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prevalence, antibiogram and risk factors of thermophilic campylobacter spp. in dressed porcine carcass of chitwan, nepal.campylobacter is the primary cause of food borne gastroenteritis. moreover, the emergence of multiple drug resistant campylobacters from poultry and pork has produced a potential threat to public health. research addressing these issues is sparse in nepal. so, this cross-sectional study aims at determining the prevalence, antibiogram and risk factors of campylobacters from dressed porcine carcass of chitwan, nepal.201424708489
identification of a novel membrane transporter mediating resistance to organic arsenic in campylobacter jejuni.although bacterial mechanisms involved in the resistance to inorganic arsenic are well understood, the molecular basis for organic arsenic resistance has not been described. campylobacter jejuni, a major food-borne pathogen causing gastroenteritis in humans, is highly prevalent in poultry and is reportedly resistant to the arsenic compound roxarsone (4-hydroxy-3-nitrobenzenearsonic acid), which has been used as a feed additive in the poultry industry for growth promotion. in this study, we repor ...201424419344
detection of campylobacter in stool and determination of significance by culture, enzyme immunoassay, and pcr in developing countries.campylobacter is a common bacterial enteropathogen that can be detected in stool by culture, enzyme immunoassay (eia), or pcr. we compared culture for c. jejuni/c. coli, eia (prospect), and duplex pcr to distinguish campylobacter jejuni/c. coli and non-jejuni/coli campylobacter on 432 diarrheal and matched control stool samples from infants in a multisite longitudinal study of enteric infections in tanzania, bangladesh, and peru. the sensitivity and specificity of culture were 8.5% and 97.6%, re ...201424452175
comparison of the bd max enteric bacterial panel to routine culture methods for detection of campylobacter, enterohemorrhagic escherichia coli (o157), salmonella, and shigella isolates in preserved stool specimens.we compared the bd max enteric bacterial panel (ebp) to culture for the detection of salmonella, shigella, campylobacter, and shiga toxin-producing enterohemorrhagic escherichia coli (ehec) o157 in seeded stool samples. the ebp panel demonstrated superior sensitivity and reliably detected salmonella, ehec o157, shigella, and campylobacter at concentrations 1- to 2-log10 lower than those needed for culture detection.201424430460
evaluation of a loop-mediated isothermal amplification suite for the rapid, reliable, and robust detection of shiga toxin-producing escherichia coli in produce.shiga toxin-producing escherichia coli (stec) strains are a leading cause of produce-associated outbreaks in the united states. rapid, reliable, and robust detection methods are needed to better ensure produce safety. we recently developed a loop-mediated isothermal amplification (lamp) suite for stec detection. in this study, the stec lamp suite was comprehensively evaluated against real-time quantitative pcr (qpcr) using a large panel of bacterial strains (n = 156) and various produce items (s ...201424509927
distribution of indigenous bacterial pathogens and potential pathogens associated with roof-harvested rainwater.the harvesting of rainwater is gaining acceptance among many governmental authorities in countries such as australia, germany, and south africa, among others. however, conflicting reports on the microbial quality of harvested rainwater have been published. to monitor the presence of potential pathogenic bacteria during high-rainfall periods, rainwater from 29 rainwater tanks was sampled on four occasions (during june and august 2012) in a sustainable housing project in kleinmond, south africa. t ...201424487540
comparative analysis and limitations of ethidium monoazide and propidium monoazide treatments for the differentiation of viable and nonviable campylobacter cells.the lack of differentiation between viable and nonviable bacterial cells limits the implementation of pcr-based methods for routine diagnostic approaches. recently, the combination of a quantitative real-time pcr (qpcr) and ethidium monoazide (ema) or propidium monoazide (pma) pretreatment has been described to circumvent this disadvantage. in regard to the suitability of this approach for campylobacter spp., conflicting results have been reported. thus, we compared the suitabilities of ema and ...201424487529
molecular testing for clinical diagnosis and epidemiological investigations of intestinal parasitic infections.over the past few decades, nucleic acid-based methods have been developed for the diagnosis of intestinal parasitic infections. advantages of nucleic acid-based methods are numerous; typically, these include increased sensitivity and specificity and simpler standardization of diagnostic procedures. dna samples can also be stored and used for genetic characterization and molecular typing, providing a valuable tool for surveys and surveillance studies. a variety of technologies have been applied, ...201424696439
[bacterial biofilms: their importance in animal health and public health].bacterial biofilms are structured communities of bacterial cells enclosed in a self-produced polymer matrix that is attached to a surface. biofilms protect and allow bacteria to survive and thrive in hostile environments. bacteria within biofilms can withstand host immune responses, and are much less susceptible to antibiotics and disinfectants when compared to their planktonic counterparts. the ability to form biofilms is now considered an attribute of many microorganisms. diseases associated w ...201424688172
metabolomic profiling and antioxidant activity of some acacia species.metabolomic profiling of different parts (leaves, flowers and pods) of acacia species (acacia nilotica, acacia seyal and acacia laeta) was evaluated. the multivariate data analyses such as principal component analysis (pca) and partial least square-discriminant analysis (pls-da) were used to differentiate the distribution of plant metabolites among different species or different organs of the same species. a. nilotica was characterized with a high content of saponins and a. seyal was characteriz ...201425313274
perspectives in the use of tannins as alternative to antimicrobial growth promoter factors in poultry.antibiotics have been included in the formulation of feed for livestock production for more than 40 years as a strategy to improve feed conversion rates and to reduce costs. the use of antimicrobials as growth-promoting factors (agp) in sub-therapeutic doses for long periods is particularly favorable for the selection of antimicrobial resistant microorganisms. in the last years, global concern about development of antimicrobial resistance and transference of resistance genes from animal to human ...201424723916
