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motif depletion in bacteriophages infecting hosts with crispr systems.crispr is a microbial immune system likely to be involved in host-parasite coevolution. it functions using target sequences encoded by the bacterial genome, which interfere with invading nucleic acids using a homology-dependent system. the system also requires protospacer associated motifs (pams), short motifs close to the target sequence that are required for interference in crispr types i and ii. here, we investigate whether pams are depleted in phage genomes due to selection pressure to escap ...201425103210
polyphosphate-mediated modulation of campylobacter jejuni biofilm growth and stability.biofilms increase c. jejuni's resilience to detergents, antibiotics, and environmental stressors. in these investigations, we studied the modulation of biofilm in response to phosphate related stressors. we found that the deletion of ppk1, phox, and ppk2 (polyphosphate associated [poly p] genes) in c. jejuni modulated different stages of biofilm formation such as attached microcolonies, air-liquid biofilms, and biofilm shedding. additionally, inorganic phosphate also modulated attached microcolo ...201425127528
protein localization analysis of essential genes in prokaryotes.essential genes, those critical for the survival of an organism under certain conditions, play a significant role in pharmaceutics and synthetic biology. knowledge of protein localization is invaluable for understanding their function as well as the interaction of different proteins. however, systematical examination of essential genes from the aspect of the localizations of proteins they encode has not been explored before. here, a comprehensive protein localization analysis of essential genes ...201425105358
gastroenteritis due to typhoidal salmonella: a decade of observation at an urban and a rural diarrheal disease hospital in bangladesh.the study aimed to compare the socio-demographic, host and clinical characteristics, seasonality and antimicrobial susceptibility of typhoidal salmonella (salmonella enterica serovar typhi and paratyphi) (ts) with diarrhea between urban and rural bangladesh.201425098316
the rnase r from campylobacter jejuni has unique features and is involved in the first steps of infection.bacterial pathogens must adapt/respond rapidly to changing environmental conditions. ribonucleases (rnases) can be crucial factors contributing to the fast adaptation of rna levels to different environmental demands. it has been demonstrated that the exoribonuclease polynucleotide phosphorylase (pnpase) facilitates survival of campylobacter jejuni in low temperatures and favors swimming, chick colonization, and cell adhesion/invasion. however, little is known about the mechanism of action of oth ...201425100732
nild crispr rna contributes to xenorhabdus nematophila colonization of symbiotic host nematodes.the bacterium xenorhabdus nematophila is a mutualist of entomopathogenic steinernema carpocapsae nematodes and facilitates infection of insect hosts. x. nematophila colonizes the intestine of s. carpocapsae which carries it between insects. in the x. nematophila colonization-defective mutant nild6::tn5, the transposon is inserted in a region lacking obvious coding potential. we demonstrate that the transposon disrupts expression of a single crispr rna, nild rna. a variant nild rna also is expres ...201425041533
fourier transform infra-red spectroscopy and flow cytometric assessment of the antibacterial mechanism of action of aqueous extract of garlic (allium sativum) against selected probiotic bifidobacterium strains.it is generally reported that garlic (allium sativum) harms pathogenic but not beneficial bacteria. although numerous studies supporting the alleged garlic effects on pathogens are available, there are limited studies to prove this claim for beneficial bacteria. we have recently shown that garlic exhibits antibacterial activity against probiotic bifidobacteria. the aim of the current study was to elucidate the mechanism of action of garlic clove extract (gce) on bifidobacterium bifidum lmg 11041 ...201425099661
phenotypes of campylobacter jejuni luxs mutants are depending on strain background, kind of mutation and experimental conditions.since the discovery that campylobacter (c.) jejuni produces autoinducer 2 (ai-2), various studies have been conducted to explore the function and role of ai-2 in c. jejuni. however, the interpretation of these analyses has been complicated by differences in strain backgrounds, kind of mutation and culture conditions used. furthermore, all research on ai-2 dependent phenotypes has been conducted with ai-2 synthase (luxs) mutants. this mutation also leads to a disruption of the activated-methyl-cy ...201425093839
nanotechnology in agriculture: prospects and constraints.attempts to apply nanotechnology in agriculture began with the growing realization that conventional farming technologies would neither be able to increase productivity any further nor restore ecosystems damaged by existing technologies back to their pristine state; in particular because the long-term effects of farming with "miracle seeds", in conjunction with irrigation, fertilizers, and pesticides, have been questioned both at the scientific and policy levels, and must be gradually phased out ...201425187699
induction of endoplasmic reticulum stress and unfolded protein response constitutes a pathogenic strategy of group a streptococcus.the connection between bacterial pathogens and unfolded protein response (upr) is poorly explored. in this review we highlight the evidence showing that group a streptococcus (gas) induces endoplasmic reticulum (er) stress and upr through which it captures the amino acid asparagine (asn) from the host. gas acts extracellularly and during adherence to host cells it delivers the hemolysin toxins; streptolysin o (slo) and streptolysin s (sls). by poorly understood pathways, these toxins trigger upr ...201425136516
antibiotics in agriculture and the risk to human health: how worried should we be?the use of antibiotics in agriculture is routinely described as a major contributor to the clinical problem of resistant disease in human medicine. while a link is plausible, there are no data conclusively showing the magnitude of the threat emerging from agriculture. here, we define the potential mechanisms by which agricultural antibiotic use could lead to human disease and use case studies to critically assess the potential risk from each. the three mechanisms considered are as follows 1: dir ...201425861382
antibiotics in agriculture and the risk to human health: how worried should we be?the use of antibiotics in agriculture is routinely described as a major contributor to the clinical problem of resistant disease in human medicine. while a link is plausible, there are no data conclusively showing the magnitude of the threat emerging from agriculture. here, we define the potential mechanisms by which agricultural antibiotic use could lead to human disease and use case studies to critically assess the potential risk from each. the three mechanisms considered are as follows 1: dir ...201425861382
collapsing glomerulopathy after plasmodium falciparum infection. 201425878787
