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association of clustered regularly interspaced short palindromic repeat (crispr) elements with specific serotypes and virulence potential of shiga toxin-producing escherichia coli.shiga toxin-producing escherichia coli (stec) strains (n = 194) representing 43 serotypes and e. coli k-12 were examined for clustered regularly interspaced short palindromic repeat (crispr) arrays to study genetic relatedness among stec serotypes. a subset of the strains (n = 81) was further analyzed for subtype i-e cas and virulence genes to determine a possible association of crispr elements with potential virulence. four types of crispr arrays were identified. crispr1 and crispr2 were presen ...201424334663
development of duplex pcr assay for detection and differentiation of typical and atypical melissococcus plutonius strains.melissococcus plutonius is the causative agent of an important honeybee disease, european foulbrood (efb). in addition to m. plutonius strains with typical characteristics (typical m. plutonius), we recently reported the presence of atypical m. plutonius, which are phenotypically and genetically distinguished from typical m. plutonius. because typical and atypical m. plutonius may have different pathogenic mechanisms, differentiation of these two types is very important for diagnosis and more ef ...201324334815
development of duplex pcr assay for detection and differentiation of typical and atypical melissococcus plutonius strains.melissococcus plutonius is the causative agent of an important honeybee disease, european foulbrood (efb). in addition to m. plutonius strains with typical characteristics (typical m. plutonius), we recently reported the presence of atypical m. plutonius, which are phenotypically and genetically distinguished from typical m. plutonius. because typical and atypical m. plutonius may have different pathogenic mechanisms, differentiation of these two types is very important for diagnosis and more ef ...201324334815
report of ribosomal rna methylase gene erm(b) in multidrug-resistant campylobacter coli.campylobacter is a major foodborne enteric pathogen and macrolides are the drug of choice for the clinical therapy of campylobacteriosis. macrolide resistance among campylobacter compromises clinical treatment, is associated with adverse health events and is a significant public health concern. here, we report the first identification of a horizontally transferrable macrolide resistance mechanism in porcine campylobacter coli zc113 that is mediated by a ribosomal rna methylase, erm(b).201424335515
complete genome sequence of the campylobacter coli clinical isolate 15-537360.campylobacter coli strain 15-537360 was originally isolated in 2001 from a 42-year-old patient with gastroenteritis. here, we report its complete genome sequence, which comprises a 1.7-mbp chromosome and a 29-kbp conjugative cryptic plasmid. this is the first complete genome sequence of a clinical isolate of c. coli.201324336384
guillain barre syndrome as a manifestation of neurological melioidosis.neurological melioidosis is a very rare and very few cases have been reported from india. presentation is an extremely varied and as this disease is associated with high mortality, high index of suspicion is needed to diagnose and treat. in this context, we report a patient presenting as guillain barre syndrome evaluated as melioidosis.201324339608
a case of acute motor and sensory axonal neuropathy following hepatitis a infection.acute motor and sensory axonal neuropathy (amsan) are recently described subtypes of guillain-barre syndrome characterized by acute onset of distal weakness, loss of deep tendon reflexes, and sensory symptoms. a 21-yr-old male was transferred to our hospital due to respiration difficulties and progressive weakness. in laboratory findings, immunoglobulin m antibodies against hepatitis a were detected in blood and cerebrospinal fluid. the findings of motor nerve conduction studies showed markedly ...201324339719
humans and cattle: a review of bovine zoonoses.infectious disease prevention and control has been among the top public health objectives during the last century. however, controlling disease due to pathogens that move between animals and humans has been challenging. such zoonotic pathogens have been responsible for the majority of new human disease threats and a number of recent international epidemics. currently, our surveillance systems often lack the ability to monitor the human-animal interface for emergent pathogens. identifying and ult ...201424341911
consumption of raw or unpasteurized milk and milk products by pregnant women and children.sales of raw or unpasteurized milk and milk products are still legal in at least 30 states in the united states. raw milk and milk products from cows, goats, and sheep continue to be a source of bacterial infections attributable to a number of virulent pathogens, including listeria monocytogenes, campylobacter jejuni, salmonella species, brucella species, and escherichia coli o157. these infections can occur in both healthy and immunocompromised individuals, including older adults, infants, youn ...201424344105
[ill after drinking untreated milk; 'die amelander krankheit'].in 2012 three patients consulted their general practitioner with symptoms of gastro-enteritis with bloody stools. this was caused by drinking untreated milk infected with campylobacter jejuni. another patient developed reactive arthritis. he too had drunk untreated milk that had probably been infected with yersinia enterocolitica. between 1958 and 1995 many german children living in the region of cologne developed gastro-enteritis after holidaying on ameland, one of the dutch islands. this condi ...201324345367
use of in vivo-induced antigen technology to identify in vivo-expressed genes of campylobacter jejuni during human infection.campylobacter jejuni is a prevalent foodborne pathogen worldwide. human infection by c. jejuni primarily arises from contaminated poultry meats. genes expressed in vivo may play an important role in the pathogenicity of c. jejuni. we applied an immunoscreening method, in vivo-induced antigen technology (iviat), to identify in vivo-induced genes during human infection by c. jejuni. an inducible expression library of genomic proteins was constructed from sequenced c. jejuni nctc 11168 and was then ...201424346471
three-dimensional structure of a sugar n-formyltransferase from francisella tularensis.n-formylated sugars have been observed on the o-antigens of such pathogenic gram-negative bacteria as campylobacter jejuni and francisella tularensis. until recently, however, little was known regarding the overall molecular architectures of the n-formyltransferases that are required for the biosynthesis of these unusual sugars. here we demonstrate that the protein encoded by the wbtj gene from f. tularensis is an n-formyltransferase that functions on dtdp-4-amino-4,6-dideoxy-d-glucose as its su ...201424347283