a reference pan-genome approach to comparative bacterial genomics: identification of novel epidemiological markers in pathogenic campylobacter.the increasing availability of hundreds of whole bacterial genomes provides opportunities for enhanced understanding of the genes and alleles responsible for clinically important phenotypes and how they evolved. however, it is a significant challenge to develop easy-to-use and scalable methods for characterizing these large and complex data and relating it to disease epidemiology. existing approaches typically focus on either homologous sequence variation in genes that are shared by all isolates ...201424676150
alternative bacteriophage life cycles: the carrier state of campylobacter jejuni.members of the genus campylobacter are frequently responsible for human enteric disease, often through consumption of contaminated poultry products. bacteriophages are viruses that have the potential to control pathogenic bacteria, but understanding their complex life cycles is key to their successful exploitation. treatment of campylobacter jejuni biofilms with bacteriophages led to the discovery that phages had established a relationship with their hosts typical of the carrier state life cycle ...201424671947
isolation of a campylobacter lanienae-like bacterium from laboratory chinchillas (chinchilla laniger).routine necropsies of 27 asymptomatic juvenile chinchillas revealed a high prevalence of gastric ulcers with microscopic lymphoplasmacytic gastroenteritis and typhlocolitis. polymerase chain reaction (pcr) analysis using campylobacter genus-specific partial 16s rrna primers revealed the presence of campylobacter spp. dna in the faeces of 12 of 27 animals (44.4%). species-specific partial 16s rrna pcr and sequencing confirmed that these animals were colonized with campylobacter lanienae, a gram-n ...201424628887
draft genome sequence of campylobacter coli strain ipsid-1 isolated from a patient with immunoproliferative small intestinal disease.the genome sequence and annotation of campylobacter coli strain ipsid-1 are reported here. this bacterial isolate is the first to be cultured from a patient with immunoproliferative small intestinal disease (ipsid). the draft genome sequence is 1.683 mb long, comprises 64 contigs, and has 31.26% g+c content.201424625865
a multiplex pcr/ldr assay for simultaneous detection and identification of the niaid category b bacterial food and water-borne pathogens.enteric pathogens that cause gastroenteritis remain a major global health concern. the goal of this study was to develop a multiplex pcr/ligation detection reaction (ldr) assay for the detection of all niaid category b bacterial food and water-borne pathogens directly from stool specimens. to validate the pcr/ldr assay, clinical isolates of campylobacter spp., vibrio spp., shigella spp., salmonella spp., listeria monocytogenes, yersinia enterocolitica, and diarrheagenic escherichia coli were tes ...201424709368
prevalence of virulence genes in strains of campylobacter jejuni isolated from human, bovine and broiler.campylobacter jejuni isolates of different origins (bovine, broiler meat, human) were screened by polymerase chain reaction for the presence of 4 genes cdtb, cst-ii, ggt, and virb11, previously linked to virulence such as adherence, invasion, colonization, molecular mimicry, and cytotoxin production. in addition, the isolates were screened for the presence of the global gene regulator csra linked to oxidative stress responses, biofilms formation, and cell adhesion. all the c. jejuni isolates wer ...201424688515
prevalence and pathogenic potential of campylobacter isolates from free-living, human-commensal american crows.recent studies have suggested a potential role for wild birds in zoonotic transmission of campylobacter jejuni, the leading cause of gastroenteritis in humans worldwide. in this study, we detected campylobacter spp. in 66.9% (85/127) of free-ranging american crows (corvus brachyrhyncos) sampled in the sacramento valley of california in 2012 and 2013. biochemical testing and sequence analysis of 16s rrna revealed that 93% of isolates (n = 70) were c. jejuni, with cytolethal distending toxin (cdt) ...201424375131
divergent distribution of the sensor kinase coss in non-thermotolerant campylobacter species and its functional incompatibility with the response regulator cosr of campylobacter jejuni.two-component signal transduction systems are commonly composed of a sensor histidine kinase and a cognate response regulator, modulating gene expression in response to environmental changes through a phosphorylation-dependent process. cosr is an ompr-type response regulator essential for the viability of campylobacter jejuni, a major foodborne pathogenic species causing human gastroenteritis. although cosr is a response regulator, its cognate sensor kinase has not been identified in c. jejuni. ...201424587027
antimicrobial resistance of bacterial enteropathogens isolated from stools in madagascar.diarrheal diseases are a major public health problem in developing countries, and are one of the main causes of hospital admissions in madagascar. the pasteur institute of madagascar undertook a study to determine the prevalence and the pathogenicity of bacterial, viral and protozoal enteropathogens in diarrheal and non-diarrheal stools of children aged less than 5 years in madagascar. we present here the results of the analysis of antimicrobial susceptibility of the bacteria isolated during thi ...201424568189
comparative genomics of unintrogressed campylobacter coli clades 2 and 3.campylobacter jejuni and c. coli share a multitude of risk factors associated with human gastrointestinal disease, yet their phylogeny differs significantly. c. jejuni is scattered into several lineages, with no apparent linkage, whereas c. coli clusters into three distinct phylogenetic groups (clades) of which clade 1 has shown extensive genome-wide introgression with c. jejuni, yet the other two clades (2 and 3) have less than 2% of c. jejuni ancestry. we characterized a c. coli strain (76339) ...201424524824
a severe case of persistent diarrhoea associated with arcobacter cryaerophilus but attributed to campylobacter sp. and a review of the clinical incidence of arcobacter spp.although rarely, arcobacter spp. have been associated with diarrhoea and bacteraemia. we report a persistent case in a healthy 26-year-old spanish male of bloody diarrhoea, which was attributed to campylobacter but in fact was caused by arcobacter cryaerophilus, as determined by sequencing of the rpob gene. the isolate was re-identified by matrix-assisted laser desorption ionization time of flight (maldi-tof) and genotyped for five putative virulence genes and for seven genes included in the arc ...201425356338
mortality in captive baboons (papio spp.): a-23-year study.we report the causes of mortality for 4350 captive baboons that died or were euthanized due to natural causes during a 23 year period at the southwest national primate research center.201424483852
