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rna-seq based identification and mutant validation of gene targets related to ethanol resistance in cyanobacterial synechocystis sp. pcc 6803. 201223259593
insights into the crispr/cas system of gardnerella vaginalis.gardnerella vaginalis is identified as the predominant colonist of the vaginal tracts of women diagnosed with bacterial vaginosis (bv). g. vaginalis can be isolated from healthy women, and an asymptomatic bv state is also recognised. the association of g. vaginalis with different clinical phenotypes could be explained by different cytotoxicity of the strains, presumably based on disparate gene content. the contribution of horizontal gene transfer to shaping the genomes of g. vaginalis is acknowl ...201223259527
a comparison of the endotoxin biosynthesis and protein oxidation pathways in the biogenesis of the outer membrane of escherichia coli and neisseria meningitidis.the gram-negative bacterial cell envelope consists of an inner membrane (im) that surrounds the cytoplasm and an asymmetrical outer-membrane (om) that forms a protective barrier to the external environment. the om consists of lipopolysaccahride (lps), phospholipids, outer membrane proteins (omps), and lipoproteins. oxidative protein folding mediated by periplasmic oxidoreductases is required for the biogenesis of the protein components, mainly constituents of virulence determinants such as pili, ...201223267440
multivalent glycoconjugates as anti-pathogenic agents.multivalency plays a major role in biological processes and particularly in the relationship between pathogenic microorganisms and their host that involves protein-glycan recognition. these interactions occur during the first steps of infection, for specific recognition between host and bacteria, but also at different stages of the immune response. the search for high-affinity ligands for studying such interactions involves the combination of carbohydrate head groups with different scaffolds and ...201223254759
multivalent glycoconjugates as anti-pathogenic agents.multivalency plays a major role in biological processes and particularly in the relationship between pathogenic microorganisms and their host that involves protein-glycan recognition. these interactions occur during the first steps of infection, for specific recognition between host and bacteria, but also at different stages of the immune response. the search for high-affinity ligands for studying such interactions involves the combination of carbohydrate head groups with different scaffolds and ...201223254759
hemoglobin: a nitric-oxide dioxygenase.members of the hemoglobin superfamily efficiently catalyze nitric-oxide dioxygenation, and when paired with native electron donors, function as no dioxygenases (nods). indeed, the nod function has emerged as a more common and ancient function than the well-known role in o2 transport-storage. novel hemoglobins possessing a nod function continue to be discovered in diverse life forms. unique hemoglobin structures evolved, in part, for catalysis with different electron donors. the mechanism of nod ...201224278729
"cross-glycosylation" of proteins in bacteroidales species.while it is now evident that the two bacteroidales species bacteroides fragilis and tannerella forsythia both have general o-glycosylation systems and share a common glycosylation sequon, the ability of these organisms to glycosylate a protein native to the other organism has not yet been demonstrated. here, we report on the glycosylation of heterologous proteins between these two organisms. using genetic tools previously developed for bacteroides species, two b. fragilis model glycoproteins wer ...201223258847
"cross-glycosylation" of proteins in bacteroidales species.while it is now evident that the two bacteroidales species bacteroides fragilis and tannerella forsythia both have general o-glycosylation systems and share a common glycosylation sequon, the ability of these organisms to glycosylate a protein native to the other organism has not yet been demonstrated. here, we report on the glycosylation of heterologous proteins between these two organisms. using genetic tools previously developed for bacteroides species, two b. fragilis model glycoproteins wer ...201223258847
induction of cytokines in different organs after intranasal inoculation of campylobacter jejuni in mice. 201223244595
first pillcam colon 2 capsule images of whipple's disease: case report and review of the literature.whipple's disease is a rare chronic systemic infection determined by the gram-positive bacillus tropheryma whipplei. the infection usually mainly involves the small bowel, but sometimes other organs are affected as well. since the current standard clinical and biological tests are nonspecific, diagnosis is very difficult and relies on histopathology. here we present the case of a 52-year-old man with chronic diarrhea and weight loss whose symptoms had been evolving for 2 years and whose diagnosi ...201223293729
factors that explain excretion of enteric pathogens by persons without diarrhea.excretion of enteropathogens by subjects without diarrhea influences our appreciation of the role of these pathogens as etiologic agents. characteristics of the pathogens and host and environmental factors help explain asymptomatic excretion of diarrheal pathogens by persons without diarrhea. after causing acute diarrhea followed by clinical recovery, some enteropathogens are excreted asymptomatically for many weeks. thus, in a prevalence survey of persons without diarrhea, some may be excreting ...201223169942
the global enteric multicenter study (gems): impetus, rationale, and genesis.diarrheal disease remains one of the top 2 causes of young child mortality in the developing world. whereas improvements in water/sanitation infrastructure and hygiene can diminish transmission of enteric pathogens, vaccines can also hasten the decline of diarrheal disease morbidity and mortality. from 1980 through approximately 2004, various case/control and small cohort studies were undertaken to address the etiology of pediatric diarrhea in developing countries. many studies had methodologica ...201223169934