multilocus sequence typing confirms wild birds as the source of a campylobacter outbreak associated with the consumption of raw peas.from august to september 2008, the centers for disease control and prevention (cdc) assisted the alaska division of public health with an outbreak investigation of campylobacteriosis occurring among the residents of southcentral alaska. during the investigation, pulsed-field gel electrophoresis (pfge) of campylobacter jejuni isolates from human, raw pea, and wild bird fecal samples confirmed the epidemiologic link between illness and the consumption of raw peas contaminated by sandhill cranes fo ...201424837383
genomic variation between campylobacter jejuni isolates associated with milk-borne-disease outbreaks.bacterial genome sequencing has led to the development of new approaches for the analysis of food-borne epidemics and the exploration of the relatedness of outbreak-associated isolates and their separation from nonassociated isolates. using illumina technology, we sequenced a total of six isolates (two from patients, two from raw bulk milk, and two from dairy cattle) associated with a milk-borne campylobacter jejuni outbreak in a farming family and compared their genomes. these isolates had iden ...201424850348
preclinical studies of amixicile, a systemic therapeutic developed for treatment of clostridium difficile infections that also shows efficacy against helicobacter pylori.amixicile shows efficacy in the treatment of clostridium difficile infections (cdi) in a mouse model, with no recurrence of cdi. since amixicile selectively inhibits the action of a b vitamin (thiamine pyrophosphate) cofactor of pyruvate:ferredoxin oxidoreductase (pfor), it may both escape mutation-based drug resistance and spare beneficial probiotic gut bacteria that do not express this enzyme. amixicile is a water-soluble derivative of nitazoxanide (ntz), an antiparasitic therapeutic that also ...201424890599
requirement of the flagellar protein export apparatus component flio for optimal expression of flagellar genes in helicobacter pylori.flagellar biogenesis in helicobacter pylori involves the coordinated expression of flagellar genes with assembly of the flagellum. the h. pylori flagellar genes are organized into three regulons based on the sigma factor needed for their transcription (rpod [σ(80)], rpon [σ(54)], or flia [σ(28)]). transcription of rpon-dependent genes is activated by a two-component system consisting of the sensor kinase flgs and the response regulator flgr. while the cellular cues sensed by the flgs/flgr two-co ...201424837287
more severe manifestations and poorer short-term prognosis of ganglioside-associated guillain-barré syndrome in northeast china.ganglioside as a neurotrophic drug has been hitherto widely used in china, although guillain-barré syndrome (gbs) following intravenous ganglioside treatment was reported in europe several decades ago. we identified 7 patients who developed gbs after intravenous use of gangliosides (ganglioside+ group) and compared their clinical data with those of 77 non-ganglioside-associated gbs patients (ganglioside- group) in 2013, aiming at gaining the distinct features of ganglioside-associated gbs. altho ...201425084153
identification of a salmonella ancillary copper detoxification mechanism by a comparative analysis of the genome-wide transcriptional response to copper and zinc excess.copper and zinc are essential metal ions, but toxic in excess. bacteria have evolved different strategies to control their intracellular concentrations, ensuring proper supply while avoiding toxicity, including the induction of metal-specific as well as non-specific mechanisms. we compared the transcriptional profiles of salmonella typhimurium after exposure to either copper or zinc ions in both rich and minimal media. besides metal-specific regulatory networks many global stress-response pathwa ...201424858080
pharmacokinetics of oral chlortetracycline in nonpregnant adult ewes.the objectives of this study were to determine plasma concentrations and pharmacokinetic parameters of feed-grade chlortetracycline (ctc) in sheep after oral administration of 80 or 500 mg/head daily, divided into two equal doses given at 12-h intervals for 8 days. these are the approved, and commonly used but unapproved, feed additive doses, respectively, in the united states for the prevention of ovine infectious abortion. blood samples were collected just prior to dosing at 0, 12, 24, 72, 96, ...201425131164
expansion of the apc superfamily of secondary carriers.the amino acid-polyamine-organocation (apc) superfamily is the second largest superfamily of secondary carriers currently known. in this study, we establish homology between previously recognized apc superfamily members and proteins of seven new families. these families include the paap (putative amino acid permease), livcs (branched chain amino acid:cation symporter), nramp (natural resistance-associated macrophage protein), csta (carbon starvation a protein), kup (k⁺ uptake permease), bene (be ...201425043943
cytolethal distending toxins require components of the er-associated degradation pathway for host cell entry.intracellular acting protein exotoxins produced by bacteria and plants are important molecular determinants that drive numerous human diseases. a subset of these toxins, the cytolethal distending toxins (cdts), are encoded by several gram-negative pathogens and have been proposed to enhance virulence by allowing evasion of the immune system. cdts are trafficked in a retrograde manner from the cell surface through the golgi apparatus and into the endoplasmic reticulum (er) before ultimately reach ...201425078082
identification of the genes that contribute to lactate utilization in helicobacter pylori.helicobacter pylori are gram-negative, spiral-shaped microaerophilic bacteria etiologically related to gastric cancer. lactate utilization has been implicated although no corresponding genes have been identified in the h. pylori genome. here, we report that gene products of hp0137-0139 (lldefg), hp0140-0141 (lctp), and hp1222 (dld) contribute to d- and l-lactate utilization in h. pylori. the three-gene unit hp0137-0139 in h. pylori 26695 encodes l-lactate dehydrogenase (ldh) that catalyzes the c ...201425078575
current perspectives on viable but non-culturable (vbnc) pathogenic bacteria.under stress conditions, many species of bacteria enter into starvation mode of metabolism or a physiologically viable but non-culturable (vbnc) state. several human pathogenic bacteria have been reported to enter into the vbnc state under these conditions. the pathogenic vbnc bacteria cannot be grown using conventional culture media, although they continue to retain their viability and express their virulence. though there have been debates on the vbnc concept in the past, several molecular stu ...201425133139
inflammation-related carcinogenesis: current findings in epidemiological trends, causes and mechanisms.inflammation is a definite cancer-causing factor as revealed by cumulative basic, clinical and epidemiological studies. it is mostly induced by infectious agents. for instance, infection with papillomaviruses associates with anogenital cancers, especially cervical cancers; helicobacter pylori infection of the stomach tends to increase the risk of stomach cancer; chronic hepatitis b & c viruses and fluke infections of the liver increase liver cancers; autoimmune diseases, e.g., inflammatory bowel ...201425324587