comparison of conventional pcr, multiplex pcr, and loop-mediated isothermal amplification assays for rapid detection of arcobacter species.this study aimed to develop a loop-mediated isothermal amplification (lamp) method for the rapid detection of arcobacter species. specific primers targeting the 23s ribosomal rna gene were used to detect arcobacter butzleri, arcobacter cryaerophilus, and arcobacter skirrowii. the specificity of the lamp primer set was assessed using dna samples from a panel of arcobacter and campylobacter species, and the sensitivity was determined using serial dilutions of arcobacter species cultures. lamp show ...201424478488
intersubspecific recombination in xylella fastidiosa strains native to the united states: infection of novel hosts associated with an unsuccessful invasion.the bacterial pathogen xylella fastidiosa infects xylem and causes disease in many plant species in the americas. different subspecies of this bacterium and different genotypes within subspecies infect different plant hosts, but the genetics of host adaptation are unknown. here we examined the hypothesis that the introduction of novel genetic variation via intersubspecific homologous recombination (ihr) facilitates host shifts. we investigated ihr in 33 x. fastidiosa subsp. multiplex isolates pr ...201424296499
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
presence and analysis of plasmids in human and animal associated arcobacter species.in this study, we report the screening of four arcobacter species for the presence of small and large plasmids. plasmids were present in 9.9% of the 273 examined strains. one arcobacter cryaerophilus and four arcobacter butzleri plasmids were selected for further sequencing. the size of three small plasmids isolated from a. butzleri and the one from a. cryaerophilus strains ranged between 4.8 and 5.1 kb, and the size of the large plasmid, isolated from a. butzleri, was 27.4 kbp. the g+c content ...201424465575
detection of cdt toxin genes in campylobacter spp. strains isolated from broiler carcasses and vegetables in são paulo, brazil.campylobacteriosis is a worldwide distributed zoonosis. one of the main virulence factors related to campylobacter spp. in animals and humans is the cytolethal distending toxin (cdt), encoded by three adjacent genes (cdta, cdtb, cdtc). the occurrence of campylobacter spp. in samples of vegetables has not been reported in brazil yet, and has seldom been described in the international literature. the detection of cdt in these strains has not been reported, either. the objectives of the present stu ...201424516435
isolation and antimicrobial susceptibility patterns of campylobacter species among diarrheic children at jimma, ethiopia.introduction. campylobacter is one of the leading bacterial causes of food-borne disease. the prevalence of campylobacter species resistant to antimicrobial agents is increasing. this study is intended to determine prevalence and antimicrobial susceptibility patterns of campylobacter species among under-five children with diarrhea. methodology. a cross-sectional study was conducted among 227 under-five children with diarrhea from july to october 2012 at jimma town. isolation and identification o ...201426904735
the renaissance of bacillosamine and its derivatives: pathway characterization and implications in pathogenicity.prokaryote-specific sugars, including n,n'-diacetylbacillosamine (dinacbac) and pseudaminic acid, have experienced a renaissance in the past decade because of their discovery in glycans related to microbial pathogenicity. dinacbac is found at the reducing end of oligosaccharides of n- and o-linked bacterial protein glycosylation pathways of gram-negative pathogens, including campylobacter jejuni and neisseria gonorrhoeae. further derivatization of dinacbac results in the nonulosonic acid known a ...201424383882
comparison of characteristics of patients infected by campylobacter jejuni, campylobacter coli, and campylobacter fetus.a large database of campylobacter isolates precisely identified at the species level was used to compare patients' characteristics. in a multivariate analysis, campylobacter coli was found more often in older patients and in patients having traveled abroad and less often in summertime than campylobacter jejuni. campylobacter fetus infection occurred in much older patients and in hospitalized patients with a systemic disease.201424197884
lipooligosaccharide locus class of campylobacter jejuni: sialylation is not needed for invasive infection.campylobacter jejuni is a highly diverse enteropathogen that is commonly detected worldwide. it can sometimes cause bacteraemia, but the bacterial characteristics facilitating bloodstream infection are not known. a total of 73 c. jejuni isolates, consecutively collected from blood-borne infections during a 10-year period all over finland and for which detailed clinical information of the patients were available, were included. we screened the isolates by pcr for the lipooligosaccharide (los) loc ...201424102802
target optimization for peptide nucleic acid (pna)-mediated antisense inhibition of the cmeabc multidrug efflux pump in campylobacter jejuni.cmeabc is a resistance-nodulation-cell division (rnd)-type multidrug efflux pump conferring resistance to clinically important antibiotics in campylobacter. this study aimed to identify the optimal target sites for the inhibition of cmeabc with antisense peptide nucleic acid (pna).201424084637
an epidemiological investigation of campylobacter in pig and poultry farms in the mekong delta of vietnam.campylobacter are zoonotic pathogens commonly associated with gastroenteritis. to assess the relevance of campylobacter in vietnam, an economically transitioning country in se asia, we conducted a survey of 343 pig and poultry farms in the mekong delta, a region characterized by mixed species farming with limited biosecurity. the animal-level prevalence of campylobacter was 31·9%, 23·9% and 53·7% for chickens, ducks and pigs, respectively. c. jejuni was predominant in all three host species, wit ...201424067502
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
survival in water of campylobacter jejuni strains isolated from the slaughterhouse.campylobacter jejuni cause gastroenteritis in humans. the main transmission vector is the consumption or handling of contaminated chicken meat, since chicken can be colonized asymptomatically by c. jejuni. however, water has been implicated as the transmission vector in a few outbreaks. one possibility is the contamination of water effluent by c. jejuni originating from chicken farm. the ability of c. jejuni to be transmitted by water would be closely associated to its ability to survive in wate ...201526702388
smrt sequencing of the campylobacter coli bfr-ca-9557 genome sequence reveals unique methylation motifs.campylobacter species are the most prevalent bacterial pathogen causing acute enteritis worldwide. in contrast to campylobacter jejuni, about 5 % of campylobacter coli strains exhibit susceptibility to restriction endonuclease digestion by dpni cutting specifically 5'-g(m)atc-3' motifs. this indicates significant differences in dna methylation between both microbial species. the goal of the study was to analyze the methylome of a c. coli strain susceptible to dpni digestion, to identify its meth ...201526689587