laboratory diagnostic challenges in case/control studies of diarrhea in developing countries.case/control studies of acute infectious diarrhea require accurate and dependable laboratory tests to detect pathogens in samples from both symptomatic patients and healthy control subjects. the methods used to detect these pathogens have usually been evaluated on patient samples only, and their performance on samples from control subjects is mostly unknown. because many pathogens occur at a high overall frequency in developing countries and thus may be present in a notable proportion of control ...201223169943
miller fisher syndrome linked to norovirus infection.this is a case of miller fisher syndrome (mfs) linked to the norovirus syndrome. to our best knowledge, this is the first case report describing mfs associated with norovirus infection.201223242098
l-asparaginase ii produced by salmonella typhimurium inhibits t cell responses and mediates virulence.salmonella enterica serovar typhimurium avoids clearance by the host immune system by suppressing t cell responses; however, the mechanisms that mediate this immunosuppression remain unknown. we show that s. typhimurium inhibit t cell responses by producing l-asparaginase ii, which catalyzes the hydrolysis of l-asparagine to aspartic acid and ammonia. l-asparaginase ii is necessary and sufficient to suppress t cell blastogenesis, cytokine production, and proliferation and to downmodulate express ...201223245323
architecture of the major component of the type iii secretion system export apparatus.type iii secretion systems (t3sss) are bacterial membrane-embedded nanomachines designed to export specifically targeted proteins from the bacterial cytoplasm. secretion through t3ss is governed by a subset of inner membrane proteins termed the 'export apparatus'. we show that a key member of the shigella flexneri export apparatus, mxia, assembles into a ring essential for secretion in vivo. the ring-forming interfaces are well-conserved in both nonflagellar and flagellar homologs, implying that ...201223222644
architecture of the major component of the type iii secretion system export apparatus.type iii secretion systems (t3sss) are bacterial membrane-embedded nanomachines designed to export specifically targeted proteins from the bacterial cytoplasm. secretion through t3ss is governed by a subset of inner membrane proteins termed the 'export apparatus'. we show that a key member of the shigella flexneri export apparatus, mxia, assembles into a ring essential for secretion in vivo. the ring-forming interfaces are well-conserved in both nonflagellar and flagellar homologs, implying that ...201223222644
promising new assays and technologies for the diagnosis and management of infectious diseases.in the first decade of the 21st century, we have seen the completion of the human genome project and marked progress in the human microbiome project. the vast amount of data generated from these efforts combined with advances in molecular and biomedical technologies have led to the development of a multitude of assays and technologies that may be useful in the diagnosis and management of infectious diseases. here, we identify several new assays and technologies that have recently come into clini ...201223223587
promising new assays and technologies for the diagnosis and management of infectious diseases.in the first decade of the 21st century, we have seen the completion of the human genome project and marked progress in the human microbiome project. the vast amount of data generated from these efforts combined with advances in molecular and biomedical technologies have led to the development of a multitude of assays and technologies that may be useful in the diagnosis and management of infectious diseases. here, we identify several new assays and technologies that have recently come into clini ...201223223587
encephalitis and antibodies to dipeptidyl-peptidase-like protein-6, a subunit of kv4.2 potassium channels.to report a novel cell surface autoantigen of encephalitis that is a critical regulatory subunit of the kv4.2 potassium channels.201223225603
encephalitis and antibodies to dipeptidyl-peptidase-like protein-6, a subunit of kv4.2 potassium channels.to report a novel cell surface autoantigen of encephalitis that is a critical regulatory subunit of the kv4.2 potassium channels.201223225603
class iia bacteriocins: diversity and new developments.class iia bacteriocins are heat-stable, unmodified peptides with a conserved amino acids sequence ygngv on their n-terminal domains, and have received much attention due to their generally recognized as safe (gras) status, their high biological activity, and their excellent heat stability. they are promising and attractive agents that could function as biopreservatives in the food industry. this review summarizes the new developments in the area of class iia bacteriocins and aims to provide upto ...201223222636
experimental evidence validating the computational inference of functional associations from gene fusion events: a critical survey.more than a decade ago, a number of methods were proposed for the inference of protein interactions, using whole-genome information from gene clusters, gene fusions and phylogenetic profiles. this structural and evolutionary view of entire genomes has provided a valuable approach for the functional characterization of proteins, especially those without sequence similarity to proteins of known function. furthermore, this view has raised the real possibility to detect functional associations of ge ...201223220349