crispr-cas immunity against phages: its effects on the evolution and survival of bacterial pathogens. 201324348245
exploring the risks of phage application in the environment.interest in using bacteriophages to control the growth and spread of bacterial pathogens is being revived in the wake of widespread antibiotic resistance. however, little is known about the ecological effects that high concentrations of phages in the environment might have on natural microbial communities. we review the current evidence suggesting phage-mediated environmental perturbation, with a focus on agricultural examples, and describe the potential implications for human health and agricul ...201324348468
transabdominal ultrasonography of the small bowel.in the era of double balloon enteroscopy, capsule endoscopy, ct, and mri enterography is transabdominal ultrasonography (tus) underestimated method for evaluation of small bowel pathology. as often initial imagine method in abdominal complaints, nowadays has tus much better diagnostic potential than two decades ago. high-resolution ultrasound probes with harmonic imaging significantly improve resolution of bowel wall in real time, with possibility to asses bowel peristalsis. color flow doppler e ...201324348544
nationwide surveillance for pathogenic microorganisms in groundwater near carcass burials constructed in south korea in 2010.widespread outbreaks of foot-and-mouth disease and avian influenza occurred in south korea during 2010. in response to the culling of many animals to attenuate the spread of disease, south korea used mass burial sites to dispose of the large number of carcasses; consequently, concerns about groundwater contamination by leachate from these burial sites are increasing. groundwater is one of the main sources of drinking water, and its cleanliness is directly related to public health. thus, this stu ...201324351737
the potential link between gut microbiota and ige-mediated food allergy in early life.there has been a dramatic rise in the prevalence of ige-mediated food allergy over recent decades, particularly among infants and young children. the cause of this increase is unknown but one putative factor is a change in the composition, richness and balance of the microbiota that colonize the human gut during early infancy. the coevolution of the human gastrointestinal tract and commensal microbiota has resulted in a symbiotic relationship in which gut microbiota play a vital role in early li ...201324351744
guillain-barré syndrome in asia.over the past 20 years, the most notable advance in understanding guillain-barré syndrome (gbs) has been the identification of an axonal variant. this advance arose chiefly through studies undertaken in east asian countries and comprised two major aspects: first, the immunopathogenesis of axonal gbs related to anti-ganglioside antibodies and molecular mimicry of campylobacter jejuni; and second, the observation that distinct electrophysiological patterns of axonal gbs existed, reflecting reversi ...201424357682
citrobacter infection and wnt signaling.gut flora generally contributes to a healthy environment while both commensal and pathogenic bacteria that influence the innate and adaptive immune responses, can cause acute and/or chronic mucosal inflammation. citrobacter rodentium (c. rodentium) is a member of the family of enteropathogens that provide an excellent in vivo model to investigate the host-pathogen interactions in real-time. it is the etiologic agent for transmissible murine colonic hyperplasia (tmch) while inflammation following ...201224358033
antibodies to heteromeric glycolipid complexes in guillain-barré syndrome.autoantibodies are infrequently detected in the sera of patients with the demyelinating form of guillain-barré syndrome most commonly encountered in the western world, despite abundant circumstantial evidence suggesting their existence. we hypothesised that antibody specificities reliant on the cis interactions of neighbouring membrane glycolipids could explain this discrepancy, and would not have been detected by traditional serological assays using highly purified preparations of single gangli ...201324358172
molecular diagnosis of arcobacter and campylobacter in diarrhoeal samples among portuguese patients.the present study was conducted to investigate the prevalence and diversity of arcobacter and campylobacter spp. in 298 stool samples of patients with diarrhoea, collected from 22 portuguese hospitals, between september and november 2012. detection of arcobacter and campylobacter spp. was performed using molecular-based detection techniques, such as real-time fluorescence resonance energy transfer pcr, species-specific pcr, and sequencing of amplified pcr products. overall, 1.3% of the samples w ...201424361090
age-related shifts in the density and distribution of genetic marker water quality indicators in cow and calf feces.calves make up about 16% of the current bovine population in the united states and can excrete high levels of human pathogens in their feces. we describe the density and distribution of genetic markers from 9 pcr- and real-time quantitative pcr-based assays, including cf128, cf193, cowm2, cowm3, genbac3, entero1, ec23s857, campf2, and ttr-6, commonly used to help assess ambient surface water quality. each assay was tested against a collection of 381 individual bovine fecal samples representing 3 ...201424362434
invasion of epithelial cells by campylobacter jejuni is independent of caveolae.caveolae are 25-100 nm flask-like membrane structures enriched in cholesterol and glycosphingolipids. researchers have proposed that campylobacter jejuni require caveolae for cell invasion based on the finding that treatment of cells with the cholesterol-depleting compounds filipin iii or methyl-β-cyclodextrin (mβcd) block bacterial internalization in a dose-dependent manner. the purpose of this study was to determine the role of caveolae and caveolin-1, a principal component of caveolae, in c. ...201324364863
a unique in vivo experimental approach reveals metabolic adaptation of the probiotic propionibacterium freudenreichii to the colon environment.propionibacterium freudenreichii is a food grade bacterium consumed both in cheeses and in probiotic preparations. its promising probiotic potential, relying largely on the active release of beneficial metabolites within the gut as well as the expression of key surface proteins involved in immunomodulation, deserves to be explored more deeply. adaptation to the colon environment is requisite for the active release of propionibacterial beneficial metabolites and constitutes a bottleneck for metab ...201324365073
