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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
laboratory diagnosis of bacterial gastroenteritis.bacterial gastroenteritis is a disease that is pervasive in both the developing and developed worlds. while for the most part bacterial gastroenteritis is self-limiting, identification of an etiological agent by bacterial stool culture is required for the management of patients with severe or prolonged diarrhea, symptoms consistent with invasive disease, or a history that may predict a complicated course of disease. importantly, characterization of bacterial enteropathogens from stool cultures i ...201525567220
differential distribution of type ii crispr-cas systems in agricultural and nonagricultural campylobacter coli and campylobacter jejuni isolates correlates with lack of shared environments.crispr (clustered regularly interspaced palindromic repeats)-cas (crispr-associated) systems are sequence-specific adaptive defenses against phages and plasmids which are widespread in prokaryotes. here we have studied whether phylogenetic relatedness or sharing of environmental niches affects the distribution and dissemination of type ii crispr-cas systems, first in 132 bacterial genomes from 15 phylogenetic classes, ranging from proteobacteria to actinobacteria. there was clustering of distinc ...201526338188
the challenge of efflux-mediated antibiotic resistance in gram-negative bacteria.the global emergence of multidrug-resistant gram-negative bacteria is a growing threat to antibiotic therapy. the chromosomally encoded drug efflux mechanisms that are ubiquitous in these bacteria greatly contribute to antibiotic resistance and present a major challenge for antibiotic development. multidrug pumps, particularly those represented by the clinically relevant acrab-tolc and mex pumps of the resistance-nodulation-division (rnd) superfamily, not only mediate intrinsic and acquired mult ...201525788514
[identification of zoonotic bacterial pathogens by the maldi tof ms method].to verify whether the maldi tof ms method can be used for rapid identification of selected zoonotic bacterial pathogens isolated from various types of materials in the real conditions of routine laboratory work.201526312374
the polar and lateral flagella from plesiomonas shigelloides are glycosylated with legionaminic acid.plesiomonas shigelloides is the unique member of the enterobacteriaceae family able to produce polar flagella when grow in liquid medium and lateral flagella when grown in solid or semisolid media. in this study on p. shigelloides 302-73 strain, we found two different gene clusters, one exclusively for the lateral flagella biosynthesis and the other one containing the biosynthetic polar flagella genes with additional putative glycosylation genes. p. shigelloides is the first enterobacteriaceae w ...201526167161
bacterial flagella: twist and stick, or dodge across the kingdoms.the flagellum organelle is an intricate multiprotein assembly best known for its rotational propulsion of bacteria. however, recent studies have expanded our knowledge of other functions in pathogenic contexts, particularly adherence and immune modulation, e.g., for salmonella enterica, campylobacter jejuni, pseudomonas aeruginosa, and escherichia coli. flagella-mediated adherence is important in host colonisation for several plant and animal pathogens, but the specific interactions that promote ...201525590430
detection of mycobacteria, mycobacterium avium subspecies, and mycobacterium tuberculosis complex by a novel tetraplex real-time pcr assay.mycobacterium tuberculosis complex, mycobacterium avium, and many other nontuberculous mycobacteria are worldwide distributed microorganisms of major medical and veterinary importance. considering the growing epidemiologic significance of wildlife-livestock-human interrelation, developing rapid detection tools of high specificity and sensitivity is vital to assess their presence and accelerate the process of diagnosing mycobacteriosis. here we describe the development and evaluation of a novel t ...201525588660
functional metagenomics of spacecraft assembly cleanrooms: presence of virulence factors associated with human pathogens.strict planetary protection practices are implemented during spacecraft assembly to prevent inadvertent transfer of earth microorganisms to other planetary bodies. therefore, spacecraft are assembled in cleanrooms, which undergo strict cleaning and decontamination procedures to reduce total microbial bioburden. we wanted to evaluate if these practices selectively favor survival and growth of hardy microorganisms, such as pathogens. three geographically distinct cleanrooms were sampled during the ...201627667984
simultaneous identification of 13 foodborne pathogens by using capillary electrophoresis-single strand conformation polymorphism coupled with multiplex ligation-dependent probe amplification and its application in foods.capillary electrophoresis-single strand conformation polymorphism (ce-sscp) coupled with stuffer-free multiplex ligation-dependent probe amplification (mlpa) was developed to identify 13 species of foodborne pathogens simultaneously. species-specific mlpa probes were designed for nine of these species. these probes were targeted to the groel, glya, mms, tuf, inv, ipah, nuc, vvh, and 16s rrna genes, which corresponded to bacillus cereus, campylobacter coli, cronobacter sakazakii, enterococcus spp ...201627494415