experimental evidence validating the computational inference of functional associations from gene fusion events: a critical survey.more than a decade ago, a number of methods were proposed for the inference of protein interactions, using whole-genome information from gene clusters, gene fusions and phylogenetic profiles. this structural and evolutionary view of entire genomes has provided a valuable approach for the functional characterization of proteins, especially those without sequence similarity to proteins of known function. furthermore, this view has raised the real possibility to detect functional associations of ge ...201223220349
isolation and characterization of microsatellite markers in the domestic ferret (mustela putorius furo).the domestic ferret (mustela putorius furo) is an important model organism for the study of avian influenza and other diseases of humans and animals, as well as a popular pet animal. in order to evaluate genetic diversity and study disease relationships in ferrets, 22 nuclear microsatellite loci (17 dinucleotide and 5 tetranucleotide) were developed from ferret genomic libraries and organized into seven multiplex sets. polymorphism was preliminarily assessed in one population in australia and on ...201223443120
active site comparisons and catalytic mechanisms of the hot dog superfamily. 201223205964
active site comparisons and catalytic mechanisms of the hot dog superfamily. 201223205964
specific synthesis of neurostatin and gangliosides o-acetylated in the outer sialic acids using a sialate transferase.gangliosides are sialic acid containing glycosphingolipids, commonly found on the outer leaflet of the plasma membrane. o-acetylation of sialic acid hydroxyl groups is one of the most common modifications in gangliosides. studies on the biological activity of o-acetylated gangliosides have been limited by their scarcity in nature. this comparatively small change in ganglioside structure causes major changes in their physiological properties. when the ganglioside gd1b was o-acetylated in the oute ...201223226505
description of a putative oligosaccharyl:s-layer protein transferase from the tyrosine o-glycosylation system of paenibacillus alvei ccm 2051(t).surface (s)-layer proteins are model systems for studying protein glycosylation in bacteria and simultaneously hold promises for the design of novel, glyco-functionalized modules for nanobiotechnology due to their 2d self-assembly capability. understanding the mechanism governing s-layer glycan biosynthesis in the gram-positive bacterium paenibacillus alvei ccm 2051(t) is necessary for the tailored glyco-functionalization of its s-layer. here, the putative oligosaccharyl:s-layer protein transfer ...201225893145
citrobacter infection and wnt signaling.gut flora generally contributes to a healthy environment while both commensal and pathogenic bacteria that influence the innate and adaptive immune responses, can cause acute and/or chronic mucosal inflammation. citrobacter rodentium (c. rodentium) is a member of the family of enteropathogens that provide an excellent in vivo model to investigate the host-pathogen interactions in real-time. it is the etiologic agent for transmissible murine colonic hyperplasia (tmch) while inflammation following ...201224358033
learning from bacteriophages - advantages and limitations of phage and phage-encoded protein applications.the emergence of bacteria resistance to most of the currently available antibiotics has become a critical therapeutic problem. the bacteria causing both hospital and community-acquired infections are most often multidrug resistant. in view of the alarming level of antibiotic resistance between bacterial species and difficulties with treatment, alternative or supportive antibacterial cure has to be developed. the presented review focuses on the major characteristics of bacteriophages and phage-en ...201223305359
miller fisher syndrome mimicking ocular myasthenia gravis.purpose.: miller fisher syndrome (mfs) is a rare immune-mediated neuropathy that commonly presents with diplopia after the acute onset of complete bilateral external ophthalmoplegia. ophthalmoplegia is often accompanied by other neurological deficits such as ataxia and areflexia that characterize mfs. although mfs is a clinical diagnosis, serological confirmation is possible by identifying the anti-gq1b antibody found in most of the affected patients. we report a patient with mfs who presented w ...201223190719
transcriptional regulation of the cmeabc multidrug efflux pump and the kata catalase by cosr in campylobacter jejuni.cosr is an essential response regulator in campylobacter jejuni, a major food-borne pathogen causing enteritis worldwide. a transcriptomic analysis performed in this study discovered 93 genes whose transcriptional levels were changed >2-fold due to the repression of cosr expression by antisense peptide nucleic acid. the identified cosr-regulated genes are involved in various cellular functions, such as energy production, protein synthesis and folding, flagellum biogenesis, and lipid metabolism. ...201223065977
genome sequence of moraxella catarrhalis rh4, an isolate of seroresistant lineage.here we report the annotated genome sequence of moraxella catarrhalis strain rh4, a seroresistant-lineage strain isolated from the blood of an infected patient. this genome sequence will allow us to gain further insight into the genetic diversity of clinical m. catarrhalis isolates and will facilitate study of m. catarrhalis pathogenesis.201223209224
enterococci in the environment.enterococci are common, commensal members of gut communities in mammals and birds, yet they are also opportunistic pathogens that cause millions of human and animal infections annually. because they are shed in human and animal feces, are readily culturable, and predict human health risks from exposure to polluted recreational waters, they are used as surrogates for waterborne pathogens and as fecal indicator bacteria (fib) in research and in water quality testing throughout the world. evidence ...201223204362