the nod1, nod2, and rip2 axis contributes to host immune defense against intracellular acinetobacter baumannii infection.acinetobacter baumannii is a major extensively drug-resistant lethal human nosocomial bacterium. however, the host innate immune mechanisms controlling a. baumannii are not well understood. although viewed as an extracellular pathogen, a. baumannii can also invade and survive intracellularly. however, whether host innate immune pathways sensing intracellular bacteria contribute to immunity against a. baumannii is not known. here, we provide evidence for the first time that intracellular antibact ...201424366254
effects of genotypic and phenotypic variation on establishment are important for conservation, invasion, and infection biology.there is abundant evidence that the probability of successful establishment in novel environments increases with number of individuals in founder groups and with number of repeated introductions. theory posits that the genotypic and phenotypic variation among individuals should also be important, but few studies have examined whether founder diversity influences establishment independent of propagule pressure, nor whether the effect is model or context dependent. i summarize the results of 18 ex ...201324367109
effects of genotypic and phenotypic variation on establishment are important for conservation, invasion, and infection biology.there is abundant evidence that the probability of successful establishment in novel environments increases with number of individuals in founder groups and with number of repeated introductions. theory posits that the genotypic and phenotypic variation among individuals should also be important, but few studies have examined whether founder diversity influences establishment independent of propagule pressure, nor whether the effect is model or context dependent. i summarize the results of 18 ex ...201324367109
antibiotic development challenges: the various mechanisms of action of antimicrobial peptides and of bacterial resistance.antimicrobial peptides (amps) are natural antibiotics produced by various organisms such as mammals, arthropods, plants, and bacteria. in addition to antimicrobial activity, amps can induce chemokine production, accelerate angiogenesis, and wound healing and modulate apoptosis in multicellular organisms. originally, their antimicrobial mechanism of action was thought to consist solely of an increase in pathogen cell membrane permeability, but it has already been shown that several amps do not mo ...201324367355
common themes and unique proteins for the uptake and trafficking of nickel, a metal essential for the virulence of helicobacter pylori.nickel is a virulence determinant for the human gastric pathogen helicobacter pylori. indeed, h. pylori possesses two nickel-enzymes that are essential for in vivo colonization, [nife] hydrogenase and urease, an abundant virulence factor that contains 24 nickel ions per active complex. because of these two enzymes, survival of h. pylori relies on an important supply of nickel, implying a tight control of its distribution and storage. in this review, we will present the pathways of activation of ...201324367767
the role of microbiome in central nervous system disorders.mammals live in a co-evolutionary association with the plethora of microorganisms that reside at a variety of tissue microenvironments. the microbiome represents the collective genomes of these co-existing microorganisms, which is shaped by host factors such as genetics and nutrients but in turn is able to influence host biology in health and disease. niche-specific microbiome, prominently the gut microbiome, has the capacity to effect both local and distal sites within the host. the gut microbi ...201324370461
the role of microbiome in central nervous system disorders.mammals live in a co-evolutionary association with the plethora of microorganisms that reside at a variety of tissue microenvironments. the microbiome represents the collective genomes of these co-existing microorganisms, which is shaped by host factors such as genetics and nutrients but in turn is able to influence host biology in health and disease. niche-specific microbiome, prominently the gut microbiome, has the capacity to effect both local and distal sites within the host. the gut microbi ...201324370461
protein selection and export via outer membrane vesicles.outer membrane vesicles (omvs) are constitutively produced by all gram-negative bacteria. omvs form when buds from the outer membrane (om) of cells encapsulate periplasmic material and pinch off from the om to form spheroid particles approximately 10 to 300nm in diameter. omvs accomplish a diversity of functional roles yet the omv's utility is ultimately determined by its unique composition. inclusion into omvs may impart a variety of benefits to the protein cargo, including: protection from pro ...201324370777
protein selection and export via outer membrane vesicles.outer membrane vesicles (omvs) are constitutively produced by all gram-negative bacteria. omvs form when buds from the outer membrane (om) of cells encapsulate periplasmic material and pinch off from the om to form spheroid particles approximately 10 to 300nm in diameter. omvs accomplish a diversity of functional roles yet the omv's utility is ultimately determined by its unique composition. inclusion into omvs may impart a variety of benefits to the protein cargo, including: protection from pro ...201324370777
rapid single-colony whole-genome sequencing of bacterial pathogens.as a result of the introduction of rapid benchtop sequencers, the time required to subculture a bacterial pathogen to extract sufficient dna for library preparation can now exceed the time to sequence said dna. we have eliminated this rate-limiting step by developing a protocol to generate dna libraries for whole-genome sequencing directly from single bacterial colonies grown on primary culture plates.201324370932
rapid single-colony whole-genome sequencing of bacterial pathogens.as a result of the introduction of rapid benchtop sequencers, the time required to subculture a bacterial pathogen to extract sufficient dna for library preparation can now exceed the time to sequence said dna. we have eliminated this rate-limiting step by developing a protocol to generate dna libraries for whole-genome sequencing directly from single bacterial colonies grown on primary culture plates.201324370932
masquerading microbial pathogens: capsular polysaccharides mimic host-tissue molecules.the increasing prevalence of antibiotic-resistant bacteria portends an impending postantibiotic age, characterized by diminishing efficacy of common antibiotics and routine application of multifaceted, complementary therapeutic approaches to treat bacterial infections, particularly multidrug-resistant organisms. the first line of defense for most bacterial pathogens consists of a physical and immunologic barrier known as the capsule, commonly composed of a viscous layer of carbohydrates that are ...201424372337
prevalence, concentration and genotypes of campylobacter jejuni in faeces from dairy herds managed in farm systems with or without housing.to determine the faecal excretion of campylobacter jejuni by dairy cows that used housing in combination with outdoor grazing.201424372778