molecular identification of campylobacter jejuni and coli from chicken, calves and dogs to determine its potential threat on human being.campylobacter is an emerging zoonotic pathogen and one of the leading cause of foodborne infection worldwide and it has been isolated from a variety of animal species. the aim of this study was to identify campylobacter jejuni and campylobacter coli from dogs, calves, and poultry using polymerase chain reaction (pcr).201527047055
a flagellar glycan-specific protein encoded by campylobacter phages inhibits host cell growth.we previously characterized a carbohydrate binding protein, gp047, derived from lytic campylobacter phage nctc 12673, as a promising diagnostic tool for the identification of campylobacter jejuni and campylobacter coli. we also demonstrated that this protein binds specifically to acetamidino-modified pseudaminic acid residues on host flagella, but the role of this protein in the phage lifecycle remains unknown. here, we report that gp047 is capable of inhibiting c. jejuni growth both on solid an ...201526694450
weakly deleterious mutations and low rates of recombination limit the impact of natural selection on bacterial genomes.free-living bacteria are usually thought to have large effective population sizes, and so tiny selective differences can drive their evolution. however, because recombination is infrequent, "background selection" against slightly deleterious alleles should reduce the effective population size (ne) by orders of magnitude. for example, for a well-mixed population with 10(12) individuals and a typical level of homologous recombination (r/m = 3, i.e., nucleotide changes due to recombination [r] occu ...201526670382
novel immunomodulatory flagellin-like protein flac in campylobacter jejuni and other campylobacterales.the human diarrheal pathogens campylobacter jejuni and campylobacter coli interfere with host innate immune signaling by different means, and their flagellins, flaa and flab, have a low intrinsic property to activate the innate immune receptor toll-like receptor 5 (tlr5). we have investigated here the hypothesis that the unusual secreted, flagellin-like molecule flac present in c. jejuni, c. coli, and other campylobacterales might activate cells via tlr5 and interact with tlr5. flac shows striki ...201527303676
novel immunomodulatory flagellin-like protein flac in campylobacter jejuni and other campylobacterales.the human diarrheal pathogens campylobacter jejuni and campylobacter coli interfere with host innate immune signaling by different means, and their flagellins, flaa and flab, have a low intrinsic property to activate the innate immune receptor toll-like receptor 5 (tlr5). we have investigated here the hypothesis that the unusual secreted, flagellin-like molecule flac present in c. jejuni, c. coli, and other campylobacterales might activate cells via tlr5 and interact with tlr5. flac shows striki ...201527303676
important role of a putative lytic transglycosylase cj0843c in β-lactam resistance in campylobacter jejuni.beta-lactam antibiotics are an important class of antibiotics for treating bacterial infections. despite prevalent β-lactam resistance in campylobacter jejuni, the leading bacterial cause of human diarrhea in developed countries, molecular mechanism of β-lactam resistance in c. jejuni is still largely unknown. in this study, c. jejuni 81-176 was used for random transposon mutagenesis. screening of a 2,800-mutant library identified 22 mutants with increased susceptibility to ampicillin. of these ...201526635760
antimicrobial resistance and genotypic diversity of campylobacter isolated from pigs, dairy, and beef cattle in tanzania.foodborne campylobacter infections pose a serious threat to public health worldwide. however, the occurrence and characteristics of campylobacter in food animals and products remain largely unknown in tanzania. the objective of this study was to determine the prevalence, antibiotic resistance, and genetic profiles (sequence types, sts) of campylobacter isolated from feces of pigs and dairy and beef cattle in tanzania. overall, 259 (~30%) of 864 samples were positive for campylobacter spp, which ...201526617582
abstracts. 201526553501
abstracts. 201526553501
etiology of childhood infectious diarrhea in a developed region of china: compared to childhood diarrhea in a developing region and adult diarrhea in a developed region.in china, great differences in economy, social characteristics and hygiene exist between developing and developed regions. a comparative study of infectious diarrhea between two regions was needed. three groups of diarrheal patients were collected: children ≤5 year-olds from beijing (developed region) and henan province (developing region), and adults over 18 year-olds from beijing. a questionnaire was used to survey and feces samples were examined for 16 enteropathogens. we enrolled 1422 childr ...201526528820
multiplex detection of nine food-borne pathogens by mpcr and capillary electrophoresis after using a universal pre-enrichment medium.routine microbiological quality analyses in food samples require, in some cases, an initial incubation in pre-enrichment medium. this is necessary in order to ensure that small amounts of pathogenic strains are going to be detected. in this work, a universal pre-enrichment medium has been developed for the simultaneous growth of bacillus cereus, campylobacter jejuni, clostridium perfringens, cronobacter sakazakii, escherichia coli, enterobacteriaceae family (38 species, 27 genera), listeria mono ...201526579100
quantitative microbial risk assessment for campylobacter spp. on ham in korea.the objective of this study was to evaluate the risk of illness from campylobacter spp. on ham. to identify the hazards of campylobacter spp. on ham, the general characteristics and microbial criteria for campylobacter spp., and campylobacteriosis outbreaks were investigated. in the exposure assessment, the prevalence of campylobacter spp. on ham was evaluated, and the probabilistic distributions for the temperature of ham surfaces in retail markets and home refrigerators were prepared. in addit ...201526761897
chromosomal integration vectors allowing flexible expression of foreign genes in campylobacter jejuni.campylobacter jejuni is a major cause of human gastroenteritis yet there is limited knowledge of how disease is caused. molecular genetic approaches are vital for research into the virulence mechanisms of this important pathogen. vectors that allow expression of genes in c. jejuni via recombination onto the chromosome are particularly useful for genetic complementation of insertional knockout mutants and more generally for expression of genes in particular c. jejuni host backgrounds.201526497958
substitute sweeteners: diverse bacterial oligosaccharyltransferases with unique n-glycosylation site preferences.the central enzyme in the campylobacter jejuni asparagine-linked glycosylation pathway is the oligosaccharyltransferase (ost), pglb, which transfers preassembled glycans to specific asparagine residues in target proteins. while c. jejuni pglb (cjpglb) can transfer many diverse glycan structures, the acceptor sites that it recognizes are restricted predominantly to those having a negatively charged residue in the -2 position relative to the asparagine. here, we investigated the acceptor-site pref ...201526482295