guillain-barré syndrome in two patients with respiratory failure and a review of the japanese literature.we described two patients with guillain-barré syndrome and respiratory failure with or without mechanical ventilation. case 1 was a 44-year-old man who treated as pneumonia under mechanical ventilation for a month and transferred to our hospital with unsuccessful weaning trials because of phrenic nerve palsy. case 2 was a 74-year-old man who presented with aspiration pneumonia because of bulbar palsy. the present two cases with review of the japanese literature showed that antecedent infection w ...201223205285
genotypic characterization of streptococcus infantarius subsp. coli isolates from sea otters with infective endocarditis and/or septicemia and from environmental mussel samples.pulsed-field gel electrophoresis (pfge) was used to type 128 streptococcus infantarius subsp. coli isolates from sea otters and mussels. six smai pfge groups were detected, with one predominant group representing 57% of the isolates collected over a wide geographic region. several sea otter and mussel isolates were highly related, suggesting that an environmental infection source is possible.201223052307
a single-cell genome for thiovulum sp.we determined a significant fraction of the genome sequence of a representative of thiovulum, the uncultivated genus of colorless sulfur epsilonproteobacteria, by analyzing the genome sequences of four individual cells collected from phototrophic mats from elkhorn slough, california. these cells were isolated utilizing a microfluidic laser-tweezing system, and their genomes were amplified by multiple-displacement amplification prior to sequencing. thiovulum is a gradient bacterium found at oxic- ...201223023751
campylobacter jejuni outer membrane vesicles play an important role in bacterial interactions with human intestinal epithelial cells.campylobacter jejuni is the most prevalent cause of food-borne gastroenteritis in the developed world; however, the molecular basis of pathogenesis is unclear. secretion of virulence factors is a key mechanism by which enteric bacterial pathogens interact with host cells to enhance survival and/or damage the host. however, c. jejuni lacks the virulence-associated secretion systems possessed by other enteric pathogens. many bacterial pathogens utilize outer membrane vesicles (omvs) for delivery o ...201222966047
thiol peroxidase is an important component of streptococcus pneumoniae in oxygenated environments.streptococcus pneumoniae is an aerotolerant gram-positive bacterium that causes an array of diseases, including pneumonia, otitis media, and meningitis. during aerobic growth, s. pneumoniae produces high levels of h(2)o(2). since s. pneumoniae lacks catalase, the question of how it controls h(2)o(2) levels is of critical importance. the psa locus encodes an abc mn(2+)-permease complex (psabca) and a putative thiol peroxidase, tpxd. this study shows that tpxd encodes a functional thiol peroxidase ...201223027531
synergistic action of gentamicin and bacteriophage in a continuous culture population of staphylococcus aureus.with the increasing frequency of antibiotic resistance and the decreasing frequency of new antibiotics entering the market, interest has returned to developing bacteriophage as a therapeutic agent. acceptance of phage therapy, however, is limited by the unknown pharmacodynamics of a replicating agent, as well as the potential for the evolution of resistant bacteria. one way to overcome some of these limitations is to incorporate phage and antibiotics into a dual therapy regimen; however, this in ...201223226451
contribution of amino acid catabolism to the tissue specific persistence of campylobacter jejuni in a murine colonization model.campylobacter jejuni is a major cause of food-borne disease in industrialized countries. carbohydrate utilization by c. jejuni is severely restricted, and knowledge about which substrates fuel c. jejuni infection and growth is limited. some amino acids have been shown to serve as carbon sources both in vitro and in vivo. in the present study we investigated the contribution of serine and proline catabolism to the invitro and invivo growth of c. jejuni 81-176. we confirmed that the serine transpo ...201223226358
sinorhizobium meliloti sigma factors rpoe1 and rpoe4 are activated in stationary phase in response to sulfite.rhizobia are soil bacteria able to establish a nitrogen-fixing symbiosis with legume plants. both in soil and in planta, rhizobia spend non-growing periods resembling the stationary phase of in vitro-cultured bacteria. the primary objective of this work was to better characterize gene regulation in this biologically relevant growth stage in sinorhizobium meliloti. by a tap-tag/mass spectrometry approach, we identified five sigma factors co-purifying with the rna polymerase in stationary phase: t ...201223226379
norovirus gastroenteritis in immunocompromised patients. 201223190223
gold nanoparticles-coated su-8 for sensitive fluorescence-based detections of dna.su-8 epoxy-based negative photoresist has been extensively employed as a structural material for fabrication of numerous biological microelectro-mechanical systems (bio-mems) or lab-on-a-chip (loc) devices. however, su-8 has a high autofluorescence level that limits sensitivity of microdevices that use fluorescence as the predominant detection workhorse. here, we show that deposition of a thin gold nanoparticles layer onto the su-8 surface significantly reduces the autofluorescence of the coated ...201226859400
microbial pathways in colonic sulfur metabolism and links with health and disease.sulfur is both crucial to life and a potential threat to health. while colonic sulfur metabolism mediated by eukaryotic cells is relatively well studied, much less is known about sulfur metabolism within gastrointestinal microbes. sulfated compounds in the colon are either of inorganic (e.g., sulfates, sulfites) or organic (e.g., dietary amino acids and host mucins) origin. the most extensively studied of the microbes involved in colonic sulfur metabolism are the sulfate-reducing bacteria (srb), ...201223226130
phylogenetic identification of bacterial mazf toxin protein motifs among probiotic strains and foodborne pathogens and potential implications of engineered probiotic intervention in food. 201223186337