identification of a broad family of lipid a late acyltransferases with non-canonical substrate specificity.most gram-negative organisms produce lipopolysaccharide (lps), a complex macromolecule anchored to the bacterial membrane by the lipid a moiety. lipid a is synthesized via the raetz pathway, a conserved nine-step enzymatic process first characterized in escherichia coli. the epsilonproteobacterium helicobacter pylori uses the raetz pathway to synthesize lipid a; however, only eight of nine enzymes in the pathway have been identified in this organism. here, we identify the missing acyltransferase ...201424372821
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
dietary nisin modulates the gastrointestinal microbial ecology and enhances growth performance of the broiler chickens.due to antimicrobial properties, nisin is one of the most commonly used and investigated bacteriocins for food preservation. surprisingly, nisin has had limited use in animal feed as well as there are only few reports on its influence on microbial ecology of the gastrointestinal tract (git). the present study therefore aimed at investigating effects of dietary nisin on broiler chicken git microbial ecology and performance in comparison to salinomycin, the widely used ionophore coccidiostat. in t ...201324376878
acute motor axonal neuropathy associated with anal carcinoma: paraneoplastic neurological syndrome or coincidence?assessment of the association of an acute motor axonal neuropathy with a squamous cell anal carcinoma.201124376957
the contribution of nutrient metal acquisition and metabolism to acinetobacter baumannii survival within the host.acinetobacter baumannii is a significant contributor to intensive care unit (icu) mortality causing numerous types of infection in this susceptible icu population, most notably ventilator-associated pneumonia. the substantial disease burden attributed to a. baumannii and the rapid acquisition of antibiotic resistance make this bacterium a serious health care threat. a. baumannii is equipped to tolerate the hostile host environment through modification of its metabolism and nutritional needs. amo ...201324377089
extra-intestinal and long term consequences of giardia duodenalis infections.giardiasis is the most common waterborne parasitic infection of the human intestine worldwide. the etiological agent, giardia duodenalis (syn. g. intestinalis, g. lamblia), is a flagellated, binucleated protozoan parasite which infects a wide array of mammalian hosts. human giardiasis is a true cosmopolitan pathogen, with highest prevalence in developing countries. giardiasis can present with a broad range of clinical manifestations from asymptomatic, to acute or chronic diarrheal disease associ ...201324379622
communication between bacteria and their hosts.it is clear that a dialogue is occurring between microbes and their hosts and that chemical signals are the language of this interkingdom communication. microbial endocrinology shows that, through their long coexistence with animals and plants, microorganisms have evolved sensors for detecting eukaryotic hormones, which the microbe uses to determine that they are within proximity of a suitable host and to optimally time the expression of genes needed for host colonisation. it has also been shown ...201324381789
comprehensive proteomic profiling of outer membrane vesicles from campylobacter jejuni.gram-negative bacteria constitutively release outer membrane vesicles (omvs) during cell growth that play significant roles in bacterial survival, virulence and pathogenesis. in this study, comprehensive proteomic analysis of omvs from a human gastrointestinal pathogen campylobacter jejuni nctc11168 was performed using high-resolution mass spectrometry. the omvs of c. jejuni nctc11168 were isolated from culture supernatants then characterized using electron microscopy and dynamic light scatterin ...201324382552
comprehensive proteomic profiling of outer membrane vesicles from campylobacter jejuni.gram-negative bacteria constitutively release outer membrane vesicles (omvs) during cell growth that play significant roles in bacterial survival, virulence and pathogenesis. in this study, comprehensive proteomic analysis of omvs from a human gastrointestinal pathogen campylobacter jejuni nctc11168 was performed using high-resolution mass spectrometry. the omvs of c. jejuni nctc11168 were isolated from culture supernatants then characterized using electron microscopy and dynamic light scatterin ...201324382552
biochemical, structural, and genetic characterization of tridecaptin a₁, an antagonist of campylobacter jejuni.bacillus circulans nrrl b-30644 (now paenibacillus terrae) was previously reported to produce srcam 1580, a bacteriocin active against the food pathogen campylobacter jejuni. we have been unable to isolate srcam 1580, and did not find any genetic determinants in the genome of this strain. we now report the reassignment of this activity to the lipopeptide tridecaptin a₁. structural characterization of tridecaptin a1 was achieved through nmr, ms/ms and gc-ms studies. the structure was confirmed th ...201424382692
iron homeostasis in the rhodobacter genus.metals are utilized for a variety of critical cellular functions and are essential for survival. however cells are faced with the conundrum of needing metals coupled with e fact that some metals, iron in particular are toxic if present in excess. maintaining metal homeostasis is therefore of critical importance to cells. in this review we have systematically analyzed sequenced genomes of three members of the rhodobacter genus, r. capsulatus sb1003, r. sphaeroides 2.4.1 and r. ferroxidans sw2 to ...201324382933
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
the bactericidal activity of carbon monoxide-releasing molecules against helicobacter pylori.helicobacter pylori is a pathogen that establishes long life infections responsible for chronic gastric ulcer diseases and a proved risk factor for gastric carcinoma. the therapeutic properties of carbon-monoxide releasing molecules (corms) led us to investigate their effect on h. pylori. we show that h. pylori 26695 is susceptible to two widely used corms, namely corm-2 and corm-3. also, several h. pylori clinical isolates were killed by corm-2, including those resistant to metronidazole. moreo ...201324386154
campylobacteriosis in urban versus rural areas: a case-case study integrated with molecular typing to validate risk factors and to attribute sources of infection.campylobacter infection is a leading cause of bacterial gastroenteritis worldwide, and most clinical cases appear as isolated, sporadic infections for which the source is rarely apparent. from july 2005 to december 2007 we conducted a prospective case-case study of sporadic, domestically-acquired campylobacter enteritis in rural versus urban areas and a prevalence study of campylobacter in animal and environmental sources in the eastern townships, quebec. isolates were typed using multilocus seq ...201324386265