a rapid and simple real-time pcr assay for detecting foodborne pathogenic bacteria in human feces.a rapid, simple method for detecting foodborne pathogenic bacteria in human feces is greatly needed. here, we examined the efficacy of a method that employs a combination of a commercial pcr master mix, which is insensitive to pcr inhibitors, and a dna extraction method which used sodium dodecyl benzene sulfonate (sdbs), and tween 20 to counteract the inhibitory effects of sdbs on the pcr assay. this method could detect the target genes (stx1 and stx2 of enterohemorrhagic escherichia coli, inva ...201626902211
multidrug-resistant campylobacter coli in men who have sex with men, quebec, canada, 2015. 201627533504
systematic site-directed mutagenesis of the helicobacter pylori cagl protein of the cag type iv secretion system identifies novel functional domains.the cag type iv secretion system, which contributes to inflammation and cancerogenesis during chronic infection, is one of the major virulence factors of the bacterial gastric pathogen helicobacter pylori. we have generated and characterized a series of non-marked site-directed chromosomal mutants in h. pylori to define domains of unknown function of the essential tip protein cagl of the cag secretion system. characterizing the cagl mutants, we determined that their function to activate cells an ...201627922023
isolation of campylobacter spp. from client-owned dogs and cats, and retail raw meat pet food in the manawatu, new zealand.campylobacter causes acute gastroenteritis in people worldwide and is frequently isolated from food, animals and the environment. the disease is predominately food-borne but many routes of transmission and sources of infection have been described, including contact with pets. the prevalence of campylobacter spp. in dogs and cats varies widely, and data on new zealand pets are limited. this study aimed to investigate the prevalence of campylobacter spp. in dogs, cats and retail raw meat pet food ...201627860343
variation in campylobacter multilocus sequence typing subtypes from chickens as detected on three plating media.the objective of this study was to compare subtypes of campylobacter jejuni and campylobacter coli detected on three selective campylobacter plating media to determine whether each medium selected for different subtypes. fifty ceca and 50 carcasses (representing 50 flocks) were collected from the evisceration line in a commercial broiler processing plant. campylobacter was cultured and isolated from cecal contents and carcass rinses on campy-cefex, campy line, and rf campylobacter jejuni/coli ag ...201628221919
prevalence of thermotolerant campylobacter spp. in chicken meat in croatia and multilocus sequence typing of a small subset of campylobacter jejuni and campylobacter coli isolates.in order to detect thermotolerant campylobacter spp., 241 samples of fresh chicken meat, at retail in croatia, were analysed according to a standard method, followed by biochemical test and molecular polymerase chain reaction/restriction enzyme analysis for exact species determination. campylobacter spp. prevalence was 73.86%. campylobacter jejuni and campylobacter coli were isolated from 53.53 and 15.35% of the samples, respectively. in 4.98% of isolates thermotolerant campylobacter spp. were n ...201628115906
restriction glycosylases: involvement of endonuclease activities in the restriction process.all restriction enzymes examined are phosphodiesterases generating 3'-oh and 5'-p ends, but one restriction enzyme (restriction glycosylase) excises unmethylated bases from its recognition sequence. whether its restriction activity involves endonucleolytic cleavage remains unclear. one report on this enzyme, r.pabi from a hyperthermophile, ascribed the breakage to high temperature while another showed its weak ap lyase activity generates atypical ends. here, we addressed this issue in mesophiles ...201627980098
identification of a campylobacter coli methyltransferase targeting adenines at gatc sites.campylobacter coli can infect humans and colonize multiple other animals but its host-associated genes or adaptations are poorly understood. adenine methylation at gatc sites, resulting in mboi resistance of genomic dna, was earlier frequently detected among c. coli from swine but not among turkey-derived isolates. the underlying genetic basis has remained unknown. comparative genome sequence analyses of c. coli 6461, a swine-derived strain with mboi-resistant dna, revealed two chromosomal orfs, ...201627915251
genomic variations leading to alterations in cell morphology of campylobacter spp.campylobacter jejuni, the most common cause of bacterial diarrhoeal disease, is normally helical. however, it can also adopt straight rod, elongated helical and coccoid forms. studying how helical morphology is generated, and how it switches between its different forms, is an important objective for understanding this pathogen. here, we aimed to determine the genetic factors involved in generating the helical shape of campylobacter. a c. jejuni transposon (tn) mutant library was screened for non ...201627910897
large sequence diversity within the biosynthesis locus and common biochemical features of campylobacter coli lipooligosaccharides.despite the importance of lipooligosaccharides (loss) in the pathogenicity of campylobacteriosis, little is known about the genetic and phenotypic diversity of los in campylobacter coli in this study, we investigated the distribution of los locus classes among a large collection of unrelated c. coli isolates sampled from several different host species. furthermore, we paired c. coli genomic information and los chemical composition for the first time to investigate possible associations between l ...201627481928
