Publications

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validation of the ansr® for campylobacter method for detection of thermophilic campylobacter spp. in chicken carcass rinse and turkey sponge samples.a performance validation of the ansr® for campylobacter method was conducted in selected matrixes. this assay used selective nicking enzyme amplification technology to amplify target genes. samples were enriched for 20 to 24 h and then lysed. the assay was completed within 50 min using real-time detection in a combination incubator/fluorescence detector and software. when 50 distinct strains of campylobacter jejuni, c. lari, or c. coli were tested for inclusivity, all 50 strains produced positiv ...201627634328
the human milk oligosaccharide 2'-fucosyllactose quenches campylobacter jejuni-induced inflammation in human epithelial cells hep-2 and ht-29 and in mouse intestinal mucosa.campylobacter jejuni causes diarrhea worldwide; young children are most susceptible. binding of virulent c. jejuni to the intestinal mucosa is inhibited ex vivo by α1,2-fucosylated carbohydrate moieties, including human milk oligosaccharides (hmoss).201627629573
the influence of prior modes of growth, temperature, medium, and substrate surface on biofilm formation by antibiotic-resistant campylobacter jejuni.campylobacter jejuni is one of the most common causes of bacterial gastrointestinal food-borne infection worldwide. it has been suggested that biofilm formation may play a role in survival of these bacteria in the environment. in this study, the influence of prior modes of growth (planktonic or sessile), temperatures (37 and 42 °c), and nutrient conditions (nutrient broth and mueller-hinton broth) on biofilm formation by eight c. jejuni strains with different antibiotic resistance profiles was e ...201627623781
molecular epidemiology of campylobacter jejuni infection in israel-a nationwide study.the incidence of campylobacter infection in israel, particularly among children <2 years of age, has risen over the last decade and became one of the highest among industrialized countries. this study explored the molecular epidemiology of campylobacter jejuni in israel over a decade (2003-2012) using multilocus sequence typing (mlst) combined with demographic metadata. representative clinical isolates (438) from a large national repository together with selected veterinary isolates (74) were su ...201627615719
campylobacter jejuni: a rare agent in a child with peritoneal dialysis-related peritonitis.peritonitis is a serious problem in children receiving peritoneal dialysis. campylobacter jejuni is an unusual cause of peritonitis. a 10-year-old boy who had end stage renal failure due to atypical hemolytic uremic syndrome was admitted to our hospital with abdominal pain and fever. peritoneal dialysis fluid was cloudy and microscopic examination showed abundant leukocytes. intraperitoneal cefepime treatment was started. campylobacter jejuni was isolated from peritoneal dialysis fluid culture a ...201627606662
evidence of allosteric enzyme regulation via changes in conformational dynamics: a hydrogen/deuterium exchange investigation of dihydrodipicolinate synthase.dihydrodipicolinate synthase is a tetrameric enzyme of the diaminopimelate pathway in bacteria and plants. the protein catalyzes the condensation of pyruvate (pyr) and aspartate semialdehyde en route to the end product lysine (lys). dihydrodipicolinate synthase from campylobacter jejuni (cjdhdps) is allosterically inhibited by lys. cjdhdps is a promising antibiotic target, as highlighted by the recent development of a potent bis-lysine (bislys) inhibitor. the mechanism whereby lys and bislys all ...201627604304
decay rates of zoonotic pathogens and viral surrogates in soils amended with biosolids and manures and comparison of qpcr and culture derived rates.the purpose of this study was to establish inactivation decay constants of foodborne pathogens and coliphage in clay and sandy soils for future "downstream" analyses such as quantitative microbial risk analysis and to compare cultivation-dependent and -independent (e.g. qpcr) methods.201627585434
development of multiplex-mismatch amplification mutation-pcr assay for simultaneous detection of campylobacter jejuni and mutation in gyra gene related to fluoroquinolone resistance.campylobacter jejuni, a foodborne pathogen, is the major cause of enteritis in humans worldwide, however, its increasing resistance to fluoroquinolones reported recently is of a major concern. in the present study, multiplex-mismatch amplification mutation assay-polymerase chain reaction (mmama-pcr) was developed for the first time with the aim to quickly identify c. jejuni and to detect the single nucleotide mutation (c-257 to t) frequently observed in gyra gene, associated with the acquisition ...201627584716
prevalence and characteristics of salmonella and campylobacter in retail poultry meat in japan.this study was undertaken to determine the prevalence, antimicrobial susceptibility, and genetic relatedness of salmonella enterica subsp. enterica and campylobacter spp. in poultry meat, and to analyze the association of genetic types of these bacteria with their geographical distribution and antimicrobial resistance profiles. fifty-four and 71 of 100 samples were found to be contaminated with salmonella and campylobacter, respectively. nine salmonella serotypes were found, including s. enteric ...201627580577
antibodies from multiple sclerosis patients preferentially recognize hyperglucosylated adhesin of non-typeable haemophilus influenzae.in autoimmune diseases, there have been proposals that exogenous "molecular triggers", i.e., specific this should be 'non-self antigens' accompanying infectious agents, might disrupt control of the adaptive immune system resulting in serious pathologies. the etiology of the multiple sclerosis (ms) remains unclear. however, epidemiologic data suggest that exposure to infectious agents may be associated with increased ms risk and progression may be linked to exogenous, bacterially-derived, antigen ...201628008952
multiple cross displacement amplification combined with gold nanoparticle-based lateral flow biosensor for detection of vibrio parahaemolyticus.vibrio parahaemolyticus (v. parahaemolyticus) is a marine seafood-borne pathogen causing severe illnesses in humans and aquatic animals. in the present study, multiple cross displacement amplification was combined with a lateral flow biosensor (mcda-lfb) to detect the toxr gene of v. parahaemolyticus in dna extracts from pure cultures and spiked oyster homogenates. amplification was carried out at a constant temperature (62°c) for only 30 min, and amplification products were directly applied to ...201628066368
zika virus infection and guillain-barré syndrome in three patients from suriname.we present three patients from suriname who were diagnosed with guillain-barré syndrome (gbs) during the zika virus (zikv) outbreak in this country. one patient had a positive zikv urine real-time rt-pcr (qrt-pcr) result. the other two patients had a negative zikv urine qrt-pcr but a positive virus neutralization test and presence of igg antibodies against zikv in the serum. considering the evidence of a past zikv infection and absence of evidence for recent infections with the most common prece ...201628066317