peripheral prion disease pathogenesis is unaltered in the absence of sialoadhesin (siglec-1/cd169).prions are a unique group of pathogens, which are considered to comprise solely of an abnormally folded isoform of the cellular prion protein. the accumulation and replication of prions within secondary lymphoid organs is important for their efficient spread from the periphery to the brain where they ultimately cause neurodegeneration and death. mononuclear phagocytes (mnp) play key roles in prion disease pathogenesis. some mnp appear to facilitate the propagation of prions to and within lymphoi ...201424684244
production of a recombinant vaccine candidate against burkholderia pseudomallei exploiting the bacterial n-glycosylation machinery.vaccines developing immune responses toward surface carbohydrates conjugated to proteins are effective in preventing infection and death by bacterial pathogens. traditional production of these vaccines utilizes complex synthetic chemistry to acquire and conjugate the glycan to a protein. however, glycoproteins produced by bacterial protein glycosylation systems are significantly easier to produce, and could possible be used as vaccine candidates. in this work, we functionally expressed the burkh ...201425120536
antimicrobial peptide resistance of vibrio cholerae results from an lps modification pathway related to nonribosomal peptide synthetases.the current pandemic el tor biotype of o1 vibrio cholerae is resistant to polymyxins, whereas the previous pandemic strain of the classical biotype is polymyxin sensitive. the almefg operon found in el tor v. cholerae confers >100-fold resistance to polymyxins through the glycylation of lipopolysaccharide. here, we present the mechanistic determination of initial steps in the almefg pathway. we verify that almf is an aminoacyl carrier protein and identify alme as the enzyme required to activate ...201425068415
detection of intermediates in the oxidative half-reaction of the fad-dependent thymidylate synthase from thermotoga maritima: carbon transfer without covalent pyrimidine activation.thymidylate, a vital dna precursor, is synthesized by thymidylate synthases (tss). a second class of tss, encoded by the thyx gene, is found in bacteria and a few other microbes and is especially widespread in anaerobes. ts encoded by thyx requires a flavin adenine dinucleotide prosthetic group for activity. in the oxidative half-reaction, the reduced flavin is oxidized by 2'-deoxyuridine 5'-monophosphate (dump) and (6r)-n5,n10-methylene-5,6,7,8-tetrahydrofolate (ch2thf), synthesizing 2'-deoxyth ...201425068636
mycoplasma pneumoniae infection with neurologic complications.extrapulmonary complications of mycoplasma pneumoniae (m. pneumoniae) infection include encephalitis, optic neuritis, acute psychosis, stroke, cranial nerve palsies, aseptic meningitis and also it may be implicated in immune mediated neurological diseases such as acute demyelinating encephalomyelitis, guillain-barre syndrome and transverse myelitis.201425793076
a large community outbreak of gastroenteritis associated with consumption of drinking water contaminated by river water, belgium, 2010.summary on 6 december 2010 a fire in hemiksem, belgium, was extinguished by the fire brigade with both river water and tap water. local physicians were asked to report all cases of gastroenteritis. we conducted a retrospective cohort study among 1000 randomly selected households. we performed a statistical and geospatial analysis. human stool samples, tap water and river water were tested for pathogens. of the 1185 persons living in the 528 responding households, 222 (18·7%) reported symptoms of ...201425062494
a large community outbreak of gastroenteritis associated with consumption of drinking water contaminated by river water, belgium, 2010.summary on 6 december 2010 a fire in hemiksem, belgium, was extinguished by the fire brigade with both river water and tap water. local physicians were asked to report all cases of gastroenteritis. we conducted a retrospective cohort study among 1000 randomly selected households. we performed a statistical and geospatial analysis. human stool samples, tap water and river water were tested for pathogens. of the 1185 persons living in the 528 responding households, 222 (18·7%) reported symptoms of ...201425062494
enteric dysbiosis promotes antibiotic-resistant bacterial infection: systemic dissemination of resistant and commensal bacteria through epithelial transcytosis.antibiotic usage promotes intestinal colonization of antibiotic-resistant bacteria. however, whether resistant bacteria gain dominance in enteric microflora or disseminate to extraintestinal viscera remains unclear. our aim was to investigate temporal diversity changes in microbiota and transepithelial routes of bacterial translocation after antibiotic-resistant enterobacterial colonization. mice drinking water with or without antibiotics were intragastrically gavaged with ampicillin-resistant ( ...201425059827
metagenomic identification of a novel salt tolerance gene from the human gut microbiome which encodes a membrane protein with homology to a brp/blh-family β-carotene 15,15'-monooxygenase.the human gut microbiome consists of at least 3 million non-redundant genes, 150 times that of the core human genome. herein, we report the identification and characterisation of a novel stress tolerance gene from the human gut metagenome. the locus, assigned brpa, encodes a membrane protein with homology to a brp/blh-family β-carotene monooxygenase. cloning and heterologous expression of brpa in escherichia coli confers a significant salt tolerance phenotype. furthermore, when cultured in the p ...201425058308
cytotoxic and pathogenic properties of klebsiella oxytoca isolated from laboratory animals.klebsiella oxytoca is an opportunistic pathogen implicated in various clinical diseases in animals and humans. studies suggest that in humans k. oxytoca exerts its pathogenicity in part through a cytotoxin. however, cytotoxin production in animal isolates of k. oxytoca and its pathogenic properties have not been characterized. furthermore, neither the identity of the toxin nor a complete repertoire of genes involved in k. oxytoca pathogenesis have been fully elucidated. here, we showed that seve ...201425057966
burden of diarrhea, hospitalization and mortality due to cryptosporidial infections in indian children.cryptosporidium spp. is a common, but under-reported cause of childhood diarrhea throughout the world, especially in developing countries. a comprehensive estimate of the burden of cryptosporidiosis in resource-poor settings is not available.201425058664
a systematic proteomic analysis of listeria monocytogenes house-keeping protein secretion systems.listeria monocytogenes is a firmicute bacterium causing serious infections in humans upon consumption of contaminated food. most of its virulence factors are secretory proteins either released to the medium or attached to the bacterial surface. l. monocytogenes encodes at least six different protein secretion pathways. although great efforts have been made in the past to predict secretory proteins and their secretion routes using bioinformatics, experimental evidence is lacking for most secretio ...201425056936