a single n-acetylgalactosamine residue at threonine 106 modifies the dynamics and structure of interferon α2a around the glycosylation site.enzymatic addition of galnac to isotopically labeled ifnα2a produced in escherichia coli yielded the o-linked glycoprotein galnacα-[(13)c,(15)n]ifnα2a. the three-dimensional structure of galnacα-ifnα2a has been determined in solution by nmr spectroscopy at high resolution. proton-nitrogen heteronuclear overhauser enhancement measurements revealed that the addition of a single monosaccharide unit at thr-106 significantly slowed motions of the glycosylation loop on the nanosecond time scale. subse ...201223184955
a single n-acetylgalactosamine residue at threonine 106 modifies the dynamics and structure of interferon α2a around the glycosylation site.enzymatic addition of galnac to isotopically labeled ifnα2a produced in escherichia coli yielded the o-linked glycoprotein galnacα-[(13)c,(15)n]ifnα2a. the three-dimensional structure of galnacα-ifnα2a has been determined in solution by nmr spectroscopy at high resolution. proton-nitrogen heteronuclear overhauser enhancement measurements revealed that the addition of a single monosaccharide unit at thr-106 significantly slowed motions of the glycosylation loop on the nanosecond time scale. subse ...201223184955
phosphatidylinositol 3-kinase-γ signaling promotes campylobacter jejuni-induced colitis through neutrophil recruitment in mice.crypt abscesses caused by excessive neutrophil accumulation are prominent features of human campylobacteriosis and its associated pathology. the molecular and cellular events responsible for this pathological situation are currently unknown. we investigated the contribution of pi3k-γ signaling in campylobacter jejuni-induced neutrophil accumulation and intestinal inflammation. germ-free and specific pathogen-free il10(-/-) and germ-free il10(-/-);rag2(-/-) mice were infected with c. jejuni (10(9 ...201223180818
phosphatidylinositol 3-kinase-γ signaling promotes campylobacter jejuni-induced colitis through neutrophil recruitment in mice.crypt abscesses caused by excessive neutrophil accumulation are prominent features of human campylobacteriosis and its associated pathology. the molecular and cellular events responsible for this pathological situation are currently unknown. we investigated the contribution of pi3k-γ signaling in campylobacter jejuni-induced neutrophil accumulation and intestinal inflammation. germ-free and specific pathogen-free il10(-/-) and germ-free il10(-/-);rag2(-/-) mice were infected with c. jejuni (10(9 ...201223180818
multidrug efflux systems in helicobacter cinaedi.helicobacter cinaedi causes infections, such as bacteremia, diarrhea and cellulitis in mainly immunocompromised patients. this pathogen is often problematic to analyze, and insufficient information is available, because it grows slowly and poorly in subculture under a microaerobic atmosphere. the first-choice therapy to eradicate h. cinaedi is antimicrobial chemotherapy; however, its use is linked to the development of resistance. although we need to understand the antimicrobial resistance mecha ...201227029418
an unusual case of parinaud's syndrome.a 25-year-old man presented with blurred vision, headache and dizziness. on questioning, there was also a history of a preceding diarrhoeal illness. initial investigations were normal. however, after a week, he represented with a parinaud's syndrome. in view of the preceding diarrhoea, the transient unsteadiness and the areflexia on examination, anti-gq1b antibodies were requested. the resulting titre was positive confirming the suspected diagnosis of miller fisher syndrome. he responded to intr ...201223175005
graphalignment: bayesian pairwise alignment of biological networks.with increased experimental availability and accuracy of bio-molecular networks, tools for their comparative and evolutionary analysis are needed. a key component for such studies is the alignment of networks.201223171476
crystal structures of the helicobacter pylori mtan enzyme reveal specific interactions between s-adenosylhomocysteine and the 5'-alkylthio binding subsite.the bacterial 5'-methylthioadenosine/s-adenosylhomocysteine nucleosidase (mtan) enzyme is a multifunctional enzyme that catalyzes the hydrolysis of the n-ribosidic bond of at least four different adenosine-based metabolites: s-adenosylhomocysteine (sah), 5'-methylthioadenosine (mta), 5'-deoxyadenosine (5'-doa), and 6-amino-6-deoxyfutalosine. these activities place the enzyme at the hub of seven fundamental bacterial metabolic pathways: s-adenosylmethionine (sam) utilization, polyamine biosynthes ...201223148563
effects of the campylobacter jejuni cjie1 prophage homologs on adherence and invasion in culture, patient symptoms, and source of infection.prophages of enteric bacteria are frequently of key importance for the biology, virulence, or host adaptation of their host. some c. jejuni isolates carry homologs of the cjie1 (cmlp 1) prophage that carry cargo genes potentially involved in virulence. possible role(s) of cjie1 homologs in the biology and virulence of c. jejuni were therefore investigated by using in vitro cell culture assays and by assessing the association of c. jejuni isolates with and without these prophages with patients' s ...201223167543
the evolution of mutualism in gut microbiota via host epithelial selection.the human gut harbours a large and genetically diverse population of symbiotic microbes that both feed and protect the host. evolutionary theory, however, predicts that such genetic diversity can destabilise mutualistic partnerships. how then can the mutualism of the human microbiota be explained? here we develop an individual-based model of host-associated microbial communities. we first demonstrate the fundamental problem faced by a host: the presence of a genetically diverse microbiota leads ...201223185130