high resolution crystal structure of the catalytic domain of mcr-1.the newly identified mobile colistin resistant gene (mcr-1) rapidly spread among different bacterial strains and confers colistin resistance to its host, which has become a global concern. based on sequence alignment, mcr-1 should be a phosphoethanolamine transferase, members of the yhjw/yjdb/yijp superfamily and catalyze the addition of phosphoethanolamine to lipid a, which needs to be validated experimentally. here we report the first high-resolution crystal structure of the c-terminal catalyt ...201628000749
antimicrobial properties of plant essential oils against human pathogens and their mode of action: an updated review.a wide range of medicinal and aromatic plants (maps) have been explored for their essential oils in the past few decades. essential oils are complex volatile compounds, synthesized naturally in different plant parts during the process of secondary metabolism. essential oils have great potential in the field of biomedicine as they effectively destroy several bacterial, fungal, and viral pathogens. the presence of different types of aldehydes, phenolics, terpenes, and other antimicrobial compounds ...201628090211
the cytolethal distending toxin produced by nontyphoidal salmonella serotypes javiana, montevideo, oranienburg, and mississippi induces dna damage in a manner similar to that of serotype typhi.select nontyphoidal salmonella enterica (nts) serotypes were recently found to encode the salmonella cytolethal distending toxin (s-cdt), an important virulence factor for serotype typhi, the causative agent of typhoid fever. using a pcr-based assay, we determined that among 21 nts serotypes causing the majority of food-borne salmonellosis cases in the united states, genes encoding s-cdt are conserved in isolates representing serotypes javiana, montevideo, and oranienburg but that among serotype ...201627999166
comparative genomics of h. pylori and non-pylori helicobacter species to identify new regions associated with its pathogenicity and adaptability.the genus helicobacter is a group of gram-negative, helical-shaped pathogens consisting of at least 36 bacterial species. helicobacter pylori (h. pylori), infecting more than 50% of the human population, is considered as the major cause of gastritis, peptic ulcer, and gastric cancer. however, the genetic underpinnings of h. pylori that are responsible for its large scale epidemic and gastrointestinal environment adaption within human beings remain unclear. core-pan genome analysis was performed ...201628078297
use of single molecule sequencing for comparative genomics of an environmental and a clinical isolate of clostridium difficile ribotype 078.how the pathogen clostridium difficile might survive, evolve and be transferred between reservoirs within the natural environment is poorly understood. some ribotypes are found both in clinical and environmental settings. whether these strains are distinct from each another and evolve in the specific environments is not established. the possession of a highly mobile genome has contributed to the genetic diversity and ongoing evolution of c. difficile. interpretations of genetic diversity have be ...201627964731
the capricious nature of bacterial pathogens: phasevarions and vaccine development.infectious diseases are a leading cause of morbidity and mortality worldwide, and vaccines are one of the most successful and cost-effective tools for disease prevention. one of the key considerations for rational vaccine development is the selection of appropriate antigens. antigens must induce a protective immune response, and this response should be directed to stably expressed antigens so the target microbe can always be recognized by the immune system. antigens with variable expression, due ...201628018352
influence of haem environment on the catalytic properties of the tetrathionate reductase tsda from campylobacter jejuni.bifunctional dihaem cytochrome c thiosulfate dehydrogenases/tetrathionate reductases (tsda) exhibit different catalytic properties depending on the source organism. in the human food-borne intestinal pathogen campylobacter jejuni, tsda functions as a tetrathionate reductase enabling respiration with tetrathionate as an alternative electron acceptor. in the present study, evidence is provided that cys(138) and met(255) serve as the sixth ligands of haem 1 and haem 2 respectively, in the oxidized ...201627789780
role of recombinant dna technology to improve life.in the past century, the recombinant dna technology was just an imagination that desirable characteristics can be improved in the living bodies by controlling the expressions of target genes. however, in recent era, this field has demonstrated unique impacts in bringing advancement in human life. by virtue of this technology, crucial proteins required for health problems and dietary purposes can be produced safely, affordably, and sufficiently. this technology has multidisciplinary applications ...201628053975
htra-mediated e-cadherin cleavage is limited to degp and degq homologs expressed by gram-negative pathogens.the serine proteases htra/degp secreted by the human gastrointestinal pathogens helicobacter pylori (h. pylori) and campylobacter jejuni (c. jejuni) cleave the mammalian cell adhesion protein e-cadherin to open intercellular adhesions. a wide range of bacteria also expresses the htra/degp homologs degq and/or degs, which significantly differ in structure and function.201627931258
complete genome sequence of bacteriophage ma12, which infects both campylobacter jejuni and salmonella enterica serovar enteritidis.here, we announce the complete genome sequence of salmonella enterica serovar enteritidis (s enteritidis) bacteriophage ma12, a 41-kb chromosome. the strain can infect both campylobacter jejuni (c. jejuni) and s enteritidis and can be used in phage therapy experiments with poultry and poultry meat.201627932636
characterization in helicobacter pylori of a nickel transporter essential for colonization that was acquired during evolution by gastric helicobacter species.metal acquisition is crucial for all cells and for the virulence of many bacterial pathogens. in particular, nickel is a virulence determinant for the human gastric pathogen helicobacter pylori as it is the cofactor of two enzymes essential for in vivo colonization, urease and a [nife] hydrogenase. to import nickel despite its scarcity in the human body, h. pylori requires efficient uptake mechanisms that are only partially defined. indeed, alternative ways of nickel entry were predicted to exis ...201627923069
genomic insights from whole genome sequencing of four clonal outbreak campylobacter jejuni assessed within the global c. jejuni population.whole genome sequencing (wgs) is useful for determining clusters of human cases, investigating outbreaks, and defining the population genetics of bacteria. it also provides information about other aspects of bacterial biology, including classical typing results, virulence, and adaptive strategies of the organism. cell culture invasion and protein expression patterns of four related multilocus sequence type 21 (st21) c. jejuni isolates from a significant canadian water-borne outbreak were previou ...201627912729
rapid, sensitive detection of bartonella quintana by loop-mediated isothermal amplification of the groel gene.trench fever, caused by bartonella quintana, is recognized as a re-emerging and neglected disease. rapid and sensitive detection approaches are urgently required to monitor and help control b. quintana infections. here, loop-mediated isothermal amplification (lamp), which amplifies target dna at a fixed temperature with high sensitivity, specificity and rapidity, was employed to detect b. quintana. thirty-six strains, including 10 b. quintana, 13 other bartonella spp., and 13 other common pathog ...201627916953