uncomplicated urinary tract infections and antibiotic resistance-epidemiological and mechanistic aspects.uncomplicated urinary tract infections are typically monobacterial and are predominantly caused by escherichia coli. although several effective treatment options are available, the rates of antibiotic resistance in urinary isolates of e. coli have increased during the last decade. knowledge of the actual local rates of antibiotic resistant pathogens as well as the underlying mechanisms are important factors in addition to the geographical location and the health state of the patient for choosing ...201427025749
identification of glutamate abc-transporter component in clostridium perfringens as a putative drug target.clostridium perfringens is an anaerobic pathogen known to cause vast number of diseases in mammals and birds. various toxins and hydrolysing enzymes released by the organism are responsible for the necrosis of soft tissues. due to serious safety issues associated with current vaccines against c. perfringens, there is a need for new drug or vaccine targets. c. perfringens is extremely dependent on its host for nutrition which can be targeted for vaccine development or drug design. therefore, it i ...201425187678
nitrosylation mechanisms of mycobacterium tuberculosis and campylobacter jejuni truncated hemoglobins n, o, and p.truncated hemoglobins (trhbs) are widely distributed in bacteria and plants and have been found in some unicellular eukaryotes. phylogenetic analysis based on protein sequences shows that trhbs branch into three groups, designated n (or i), o (or ii), and p (or iii). most trhbs are involved in the o2/no chemistry and/or oxidation/reduction function, permitting the survival of the microorganism in the host. here, a detailed comparative analysis of kinetics and/or thermodynamics of (i) ferrous myc ...201425051055
structure of a membrane-embedded prenyltransferase homologous to ubiad1.membrane-embedded prenyltransferases from the ubia family catalyze the mg2+-dependent transfer of a hydrophobic polyprenyl chain onto a variety of acceptor molecules and are involved in the synthesis of molecules that mediate electron transport, including vitamin k and coenzyme q. in humans, missense mutations to the protein ubia prenyltransferase domain-containing 1 (ubiad1) are responsible for schnyder crystalline corneal dystrophy, which is a genetic disease that causes blindness. mechanistic ...201425051182
human milk contains novel glycans that are potential decoy receptors for neonatal rotaviruses.human milk contains a rich set of soluble, reducing glycans whose functions and bioactivities are not well understood. because human milk glycans (hmgs) have been implicated as receptors for various pathogens, we explored the functional glycome of human milk using shotgun glycomics. the free glycans from pooled milk samples of donors with mixed lewis and secretor phenotypes were labeled with a fluorescent tag and separated via multidimensional hplc to generate a tagged glycan library containing ...201425048705
ai-2 of aggregatibacter actinomycetemcomitans inhibits candida albicans biofilm formation.aggregatibacter actinomycetemcomitans, a gram-negative bacterium, and candida albicans, a polymorphic fungus, are both commensals of the oral cavity but both are opportunistic pathogens that can cause oral diseases. a. actinomycetemcomitans produces a quorum-sensing molecule called autoinducer-2 (ai-2), synthesized by luxs, that plays an important role in expression of virulence factors, in intra- but also in interspecies communication. the aim of this study was to investigate the role of ai-2 b ...201425101248
genome sequencing of multidrug resistant novel clostridium sp. bl8 reveals its potential for pathogenicity.the human gut microbiome is important for maintaining the health status of the host. clostridia are key members of the human gut microbiome, carrying out several important functions in the gut environment. hence understanding the role of different clostridium species isolated from human gut is essential. the present study was aimed at investigating the role of novel clostridium sp. isolate bl8 in human gut using genome sequencing as a tool.201425076986
regime shift in sandy beach microbial communities following deepwater horizon oil spill remediation efforts.sandy beaches support a wide variety of underappreciated biodiversity that is critical to coastal ecosystems. prior to the 2010 deepwater horizon oil spill, the diversity and function of supratidal beach sediment microbial communities along gulf of mexico coastlines were not well understood. as such, it was unclear if microbial community compositional changes would occur following exposure to beached oil, if indigenous communities could biodegrade oil, or how cleanup efforts, such as sand washin ...201425036744
hiv-1 capture and transmission by dendritic cells: the role of viral glycolipids and the cellular receptor siglec-1.dendritic cells (dcs) are essential in order to combat invading viruses and trigger antiviral responses. paradoxically, in the case of hiv-1, dcs might contribute to viral pathogenesis through trans-infection, a mechanism that promotes viral capture and transmission to target cells, especially after dc maturation. in this review, we highlight recent evidence identifying sialyllactose-containing gangliosides in the viral membrane and the cellular lectin siglec-1 as critical determinants for hiv-1 ...201425033082
a novel mouse model of campylobacter jejuni gastroenteritis reveals key pro-inflammatory and tissue protective roles for toll-like receptor signaling during infection.campylobacter jejuni is a major source of foodborne illness in the developed world, and a common cause of clinical gastroenteritis. exactly how c. jejuni colonizes its host's intestines and causes disease is poorly understood. although it causes severe diarrhea and gastroenteritis in humans, c. jejuni typically dwells as a commensal microbe within the intestines of most animals, including birds, where its colonization is asymptomatic. pretreatment of c57bl/6 mice with the antibiotic vancomycin f ...201425033044
gpr107, a g-protein-coupled receptor essential for intoxication by pseudomonas aeruginosa exotoxin a, localizes to the golgi and is cleaved by furin.a number of toxins, including exotoxin a (pe) of pseudomonas aeruginosa, kill cells by inhibiting protein synthesis. pe kills by adp-ribosylation of the translation elongation factor 2, but many of the host factors required for entry, membrane translocation, and intracellular transport remain to be elucidated. a genome-wide genetic screen in human kbm7 cells was performed to uncover host factors used by pe, several of which were confirmed by crispr/cas9-gene editing in a different cell type. sev ...201425031321
the yersinia pestis siderophore, yersiniabactin, and the znuabc system both contribute to zinc acquisition and the development of lethal septicaemic plague in mice.bacterial pathogens must overcome host sequestration of zinc (zn(2+) ), an essential micronutrient, during the infectious disease process. while the mechanisms to acquire chelated zn(2+) by bacteria are largely undefined, many pathogens rely upon the znuabc family of abc transporters. here we show that in yersinia pestis, irp2, a gene encoding the synthetase (hmwp2) for the siderophore yersiniabactin (ybt) is required for growth under zn(2+) -deficient conditions in a strain lacking znuabc. more ...201424979062
