospheres of approximately 150 nm in diameter. we report that the se nanospheres are associated with a protein of approximately 95 kda. subsequent experiments to investigate the expression and secretion profile of this protein have demonstrated that it is up-regulated and secreted in response to increasing selenite conce ...201121808043
factors associated with infection by campylobacter fetus in beef herds in the province of buenos aires, argentina.campylobacter fetus is a major venereal pathogen of cattle that is considered to be widespread among the livestock population of argentina. the disease accounts for a 10% reduction in the weaning rate of argentine infected herds and annual losses of $165 million. a case-control, questionnaire-based study was developed with the objective of quantifying the association between c. fetus infection and demographic, husbandry, and sanitary factors in 196 herds located in the province of buenos aires, ...201121737166
a role for tlr4 in clostridium difficile infection and the recognition of surface layer proteins.clostridium difficile is the etiological agent of antibiotic-associated diarrhoea (aad) and pseudomembranous colitis in humans. the role of the surface layer proteins (slps) in this disease has not yet been fully explored. the aim of this study was to investigate a role for slps in the recognition of c. difficile and the subsequent activation of the immune system. bone marrow derived dendritic cells (dcs) exposed to slps were assessed for production of inflammatory cytokines, expression of cell ...201121738466
changes in bacterial diversity associated with epithelial tissue in the beef cow rumen during the transition to a high-grain diet.our understanding of the ruminal epithelial tissue-associated bacterial (defined as epimural bacteria in this study) community is limited. in this study, we aimed to determine whether diet influences the diversity of the epimural bacterial community in the bovine rumen. twenty-four beef heifers were randomly assigned to either a rapid grain adaptation (rga) treatment (n = 18) in which the heifers were allowed to adapt from a diet containing 97% hay to a diet containing 8% hay over 29 days or to ...201121705529
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
aids cholangiopathy in an asymptomatic, previously undiagnosed late-stage hiv-positive patient from kenya.aids-associated cholangiopathy is a form of biliary tract inflammation with stricture formation seen in aids patients who are severely immunosuppressed. it is no longer common in countries in which haart therapy is widely employed but is still seen in underdeveloped countries. the majority of patients are symptomatic at the time of presentation. herein, we describe a seventy-four-year-old woman who presented with unilateral leg swelling after a prolonged airplane flight. she was otherwise entire ...201121994858
antimicrobial susceptibility testing of german campylobacter fetus subsp. venerealis isolates by agar disk diffusion method.campylobacter fetus subsp. venerealis is the causative agent of bovine genital campylobacteriosis and is transmitted by asymptomatic carrier bulls via contaminated semen during artificial insemination. the aim of the present study was to determine the in vitro susceptibility of campylobacter fetus subsp. venerealis isolated from bovine specimens in the years from 2000 to 2009 in germany to antibiotics generally used in semen treatment. the susceptibilities of 50 strains to spectinomycin (10 micr ...201122059289
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
Development of a set of multiplex standard polymerase chain reaction assays for the identification of infectious agents from aborted bovine clinical samples.The current study describes the development of a set of 5 multiplex polymerase chain reaction (mPCR) assays for the simultaneous detection of abortive infection agents in bovine fetal tissues, including Brucella spp., Leptospira spp., and Campylobacter fetus (mPCR1); Hammondia heydorni, Neospora caninum, and Toxoplasma gondii (mPCR2); Coxiella burnetii and Chlamydophila psittaci (mPCR3); Mycoplasma bovis, Mycoplasma bovigenitalium, and Ureaplasma diversum (mPCR4); and Bovine viral diarrhea virus ...201121908306
[fatal bacteremia caused by campylobacter fetus and campylobacter jejuni in patients with alcoholic liver disease]. 201121947101
campylobacter fetus bacteremia in a young healthy adult transmitted by khat chewing.campylobacter fetus is a pathogen affecting almost exclusively patients with immunosuppression and chronic debilitating diseases. we report the case of a healthy young man with c. fetus bacteremia presenting with fever, hypotension and meningitis. the patient had no exposure to contaminated sources except from khat chewing, which we describe as a possible source of transmission for the first time.201122138599
sepsis and pericarditis caused by campylobacter fetus: case report and literature review.heretofore, campylobacter infections have been predominantly associated with gastrointestinal manifestations. over the past two decades, an increasing number of case reports have suggested that the spectrum of disease is much broader. to date, only 10 cases of myocarditis/pericarditis in patients with c. fetus have been reported in the english literature out of which at least 4 patients have died. we describe here a further case to include as we review the literature.201122016899