the detection of foodborne bacteria on beef: the application of the electronic nose.this study aims to investigate the application of a fast electronic nose system (cyranose 320) for detecting foodborne bacteria. the system proved to be very efficient in detecting microbes in beef and sausage samples. in the first part of the study, the total viable counts (tvc) from fresh and frozen beef samples were determined using the standard microbiological method and by the application of the electronic nose. the second part applied the electronic nose to beef before and after contaminat ...201324386629
cas9-based tools for targeted genome editing and transcriptional control.development of tools for targeted genome editing and regulation of gene expression has significantly expanded our ability to elucidate the mechanisms of interesting biological phenomena and to engineer desirable biological systems. recent rapid progress in the study of a clustered, regularly interspaced short palindromic repeat (crispr)/crispr-associated (cas) protein system in bacteria has facilitated the development of newly facile and programmable platforms for genome editing and transcriptio ...201424389925
characterisation of a multi-ligand binding chemoreceptor ccml (tlp3) of campylobacter jejuni.campylobacter jejuni is the leading cause of human gastroenteritis worldwide with over 500 million cases annually. chemotaxis and motility have been identified as important virulence factors associated with c. jejuni colonisation. group a transducer-like proteins (tlps) are responsible for sensing the external environment for bacterial movement to or away from a chemical gradient or stimulus. in this study, we have demonstrated cj1564 (tlp3) to be a multi-ligand binding chemoreceptor and report ...201424391495
pentavalent single-domain antibodies reduce campylobacter jejuni motility and colonization in chickens.campylobacter jejuni is the leading cause of bacterial foodborne illness in the world, with symptoms ranging from acute diarrhea to severe neurological disorders. contaminated poultry meat is a major source of c. jejuni infection, and therefore, strategies to reduce this organism in poultry, are expected to reduce the incidence of campylobacter-associated diseases. we have investigated whether oral administration of c. jejuni-specific single-domain antibodies would reduce bacterial colonization ...201324391847
peptidoglycan ld-carboxypeptidase pgp2 influences campylobacter jejuni helical cell shape and pathogenic properties and provides the substrate for the dl-carboxypeptidase pgp1.despite the importance of campylobacter jejuni as a pathogen, little is known about the fundamental aspects of its peptidoglycan (pg) structure and factors modulating its helical morphology. a pg dl-carboxypeptidase pgp1 essential for maintenance of c. jejuni helical shape was recently identified. bioinformatic analysis revealed the cjj81176_0915 gene product as co-occurring with pgp1 in several organisms. deletion of cjj81176_0915 (renamed pgp2) resulted in straight morphology, representing the ...201424394413
emra1 membrane fusion protein of francisella tularensis lvs is required for resistance to oxidative stress, intramacrophage survival and virulence in mice.francisella tularensis is a category a biodefence agent that causes a fatal human disease known as tularaemia. the pathogenicity of f. tularensis depends on its ability to persist inside host immune cells primarily by resisting an attack from host-generated reactive oxygen and nitrogen species (ros/rns). based on the ability of f. tularensis to resist high ros/rns levels, we have hypothesized that additional unknown factors act in conjunction with known antioxidant defences to render ros resista ...201424397487
isolation of campylobacter from human stool samples.campylobacter is an undetected cause of diarrhoea especially under 5 years of age in most of the countries. isolation of this organism is difficult, expensive and cumbersome.201424399385
competition for zinc binding in the host-pathogen interaction.due to its favorable chemical properties, zinc is used as a structural or catalytic cofactor in a very large number of proteins. despite the apparent abundance of this metal in all cell types, the intracellular pool of loosely bound zinc ions available for biological exchanges is in the picomolar range and nearly all zinc is tightly bound to proteins. in addition, to limit bacterial growth, some zinc-sequestering proteins are produced by eukaryotic hosts in response to infections. therefore, to ...201324400228
real-time pcr threshold cycle cutoffs help to identify agents causing acute childhood diarrhea in zanzibar.molecular assays might improve the identification of causes of acute diarrheal disease but might lead to more frequent detection of asymptomatic infections. in the present study, real-time pcr targeting 14 pathogens was applied to rectal swabs from 330 children aged 2 to 59 months in zanzibar, including 165 patients with acute diarrhea and 165 asymptomatic control subjects. at least one pathogen was detected for 94% of the patients and 84% of the controls, with higher rates among patients for no ...201424403298
methyl-accepting chemotaxis proteins 3 and 4 are responsible for campylobacter jejuni chemotaxis and jejuna colonization in mice in response to sodium deoxycholate.methyl-accepting chemotaxis proteins (mcps), also termed transducer-like proteins (tlps), serve as sensors in bacterial chemotactic signalling, and detect attractants and promote bacterial movement towards suitable sites for colonization. campylobacter jejuni is a leading cause of human enteritis, but the mechanisms responsible for bacterial chemotaxis and early colonization in the jejunum of hosts are poorly understood. in the present study, we identified several types of bile and sodium deoxyc ...201424403598
double-locus sequence typing using pora and peb1a for epidemiological studies of campylobacter jejuni.campylobacter jejuni is the leading cause of foodborne bacterial gastroenteritis worldwide. bacterial typing schemes play an important role in epidemiological investigations to trace the source and route of transmission of the infectious agent by identifying outbreak and differentiating among sporadic infections. in this study, a double-locus sequence typing (dlst) scheme for c. jejuni based on concatenated partial sequences of pora and peb1a genes is proposed. the dlst scheme was validated usin ...201424404778
a single nucleotide in the promoter region modulates the expression of the β-lactamase oxa-61 in campylobacter jejuni.despite prevalent β-lactam resistance in campylobacter jejuni, an important zoonotic enteric pathogen, the molecular basis of β-lactamase-mediated β-lactam resistance is still largely unknown. in particular, some c. jejuni strains that carry β-lactamase gene blaoxa-61 (cj0299) are still susceptible to β-lactams with undetected β-lactamase activity, suggesting blaoxa-61 is subjected to regulation. the objective of this study was to determine the regulatory mechanism of β-lactamase in c. jejuni.201424408987