heat shock increases conjugation efficiency in clostridium difficile.clostridium difficile infection has increased in incidence and severity over the past decade, and poses a unique threat to human health. however, genetic manipulation of c. difficile remains in its infancy and the bacterium remains relatively poorly characterised. low-efficiency conjugation is currently the only available method for transfer of plasmid dna into c. difficile. this is practically limiting and has slowed progress in understanding this important pathogen. conjugation efficiency vari ...201627377776
dissecting the interplay between intestinal microbiota and host immunity in health and disease: lessons learned from germfree and gnotobiotic animal models.this review elaborates the development of germfree and gnotobiotic animal models and their application in the scientific field to unravel mechanisms underlying host-microbe interactions and distinct diseases. strictly germfree animals are raised in isolators and not colonized by any organism at all. the germfree state is continuously maintained by birth, raising, housing and breeding under strict sterile conditions. however, isolator raised germfree mice are exposed to a stressful environment an ...201627980855
draft genome sequences of campylobacter jejuni strains that cause abortion in livestock.campylobacter jejuni is an intestinal bacterium that can cause abortion in livestock. this publication announces the public release of 15 campylobacter jejuni genome sequences from isolates linked to abortion in livestock. these isolates are part of the 100k pathogen genome project and are from clinical cases at the university of california (uc) davis.201627908990
a dual filtration-based multiplex pcr method for simultaneous detection of viable escherichia coli o157:h7, listeria monocytogenes, and staphylococcus aureus on fresh-cut cantaloupe.fresh-cut cantaloupe is particularly susceptible to contamination with pathogenic bacteria, such as escherichia coli o157:h7, listeria monocytogenes, and staphylococcus aureus. therefore, development of rapid, yet accurate detection techniques is necessary to ensure food safety. in this study, a multiplex pcr system and propidium monoazide (pma) concentration were optimized to detect all viable pathogens in a single tube. a dual filtration system utilized a filtration membrane with different por ...201627906992
complementation of an aglb mutant of methanococcus maripaludis with heterologous oligosaccharyltransferases.the oligosaccharyltransferase is the signature enzyme for n-linked glycosylation in all domains of life. in archaea, this enzyme termed aglb, is responsible for transferring lipid carrier-linked glycans to select asparagine residues in a variety of target proteins including archaellins, s-layer proteins and pilins. this study investigated the ability of a variety of aglbs to compensate for the oligosaccharyltransferase activity in methanococcus maripaludis deleted for aglb, using archaellin flab ...201627907170
metagenome phylogenetic profiling of microbial community evolution in a tetrachloroethene-contaminated aquifer responding to enhanced reductive dechlorination protocols.chlorinated solvent contamination of potable water supplies is a serious problem worldwide. biostimulation protocols can successfully remediate chlorinated solvent contamination through enhanced reductive dechlorination pathways, however the process is poorly understood and sometimes stalls creating a more serious problem. whole metagenome techniques have the potential to reveal details of microbial community changes induced by biostimulation. here we compare the metagenome of a tetrachloroethen ...201627980706
concurrency of guillain-barre syndrome and acute transverse myelitis: a case report and review of literature.guillain-barré syndrome and acute transverse myelitis manifest as demyelinating diseases of the peripheral and central nervous system. concurrency of these two disorders is rarely documented in literature. a 4-year-old girl presenting with cough, fever, and an impaired walking ability was admitted to hospital. she had no previous complaints in her medical history. a physical examination revealed lack of muscle strength of the lower extremities and deep tendon reflexes. mri could not be carried o ...201628018472
the two-component system arlrs and alterations in metabolism enable staphylococcus aureus to resist calprotectin-induced manganese starvation.during infection the host imposes manganese and zinc starvation on invading pathogens. despite this, staphylococcus aureus and other successful pathogens remain capable of causing devastating disease. however, how these invaders adapt to host-imposed metal starvation and overcome nutritional immunity remains unknown. we report that arlrs, a global staphylococcal virulence regulator, enhances the ability of s. aureus to grow in the presence of the manganese-and zinc-binding innate immune effector ...201627902777
the 12 gastrointestinal pathogens spectrum of acute infectious diarrhea in a sentinel hospital, shenzhen, china.acute infectious gastroenteritis is one of the most common diseases among all ages, particularly in developing countries. the pathogen spectrum may differ among different regions and seasons. to investigate the etiology of acute diarrhea in shenzhen, a prospective study was conducted from august 2014 to september 2015. stools from 412 patients with diarrhea (286 of whom were adults) including the general epidemiological information of the patients were collected. the 19 pathogens were detected b ...201627965649
editorial: biofilms from a food microbiology perspective: structures, functions, and control strategies. 201627965657
environmental free-living amoebae isolated from soil in khon kaen, thailand, antagonize burkholderia pseudomallei.presence of burkholderia pseudomallei in soil and water is correlated with endemicity of melioidosis in southeast asia and northern australia. several biological and physico-chemical factors have been shown to influence persistence of b. pseudomallei in the environment of endemic areas. this study was the first to evaluate the interaction of b. pseudomallei with soil amoebae isolated from b. pseudomallei-positive soil site in khon kaen, thailand. four species of amoebae, paravahlkampfia ustiana, ...201627898739
dcite: measuring necessary cladistic information can help you reduce polytomy artefacts in trees.biologists regularly create phylogenetic trees to better understand the evolutionary origins of their species of interest, and often use genomes as their data source. however, as more and more incomplete genomes are published, in many cases it may not be possible to compute genome-based phylogenetic trees due to large gaps in the assembled sequences. in addition, comparison of complete genomes may not even be desirable due to the presence of horizontally acquired and homologous genes. a decision ...201627898695
the minor flagellin of campylobacter jejuni (flab) confers defensive properties against bacteriophage infection.a screen of bacteriophages infecting a panel of campylobacter jejuni pt14 gene knock-out mutants identified a role for the minor flagellin encoded by the flab gene, in the defense of the host against cp8unalikevirus bacteriophage cp_f1 infection. inactivation of the flab gene resulted in an increase in the susceptibility of pt14 cultures to infection by cp_f1 and an increase in bacteriophage yields. infection of wild type pt14 with cp_f1 produces turbid plaques in bacterial lawns, from which 78% ...201627965643