campylobacter fetus as cause of prosthetic valve endocarditis.a 65-year-old woman who had previously undergone aortic root replacement with a bioprosthetic valve (bentall operation) in treatment of annuloaortic ectasia became feverish after developing dental caries and was admitted to our hospital. transesophageal echocardiography showed an 18 × 4-mm vegetation on her prosthetic valve. campylobacter fetus was isolated on blood cultures, and she was diagnosed with infectious endocarditis. aggressive combined antibiotic treatment was effective for her recove ...201122163142
aortic homograft endocarditis caused by campylobacter jejuni.we report the first case of homograft endocarditis caused by campylobacter jejuni, which was treated successfully with antibiotic therapy and valve replacement. to our knowledge, only two other cases of c. jejuni endocarditis, involving native valves, have been reported in the medical literature.201121940472
a novel bacterial isolate from permian ground water capable of aggregating potential biofuel-producing microalga nannochloropsis oceanica imet1.increasing petroleum costs and climate change have resulted in microalgae receiving attention as potential biofuel producers. little information is available on the diversity and functions of bacterial communities associated with biofuel-producing algae. a potential biofuel-producing microalgal strain nannochloropsis oceanica imet1 was grown in permian ground water. changes in the bacterial community structure at three temperatures were monitored by two culture-independent methods and culturable ...201122194289
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
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
comparative in silico analysis of chemotaxis system of campylobacter fetus.chemoreceptor and chemotaxis signal transduction cascade genes of c. fetus subsp. fetus 82-40 show high level of similarity to that in c. jejuni and appears to include sixteen diverse transducer-like protein (tlp) genes that appear similar to nine of the twelve tlp genes in the c. jejuni nctc 11168 with a percent identity ranging from 15 to 50%. sixteen putative c. fetus 82-40 tlp genes belong to three classes: a, b, and c, as well as an aerotaxis gene, based on their predicted structure. c. fet ...201121983836
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
[bacteremia and endarteritis cases secondary to campylobacter spp. in a metropolitan hospital: our experience along a quarter of a century].six cases of bacteremia and one of endarteritis were identified between 1986 and 2010 in a general hospital in chile. five of these cases occurred during the second half of this timeframe, campylobacter fetus predominated (5 out of 7) and the majority of the infections presented during warmer months. the mean age was 32.4 years (range 19 to 63) all had comorbidities, and main clinical manifestations included fever with diarrhea. four patients developed hypotension and two septic shock. the latte ...201121879145
high prevalence of tritrichomonas foetus infection in asturiana de la montaña beef cattle kept in extensive conditions in northern spain.bovine trichomonosis (bt) and bovine genital campylobacteriosis (bgc) are sexually transmitted diseases that can be important infectious causes of reproductive failure in extensively managed beef cattle where natural mating is a common practice. however, their prevalence in europe was thought to be insignificant or very low. the purpose of this study was to investigate the prevalence and risk factors associated with bt and bcg in a representative beef cattle breed, asturiana de la montaña (am), ...201122178360
comparative analyses of campylobacter concisusstrains reveal the genome of the reference strain baa-1457 is not representative of the species.abstract:201121992484
complete genome sequence of type strain campylobacter fetus subsp. venerealis nctc 10354t.campylobacter fetus subsp. venerealis is the etiologic agent of bovine genital campylobacteriosis, a sexually transmitted disease of cattle that is of worldwide importance. the complete sequencing and annotation of the genome of the type strain c. fetus subsp. venerealis nctc 10354(t) are reported.201121952544
Staphylococcus hyicus Bacteremia in a Farmer.Bacteria known in animal infectious diseases can cause challenges in human diagnostic laboratories. We present pitfalls in the identification and susceptibility testing of Staphylococcus hyicus, a pathogen that typically causes exudative epidermitis in pigs. In this case, the coagulase-positive staphylococcus isolated from a septic patient was misidentified as Staphylococcus aureus.201121998429
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
Leptospirosis in beef herds from western Canada: Serum antibody titers and vaccination practices.One study described the frequency of pre-breeding vaccination for leptospirosis in 205 cow-calf herds from across western Canada and the prevalence of positive Leptospira antibody titers in unvaccinated, weaned calves from 61 of these herds. The percentages of herds vaccinated for leptospirosis were 13.7% in 2001 and 8.4% in 2002. Of 1539 calves examined, 13 (0.8%) had a positive antibody titer for a Leptospira serovar; the most common serovar detected was hardjo. A second study examined the pre ...201122131577
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