dendritic cells: a spot on sialic acid.glycans decorating cell surface and secreted proteins and lipids occupy the juncture where critical host-host and host-pathogen interactions occur. the role of glycan epitopes in cell-cell and cell-pathogen adhesive events is already well-established, and cell surface glycan structures change rapidly in response to stimulus and inflammatory cues. despite the wide acceptance that glycans are centrally implicated in immunity, exactly how glycans and their changes contribute to the overall immune r ...201324409183
nitazoxanide: nematicidal mode of action and drug combination studies.intestinal nematodes or roundworms (aka soil-transmitted helminths or sths) cause great disease. they infect upwards of two billion people, leading to high morbidity and a range of health problems, especially in infected children and pregnant women. development of resistance to the two main classes of drugs used to treat intestinal nematode infections of humans has been reported. to fight sth infections, we need new and more effective drugs and ways to improve the efficacy of the old drugs. one ...201424412397
role of enteric neurotransmission in host defense and protection of the gastrointestinal tract.host defense is a vital role played by the gastrointestinal tract. as host to an enormous and diverse microbiome, the gut has evolved an elaborate array of chemical and physicals barriers that allow the digestion and absorption of nutrients without compromising the mammalian host. the control of such barrier functions requires the integration of neural, humoral, paracrine and immune signaling, involving redundant and overlapping mechanisms to ensure, under most circumstances, the integrity of th ...201324412639
role of enteric neurotransmission in host defense and protection of the gastrointestinal tract.host defense is a vital role played by the gastrointestinal tract. as host to an enormous and diverse microbiome, the gut has evolved an elaborate array of chemical and physicals barriers that allow the digestion and absorption of nutrients without compromising the mammalian host. the control of such barrier functions requires the integration of neural, humoral, paracrine and immune signaling, involving redundant and overlapping mechanisms to ensure, under most circumstances, the integrity of th ...201324412639
campylobacter in small ruminants at slaughter: prevalence, pulsotypes and antibiotic resistance.the present study aimed to address the prevalence, pulsotypes, and antimicrobial susceptibility patterns of campylobacter species present in sheep and goat carcasses at slaughter. in total, 851 samples were collected (343 meat surfaces, 282 ileum contents, 226 liver surfaces) and 835 campylobacter isolates were detected in 274 out of 343 carcasses (116 kids, 110 lambs, 63 goats and 54 sheep). the contamination rates per carcass category were 78.4% for kids, 94.5% for lambs, 63.5% for goats, and ...201424412959
prevalence in bulk tank milk and epidemiology of campylobacter jejuni in dairy herds in northern italy.thermotolerant campylobacter spp. are frequently the cause of human gastroenteritis and have assumed more importance in italy following the increased consumption of raw milk. our objectives were to determine the prevalence and genotypes of campylobacter spp. in dairy herds and to investigate the possible sources of bulk milk contamination. bulk milk from dairy herds (n = 282) was cultured for campylobacter spp. and enterobacteriaceae. at three campylobacter jejuni-positive farms, bovine feces, p ...201424413598
cloning and expression of the erythromycin resistance determinant from campylobacter jejuni in escherichia coli.the erythromycin resistance gene (em(r)) from campylobacter jejuni aba94 plasmid dna was cloned into the puc18 vector and then expressed in escherichia coli. the location of the em(r) determinant on the chimeric plasmid was determined by restriction endonuclease mapping within a 0.8-kb ecori fragment. this fragment then hybridized to the 78-kb plasmid dna but not to the 3.3-or 12.6-kb plasmid dna of campylobacter jejuni aba94. em(r) in campylobacter jejuni is therefore probably plasmid-mediated.199524415023
molecular cloning and transposition of a kanamycin resistance determinant from campylobacter jejuni between replicons in escherichia coli.this paper reports a restriction map of a fragment of dna encoding kanamycin resistance cloned from plasmid dna of campylobacter jejuni aba94 in the recombinant plasmid prs9421-1. in transposition experiments, kanamycin-resistant r751::km9421 transconjugants appeared at frequencies of 10(-7) per donor cell. these transconjugants harboured a plasmid 4 kb larger than the parental 49 kb plasmid r751. restriction enzyme analysis and southern blot hybridization of these transconjugants showed that th ...199624415309
immunopathology of inflammatory bowel disease.inflammatory bowel disease (ibd) results from a complex series of interactions between susceptibility genes, the environment, and the immune system. the host microbiome, as well as viruses and fungi, play important roles in the development of ibd either by causing inflammation directly or indirectly through an altered immune system. new technologies have allowed researchers to be able to quantify the various components of the microbiome, which will allow for future developments in the etiology o ...201424415853
microbial mechanisms of tolerance to weak acid stress. 201324416030
a low complexity rapid molecular method for detection of clostridium difficile in stool.here we describe a method for the detection of clostridium difficile from stool using a novel low-complexity and rapid extraction process called heat elution (he). the he method is two-step and takes just 10 minutes, no specialist instruments are required and there is minimal hands-on time. a test method using he was developed in conjunction with loop-mediated isothermal amplification (lamp) combined with the real-time bioluminescent reporter system known as bart targeting the toxin b gene (tcdb ...201424416173
quorum sensing controls flagellar morphogenesis in burkholderia glumae.burkholderia glumae is a motile plant pathogenic bacterium that has multiple polar flagella and one luxr/luxi-type quorum sensing (qs) system, tofr/tofi. a qs-dependent transcriptional regulator, qsmr, activates flagellar master regulator flhdc genes. flhdc subsequently activates flagellar gene expression in b. glumae at 37°c. here, we confirm that the interplay between qs and temperature is critical for normal polar flagellar morphogenesis in b. glumae. in the wild-type bacterium, flagellar gen ...201424416296