azithromycin vs. placebo for the clinical outcome in campylobacter concisus diarrhoea in adults: a randomized, double-blinded, placebo-controlled clinical trial.campylobacter concisus has been associated with prolonged mild diarrhoea, but investigations regarding the efficacy of antimicrobial treatment have not been reported previously. we initiated a phase 3, single-centre, randomized, double-blinded, placebo-controlled study comparing the efficacy of 500 mg once-daily dose of azithromycin with a 500 mg once-daily dose of placebo for three days, for the treatment of c. concisus diarrhoea in adult patients with a follow-up period of ten days. if symptom ...201627893820
exercise-induced stress behavior, gut-microbiota-brain axis and diet: a systematic review for athletes.fatigue, mood disturbances, under performance and gastrointestinal distress are common among athletes during training and competition. the psychosocial and physical demands during intense exercise can initiate a stress response activating the sympathetic-adrenomedullary and hypothalamus-pituitary-adrenal (hpa) axes, resulting in the release of stress and catabolic hormones, inflammatory cytokines and microbial molecules. the gut is home to trillions of microorganisms that have fundamental roles ...201627924137
altered intestinal microbiota-host mitochondria crosstalk in new onset crohn's disease.intestinal microbial dysbiosis is associated with crohn's disease (cd). however, the mechanisms leading to the chronic mucosal inflammation that characterizes this disease remain unclear. in this report, we use systems-level approaches to study the interactions between the gut microbiota and host in new-onset paediatric patients to evaluate causality and mechanisms of disease. we report an altered host proteome in cd patients indicative of impaired mitochondrial functions. in particular, mitocho ...201627876802
beyond antimicrobial resistance: evidence for a distinct role of the acrd efflux pump in salmonella biology.for over 20 years, bacterial multidrug resistance (mdr) efflux pumps have been studied because of their impact on resistance to antimicrobials. however, critical questions remain, including why produce efflux pumps under non-antimicrobial treatment conditions, and why have multiple pumps if their only purpose is antimicrobial efflux? salmonella spp. possess five efflux pump families, including the resistance-nodulation-division (rnd) efflux pumps. notably, the rnd efflux pump acrd has a unique s ...201627879336
catabolite and oxygen regulation of enterohemorrhagic escherichia coli virulence.the biogeography of the gut is diverse in its longitudinal axis, as well as within specific microenvironments. differential oxygenation and nutrient composition drive the membership of microbial communities in these habitats. moreover, enteric pathogens can orchestrate further modifications to gain a competitive advantage toward host colonization. these pathogens are versatile and adept when exploiting the human colon. they expertly navigate complex environmental cues and interkingdom signaling ...201627879335
age-related differences in the luminal and mucosa-associated gut microbiome of broiler chickens and shifts associated with campylobacter jejuni infection.despite the importance of gut microbiota for broiler performance and health little is known about the composition of this ecosystem, its development and response towards bacterial infections. therefore, the current study was conducted to address the composition and structure of the microbial community in broiler chickens in a longitudinal study from day 1 to day 28 of age in the gut content and on the mucosa. additionally, the consequences of a campylobacter (c.) jejuni infection on the microbia ...201627921008
one-step pcr detection of salmonella pullorum/gallinarum using a novel target: the flagellar biosynthesis gene flhb.salmonella enterica serovar pullorum/gallinarum is an important infectious pathogen that has caused widespread problems for chicken industry. traditional salmonella serotyping is an expensive and time-consuming process. in this study, we developed a rapid one-step polymerase chain reaction (pcr) method to identify s. pullorum/gallinarum. the pcr-based assay focuses on flhb, which shows a deficient region only in s. pullorum/gallinarum, compared with that of other serovars. the specificity and se ...201627920764
lipooligosaccharide locus classes and putative virulence genes among chicken and human campylobacter jejuni isolates.campylobacter cause morbidity and considerable economic loss due to hospitalization and post infectious sequelae such as reactive arthritis, guillain barré- and miller fischer syndromes. such sequelae have been linked to c. jejuni harboring sialic acid structures in their lipooligosaccharide (los) layer of the cell wall. poultry is an important source of human campylobacter infections but little is known about the prevalence of sialylated c. jejuni isolates and the extent of transmission of such ...201627871232
comparative genomics revealed multiple helicobacter pylori genes associated with biofilm formation in vitro.biofilm formation by helicobacter pylori may be one of the factors influencing eradication outcome. however, genetic differences between good and poor biofilm forming strains have not been studied.201627870886
campylobacters and their bacteriophages from chicken liver: the prospect for phage biocontrol.consumption of foods containing chicken liver has been associated with campylobacter enteritis. campylobacters can contaminate the surface of livers post-mortem but can also arise through systemic infection of colonising bacteria in live birds. the use of bacteriophage to reduce levels of campylobacter entering the food chain is a promising intervention approach but most phages have been isolated from chicken excreta. this study examined the incidence and contamination levels of campylobacter an ...201627565524
effect of antibiotic pre-treatment and pathogen challenge on the intestinal microbiota in mice.more than 50 years after the discovery of antibiotics, bacterial infections have decreased substantially; however, antibiotics also may have negative effects such as increasing susceptibility to pathogens. an intact microbiome is an important line of defense against pathogens. we sought to determine the effect of orally administered antibiotics both on susceptibility to pathogens and on impact to the microbiome. we studied campylobacter jejuni, one of the most common causes of human diarrhea, an ...201627891184
development of multiple cross displacement amplification label-based gold nanoparticles lateral flow biosensor for detection of shigella spp.shigella spp., the etiological agent of shigellosis or "bacillary dysentery," are responsible for considerable morbidity and mortality in excess of a million deaths globally per year. although pcr-based techniques (such as pcr-based dipstick biosensors) have been used for the molecular diagnosis of infectious disease, these assays were restricted due to the need for a sophisticated thermal cycling apparatus to denature target templates. to facilitate simple and rapid detection of target pathogen ...201627917160