influence of enrichment and isolation media on the detection of campylobacter spp. in naturally contaminated chicken samples.investigating campylobacter epidemiology requires adequate technique and media to ensure optimal culturing and accurate detection and isolation of campylobacter strains. in the present study, we investigated the performances of three enrichment durations in bolton broth (0, 24 and 48h) and compared four isolation media (mccda, karmali, butzler no. 2 and campyfood agar (cfa)) for the detection of campylobacter positive samples and the identification of campylobacter species, from naturally contam ...201627373751
clinical relevance of infections with zoonotic and human oral species of campylobacter.genus campylobacter has been recognized as a causative bacterial agent of animal and human diseases. human campylobacter infections have caused more concern. campylobacters can be classified into two groups in terms of their original host: zoonotic and human oral species. the major zoonotic species are campylobacter jejuni and campylobacter coli, which mostly reside in the intestines of avian species and are transmitted to humans via consumption of contaminated poultry products, thus causing hum ...201627350611
monitoring antimicrobial resistance in the food supply chain and its implications for fda policy initiatives.in response to concerning increases in antimicrobial resistance (amr), the food and drug administration (fda) has decided to increase veterinary oversight requirements for antimicrobials and restrict their use in growth promotion. given the high stakes of this policy for the food supply, economy, and human and veterinary health, it is important to rigorously assess the effects of this policy. we have undertaken a detailed analysis of data provided by the national antimicrobial resistance monitor ...201627324772
evaluation of a multiplex real-time pcr assay for detecting major bacterial enteric pathogens in fecal specimens: intestinal inflammation and bacterial load are correlated in campylobacter infections.a total of 1,056 native or cary-blair-preserved stool specimens were simultaneously tested by conventional stool culturing and by enteric bacterial panel (ebp) multiplex real-time pcr for campylobacter jejuni, campylobacter coli, salmonella spp., and shigellosis disease-causing agents (shigella spp. and enteroinvasive escherichia coli [eiec]). overall, 143 (13.5%) specimens tested positive by pcr for the targets named above; 3 coinfections and 109 (10.4%) campylobacter spp., 17 (1.6%) salmonella ...201627307458
quantifying potential sources of surface water contamination with campylobacter jejuni and campylobacter coli.campylobacter is the most common causative agent of human bacterial gastroenteritis and is frequently found in surface water, where it indicates recent contamination with animal faeces, sewage effluent, and agricultural run-off. the contribution of different animal reservoirs to surface water contamination with campylobacter is largely unknown. in the netherlands, the massive poultry culling to control the 2003 avian influenza epidemic coincided with a 44-50% reduction in human campylobacteriosi ...201627244295
multilocus sequence typing of campylobacter jejuni and campylobacter coli isolates from poultry, cattle and humans in nigeria.to determine the genetic diversity of campylobacter jejuni and campylobacter coli isolates from nigeria and to identify the association between multilocus sequence types and hosts (poultry, cattle and humans).201627206561
functional genomics in campylobacter coli identified a novel streptomycin resistance gene located in a hypervariable genomic region.numerous aminoglycoside resistance genes have been reported in campylobacter spp. often resembling those from gram-positive bacterial species and located in transferable genetic elements with other resistance genes. we discovered a new streptomycin (str) resistance gene in campylobactercoli showing 27-34 % amino acid identity to aminoglycoside 6-nucleotidyl-transferases described previously in campylobacter. str resistance was verified by gene expression and insertional inactivation. this ant-li ...201627154456
l-fucose influences chemotaxis and biofilm formation in campylobacter jejuni.campylobacter jejuni and campylobacter coli are zoonotic pathogens once considered asaccharolytic, but are now known to encode pathways for glucose and fucose uptake/metabolism. for c. jejuni, strains with the fuc locus possess a competitive advantage in animal colonization models. we demonstrate that this locus is present in > 50% of genome-sequenced strains and is prevalent in livestock-associated isolates of both species. to better understand how these campylobacters sense nutrient availabili ...201627145048
antibiotic resistance and polymorphism in the quinolone resistance-determining region of campylobacter spp. isolated from 1-day-old ducklings.thirty-three isolates of campylobacter coli and three isolates of campylobacter jejuni were recovered from 150 1-day-old ducklings. all isolates were sensitive to chloramphenicol and amikacin, but resistant to sulfamethoxazole-trimethoprim (sxt) by the disc diffusion method. most isolates were susceptible to tetracycline and erythromycin, but resistant to ofloxacin and ciprofloxacin. of the 33 c. coli isolates, nine were positive for the tetracycline resistance gene tet(o), although only two of ...201627068149
combined campylobacter jejuni and campylobacter coli rapid testing and molecular epidemiology in conventional broiler flocks.campylobacter spp. are important causes of bacterial zoonosis, most often transmitted by contaminated poultry meat. from an epidemiological and risk assessment perspective, further knowledge should be obtained on campylobacter prevalence and genotype distribution in primary production. consequently, 15 austrian broiler flocks were surveyed in summer for their thermophilic campylobacter spp. contamination status. chicken droppings, dust and drinking water samples were collected from each flock at ...201627061601