health-promoting properties of lactobacillus helveticus.lactobacillus helveticus is an important industrial thermophilic starter that is predominantly employed in the fermentation of milk for the manufacture of several cheeses. in addition to its technological importance, a growing body of scientific evidence shows that strains belonging to the l. helveticus species have health-promoting properties. in this review, we synthesize the results of numerous primary literature papers concerning the ability of l. helveticus strains to positively influence h ...201223181058
identification of an atypical zinc metalloproteinase, zmpc, from an epidemic conjunctivitis-causing strain of streptococcus pneumoniae.streptococcus pneumoniae is a pathogen associated with a range of invasive and noninvasive infections. despite the identification of the majority of virulence factors expressed by s. pneumoniae, knowledge of the strategies used by this bacterium to trigger infections, especially those originating at wet-surfaced epithelia, remains limited. in this regard, we recently reported a mechanism used by a nonencapsulated, epidemic conjunctivitis-causing strain of s. pneumoniae (strain sp168) to gain acc ...201223168398
identification of an atypical zinc metalloproteinase, zmpc, from an epidemic conjunctivitis-causing strain of streptococcus pneumoniae.streptococcus pneumoniae is a pathogen associated with a range of invasive and noninvasive infections. despite the identification of the majority of virulence factors expressed by s. pneumoniae, knowledge of the strategies used by this bacterium to trigger infections, especially those originating at wet-surfaced epithelia, remains limited. in this regard, we recently reported a mechanism used by a nonencapsulated, epidemic conjunctivitis-causing strain of s. pneumoniae (strain sp168) to gain acc ...201223168398
metabolic adaptation and protein complexes in prokaryotes.protein complexes are classified and have been charted in several large-scale screening studies in prokaryotes. these complexes are organized in a factory-like fashion to optimize protein production and metabolism. central components are conserved between different prokaryotes; major complexes involve carbohydrate, amino acid, fatty acid and nucleotide metabolism. metabolic adaptation changes protein complexes according to environmental conditions. protein modification depends on specific modify ...201224957769
capillary electrophoresis with three-color fluorescence detection for the analysis of glycosphingolipid metabolism.a capillary electrophoresis system with an ultrasensitive three-color laser-induced fluorescence detector was constructed for the simultaneous measurement of glycosphingolipids conjugated with a family of bodipy fluorophores. the compounds were separated by capillary electrophoresis and detected by laser-induced fluorescence excited within a sheath-flow cuvette. diode-pumped solid-state lasers operating at 473 nm and 532 nm, and a diode laser operating at 633 nm were used to excite glycosphingol ...201223154386
capillary electrophoresis with three-color fluorescence detection for the analysis of glycosphingolipid metabolism.a capillary electrophoresis system with an ultrasensitive three-color laser-induced fluorescence detector was constructed for the simultaneous measurement of glycosphingolipids conjugated with a family of bodipy fluorophores. the compounds were separated by capillary electrophoresis and detected by laser-induced fluorescence excited within a sheath-flow cuvette. diode-pumped solid-state lasers operating at 473 nm and 532 nm, and a diode laser operating at 633 nm were used to excite glycosphingol ...201223154386
interactions between parasites and microbial communities in the human gut.the interactions between intestinal microbiota, immune system, and pathogens describe the human gut as a complex ecosystem, where all components play a relevant role in modulating each other and in the maintenance of homeostasis. the balance among the gut microbiota and the human body appear to be crucial for health maintenance. intestinal parasites, both protozoans and helminths, interact with the microbial community modifying the balance between host and commensal microbiota. on the other hand ...201223162802
two unusual variants of guillain-barre syndrome.guillain-barre syndrome (gbs) is a group of autoimmune diseases characterised by acute, acquired and immune-mediated polyneuroradiculopathy. a large number of clinical subtypes of gbs have been described over last 100 years since the first description of this syndrome. we report two such cases gbs variants--first, aman with brisk reflexes and second being acute motor axonal neuropathy with conduction block. through this case report, we intend to make the treating physicians and neurologist aware ...201223162026
molecular-based detection of the gastrointestinal pathogen campylobacter ureolyticus in unpasteurized milk samples from two cattle farms in ireland.campylobacter jejuni and coli are collectively regarded as the most prevalent cause of bacterial foodborne illness worldwide. an emerging species, campylobacter ureolyticus has recently been detected in patients with gastroenteritis, however, the source of this organism has, until now, remained unclear. herein, we describe the molecular-based detection of this pathogen in bovine faeces (1/20) and unpasteurized milk (6/47) but not in poultry (chicken wings and caeca). this is, to the best of our ...201223151337
celiac disease: prevalence, diagnosis, pathogenesis and treatment.celiac disease (cd) is one of the most common diseases, resulting from both environmental (gluten) and genetic factors [human leukocyte antigen (hla) and non-hla genes]. the prevalence of cd has been estimated to approximate 0.5%-1% in different parts of the world. however, the population with diabetes, autoimmune disorder or relatives of cd individuals have even higher risk for the development of cd, at least in part, because of shared hla typing. gliadin gains access to the basal surface of th ...201223155333