patient-specific bacteroides genome variants in pouchitis.a 2-year longitudinal microbiome study of 22 patients who underwent colectomy with an ileal pouch anal anastomosis detected significant increases in distinct populations of bacteroides during 9 of 11 patient visits that coincided with inflammation (pouchitis). oligotyping and metagenomic short-read annotation identified bacteroides populations that occurred in early samples, bloomed during inflammation, and reappeared after antibiotic treatment. targeted cultivation of bacteroides isolates from ...201627935837
the pas domain-containing protein heur regulates heme uptake in campylobacter jejuni.campylobacter jejuni is a leading cause of bacterially derived gastroenteritis. a previous mutant screen demonstrated that the heme uptake system (chu) is required for full colonization of the chicken gastrointestinal tract. subsequent work identified a pas domain-containing regulator, termed heur, as being required for chicken colonization. here we confirm that both the heme uptake system and heur are required for full chicken gastrointestinal tract colonization, with the heur mutant being part ...201627935836
antibiotics in malaria therapy: which antibiotics except tetracyclines and macrolides may be used against malaria?malaria, a parasite vector-borne disease, is one of the most significant health threats in tropical regions, despite the availability of individual chemoprophylaxis. malaria chemoprophylaxis and chemotherapy remain a major area of research, and new drug molecules are constantly being developed before drug-resistant parasites strains emerge. the use of anti-malarial drugs is challenged by contra-indications, the level of resistance of plasmodium falciparum in endemic areas, clinical tolerance and ...201627846898
effects of seasonal meteorological variables on e. coli persistence in livestock faeces and implications for environmental and human health.agriculture contributes significant volumes of livestock faeces to land. understanding how faecal microbes respond to shifts in meteorological patterns of contrasting seasons is important in order to gauge how environmental (and human health) risks may alter under a changing climate. the aim of this study was to: (i) quantify the temporal pattern of e. coli growth within dairy faeces post defecation; and (ii) derive e. coli seasonal population change profiles associated with contrasting environm ...201627845409
25 years of proton pump inhibitors: a comprehensive review.proton pump inhibitors (ppis) were clinically introduced more than 25 years ago and have since proven to be invaluable, safe, and effective agents for the management of a variety of acid-related disorders. although all members in this class act in a similar fashion, inhibiting active parietal cell acid secretion, there are slight differences among ppis relating to their pharmacokinetic properties, metabolism, and food and drug administration (fda)-approved clinical indications. nevertheless, eac ...201627840364
25 years of proton pump inhibitors: a comprehensive review.proton pump inhibitors (ppis) were clinically introduced more than 25 years ago and have since proven to be invaluable, safe, and effective agents for the management of a variety of acid-related disorders. although all members in this class act in a similar fashion, inhibiting active parietal cell acid secretion, there are slight differences among ppis relating to their pharmacokinetic properties, metabolism, and food and drug administration (fda)-approved clinical indications. nevertheless, eac ...201627840364
engineering and dissecting the glycosylation pathway of a streptococcal serine-rich repeat adhesin.serine-rich repeat glycoproteins (srrps) are conserved in gram-positive bacteria. they are crucial for modulating biofilm formation and bacterial-host interactions. glycosylation of srrps plays a pivotal role in the process; thus understanding the glycosyltransferases involved is key to identifying new therapeutic drug targets. the glycosylation of fap1, an srrp of streptococcus parasanguinis, is mediated by a gene cluster consisting of six genes: gtf1, gtf2, gly, gtf3, dgt1, and galt2 mature fa ...201628039332
a novel, molybdenum-containing methionine sulfoxide reductase supports survival of haemophilus influenzae in an in vivo model of infection.haemophilus influenzae is a host adapted human mucosal pathogen involved in a variety of acute and chronic respiratory tract infections, including chronic obstructive pulmonary disease and asthma, all of which rely on its ability to efficiently establish continuing interactions with the host. here we report the characterization of a novel molybdenum enzyme, torz/mtsz that supports interactions of h. influenzae with host cells during growth in oxygen-limited environments. strains lacking torz/mts ...201627933034
life without dutpase.fine-tuned regulation of the cellular nucleotide pools is indispensable for faithful replication of deoxyribonucleic acid (dna). the genetic information is also safeguarded by dna damage recognition and repair processes. uracil is one of the most frequently occurring erroneous bases in dna; it can arise from cytosine deamination or thymine-replacing incorporation. two enzyme activities are primarily involved in keeping dna uracil-free: dutpase (dutp pyrophosphatase) activity that prevent thymine ...201627933035
a novel phase variant of the cholera pathogen shows stress-adaptive cryptic transcriptomic signatures.in a process known as phase variation, the marine bacterium and cholera pathogen vibrio cholerae alternately expresses smooth or rugose colonial phenotypes, the latter being associated with advanced biofilm architecture and greater resistance to ecological stress. to define phase variation at the transcriptomic level in pandemic v. cholerae o1 el tor strain n16961, we compared the rna-seq-derived transcriptomes among the smooth parent n16961, its rugose derivative (n16961r) and a smooth form obt ...201627842489
pneumococcal polysaccharide vaccination elicits igg anti-a/b blood group antibodies in healthy individuals and patients with type i diabetes mellitus.blood group antibodies are natural antibodies that develop early in life in response to cross-reactive environmental antigens in the absence of antigen encounter. even later in life structural similarities in saccharide composition between environmental antigens such as bacterial polysaccharides and blood group a/b antigens could lead to changes in serum levels, igm/igg isotype, and affinity maturation of blood group anti-a/b antibodies. we addressed the question whether immunization with pneumo ...201627895641
antibiotics: practice and opinions of cambodian commercial farmers, animal feed retailers and veterinarians.cambodia has reported multidrug resistant bacteria in poultry, similar to other countries in the region. we visited commercial food animal farms to explore opinions and antibiotic practices on the farms.201627857835
small regulatory rnas of rickettsia conorii.small regulatory rnas comprise critically important modulators of gene expression in bacteria, yet very little is known about their prevalence and functions in rickettsia species. r. conorii, the causative agent of mediterranean spotted fever, is a tick-borne pathogen that primarily infects microvascular endothelium in humans. we have determined the transcriptional landscape of r. conorii during infection of human microvascular endothelial cells (hmecs) by strand-specific rna sequencing to ident ...201627834404