transmission of the pabi family of restriction dna glycosylase genes: mobility and long-term inheritance.r.pabi is an exceptional restriction enzyme that functions as a dna glycosylase. the enzyme excises an unmethylated base from its recognition sequence to generate apurinic/apyrimidinic (ap) sites, and also displays ap lyase activity, cleaving the dna backbone at the ap site to generate the 3'-phospho alpha, beta-unsaturated aldehyde end in addition to the 5'-phosphate end. the resulting ends are difficult to religate with dna ligase. the enzyme was originally isolated in pyrococcus, a hypertherm ...201526481899
helicobacter pylori adaptation in vivo in response to a high-salt diet.helicobacter pylori exhibits a high level of intraspecies genetic diversity. in this study, we investigated whether the diversification of h. pylori is influenced by the composition of the diet. specifically, we investigated the effect of a high-salt diet (a known risk factor for gastric adenocarcinoma) on h. pylori diversification within a host. we analyzed h. pylori strains isolated from mongolian gerbils fed either a high-salt diet or a regular diet for 4 months by proteomic and whole-genome ...201526438795
pancreatic amylase is an environmental signal for regulation of biofilm formation and host interaction in campylobacter jejuni.campylobacter jejuni is a commensal bacterium in the intestines of animals and birds and a major cause of food-borne gastroenteritis in humans worldwide. here we show that exposure to pancreatic amylase leads to secretion of an α-dextran by c. jejuni and that a secreted protease, cj0511, is required. exposure of c. jejuni to pancreatic amylase promotes biofilm formation in vitro, increases interaction with human epithelial cell lines, increases virulence in the galleria mellonella infection mode ...201526438798
effects of nitrate addition on rumen fermentation, bacterial biodiversity and abundance.this study examined changes of rumen fermentation, ruminal bacteria biodiversity and abundance caused by nitrate addition with ion torrent sequencing and real-time polymerase chain reaction. three rumen-fistulated steers were fed diets supplemented with 0%, 1%, and 2% nitrate (dry matter %) in succession. nitrate supplementation linearly increased total volatile fatty acids and acetate concentration obviously (p = 0.02; p = 0.02; p<0.01), butyrate and isovalerate concentration numerically (p = 0 ...201526194220
core genome multilocus sequence typing scheme for high- resolution typing of enterococcus faecium.enterococcus faecium, a common inhabitant of the human gut, has emerged in the last 2 decades as an important multidrug-resistant nosocomial pathogen. since the start of the 21st century, multilocus sequence typing (mlst) has been used to study the molecular epidemiology of e. faecium. however, due to the use of a small number of genes, the resolution of mlst is limited. whole-genome sequencing (wgs) now allows for high-resolution tracing of outbreaks, but current wgs-based approaches lack stand ...201526400782
differentiation of campylobacter jejuni and campylobacter coli using multiplex-pcr and high resolution melt curve analysis.campylobacter spp. are important causes of bacterial gastroenteritis in humans in developed countries. among campylobacter spp. campylobacter jejuni (c. jejuni) and c. coli are the most common causes of human infection. in this study, a multiplex pcr (mpcr) and high resolution melt (hrm) curve analysis were optimized for simultaneous detection and differentiation of c. jejuni and c. coli isolates. a segment of the hippuricase gene (hipo) of c. jejuni and putative aspartokinase (asp) gene of c. c ...201526394042
milk modulates campylobacter invasion into caco-2 intestinal epithelial cells.raw milk is a recognized source of campylobacter outbreaks, but pasteurization is an effective way to eliminate the causative agent of campylobacteriosis. whereas breastfeeding is protective against infectious diseases, consumption of formula milk is thought to be not. however, in relation to campylobacter, such data is currently unavailable. although both pasteurized and formula milk are pathogen free and prepared in a quality controlled manner, the effect they have on the virulence of campylob ...201526495128
constitutive and inducible expression of the rrna methylase gene erm(b) in campylobacter.macrolides are the antimicrobials of choice for treating human campylobacteriosis. the recent emergence of erm(b) in campylobacter bacteria threatens the utility of this class of antibiotics. here we report the constitutive and inducible expression of erm(b) in campylobacter isolates derived from diarrheal patients and food-producing animals. constitutive expression of erm(b) was associated with insertion and deletion in the regulatory region of the gene, providing the first documentation of the ...201526259800
a metagenomic investigation of the duodenal microbiota reveals links with obesity.few studies have tested the small intestine microbiota in humans, where most nutrient digestion and absorption occur. here, our objective was to examine the duodenal microbiota between obese and normal volunteers using metagenomic techniques.201526356733
wild bird-associated campylobacter jejuni isolates are a consistent source of human disease, in oxfordshire, united kingdom.the contribution of wild birds as a source of human campylobacteriosis was investigated in oxfordshire, united kingdom (uk) over a 10 year period. the probable origin of human campylobacter jejuni genotypes, as described by multilocus sequence typing, was estimated by comparison with reference populations of isolates from farm animals and five wild bird families, using the structure algorithm. wild bird-attributed isolates accounted for between 476 (2.1%) and 543 (3.5%) cases annually. this prop ...201526109474
isolation and molecular identification of potentially pathogenic escherichia coli and campylobacter jejuni in feral pigeons from an urban area in the city of lima, peru.feral pigeons (columbia livia) live in close contact with humans and other animals. they can transmit potentially pathogenic and zoonotic agents. the objective of this study was to isolate and detect strains of diarrheagenic escherichia coli and campylobacter jejuni of urban feral pigeons from an area of lima, peru. fresh dropping samples from urban parks were collected for microbiological isolation of e. coli strains in selective agar, and campylobacter by filtration method. molecular identific ...201526603225
rapid host switching in generalist campylobacter strains erodes the signal for tracing human infections.campylobacter jejuni and campylobacter coli are the biggest causes of bacterial gastroenteritis in the developed world, with human infections typically arising from zoonotic transmission associated with infected meat. because campylobacter is not thought to survive well outside the gut, host-associated populations are genetically isolated to varying degrees. therefore, the likely origin of most strains can be determined by host-associated variation in the genome. this is instructive for characte ...201526305157