respiratory proteins contribute differentially to campylobacter jejuni's survival and in vitro interaction with hosts' intestinal cells.the genetic features that facilitate campylobacter jejuni's adaptation to a wide range of environments are not completely defined. however, whole genome expression studies showed that respiratory proteins (rps) were differentially expressed under varying conditions and stresses, suggesting further unidentified roles for rps in c. jejuni's adaptation. therefore, our objectives were to characterize the contributions of selected rps to c. jejuni's i- key survival phenotypes under different temperat ...201223148765
participation of the cytoskeletal and lysosomal compartments in campylobacter jejuni invasion of caco-2 cells, the cellular response by morphometric analysis and the presence of cytokine and chemokine transcripts.this study aimed to evaluate the participation of actin and tubulin in the process of internalisation, the interaction of bacterial phagosomes with lysosomes, the morphometric changes and the expression of inflammatory cytokines in caco-2 cells infected with campylobacter jejuni. both actin and tubulin participated in the process of internalisation. inside the cells, lysosomes fuse with phagosomes, which may lead to bacterial death because after 2 h, the bacteria were not detected by transmissio ...201224426102
participation of the cytoskeletal and lysosomal compartments in campylobacter jejuni invasion of caco-2 cells, the cellular response by morphometric analysis and the presence of cytokine and chemokine transcripts.this study aimed to evaluate the participation of actin and tubulin in the process of internalisation, the interaction of bacterial phagosomes with lysosomes, the morphometric changes and the expression of inflammatory cytokines in caco-2 cells infected with campylobacter jejuni. both actin and tubulin participated in the process of internalisation. inside the cells, lysosomes fuse with phagosomes, which may lead to bacterial death because after 2 h, the bacteria were not detected by transmissio ...201224426102
in vitro antibacterial and time-kill evaluation of the erythrina caffra thunb. extract against bacteria associated with diarrhoea.the antibacterial activities of stem bark ethanolic extract of erythrina caffra thunb. against bacteria in diarrhoea was determined in vitro by the agar diffusion and dilution, macrobroth dilution, and time-kill assay methods. the result showed that the extract produced inhibition zones ranging between 15 ± 1.0 mm and 23 ± 1.0 mm, and the bacteria were susceptible at concentrations ranging between ≤100 and ≤1000 μg/ml. while the mics of the extract ranged between 39.1 and 625 μg/ml, and the mbcs ...201223213297
mucin biopolymers prevent bacterial aggregation by retaining cells in the free-swimming state.many species of bacteria form surface-attached communities known as biofilms. surrounded in secreted polymers, these aggregates are difficult both to prevent and eradicate, posing problems for medicine and industry. humans play host to hundreds of trillions of microbes that live adjacent to our epithelia, and we are typically able to prevent harmful colonization. mucus, the hydrogel overlying all wet epithelia in the body, can prevent bacterial contact with the underlying tissue. the digestive t ...201223142047
molecular evidence for the thriving of campylobacter jejuni st-4526 in japan.campylobacter jejuni is a leading cause of human gastroenteritis worldwide. this study aimed at a better understanding of the genetic diversity of this pathogen disseminated in japan. we performed multilocus sequence typing (mlst) of campylobacter jejuni isolated from different sources (100 human, 61 poultry, and 51 cattle isolates) in japan between 2005 and 2006. this approach identified 62 sequence types (sts) and 19 clonal complexes (ccs), including 11 novel sts. these 62 sts were phylogeneti ...201223144873
guillain-barré syndrome associated with primary parvovirus b19 infection in an hiv-1-infected patient.parvovirus b19 (b19v) infection has rarely been reported as responsible for guillain-barré syndrome (gbs). we present the case of a 63-year-old man with aids who presented with rapidly progressing weakness of his inferior limbs and a newly appeared pancytopenia. csf examination and electromyography were characteristic for gbs. very high csf and serum b19v dna concentrations were present, in the absence of igg or igm against b19v. the neurologic and hematologic abnormalities improved after a 5-da ...201223251163
chronic exposure to the cytolethal distending toxins of gram-negative bacteria promotes genomic instability and altered dna damage response.epidemiological evidence links chronic bacterial infections to the increased incidence of certain types of cancer but the molecular mechanisms by which bacteria contribute to tumour initiation and progression are still poorly characterized. here we show that chronic exposure to the genotoxin cytolethal distending toxin (cdt) of gram-negative bacteria promotes genomic instability and acquisition of phenotypic properties of malignancy in fibroblasts and colon epithelial cells. cells grown for more ...201222998585
chronic exposure to the cytolethal distending toxins of gram-negative bacteria promotes genomic instability and altered dna damage response.epidemiological evidence links chronic bacterial infections to the increased incidence of certain types of cancer but the molecular mechanisms by which bacteria contribute to tumour initiation and progression are still poorly characterized. here we show that chronic exposure to the genotoxin cytolethal distending toxin (cdt) of gram-negative bacteria promotes genomic instability and acquisition of phenotypic properties of malignancy in fibroblasts and colon epithelial cells. cells grown for more ...201222998585
pulmonary streptomyces infection in patient with sarcoidosis, france, 2012.to the editor: streptomyces spp. are aerobic, gram-positive bacteria of the order actinomycetales, known for their ability to produce antimicrobial molecules such as streptomycin. streptomyces spp., usually saprophytic to humans, can cause local cutaneous fistulized nodules known as actinomycetoma or mycetoma. severe invasive infections have seldom been reported, but most cases reported have occurred in immunocompromised patients (1-5). we report a case of invasive pulmonary infection caused by ...201223092549