incidence of marginal zone lymphoma in the united states, 2001-2009 with a focus on primary anatomic site.the aetiology of marginal zone lymphoma (mzl) is purported to differ by anatomic site. while this is supported by clinical series of single mzl sites, no population-based study has comprehensively assessed incidence patterns across sites. to gain insight into disease aetiology, we assessed mzl incidence by site using data from 18 u.s. surveillance, epidemiology and end results (seer) program population-based registries. we calculated age-adjusted incidence rates (irs) by sex, race, and calendar ...201424417667
clinical detection of human probiotics and human pathogenic bacteria by using a novel high-throughput platform based on next generation sequencing.the human body plays host to a vast array of bacteria, found in oral cavities, skin, gastrointestinal tract and the vagina. some bacteria are harmful while others are beneficial to the host. despite the availability of many methods to identify bacteria, most of them are only applicable to specific and cultivable bacteria and are also tedious. based on high throughput sequencing technology, this work derives 16s rrna sequences of bacteria and analyzes probiotics and pathogens species.201424418497
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
changes in cell morphology and polyamine composition during growth of campylobacter jejuni.resting cells of campylobacter jejuni were spherical whereas growing cells were mainly spiral. content of cadaverine increased with the decrease in spherical forms prior to growth commencing but production of spermidine increased in early log phase. cadaverine and spermidine are possibly involved in changes in cell morphology and growth, respectively.199424421028
ph and acidity in lactic-fermenting cereal gruels: effects on viability of enteropathogenic microorganisms.survival of bacillus cereus, campylobacter jejuni, enterotoxigenic escherichia coli, salmonella typhimurium and shigella flexneri during lactic acid fermentation of cereal gruels prepared from low-tannin (white) and high-tannin (red) sorghum varieties was studied. a previously fermented gruel (starter culture, sc) recycled daily or stored for 7, 14 or 28 days, germinated cereal flour (power flour, pf), or a combination of pf and sc (pf+sc) were used as starters. at 24 h, the ph of all gruels wit ...199424421191
antimicrobial resistance and antimicrobial use associated with laboratory-confirmed cases of campylobacter infection in two health units in ontario.a population-based study was conducted over a two-year period in the perth district (pd) and wellington-dufferin-guelph (wdg) health units in ontario to document antimicrobial resistance and antimicrobial use associated with clinical cases of laboratory-confirmed campylobacteriosis.201324421795
epidemiology of campylobacteriosis in germany - insights from 10 years of surveillance.campylobacteriosis caused by campylobacter spp. is the most common notifiable bacterial gastrointestinal disease in germany and a major problem in many other european countries as well. in contrast to other infectious diseases, e.g., salmonellosis, the annual number of notified campylobacteriosis cases has increased in germany and other european countries from 2001-2010.201424422983
inhibited growth of common enteropathogenic bacteria in lactic-fermented cereal gruels.a natural lactic fermentation of mixtures of water and whole flour of either maize or high-tannin sorghum was obtained either before or after cooking to a weaning gruel: the preparations had a final ph of about 3.8 (range 3.67 to 4.00) and a ratio of lactic acid to acetic acid of 9∶1 (w/w). the growth of added (about 10(7) c.f.u./g gruel) gram-negative intestinal pathogenic bacteria, enterotoxigenicescherichia coli, campylobacter jejuni, shigella flexneri andsalmonella typhimurium, was strongly ...199224425608
participation of the cytoskeletal and lysosomal compartments in campylobacter jejuni invasion of caco-2 cells, the cellular response by morphometric analysis and the presence of cytokine and chemokine transcripts.this study aimed to evaluate the participation of actin and tubulin in the process of internalisation, the interaction of bacterial phagosomes with lysosomes, the morphometric changes and the expression of inflammatory cytokines in caco-2 cells infected with campylobacter jejuni. both actin and tubulin participated in the process of internalisation. inside the cells, lysosomes fuse with phagosomes, which may lead to bacterial death because after 2 h, the bacteria were not detected by transmissio ...201224426102
participation of the cytoskeletal and lysosomal compartments in campylobacter jejuni invasion of caco-2 cells, the cellular response by morphometric analysis and the presence of cytokine and chemokine transcripts.this study aimed to evaluate the participation of actin and tubulin in the process of internalisation, the interaction of bacterial phagosomes with lysosomes, the morphometric changes and the expression of inflammatory cytokines in caco-2 cells infected with campylobacter jejuni. both actin and tubulin participated in the process of internalisation. inside the cells, lysosomes fuse with phagosomes, which may lead to bacterial death because after 2 h, the bacteria were not detected by transmissio ...201224426102
a method for molecular analysis of catalase gene diversity in seawater.catalase plays an important role in the metabolism of marine bacteria and has potential impact on the marine environment. four pcr primers were designed to amplify the catalase gene fragments in marine bacteria by applying metagenomic dna from yellow sea surface water as the template. of the four reproducible target pcr products, the longest one with 900 bp were chosen for catalase gene library construction by the t-vector and the white escherichia coli colonies in the library was screened throu ...201324426153
identification and characterization of an invasion antigen b gene from the oral pathogen campylobacter rectus.the oral bacterium, campylobacter rectus, is an etiological agent of periodontitis. the virulence genes of c. rectus are largely unknown. the aim of this study was to query c. rectus for the presence of an invasion antigen b (ciab) gene, which is needed for cell invasion by the related species campylobacter jejuni. pcr and pcr-walking identified a ciab from c. rectus. in silico analyses of c. rectus 314 ciab (cr-ciab) revealed an orf of 1,830 base pairs. the cr-ciab protein shared significant se ...201424426164
identification and characterization of an invasion antigen b gene from the oral pathogen campylobacter rectus.the oral bacterium, campylobacter rectus, is an etiological agent of periodontitis. the virulence genes of c. rectus are largely unknown. the aim of this study was to query c. rectus for the presence of an invasion antigen b (ciab) gene, which is needed for cell invasion by the related species campylobacter jejuni. pcr and pcr-walking identified a ciab from c. rectus. in silico analyses of c. rectus 314 ciab (cr-ciab) revealed an orf of 1,830 base pairs. the cr-ciab protein shared significant se ...201424426164