emerging and re-emerging zoonoses of dogs and cats.since the middle of the 20th century, pets are more frequently considered as "family members" within households. however, cats and dogs still can be a source of human infection by various zoonotic pathogens. among emerging or re-emerging zoonoses, viral diseases, such as rabies (mainly from dog pet trade or travel abroad), but also feline cowpox and newly recognized noroviruses or rotaviruses or influenza viruses can sicken our pets and be transmitted to humans. bacterial zoonoses include bacter ...201426480316
inflammatory myofibroblastic tumor of the bladder - an unexpected case coexisting with an ovarian teratoma.inflammatory myofibroblastic tumors (imts) mainly occur in children and young adults, usually in the first two decades of life. imt-type tumors belong to neoplasms of an intermediate biologic potential with considerable rate of local recurrence and in some cases that able to create metastases. presented case is the first imt coexisting with the other neoplasm. in our paper we are going to present a peculiar case of an imt of the bladder coexisting with an ovarian teratoma, and to discuss its pat ...201425027562
a crispr-cas system enhances envelope integrity mediating antibiotic resistance and inflammasome evasion.clustered, regularly interspaced, short palindromic repeats-crispr associated (crispr-cas) systems defend bacteria against foreign nucleic acids, such as during bacteriophage infection and transformation, processes which cause envelope stress. it is unclear if these machineries enhance membrane integrity to combat this stress. here, we show that the cas9-dependent crispr-cas system of the intracellular bacterial pathogen francisella novicida is involved in enhancing envelope integrity through th ...201425024199
genotypes and antibiotic resistances of campylobacter jejuni isolates from cattle and pigeons in dairy farms.campylobacter jejuni is the most common food-borne zoonotic pathogen causing human gastroenteritis worldwide and has assumed more importance in italy following the increased consumption of raw milk. our objectives were to get an overview of genotypes and antibiotic resistances in c. jejuni isolated from milk, cattle feces, and pigeons in dairy herds of northern italy. flab-typing was applied to 78 c. jejuni isolates, previously characterized by multi-locus sequence typing, and genotypic resistan ...201425026083
bacterial foodborne infections after hematopoietic cell transplantation.diarrhea, abdominal pain, and fever are common among patients undergoing hematopoietic cell transplantation (hct), but such symptoms are also typical with foodborne infections. the burden of disease caused by foodborne infections in patients undergoing hct is unknown. we sought to describe bacterial foodborne infection incidence after transplantation within a single-center population of hct recipients. all hct recipients who underwent transplantation from 2001 through 2011 at the fred hutchinson ...201425020101
effect of commensals and probiotics on visceral sensitivity and pain in irritable bowel syndrome.the last ten years' wide progress in the gut microbiota phylogenetic and functional characterization has been made evidencing dysbiosis in several gastrointestinal diseases including inflammatory bowel diseases and irritable bowel syndrome (ibs). ibs is a functional gut disease with high prevalence and negative impact on patient's quality of life characterized mainly by visceral pain and/or discomfort, representing a good paradigm of chronic gut hypersensitivity. the ibs features are strongly re ...201425184834
structure of the ldcb ld-carboxypeptidase reveals the molecular basis of peptidoglycan recognition.peptidoglycan surrounds the bacterial cytoplasmic membrane to protect the cell against osmolysis. the biosynthesis of peptidoglycan, made of glycan strands crosslinked by short peptides, is the target of antibiotics like β-lactams and glycopeptides. nascent peptidoglycan contains pentapeptides that are trimmed by carboxypeptidases to tetra- and tripeptides. the well-characterized dd-carboxypeptidases hydrolyze the terminal d-alanine from the stem pentapeptide to produce a tetrapeptide. however, ...201424909784
impact of acinetobacter baumannii superoxide dismutase on motility, virulence, oxidative stress resistance and susceptibility to antibiotics.acinetobacter baumannii is a gram-negative bacterium appearing as an opportunistic pathogen in hospital settings. superoxide dismutase (sod) contributes to virulence in several pathogenic bacteria by detoxifying reactive oxygen species released in the course of host defense reactions. however, the biological role of sods in a. baumannii has not yet been elucidated. here, we inactivated in a. baumannii atcc 17978 gene a1s_2343, encoding a putative sod of the fe-mn type by transposon insertion, re ...201425000585
mathematical and live meningococcal models for simple sequence repeat dynamics - coherent predictions and observations.evolvability by means of simple sequence repeat (ssr) instability is a feature under the constant influence of opposing selective pressures to expand and compress the repeat tract and is mechanistically influenced by factors that affect genetic instability. in addition to direct selection for protein expression and structural integrity, other factors that influence tract length evolution were studied. the genetic instability of ssrs that switch the expression of antibiotic resistance on and off ...201424999629
top-down strategies for the structural elucidation of intact gram-negative bacterial endotoxins.re-modelling of lipopolysaccharides, which are the primary constituent of the outer cell membrane of gram-negative bacteria, modulates pathogenesis and resistance to microbials. reported herein is the characterization of intact gram-negative bacterial lipooligosaccharides (los) via a new strategy utilizing online liquid chromatography (lc) coupled with ultraviolet photodissociation (uvpd) mass spectrometry. compared to collision-based ms/ms methods, uvpd and uvpd/hcd promoted a greater array of ...201425386333
the interplay between siglecs and sialylated pathogens.siglecs are mammalian sialic acid (sia) recognizing immunoglobulin-like receptors expressed across the major leukocyte lineages, and function to recognize ubiquitous sia epitopes on cell surface glycoconjugates and regulate immunological and inflammatory activities of these cells. a large subset referred to as cd33-related siglecs are inhibitory receptors that limit leukocyte activation, and recent research has shown that the pathogen group b streptococcus (gbs) binds to these siglecs in sia- an ...201424996821
host stress hormone norepinephrine stimulates pneumococcal growth, biofilm formation and virulence gene expression.host signals are being shown to have a major impact on the bacterial phenotype. one of them is the endogenously produced catecholamine stress hormones, which are also used therapeutically as inotropes. recent work form our laboratories have found that stress hormones can markedly increase bacterial growth and virulence. this report reveals that streptococcus pneumoniae, a commensal that can also be a major cause of community acquired and nosocomial pneumonia, is highly inotrope responsive. thera ...201424996423