molecular subtyping and erythromycin resistance of campylobacter in china.to investigate the erythromycin resistance patterns and mechanism for campylobacter isolates in china.201626999516
discriminative power of campylobacter phenotypic and genotypic typing methods.the aim of this study was to compare different typing methods, individually and combined, for use in the monitoring of campylobacter in food. campylobacter jejuni (n=94) and campylobacter coli (n=52) isolated from different broiler meat carcasses were characterized using multilocus sequence typing (mlst), flagellin gene a restriction fragment length polymorphism typing (flaa-rflp), antimicrobial resistance profiling (amrp), the presence/absence of 5 putative virulence genes; and, exclusively for ...201626996762
influence of commercial laying hen housing systems on the incidence and identification of salmonella and campylobacter.the housing of laying hens is important for social, industrial, and regulatory aspects. many studies have compared hen housing systems on the research farm, but few have fully examined commercial housing systems and management strategies. the current study compared hens housed in commercial cage-free aviary, conventional cage, and enriched colony cage systems. environmental and eggshell pool samples were collected from selected cages/segments of the housing systems throughout the production cycl ...201626976901
the effects of 405-nm visible light on the survival of campylobacter on chicken skin and stainless steel.campylobacter spp. are foodborne pathogens responsible for a significant portion of human cases of bacterial-mediated gastrointestinal disease. a primary method for the introduction of campylobacter into the food supply is through poultry products. reducing the number of campylobacter on poultry products may reduce the incidence of human disease. research has been conducted on the use of light to inactivate campylobacter on poultry products and processing environments. more recently, the use of ...201626938455
isolation, identification and antibiotic resistance of campylobacter strains isolated from domestic and free-living pigeons.1. the aim of this study was to evaluate the occurrence of campylobacter spp. in domestic and free-living pigeons and to evaluate the antibiotic resistance profiles. 2. the material consisted of cloacal swabs obtained from 108 homing pigeons and fresh faeces from 72 wild birds from lublin and its vicinity. the identification of strains isolated on differential/selective media for campylobacter spp. was carried out by maldi-tof and pcr. the susceptibility to antibiotics was evaluated by minimum i ...201626841300
characterization of antimicrobial susceptibility and its association with virulence genes related to adherence, invasion, and cytotoxicity in campylobacter jejuni and campylobacter coli isolates from animals, meat, and humans.the aim of this research was to statistically analyze the association between antimicrobial susceptibility/resistance to erythromycine, gentamicin, ciprofloxacin, and tetracycline and 11 virulence genes associated with adherence, invasion, and cytotoxicity in 528 isolates of campylobacter coli and campylobacter jejuni obtained from retail meat and fecal samples from food-producing animals and human patients. a high percentage of campylobacter strains were resistant to antimicrobials, specificall ...201626779841
zoonotic public health hazards in backyard chickens.backyard poultry has become increasingly popular in industrialized countries. in addition to keeping chickens for eggs and meat, owners often treat the birds as pets. however, several pathogenic enteric bacteria have the potential for zoonotic transmission from poultry to humans but very little is known about the occurrence of zoonotic pathogens in backyard flocks. the occurrence and the antimicrobial resistance of salmonella enterica, campylobacter spp., listeria monocytogenes and enteropathoge ...201626752227
evaluation of a protective effect of in ovo delivered campylobacter jejuni omvs.campylobacter jejuni is the most prevalent cause of a food-borne gastroenteritis in the developed world, with poultry being the main source of infection. campylobacter jejuni, like other gram-negative bacteria, constitutively releases outer membrane vesicles (omvs). omvs are highly immunogenic, can be taken up by mammalian cells, and are easily modifiable by recombinant engineering. we have tested their usefulness for an oral (in ovo) vaccination of chickens. four groups of 18-day-old chicken em ...201627383607
what makes a bacterial species pathogenic?:comparative genomic analysis of the genus leptospira.leptospirosis, caused by spirochetes of the genus leptospira, is a globally widespread, neglected and emerging zoonotic disease. while whole genome analysis of individual pathogenic, intermediately pathogenic and saprophytic leptospira species has been reported, comprehensive cross-species genomic comparison of all known species of infectious and non-infectious leptospira, with the goal of identifying genes related to pathogenesis and mammalian host adaptation, remains a key gap in the field. in ...201626890609
accuracy of commercial kits and published primer pairs for the detection of periodontopathogens.despite the input of microbiome research, a group of 20 bacteria continues to be the focus of periodontal diagnostics and therapy. the aim of this study was to compare three commercial kits and laboratory-developed primer pairs for effectiveness in detecting such periodontopathogens.201627020914
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