rapid host switching in generalist campylobacter strains erodes the signal for tracing human infections.campylobacter jejuni and campylobacter coli are the biggest causes of bacterial gastroenteritis in the developed world, with human infections typically arising from zoonotic transmission associated with infected meat. because campylobacter is not thought to survive well outside the gut, host-associated populations are genetically isolated to varying degrees. therefore, the likely origin of most strains can be determined by host-associated variation in the genome. this is instructive for characte ...201526305157
mass spectrometry-based phyloproteomics (mspp): a novel microbial typing method.maldi-tof-ms of microorganisms, which identifies microbes based on masses of high abundant low molecular weight proteins, is rapidly advancing to become another standard method in clinical routine laboratory diagnostics. allelic isoforms of these proteins result in varying masses of detectable biomarker ions. these variations give rise to a novel typing method for microorganisms named mass spectrometry-based phyloproteomics (mspp). the base of mspp is an amino acid sequence list of allelic isofo ...201526303099
virulence characteristics of hcp (+) campylobacter jejuni and campylobacter coli isolates from retail chicken.recently the type vi secretion system (t6ss), which can play a significant role in bacterial survival and pathogenesis, was reported in campylobacter spp., having the hcp gene as a key component.201526207145
population genetics and antimicrobial susceptibility of canine campylobacter isolates collected before and after a raw feeding experiment.in recent years, increasing numbers of consumers have become interested in feeding raw food for their pet dogs as opposed to commercial dry food, in the belief of health advantages. however, raw meat and internal organs, possibly contaminated by pathogens such as campylobacter spp., may pose a risk of transmission of zoonoses to the pet owners. campylobacter jejuni is the leading cause of bacterial gastroenteritis in humans but c. upsaliensis has also been associated with human disease. in this ...201526172151
a single nucleotide change in muty increases the emergence of antibiotic-resistant campylobacter jejuni mutants.mutator strains play an important role in the emergence of antibiotic-resistant bacteria. campylobacter jejuni is a leading cause of foodborne illnesses worldwide and is increasingly resistant to clinically important antibiotics. the objective of this study was to identify the genetic basis that contributes to a mutator phenotype in campylobacter and determine the role of this phenotype in the development of antibiotic resistance.201526169557
the contribution of co-reference resolution to supervised relation detection between bacteria and biotopes entities.the acquisition of knowledge about relations between bacteria and their locations (habitats and geographical locations) in short texts about bacteria, as defined in the bionlp-st 2013 bacteria biotope task, depends on the detection of co-reference links between mentions of entities of each of these three types. to our knowledge, no participant in this task has investigated this aspect of the situation. the present work specifically addresses issues raised by this situation: (i) how to detect the ...201526201352
filamentation of campylobacter in broth cultures.the transition from rod to filamentous cell morphology has been identified as a response to stressful conditions in many bacterial species and has been ascribed to confer certain survival advantages. filamentation of campylobacter jejuni was demonstrated to occur spontaneously on entry in to stationary phase distinguishing it from many other bacteria where a reduction in size is more common. the aim of this study was to investigate the cues that give rise to filamentation of c. jejuni and c. col ...201526175723
la35 poultry fecal marker persistence is correlated with that of indicators and pathogens in environmental waters.disposal of fecally contaminated poultry litter by land application can deliver pathogens and fecal indicator bacteria (fib) into receiving waters via runoff. while water quality is regulated by fib enumeration, fib testing provides inadequate information about contamination source and health risk. this microbial source tracking (mst) study compared the persistence of the brevibacterium sp. strain la35 16s rrna gene (marker) for poultry litter with that of pathogens and fib under outdoor, enviro ...201525934617
beyond campylobacter jejuni: understanding campylobacter coli infections in a systemic model of disease. 201526083465
comprehensive mapping of o-glycosylation in flagellin from campylobacter jejuni 11168: a multienzyme differential ion mobility mass spectrometry approach.glycosylation of flagellin is essential for the virulence of campylobacter jejuni, a leading cause of bacterial gastroenteritis. here, we demonstrate comprehensive mapping of the o-glycosylation of flagellin from campylobacter jejuni 11168 by use of a bottom-up proteomics approach that incorporates differential ion mobility spectrometry (also known as high field asymmetric waveform ion mobility spectrometry or faims) together with proteolysis with proteinase k. proteinase k provides complementar ...201525884275
narrow-spectrum inhibitors of campylobacter jejuni flagellar expression and growth.campylobacter jejuni is a major cause of food-borne illness due to its ability to reside within the gastrointestinal tracts of chickens. multiple studies have identified the flagella of c. jejuni as a major determinant of chicken colonization. an inhibitor screen of approximately 147,000 small molecules was performed to identify compounds that are able to inhibit flagellar expression in a reporter strain of c. jejuni. several compounds that modestly inhibited motility of wild-type c. jejuni in s ...201525870073
diversity of the epsilonproteobacteria dsb (disulfide bond) systems.the bacterial proteins of the dsb family-important components of the post-translational protein modification system-catalyze the formation of disulfide bridges, a process that is crucial for protein structure stabilization and activity. dsb systems play an essential role in the assembly of many virulence factors. recent rapid advances in global analysis of bacteria have thrown light on the enormous diversity among bacterial dsb systems. while the escherichia coli disulfide bond-forming system is ...201526106374