probiotic potential of lactobacillus strains with antimicrobial activity against some human pathogenic strains.the objective of this study was to isolate, identify, and characterize some lactic acid bacterial strains from human milk, infant feces, and fermented grapes and dates, as potential probiotics with antimicrobial activity against some human pathogenic strains. one hundred and forty bacterial strains were isolated and, after initial identification and a preliminary screening for acid and bile tolerance, nine of the best isolates were selected and further identified using 16 s rrna gene sequences. ...201425105147
tupa: a tungstate binding protein in the periplasm of desulfovibrio alaskensis g20.the tupabc system is involved in the cellular uptake of tungsten and belongs to the abc (atp binding cassette)-type transporter systems. the tupa component is a periplasmic protein that binds tungstate anions, which are then transported through the membrane by the tupb component using atp hydrolysis as the energy source (the reaction catalyzed by the modc component). we report the heterologous expression, purification, determination of affinity binding constants and crystallization of the desulf ...201424992597
population heterogeneity and dynamics in starter culture and lag phase adaptation of the spoilage yeast zygosaccharomyces bailii to weak acid preservatives.the food spoilage yeast zygosaccharomyces bailii shows great resistance to weak-acid preservatives, including sorbic acid (2, 4-hexadienoic acid). that extreme resistance was shown to be due to population heterogeneity, with a small sub-population of cells resistant to a variety of weak acids, probably caused by a lower internal ph reducing the uptake of all weak acids. in the present paper, it was found that resistant cells were extremely rare in exponential cultures, but increased by up to 800 ...201424813627
the mucus and mucins of the goblet cells and enterocytes provide the first defense line of the gastrointestinal tract and interact with the immune system.the gastrointestinal tract is covered by mucus that has different properties in the stomach, small intestine, and colon. the large highly glycosylated gel-forming mucins muc2 and muc5ac are the major components of the mucus in the intestine and stomach, respectively. in the small intestine, mucus limits the number of bacteria that can reach the epithelium and the peyer's patches. in the large intestine, the inner mucus layer separates the commensal bacteria from the host epithelium. the outer co ...201424942678
conservation of transcription start sites within genes across a bacterial genus.transcription start sites (tsss) lying inside annotated genes, on the same or opposite strand, have been observed in diverse bacteria, but the function of these unexpected transcripts is unclear. here, we use the metal-reducing bacterium shewanella oneidensis mr-1 and its relatives to study the evolutionary conservation of unexpected tsss. using high-resolution tiling microarrays and 5'-end rna sequencing, we identified 2,531 tsss in s. oneidensis mr-1, of which 18% were located inside coding se ...201424987095
campylobacter jejuni is not merely a commensal in commercial broiler chickens and affects bird welfare.campylobacter jejuni is the leading cause of bacterial food-borne infection; chicken meat is its main source. c. jejuni is considered commensal in chickens based on experimental models unrepresentative of commercial production. here we show that the paradigm of campylobacter commensalism in the chicken is flawed. through experimental infection of four commercial breeds of broiler chickens, we show that breed has a significant effect on c. jejuni infection and the immune response of the animals, ...201424987092
3,4-dhpea-ea from olea europaea l. is effective against standard and clinical isolates of staphylococcus sp.the aim of the present work was to evaluate the antibacterial effect of 3,4-dhpea-ea (methyl-4-(2-(3,4-dihydroxyphenethoxy)-2-oxoethyl)-3-formyl-2-methyl-3,4-dihydro-2h-pyran-5-carboxylate), a derivate of oleuropein, against a range of gram-positive bacteria, including atcc strains, food and clinical isolates.201424986240
evaluation of three rapid diagnostic methods for direct identification of microorganisms in positive blood cultures.the identification of organisms from positive blood cultures generally takes several days. however, recently developed rapid diagnostic methods offer the potential for organism identification within only a few hours of blood culture positivity. in this study, we evaluated the performance of three commercial methods to rapidly identify organisms directly from positive blood cultures: quickfish (advandx, wolburn, ma), verigene gram-positive blood culture (bc-gp; nanosphere, northbrook, il), and ma ...201424808235
defects in phosphate acquisition and storage influence virulence of cryptococcus neoformans.nutrient acquisition and sensing are critical aspects of microbial pathogenesis. previous transcriptional profiling indicated that the fungal pathogen cryptococcus neoformans, which causes meningoencephalitis in immunocompromised individuals, encounters phosphate limitation during proliferation in phagocytic cells. we therefore tested the hypothesis that phosphate acquisition and polyphosphate metabolism are important for cryptococcal virulence. deletion of the high-affinity uptake system interf ...201424711572
anti-diarrhoeal investigation from aqueous extract of cuminum cyminum linn. seed in albino rats.cuminum cyminum linn. (umbelliferae), commonly known as jeera. it is native from mediterranean region, but today widely cultivated in asian countries. it has been reported to possess various medicinal properties and an important food ingredient. the seed of the plant are claimed for treatment of diarrhoea by various traditional practitioners.201425002800
epidemiology of pathogenic enterobacteria in humans, livestock, and peridomestic rodents in rural madagascar.among the families of enteric bacteria are globally important diarrheal agents. despite their potential for zoonotic and environmental transmission, few studies have examined the epidemiology of these pathogens in rural systems characterized by extensive overlap among humans, domesticated and peridomestic animals. we investigated patterns of infection with enterotoxigenic escherichia coli, shigella spp., salmonella enterica, vibrio cholerae, and yersinia spp. (enterocolitica, and pseudotuberculo ...201424983990
beyond the matrix-assisted laser desorption ionization (maldi) biotyping workflow: in search of microorganism-specific tryptic peptides enabling discrimination of subspecies.a well-accepted method for identification of microorganisms uses matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) coupled to analysis software which identifies and classifies the organism according to its ribosomal protein spectral profile. the method, called maldi biotyping, is widely used in clinical diagnostics and has partly replaced conventional microbiological techniques such as biochemical identification due to its shorter time to result (minutes ...201424795381
emergence of high-level azithromycin resistance in campylobacter jejuni isolates from pediatric diarrhea patients in kolkata, india. 201424777098