differences in host breed and diet influence colonization by campylobacter jejuni and induction of local immune responses in chicken.chickens are regarded as the main reservoir for human campylobacteriosis. little is known about the interaction between campylobacter jejuni (c. jejuni) and chickens. this interaction may be influenced by the stage of maturation of the immune system, developing gut microbiota composition and other factors including breed and diet. our aim was to investigate the impact of breed, and diet on c. jejuni colonization and host immune responses in chickens. birds were inoculated with 10(4) colony formi ...201627843492
complete genome sequences of group iii campylobacter bacteriophages pc5 and pc14.here, we present the whole-genome sequences of bacteriophages pc5 and pc14 specific for campylobacter jejuni, a leading cause of gastroenteritis in developed countries. their genomes are syntenic to those of group iii campylobacter bacteriophages and share more than 90% identity at the nucleotide level with members of this group.201627834694
in vitro susceptibility of four antimicrobials against riemerella anatipestifer isolates: a comparison of minimum inhibitory concentrations and mutant prevention concentrations for ceftiofur, cefquinome, florfenicol, and tilmicosin.mutant prevention concentration (mpc) is an alternative pharmacodynamic parameter that has been used to measure antimicrobial activity and represents the propensities of antimicrobial agents to select resistant mutants. the concentration range between minimum inhibitory concentration (mic) and mpc is defined as mutant selection window (msw). the mpc and msw parameters represent the ability of antimicrobial agents to inhibit the bacterial mutants selected. this study was conducted to determine th ...201627829415
a structural and functional study on the 2-c-methyl-d-erythritol-4-phosphate cytidyltransferase (ispd) from bacillus subtilis.2-c-methyl-d-erythritol-4-phosphate cytidyltransferase (ispd) is an essential enzyme in the mevalonate-independent pathway of isoprenoid biosynthesis. this enzyme catalyzes 2-c-methyl-d-erythritol 4-phosphate (mep) and cytosine triphosphate (ctp) to 4-diphosphocytidyl-2-c-methyl-d-erythritol (cdpme) and inorganic pyrophosphate (ppi). bacillus subtilis was a kind of excellent isoprene producer. however, the studies on the key enzymes of mep pathway in b. subtilis were still absent. in this work, ...201627821871
aglh, a thermophilic udp-n-acetylglucosamine-1-phosphate:dolichyl phosphate glcnac-1-phosphotransferase initiating protein n-glycosylation pathway in sulfolobus acidocaldarius, is capable of complementing the eukaryal alg7.aglh, a predicted udp-glcnac-1-phosphate:dolichyl phosphate glcnac-1-phosphotransferase, is initiating the protein n-glycosylation pathway in the thermoacidophilic crenarchaeon sulfolobus acidocaldarius. aglh successfully replaced the endogenous glcnac-1-phosphotransferase activity of alg7 in a conditional lethal saccharomyces cerevisiae strain, in which the first step of the eukaryal protein n-glycosylation process was repressed. this study is one of the few examples of cross-domain complementa ...201627822701
aglh, a thermophilic udp-n-acetylglucosamine-1-phosphate:dolichyl phosphate glcnac-1-phosphotransferase initiating protein n-glycosylation pathway in sulfolobus acidocaldarius, is capable of complementing the eukaryal alg7.aglh, a predicted udp-glcnac-1-phosphate:dolichyl phosphate glcnac-1-phosphotransferase, is initiating the protein n-glycosylation pathway in the thermoacidophilic crenarchaeon sulfolobus acidocaldarius. aglh successfully replaced the endogenous glcnac-1-phosphotransferase activity of alg7 in a conditional lethal saccharomyces cerevisiae strain, in which the first step of the eukaryal protein n-glycosylation process was repressed. this study is one of the few examples of cross-domain complementa ...201627822701
rapid molecular approach for simultaneous detection of salmonella spp., shigella spp., and vibrio cholera.gastrointestinal tract infection is still one of the serious public health problems in many geographic areas and is endemic in most countries including iran. early detection of the gastrointestinal tract pathogens can be extremely important. the aim of the current study was to apply a shortened time-multiplex polymerase chain reaction (pcr) for rapid and simultaneous detection of salmonella spp., shigella spp., and vibrio cholera.201628053842
crispr-cas: biology, mechanisms and relevance.prokaryotes have evolved several defence mechanisms to protect themselves from viral predators. clustered regularly interspaced short palindromic repeats (crispr) and their associated proteins (cas) display a prokaryotic adaptive immune system that memorizes previous infections by integrating short sequences of invading genomes-termed spacers-into the crispr locus. the spacers interspaced with repeats are expressed as small guide crispr rnas (crrnas) that are employed by cas proteins to target i ...201627672148
complete structure of the bacterial flagellar hook reveals extensive set of stabilizing interactions.the bacterial flagellar hook is a tubular helical structure made by the polymerization of multiple copies of a protein, flge. here we report the structure of the hook from campylobacter jejuni by cryo-electron microscopy at a resolution of 3.5 å. on the basis of this structure, we show that the hook is stabilized by intricate inter-molecular interactions between flge molecules. extra domains in flge, found only in campylobacter and in related bacteria, bring more stability and robustness to the ...201627811912
zika virus: a review from the virus basics to proposed management strategies.this review aims to summarize the body of knowledge available on zika virus to date. a comprehensive review of the scientific literature on zika virus was performed with the aim to stress relevant aspects for healthcare professionals in the non-endemic areas. for several years, the zika virus infection was considered an extremely rare exotic disease with poor clinical relevance. however, zika virus has recently gained the attention of the scientific community and public opinion since the virus s ...201627872736
multiplex-touchdown pcr to simultaneously detect cryptosporidium parvum, giardia lamblia, and cyclospora cayetanensis, the major causes of traveler's diarrhea.this study aimed to develop a multiplex-touchdown pcr method to simultaneously detect 3 species of protozoan parasites, i.e., cryptosporidium parvum, giardia lamblia, and cyclospora cayetanensis, the major causes of traveler's diarrhea and are resistant to standard antimicrobial treatments. the target genes included the cryptosporidium oocyst wall protein for c. parvum, glutamate dehydrogenase for g. lamblia, and 18s ribosomal rna (18s rrna) for c. cayetanensis. the sizes of the amplified fragme ...201627853120
application of probiotics for the production of safe and high-quality poultry meat.poultry industry has always been a dynamic and integral part of national economies in many countries. economic losses incur especially in large-scale rearing facilities, often attributed to the deterioration of environmental conditions, poultry exposure to stressors and development of diseases. while antibiotics have been commonly used for prophylactic purposes and as growth stimulants, extensive documentation of antimicrobial resistance among pathogenic bacteria due to indiscriminate utilizatio ...201627857531