heat shock-enhanced conjugation efficiency in standard campylobacter jejuni strains.campylobacter jejuni, the leading bacterial cause of human gastroenteritis in the united states, displays significant strain diversity due to horizontal gene transfer. conjugation is an important horizontal gene transfer mechanism contributing to the evolution of bacterial pathogenesis and antimicrobial resistance. it has been observed that heat shock could increase transformation efficiency in some bacteria. in this study, the effect of heat shock on c. jejuni conjugation efficiency and the und ...201525911489
virulence genes and cytokine profile in systemic murine campylobacter coli infection.campylobacter coli are one of the most common bacteria in bacterial gastroenteritis and acute enterocolitis in humans. however, relatively little is known regarding the mechanisms of pathogenesis and host response to c. coli infections. to investigate the influence of genetic changes, we first used pcr to demonstrate the presence of the known virulence genes cadf, virb11, cdtb, cdtc and ceue in the clinical isolate c. coli 26536, which was isolated from the liver of infected balb/c mice. sequenc ...201526039573
the epidemiology and aetiology of diarrhoeal disease in infancy in southern vietnam: a birth cohort study.previous studies indicate a high burden of diarrhoeal disease in vietnamese children, however longitudinal community-based data on burden and aetiology are limited. the findings from a large, prospective cohort study of diarrhoeal disease in infants in southern vietnam are presented herein.201525813553
genetic characterization of campylobacter jejuni and c. coli isolated from broilers using flaa pcr-restriction fragment length polymorphism method in shiraz, southern iran.thermophilic campylobacters, particularly campylobacter jejuni and c. coli are the main agents of human campylobacteriosis. campylobacter contaminated chicken products is the most important source of foodborne gastroenteritis. evaluation of genetic diversity among campylobacter population is critical for understanding the epidemiology of this bacterium and developing effective control strategies against campylobacter infections and other related disorders.201526060566
a prospective multi-center observational study of children hospitalized with diarrhea in ho chi minh city, vietnam.we performed a prospective multicenter study to address the lack of data on the etiology, clinical and demographic features of hospitalized pediatric diarrhea in ho chi minh city (hcmc), vietnam. over 2,000 (1,419 symptomatic and 609 non-diarrheal control) children were enrolled in three hospitals over a 1-year period in 2009-2010. aiming to detect a panel of pathogens, we identified a known diarrheal pathogen in stool samples from 1,067/1,419 (75.2%) children with diarrhea and from 81/609 (13.3 ...201525802437
detection of multi-drug resistant escherichia coli in the urban waterways of milwaukee, wi.urban waterways represent a natural reservoir of antibiotic resistance which may provide a source of transferable genetic elements to human commensal bacteria and pathogens. the objective of this study was to evaluate antibiotic resistance of escherichia coli isolated from the urban waterways of milwaukee, wi compared to those from milwaukee sewage and a clinical setting in milwaukee. antibiotics covering 10 different families were utilized to determine the phenotypic antibiotic resistance for a ...201525972844
towards fluorescence in vivo hybridization (fivh) detection of h. pylori in gastric mucosa using advanced lna probes.in recent years, there have been several attempts to improve the diagnosis of infection caused by helicobacter pylori. fluorescence in situ hybridization (fish) is a commonly used technique to detect h. pylori infection but it requires biopsies from the stomach. thus, the development of an in vivo fish-based method (fivh) that directly detects and allows the visualization of the bacterium within the human body would significantly reduce the time of analysis, allowing the diagnosis to be performe ...201525915865
epidemiology of norovirus infections among diarrhea outpatients in a diarrhea surveillance system in shanghai, china: a cross-sectional study.norovirus is an important cause of gastroenteritis both in children and adults. in china, few studies have been conducted on adult populations. this study aimed to determine the contribution of norovirus to gastroenteritis, characterize the features of norovirus infections, compare them with other pathogens, and test the effectiveness of the surveillance system.201525884557
impact of oxidative stress defense on bacterial survival and morphological change in campylobacter jejuni under aerobic conditions.campylobacter jejuni, a microaerophilic foodborne pathogen, inescapably faces high oxygen tension during its transmission to humans. thus, the ability of c. jejuni to survive under oxygen-rich conditions may significantly impact c. jejuni viability in food and food safety as well. in this study, we investigated the impact of oxidative stress resistance on the survival of c. jejuni under aerobic conditions by examining three mutants defective in key antioxidant genes, including ahpc, kata, and so ...201525914692
multiplex polymerase chain reaction tests for detection of pathogens associated with gastroenteritis.a wide range of enteric pathogens can cause infectious gastroenteritis. conventional diagnostic algorithms are time-consuming and often lack sensitivity and specificity. advances in molecular technology have provided new clinical diagnostic tools. multiplex polymerase chain reaction (pcr)-based testing has been used in gastroenterology diagnostics in recent years. this article presents a review of recent laboratory-developed multiplex pcr tests and current commercial multiplex gastrointestinal p ...201526004652
first case report of campylobacter volucris bacteremia in an immunocompromised patient.we report a case of campylobacter volucris bacteremia in an immunocompromised patient with polycythemia vera and alcoholic liver cirrhosis. to our knowledge, this is the first case report in which this organism has been isolated from a human clinical specimen.201525832303
agriculture and food animals as a source of antimicrobial-resistant bacteria.one of the major breakthroughs in the history of medicine is undoubtedly the discovery of antibiotics. their use in animal husbandry and veterinary medicine has resulted in healthier and more productive farm animals, ensuring the welfare and health of both animals and humans. unfortunately, from the first use of penicillin, the resistance countdown started to tick. nowadays, the infections caused by antibiotic-resistant bacteria are increasing, and resistance to antibiotics is probably the major ...201525878509
coiled coil rich proteins (ccrp) influence molecular pathogenicity of helicobacter pylori.pathogenicity of the human pathogen helicobacter pylori relies on its capacity to adapt to a hostile environment and to escape the host response. although there have been great advances in our understanding of the bacterial cytoskeleton, major gaps remain in our knowledge of its contribution to virulence. in this study we have explored the influence of coiled coil rich proteins (ccrp) cytoskeletal elements on pathogenicity factors of h. pylori. deletion of any of the ccrp resulted in a strongly ...201525822999