analysis of surface-exposed outer membrane proteins in helicobacter pylori.more than 50 helicobacter pylori genes are predicted to encode outer membrane proteins (omps), but there has been relatively little experimental investigation of the h. pylori cell surface proteome. in this study, we used selective biotinylation to label proteins localized to the surface of h. pylori, along with differential detergent extraction procedures to isolate proteins localized to the outer membrane. proteins that met multiple criteria for surface-exposed outer membrane localization incl ...201424769695
a molecular survey of campylobacter jejuni and campylobacter coli virulence and diversity.the aim of this study was to determine the prevalence of virulence-associated genes and enterobacterial repetitive intergenic consensus pcr (eric-pcr) analysis of campylobacter spp. isolated from children with diarrhea in iran.201424842142
inhibiting helicobacter pylori htra protease by addressing a computationally predicted allosteric ligand binding site.helicobacter pylori is associated with inflammatory diseases and can cause gastric cancer and mucosa-associated lymphoma. one of the bacterium's key proteins is high temperature requirement a (hphtra) protein, an extracellular serine protease that cleaves e-cadherin of gastric epithelial cells, which leads to loss of cell-cell adhesion. inhibition of hphtra may constitute an intervention strategy against h. pylori infection. guided by the computational prediction of hypothetical ligand binding s ...201426819700
carbohydrate-mimetic peptides for pan anti-tumor responses.molecular mimicry is fundamental to biology and transcends to many disciplines ranging from immune pathology to drug design. structural characterization of molecular partners has provided insight into the origins and relative importance of complementarity in mimicry. chemical complementarity is easy to understand; amino acid sequence similarity between peptides, for example, can lead to cross-reactivity triggering similar reactivity from their cognate receptors. however, conformational complemen ...201425071769
contamination of water resources by pathogenic bacteria.water-borne pathogen contamination in water resources and related diseases are a major water quality concern throughout the world. increasing interest in controlling water-borne pathogens in water resources evidenced by a large number of recent publications clearly attests to the need for studies that synthesize knowledge from multiple fields covering comparative aspects of pathogen contamination, and unify them in a single place in order to present and address the problem as a whole. providing ...201425006540
detection of diarrhoeagenic escherichia coli in clinical and environmental water sources in south africa using single-step 11-gene m-pcr.escherichia coli (e. coli) consists of commensal (comec) and diarrhoeagenic (dec) groups. comec are detected using traditional culture methods. conformational steps are performed after culturing if it is required to test for the presence of dec, increasing cost and time in obtaining the results. the aim of this study was to develop a single-step multiplex polymerase chain reaction (m-pcr) that can simultaneously amplify genes associated with dec and comec, with the inclusion of controls to monit ...201424969140
diarrhea in young children from low-income countries leads to large-scale alterations in intestinal microbiota composition.diarrheal diseases continue to contribute significantly to morbidity and mortality in infants and young children in developing countries. there is an urgent need to better understand the contributions of novel, potentially uncultured, diarrheal pathogens to severe diarrheal disease, as well as distortions in normal gut microbiota composition that might facilitate severe disease.201424995464
unrest at home: diarrheal disease and microbiota disturbance.diarrhea and malnutrition, two intertwined worldwide problems, are both associated with lower diversity of the intestinal microbiota in children in low-income countries.201425002208
proteomic and genomic analysis reveals novel campylobacter jejuni outer membrane proteins and potential heterogeneity.gram-negative bacterial outer membrane proteins play important roles in the interaction of bacteria with their environment including nutrient acquisition, adhesion and invasion, and antibiotic resistance. in this study we identified 47 proteins within the sarkosyl-insoluble fraction of campylobacter jejuni 81-176, using lc-esi-ms/ms. comparative analysis of outer membrane protein sequences was visualised to reveal protein distribution within a panel of campylobacter spp., identifying several c. ...201427525220
a genomic island integrated into reca of vibrio cholerae contains a divergent reca and provides multi-pathway protection from dna damage.lateral gene transfer (lgt) has been crucial in the evolution of the cholera pathogen, vibrio cholerae. the two major virulence factors are present on two different mobile genetic elements, a bacteriophage containing the cholera toxin genes and a genomic island (gi) containing the intestinal adhesin genes. non-toxigenic v. cholerae in the aquatic environment are a major source of novel dna that allows the pathogen to morph via lgt. in this study, we report a novel gi from a non-toxigenic v. chol ...201424889424
a genomic island integrated into reca of vibrio cholerae contains a divergent reca and provides multi-pathway protection from dna damage.lateral gene transfer (lgt) has been crucial in the evolution of the cholera pathogen, vibrio cholerae. the two major virulence factors are present on two different mobile genetic elements, a bacteriophage containing the cholera toxin genes and a genomic island (gi) containing the intestinal adhesin genes. non-toxigenic v. cholerae in the aquatic environment are a major source of novel dna that allows the pathogen to morph via lgt. in this study, we report a novel gi from a non-toxigenic v. chol ...201424889424
sensitization of radio-resistant prostate cancer cells with a unique cytolethal distending toxin.cytolethal distending toxin (cdt) produced by campylobacter jejuni is a genotoxin that induces cell-cycle arrest and apoptosis in mammalian cells. recent studies have demonstrated that prostate cancer (pca) cells can acquire radio-resistance when doc-2/dab2 interactive protein (dab2ip) is downregulated. in this study, we showed that cdt could induce cell death in dab2ip-deficient pca cells. a combination of cdt and radiotherapy significantly elicited cell death in dab2ip-deficient pca cells by i ...201425015118
high-level antimicrobial efficacy of representative mediterranean natural plant extracts against oral microorganisms.nature is an unexplored reservoir of novel phytopharmaceuticals. since biofilm-related oral diseases often correlate with antibiotic resistance, plant-derived antimicrobial agents could enhance existing treatment options. therefore, the rationale of the present report was to examine the antimicrobial impact of mediterranean natural extracts on oral microorganisms. five different extracts from olea europaea, mastic gum, and inula viscosa were tested against ten bacteria and one candida albicans s ...201425054150