genetic characteristics and multiple-pcr development for capsular identification of specific serotypes of campylobacter jejuni.the polysaccharide capsule (cps) of campylobacter jejuni is a virulence factor linked to cell surface carbohydrate diversity which mainly determines the serotypes. thirty-four cps gene cluster structures have been published and some of them can be distinguished by multiple-pcr. penner serotypes hs1/44c, hs2, hs4c, hs19, hs23/36c and hs41 are markers for guillain-barré syndrome (gbs). the capsules may contribute to gbs susceptibility. analysis of 18 cps loci revealed high gene content diversity a ...201627788180
fucosyllactose and l-fucose utilization of infant bifidobacterium longum and bifidobacterium kashiwanohense.human milk oligosaccharides (hmos) are one of the major glycan source of the infant gut microbiota. the two species that predominate the infant bifidobacteria community, bifidobacterium longum subsp. infantis and bifidobacterium bifidum, possess an arsenal of enzymes including α-fucosidases, sialidases, and β-galactosidases to metabolise hmos. recently bifidobacteria were obtained from the stool of six month old kenyan infants including species such as bifidobacterium kashiwanohense, and bifidob ...201627782805
γ-glutamyltranspeptidase is an endogenous activator of toll-like receptor 4-mediated osteoclastogenesis.chronic inflammation-associated bone destruction, which is observed in rheumatoid arthritis (ra) and periodontitis, is mediated by excessive osteoclastogenesis. we showed previously that γ-glutamyltranspeptidase (ggt), an enzyme involved in glutathione metabolism, acts as an endogenous activator of such pathological osteoclastogenesis, independent of its enzymatic activity. ggt accumulation is clinically observed in the joints of ra patients, and, in animals, the administration of recombinant gg ...201627775020
cell resistance to the cytolethal distending toxin involves an association of dna repair mechanisms.the cytolethal distending toxin (cdt), produced by many bacteria, has been associated with various diseases including cancer. cdt induces dna double-strand breaks (dsbs), leading to cell death or mutagenesis if misrepaired. at low doses of cdt, other dna lesions precede replication-dependent dsb formation, implying that non-dsb repair mechanisms may contribute to cdt cell resistance. to address this question, we developed a proliferation assay using human cell lines specifically depleted in each ...201627775089
a comparative study of chip-seq sequencing library preparation methods.chip-seq is the primary technique used to investigate genome-wide protein-dna interactions. as part of this procedure, immunoprecipitated dna must undergo "library preparation" to enable subsequent high-throughput sequencing. to facilitate the analysis of biopsy samples and rare cell populations, there has been a recent proliferation of methods allowing sequencing library preparation from low-input dna amounts. however, little information exists on the relative merits, performance, comparability ...201627769162
travel-related illness at a tertiary care hospital in osaka, japan.we analyzed the travel-related health problems in persons returning to japan from overseas. data were extracted retrospectively for all patients visiting the infectious diseases department of osaka city general hospital, osaka, japan, between july 2012 and september 2013. there were 209 sick returning travelers during the period of the study. the median age of the subjects was 34.3 years, and the subjects consisted of 133 tourists (63.6%), 39 business travelers (18.7%), 17 expatriates (8.1%), 14 ...201627799812
evaluation and selection of bacillus species based on enzyme production, antimicrobial activity, and biofilm synthesis as direct-fed microbial candidates for poultry.social concern about misuse of antibiotics as growth promoters (agp) and generation of multidrug-resistant bacteria have restricted the dietary inclusion of antibiotics in livestock feed in several countries. direct-fed microbials (dfm) are one of the multiple alternatives commonly evaluated as substitutes of agp. sporeformer bacteria from the genus bacillus have been extensively investigated because of their extraordinary properties to form highly resistant endospores, produce antimicrobial com ...201627812526
variations of phosphorous accessibility causing changes in microbiome functions in the gastrointestinal tract of chickens.the chicken gastrointestinal tract (git) harbours a complex microbial community, involved in several physiological processes such as host immunomodulation and feed digestion. for the first time, the present study analysed dietary effects on the protein inventory of the microbiome in crop and ceca of broilers. we performed quantitative label-free metaproteomics by using 1-d-gel electrophoresis coupled with lc-ms/ms to identify the structural and functional changes triggered by diets supplied with ...201627760159
chicken immune response after in ovo immunization with chimeric tlr5 activating flagellin of campylobacter jejuni.campylobacter jejuni is the main cause of bacterial food-borne diseases in developed countries. chickens are the most important source of human infection. vaccination of poultry is an attractive strategy to reduce the number of c. jejuni in the intestinal tract of chickens. we investigated the immunogenicity and protective efficacy of a recombinant c. jejuni flagellin-based subunit vaccine with intrinsic adjuvant activity. toll-like receptor activation assays demonstrated the purity and tlr5 sti ...201627760175
structural insights into bacterial flagellar hooks similarities and specificities.across bacteria, the protein that makes the flagellar hook, flge, has a high variability in amino acid residue composition and sequence length. we hereby present the structure of two fragments of flge protein from campylobacter jejuni and from caulobacter crescentus, which were obtained by x-ray crystallography, and a high-resolution model of the hook from caulobacter. by comparing these new structures of flge proteins, we show that bacterial hook can be divided in two distinct parts. the first ...201627759043
identification of residues in the lipopolysaccharide abc transporter that coordinate atpase activity with extractor function.the surface of most gram-negative bacteria is covered with lipopolysaccharide (lps), creating a permeability barrier against toxic molecules, including many antimicrobials. to assemble lps on their surface, gram-negative bacteria must extract newly synthesized lps from the inner membrane, transport it across the aqueous periplasm, and translocate it across the outer membrane. the lpta to -g proteins assemble into a transenvelope complex that transports lps from the inner membrane to the cell sur ...201627795402
classification of a hypervirulent aeromonas hydrophila pathotype responsible for epidemic outbreaks in warm-water fishes.lineages of hypervirulent aeromonas hydrophila (vah) are the cause of persistent outbreaks of motile aeromonas septicemia in warm-water fishes worldwide. over the last decade, this virulent lineage of a. hydrophila has resulted in annual losses of millions of tons of farmed carp and catfish in the people's republic of china and the united states (us). multiple lines of evidence indicate us catfish and asian carp isolates of a. hydrophila affiliated with sequence type 251 (st251) share a recent c ...201627803692