molecular-based approaches to characterize coastal microbial community and their potential relation to the trophic state of red sea.molecular-based approaches were used to characterize the coastal microbiota and to elucidate the trophic state of red sea. nutrient content and enterococci numbers were monitored, and used to correlate with the abundance of microbial markers. microbial source tracking revealed the presence of >1 human-associated bacteroides spp. at some of the near-shore sampling sites and at a heavily frequented beach. water samples collected from the beaches had occasional exceedances in enterococci numbers, h ...201525758166
clear distinction between burkholderia mallei and burkholderia pseudomallei using fluorescent motb primers.a frame-shift mutation in the flagellum motor gene motb coding for the chemotaxis motb protein of burkholderia mallei has been utilized to design a conventional duplex pcr assay with fluorescent labelled primers.201525887130
multicenter evaluation of the bd max enteric bacterial panel pcr assay for rapid detection of salmonella spp., shigella spp., campylobacter spp. (c. jejuni and c. coli), and shiga toxin 1 and 2 genes.diarrhea due to enteric bacterial pathogens causes significant morbidity and mortality in the united states and worldwide. however, bacterial pathogens may be infrequently identified. currently, culture and enzyme immunoassays (eias) are the primary methods used by clinical laboratories to detect enteric bacterial pathogens. we conducted a multicenter evaluation of the bd max enteric bacterial panel (ebp) pcr assay in comparison to culture for the detection of salmonella spp., shigella spp., cam ...201525740779
detection of thermophilic campylobacter sp. in raw chicken sausages by methods iso 10272: 2006 in curitiba - parana state - brazil.the aim of this study was the detection of campylobacter sp. in raw chicken sausages using the methods iso 10272-1 and iso 10272-2. the overall prevalence of campylobacter sp. in the samples tested was 16.67%, representing a serious risk to the health of consumers, particularly if measures guaranteeing proper cooking of foods and prevention of cross-contamination are not adopted. furthermore, the majority of campylobacteriosis cases in humans are caused by consumption or improper handling of con ...201525763066
detection of thermophilic campylobacter sp. in raw chicken sausages by methods iso 10272: 2006 in curitiba - parana state - brazil.the aim of this study was the detection of campylobacter sp. in raw chicken sausages using the methods iso 10272-1 and iso 10272-2. the overall prevalence of campylobacter sp. in the samples tested was 16.67%, representing a serious risk to the health of consumers, particularly if measures guaranteeing proper cooking of foods and prevention of cross-contamination are not adopted. furthermore, the majority of campylobacteriosis cases in humans are caused by consumption or improper handling of con ...201525763066
genome comparison provides molecular insights into the phylogeny of the reassigned new genus lysinibacillus.lysinibacillus sphaericus (formerly named bacillus sphaericus) is incapable of polysaccharide utilization and some isolates produce active insecticidal proteins against mosquito larvae. its taxonomic status was changed to the genus lysinibacillus in 2007 with some other organisms previously regarded as members of bacillus. however, this classification is mainly based on physiology and phenotype and there is limited genomic information to support it.201525888315
environmental monitoring of waterborne campylobacter: evaluation of the australian standard and a hybrid extraction-free mpn-pcr method.campylobacter is the leading agent of diarrheal disease worldwide. this study evaluates a novel culture-pcr hybrid (mpn-pcr) assay for the rapid enumeration of campylobacter spp. from estuarine and wastewater systems. to first evaluate the current, culture-based, australian standard, an inter-laboratory study was conducted on 69 subsampled water samples. the proposed most-probable number (mpn)-pcr method was then evaluated, by analysing 147 estuarine samples collected over a 2 year period. data ...201525709604
structural and functional implications of the interaction between macrolide antibiotics and bile acids.macrolide antibiotics, such as azithromycin and erythromycin, are in widespread use for the treatment of bacterial infections. macrolides are taken up and excreted mainly by bile. additionally, they have been implicated in biliary system diseases and to modify the excretion of other drugs through bile. despite mounting evidence for the interplay between macrolide antibiotics and bile acids, the molecular details of this interaction remain unknown. herein, we show by nmr measurements that macroli ...201525655041
comparison of eleven methods for genomic dna extraction suitable for large-scale whole-genome genotyping and long-term dna banking using blood samples.over the recent years, next generation sequencing and microarray technologies have revolutionized scientific research with their applications to high-throughput analysis of biological systems. isolation of high quantities of pure, intact, double stranded, highly concentrated, not contaminated genomic dna is prerequisite for successful and reliable large scale genotyping analysis. high quantities of pure dna are also required for the creation of dna-banks. in the present study, eleven different d ...201525635817
microbial contamination of drinking water and human health from community water systems.a relatively short list of reference viral, bacterial and protozoan pathogens appears adequate to assess microbial risks and inform a system-based management of drinking waters. nonetheless, there are data gaps, e.g. human enteric viruses resulting in endemic infection levels if poorly performing disinfection and/or distribution systems are used, and the risks from fungi. where disinfection is the only treatment and/or filtration is poor, cryptosporidiosis is the most likely enteric disease to b ...201525821716
a community-based gastroenteritis outbreak after typhoon haiyan, leyte, philippines, 2013.three weeks after typhoon haiyan, an increasing number of acute gastroenteritis cases were reported in kananga, leyte, an area where evacuated residents had returned home two days after the disaster. an outbreak investigation was conducted to identify the source and risk factors associated with the increase of gastroenteritis.201525960917
prevalence of campylobacter species in milk and milk products, their virulence gene profile and anti-bio gram.during the last decades, number of food poisoning cases due to campylobacter occurred, immensely. after poultry, raw milk acts as a second main source of campylobacter. therefore, the present study was undertaken to detect the prevalence of campylobacters in milk and milk products and to know the antibiotic sensitivity and virulence gene profile of campylobacter spp. in anand city, gujarat, india.201527046986
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