dissecting escherichia coli outer membrane biogenesis using differential proteomics.the cell envelope of gram-negative bacteria is a complex multi-layered structure comprising an inner cytoplasmic membrane and an additional asymmetric lipid bilayer, the outer membrane, which functions as a selective permeability barrier and is essential for viability. lipopolysaccharide, an essential glycolipid located in the outer leaflet of the outer membrane, greatly contributes to the peculiar properties exhibited by the outer membrane. this complex molecule is transported to the cell surfa ...201424967819
antimicrobial edible films and coatings for meat and meat products preservation.animal origin foods are widely distributed and consumed around the world due to their high nutrients availability but may also provide a suitable environment for growth of pathogenic and spoilage microorganisms. nowadays consumers demand high quality food with an extended shelf life without chemical additives. edible films and coatings (efc) added with natural antimicrobials are a promising preservation technology for raw and processed meats because they provide good barrier against spoilage and ...201425050387
novel components of the flagellar system in epsilonproteobacteria.motility is essential for the pathogenesis of many bacterial species. most bacteria move using flagella, which are multiprotein filaments that rotate propelled by a cell wall-anchored motor using chemical energy. although some components of the flagellar apparatus are common to many bacterial species, recent studies have shown significant differences in the flagellar structures of different bacterial species. the molecular bases for these differences, however, are not understood. the flagella fr ...201424961693
case of acute pancreatitis associated with campylobacter enteritis.a 25-year-old man was admitted with the chief complaints of right flank pain, watery diarrhea, and fever. blood tests revealed high levels of inflammatory markers, and infectious enteritis was diagnosed. a stool culture obtained on admission revealed no growth of any significant pathogens. conservative therapy was undertaken with fasting and fluid replacement. on day 2 of admission, the fever resolved, the frequency of defecation reduced, the right flank pain began to subside, and the white bloo ...201424966623
antiretroviral therapy (art) use, human immunodeficiency virus (hiv)-1 rna suppression, and medical causes of hospitalization among hiv-infected intravenous drug users in the late art era.antiretroviral therapy (art) has reduced the rates and changed the causes of hospital admission. however, human immunodeficiency virus-positive intravenous drug users (hiv-idu) continue to have increased hospitalizations and discharge diagnosis are less defined in the late art era. our aim was to examine art use, hiv-1 rna suppression, and hospital discharge diagnoses among hiv-idu admitted to an urban hospital.201425734084
draft genome sequence of enterococcus faecalis mb5259.in this study, we present a draft genome sequence of enterococcus faecalis mb5259, a promising probiotic strain. the identified differences and common features between this strain and reference strains will assist in better understanding the mechanism of antibacterial action and in developing novel probiotics.201424948775
cultivable bacterial microbiota of northern bobwhite (colinus virginianus): a new reservoir of antimicrobial resistance?the northern bobwhite (colinus virginianus) is an ecologically and economically important avian species. at the present time, little is known about the microbial communities associated with these birds. as the first step to create a quail microbiology knowledge base, the current study conducted an inventory of cultivable quail tracheal, crop, cecal, and cloacal microbiota and associated antimicrobial resistance using a combined bacteriology and dna sequencing approach. a total of 414 morphologic ...201424937705
comparative analysis of the primary transcriptome of synechocystis sp. pcc 6803.rna-seq and especially differential rna-seq-type transcriptomic analyses (drna-seq) are powerful analytical tools, as they not only provide insights into gene expression changes but also provide detailed information about all promoters active at a given moment, effectively giving a deep insight into the transcriptional landscape. synechocystis sp. pcc 6803 (synechocystis 6803) is a unicellular model cyanobacterium that is widely used in research fields from ecology, photophysiology to systems bi ...201424935866
functional identification of a galactosyltransferase critical to bacteroides fragilis capsular polysaccharide a biosynthesis.capsular polysaccharide a (cpsa), a polymer of a four-sugar repeating unit that coats the surface of the mammalian symbiont bacteroides fragilis, has therapeutic potential in animal models of multiple sclerosis and other autoinflammatory diseases. genetic studies have demonstrated that cpsa biosynthesis is dependent primarily on a single gene cluster within the b. fragilis genome. however, the precise functions of the individual glycosyltransferases encoded by this cluster have not been identifi ...201424997288
the microbiota-gut-brain axis in functional gastrointestinal disorders.functional gastrointestinal disorders (fgids) are highly prevalent and pose a significant burden on health care and society, and impact patients' quality of life. fgids comprise a heterogeneous group of disorders, with unclear underlying pathophysiology. they are considered to result from the interaction of altered gut physiology and psychological factors via the gut-brain axis, where brain and gut symptoms are reciprocally influencing each other's expression. intestinal microbiota, as a part of ...201424921926
role of campylobacter jejuni gamma-glutamyl transpeptidase on epithelial cell apoptosis and lymphocyte proliferation.a gamma-glutamyl transpeptidase (ggt) is produced by up to 31% of strains of campylobacter jejuni isolates. c. jejuni ggt is close to helicobacter pylori ggt suggesting a conserved activity but unlike the latter, c. jejuni ggt has not been studied extensively. in line with the data available for h. pylori, our objectives were to purify c. jejuni ggt from the bacteria, and to evaluate its inhibitory and proapoptotic activities on epithelial cells and human lymphocytes.201424995041
milk oligosaccharides over time of lactation from different dog breeds.the partnership of humans and dogs goes back to over 10'000 years, yet relatively little is known about a dog's first extra-uterine nutrition particularly when it comes to milk oligosaccharides. we set out to identify and quantify milk oligosaccharides over the course of lactation from different dog breeds (labrador retriever, schnauzer and 3 alaskan husky crossbreeds). to this end, 2 different chromatographic methods with fluorescence and mass spectrometry detection were developed and one was v ...201424924915
the cytolethal distending toxin effects on mammalian cells: a dna damage perspective.the cytolethal distending toxin (cdt) is produced by many pathogenic gram-negative bacteria and is considered as a virulence factor. in human cells, cdt exposure leads to a unique cytotoxicity associated with a characteristic cell distension and induces a cell cycle arrest dependent on the dna damage response (ddr) triggered by dna double-strand breaks (dsbs). cdt has thus been classified as a cyclomodulin and a genotoxin. whereas unrepaired damage can lead to cell death, effective, but improper ...201424921185
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