epidemiological and clinical profile of adult patients with blastocystis sp. infection in barcelona, spain.blastocystis spp. are among the most frequently observed intestinal parasites in humans. despite the discovery of blastocystis approximately 100 years ago, limited information is available regarding its pathogenesis, genetic diversity, and available treatment options. the aim of this study was to describe the epidemiological and clinical characteristics of patients with blastocystis sp. infections diagnosed at vall d'hebron university hospital (barcelona, spain).201627741951
virulence and genomic feature of multidrug resistant campylobacter jejuni isolated from broiler chicken.the aim of this study was to reveal the molecular mechanism involved in multidrug resistance and virulence of campylobacter jejuni isolated from broiler chickens. the virulence of six multidrug resistant c. jejuni was determined by in vitro and in vivo methods. the de novo whole genome sequencing technology and molecular biology methods were used to analyze the genomic features associated with the multidrug resistance and virulence of a selected isolate (c. jejuni 1655). the comparative genomic ...201627790202
bacterial intra-species gene loss occurs in a largely clocklike manner mostly within a pool of less conserved and constrained genes.gene loss is a major contributor to the evolution of bacterial gene content. gene loss may occur as a result of shifts in environment leading to changes in the intensity and/or directionality of selection applied for the maintenance of specific genes. gene loss may also occur in a more neutral manner, when gene functions are lost that were not subject to strong selection to be maintained, irrespective of changes to environment. here, we used a pangenome-based approach to investigate patterns of ...201627734920
spyb, a small heme-binding protein, affects the composition of the cell wall in streptococcus pyogenes.streptococcus pyogenes (group a streptococcus or gas) is a hemolytic human pathogen associated with a wide variety of infections ranging from minor skin and throat infections to life-threatening invasive diseases. the cell wall of gas consists of peptidoglycan sacculus decorated with a carbohydrate comprising a polyrhamnose backbone with immunodominant n-acetylglucosamine side-chains. all gas genomes contain the spyba operon, which encodes a 35-amino-acid membrane protein spyb, and a membrane-bo ...201627790410
comparison of proteomics profiles of campylobacter jejuni strain bf under microaerobic and aerobic conditions.campylobacter jejuni accounts for one of the leading causes of foodborne bacterial enteritis in humans. despite being considered an obligate microaerobic microorganism, c. jejuni is regularly exposed to oxidative stress. however, its adaptive strategies to survive the atmospheric oxygen level during transmission to humans remain unclear. recently, the clinical c. jejuni strain bf was singled out for its unexpected ability to grow under ambient atmosphere. here, we aimed to understand better the ...201627790195
spatial and temporal shifts in bacterial biogeography and gland occupation during the development of a chronic infection.gland colonization may be one crucial route for bacteria to maintain chronic gastrointestinal infection. we developed a quantitative gland isolation method to allow robust bacterial population analysis and applied it to the gastric pathobiont helicobacter pylori after infections in the murine model system, h. pylori populations multiply both inside and outside glands in a manner that requires the bacteria to be motile and chemotactic. h. pylori is able to achieve gland densities averaging 25 to ...201627729513
the type b flagellin of hypervirulent clostridium difficile is modified with novel sulfonated peptidylamido-glycans.glycosylation of flagellins is a well recognized property of many bacterial species. in this study, we describe the structural characterization of novel flagellar glycans from a number of hypervirulent strains of c. difficile we used mass spectrometry (nano-lc-ms and ms/ms analysis) to identify a number of putative glycopeptides that carried a variety of glycoform substitutions, each of which was linked through an initial n-acetylhexosamine residue to ser or thr. detailed analysis of a lldgsstei ...201627758867
the gut microbiome as therapeutic target in central nervous system diseases: implications for stroke.research on commensal microbiota and its contribution to health and disease is a new and very dynamically developing field of biology and medicine. recent experimental and clinical investigations underscore the importance of gut microbiota in the pathogenesis and course of stroke. importantly, microbiota may influence the outcome of cerebral ischemia by modulating central nervous system antigen-specific immune responses. in this review we summarize studies linking gut microbiota with physiologic ...201627714645
complete genomic sequence of campylobacter jejuni subsp. jejuni hs:19 strain rm1285 isolated from packaged chicken.poultry products serve as the main source of campylobacter jejuni subsp. jejuni infections in humans. c. jejuni subsp. jejuni infections are a leading cause of foodborne gastroenteritis and are a prevalent antecedent to guillain-barré syndrome. this study describes the genome of c. jejuni subsp. jejuni hs:19 strain rm1285, isolated from packaged chicken in california.201627795263
identification of ompa-like protein of tannerella forsythia as an o-linked glycoprotein and its binding capability to lectins.bacterial glycoproteins are associated with physiological and pathogenic functions of bacteria. it remains unclear whether bacterial glycoproteins can bind to specific classes of lectins expressed on host cells. tannerella forsythia is a gram-negative oral anaerobe that contributes to the development of periodontitis. in this study, we aimed to find lectin-binding glycoproteins in t. forsythia. we performed affinity chromatography of wheat germ agglutinin, which binds to n-acetylglucosamine (glc ...201627711121
the bacterial mfd protein prevents dna damage induced by the host nitrogen immune response in a ner-independent but recbc-dependent pathway.production of reactive nitrogen species is an important component of the host immune defence against bacteria. here, we show that the bacterial protein mfd (mutation frequency decline), a highly conserved and ubiquitous bacterial protein involved in dna repair, confers bacterial resistance to the eukaryotic nitrogen response produced by macrophage cells and during mice infection. in addition, we show that recbc is also necessary to survive this stress. the inactivation of recbc and mfd genes is ...201627711223
gut microbiota-brain axis.to systematically review the updated information about the gut microbiota-brain axis.201627647198
role of glycosyltransferases modifying type b flagellin of emerging hypervirulent clostridium difficile lineages and their impact on motility and biofilm formation.clostridium difficile is the principal cause of nosocomial infectious diarrhea worldwide. the pathogen modifies its flagellin with either a type a or type b o-linked glycosylation system, which has a contributory role in pathogenesis. we study the functional role of glycosyltransferases modifying type b flagellin in the 023 and 027 hypervirulent c. difficile lineages by mutagenesis of five putative glycosyltransferases and biosynthetic genes. we reveal their roles in the biosynthesis of the flag ...201627703012
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