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
deep-sea hydrothermal vent epsilonproteobacteria encode a conserved and widespread nitrate reduction pathway (nap).despite the frequent isolation of nitrate-respiring epsilonproteobacteria from deep-sea hydrothermal vents, the genes coding for the nitrate reduction pathway in these organisms have not been investigated in depth. in this study we have shown that the gene cluster coding for the periplasmic nitrate reductase complex (nap) is highly conserved in chemolithoautotrophic, nitrate-reducing epsilonproteobacteria from deep-sea hydrothermal vents. furthermore, we have shown that the napa gene is expresse ...201424430487
enteric bacterial proteases in inflammatory bowel disease- pathophysiology and clinical implications.numerous reports have identified a dysbiosis in the intestinal microbiota in patients suffering from inflammatory bowel diseases (ibd), yet the mechanism(s) in which this complex microbial community initiates or perpetuates inflammation remains unclear. the purpose of this review is to present evidence for one such mechanism that implicates enteric microbial derived proteases in the pathogenesis of ibd. we highlight and discuss studies demonstrating that proteases and protease receptors are abun ...201324431894
milk-borne infections. an analysis of their potential effect on the milk industry.in developed countries such as the united states of america, foodborne illnesses account for 48 million infections per year. developing countries such as india face greater simultaneous challenges particularly since incorrect processing or storage of dairy products can represent a transmission hazard for a large number of pathogens and can be responsible for outbreaks of brucellosis, listeriosis, tuberculosis, etc. it is important to recognize the types of germs which can be transmitted through ...201224432270
sialic acids siglec interaction: a unique strategy to circumvent innate immune response by pathogens.sialic acids (sias) are nine-carbon keto sugars primarily present on the terminal residue of cell surface glycans. sialic acid binding immunoglobulins (ig)-like lectins (siglecs) are generally expressed on various immune cells. they selectively recognize different linkage-specific sialic acids and undertake a variety of cellular functions. many pathogens either synthesize or acquire sialic acids from the host. sialylated pathogens generally use siglecs to manipulate the host immune response. the ...201324434319
cytolethal distending toxin b as a cell-killing component of tumor-targeted anthrax toxin fusion proteins.cytolethal distending toxin (cdt) is produced by gram-negative bacteria of several species. it is composed of three subunits, cdta, cdtb, and cdtc, with cdtb being the catalytic subunit. we fused cdtb from haemophilus ducreyi to the n-terminal 255 amino acids of bacillus anthracis toxin lethal factor (lfn) to design a novel, potentially potent antitumor drug. as a result of this fusion, cdtb was transported into the cytosol of targeted cells via the efficient delivery mechanism of anthrax toxin. ...201424434511
campylobacter coli cultured from the stools of a patient with immunoproliferative small intestinal disease.campylobacter has been associated with immunoproliferative small intestinal disease (ipsid), on the basis of 16s rdna sequencing, in situ hybridization, and immunohistochemistry. here, for the first time, we have cultured campylobacter from the stools of a patient with ipsid. phenotypic analysis and whole genome sequencing identified campylobacter coli. pcr on a ipsid tissue biopsy sample was positive for campylobacter coli and negative for campylobacter jejuni. these findings further support a ...201424438451
on the fiftieth anniversary. postinfectious irritable bowel syndrome: mechanisms related to pathogens.gastrointestinal (gi) infections resulting from bacterial, viral, and parasitic pathogens predispose to postinfectious irritable bowel syndrome (pi-ibs) and other functional gi disorders. existing literature supports the role of enterochromaffin cell hyperplasia, serotonin synthesis and reuptake, impaired barrier function, altered immune activation, and potentially mast cell activation in the pathophysiology of pi-ibs.201424438587
helicobacter pylori rna polymerase α-subunit c-terminal domain shows features unique to ɛ-proteobacteria and binds nikr/dna complexes.bacterial rna polymerase is a large, multi-subunit enzyme responsible for transcription of genomic information. the c-terminal domain of the α subunit of rna polymerase (αctd) functions as a dna and protein recognition element localizing the polymerase on certain promoter sequences and is essential in all bacteria. although αctd is part of rna polymerase, it is thought to have once been a separate transcription factor, and its primary role is the recruitment of rna polymerase to various promoter ...201424442709
characterization and antigenicity of recombinant campylobacter jejuni flagellar capping protein flid.campylobacter jejuni, a flagellated, spiral-rod, gram-negative bacterium, is the leading pathogen of human acute bacterial gastroenteritis worldwide, and chickens are regarded as a major reservoir of this micro-organism. bacterial flagella, composed of more than 35 proteins, play important roles in colonization and adhesion to the mucosal surface of chicken caeca. in this study, the flagellar capping protein, flid, encoded by the flid gene, from the campylobacter jenuni d1-39 isolate was express ...201424445509
twin-arginine translocation system in helicobacter pylori: tatc, but not tatb, is essential for viability.the twin-arginine translocation (tat) system, needed to transport folded proteins across biological membranes, has not been characterized in the gastric pathogen helicobacter pylori. analysis of all h. pylori genome sequences available thus far reveals the presence of single copies of tata, tatb, and tatc needed for the synthesis of a fully functional tat system. based on the presence of the twin-arginine hallmark in their signal sequence, only four h. pylori proteins appear to be tat dependent: ...201424449753
co-occurrence of anaerobic bacteria in colorectal carcinomas.numerous cancers have been linked to microorganisms. given that colorectal cancer is a leading cause of cancer deaths and the colon is continuously exposed to a high diversity of microbes, the relationship between gut mucosal microbiome and colorectal cancer needs to be explored. metagenomic studies have shown an association between fusobacterium species and colorectal carcinoma. here, we have extended these studies with deeper sequencing of a much larger number (n = 130) of colorectal carcinoma ...201324450771
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