hyperosmotic stress response of campylobacter jejuni.the diarrheal pathogen campylobacter jejuni and other gastrointestinal bacteria encounter changes in osmolarity in the environment, through exposure to food processing, and upon entering host organisms, where osmotic adaptation can be associated with virulence. in this study, growth profiles, transcriptomics, and phenotypic, mutant, and single-cell analyses were used to explore the effects of hyperosmotic stress exposure on c. jejuni. increased growth inhibition correlated with increased osmotic ...201222961853
a novel component of the rhodobacter sphaeroides fla1 flagellum is essential for motor rotation.here we describe a novel component essential for flagellar rotation in rhodobacter sphaeroides. this protein is encoded by motf (rsp_0067), the first gene of a predicted transcriptional unit which contains two hypothetical genes. sequence analysis indicated that motf is a bitopic membrane-spanning protein. protease sensitivity assays and green fluorescent protein (gfp) fusions confirmed this prediction and allowed us to conclude that the c terminus of motf is located in the periplasmic space. wi ...201222961858
complete genome sequence of a variant of campylobacter jejuni nctc 11168.campylobacter jejuni nctc 11168 is widely used in research, but at least two variants have been reported. the available genome was sequenced from a variant which later showed a different phenotype and gene expression profile. here we present the complete genome sequence of a second variant of c. jejuni nctc 11168.201223105049
microbiological applications of high-resolution melting analysis.high-resolution melting (hrm) analysis uses real-time pcr instrumentation to interrogate dna sequence variation and is a low-cost, single-step, closed-tube method. here we describe hrm technology and provide examples of varied clinical microbiological applications to highlight the strengths and limitations of hrm analysis.201222875887
the yfe and feo transporters are involved in microaerobic growth and virulence of yersinia pestis in bubonic plague.the yfe/sit and feo transport systems are important for the growth of a variety of bacteria. in yersinia pestis, single mutations in either yfe or feo result in reduced growth under static (limited aeration), iron-chelated conditions, while a yfe feo double mutant has a more severe growth defect. these growth defects were not observed when bacteria were grown under aerobic conditions or in strains capable of producing the siderophore yersiniabactin (ybt) and the putative ferrous transporter fetm ...201222927049
the challenge of regulating agricultural ceftiofur use to slow the emergence of resistance to extended-spectrum cephalosporins. 201222961892
high prevalence and species diversity of helicobacter spp. detected in wild house mice.pcr diagnostics detected 100% prevalence of helicobacter in 425 wild house mice (mus musculus) from across central europe. of seven species identified, the five most frequent were helicobacter rodentium (78%), h. typhlonius (53%), h. hepaticus (41%), h. bilis (30%), and h. muridarum (1%). double infections were more common (42%) than single (30%) and triple (21%) infections. wild house mice could be considered potential reservoirs of helicobacter strains for both humans and other vertebrates.201222961895
survival and germination of bacillus cereus spores without outgrowth or enterotoxin production during in vitro simulation of gastrointestinal transit.to study the gastrointestinal survival and enterotoxin production of the food-borne pathogen bacillus cereus, an in vitro simulation experiment was developed to mimic gastrointestinal passage in 5 phases: (i) the mouth, (ii) the stomach, with gradual ph decrease and fractional emptying, (iii) the duodenum, with high concentrations of bile and digestive enzymes, (iv) dialysis to ensure bile reabsorption, and (v) the ileum, with competing human intestinal bacteria. four different b. cereus strains ...201222923409
differences in the fecal concentrations and genetic diversities of campylobacter jejuni populations among individual cows in two dairy herds.dairy cows have been identified as common carriers of campylobacter jejuni, which causes many of the human gastroenteritis cases reported worldwide. to design on-farm management practices that control the human infection sourced from dairy cows, the first step is to acquire an understanding of the excretion patterns of the cow reservoir. we monitored the same 35 cows from two dairy farms for c. jejuni excretion fortnightly for up to 12 months. the objective was to examine the concentration of c. ...201222904055
identification of essential genes of the periodontal pathogen porphyromonas gingivalis.porphyromonas gingivalis is a gram-negative anaerobic bacterium associated with periodontal disease onset and progression. genetic tools for the manipulation of bacterial genomes allow for in-depth mechanistic studies of metabolism, physiology, interspecies and host-pathogen interactions. analysis of the essential genes, protein-coding sequences necessary for survival of p. gingivalis by transposon mutagenesis has not previously been attempted due to the limitations of available transposon syste ...201223114059
functional glycomic analysis of human milk glycans reveals the presence of virus receptors and embryonic stem cell biomarkers.human milk contains a large diversity of free glycans beyond lactose, but their functions are not well understood. to explore their functional recognition, here we describe a shotgun glycan microarray prepared from isolated human milk glycans (hmgs), and our studies on their recognition by viruses, antibodies, and glycan-binding proteins (gbps), including lectins. the total neutral and sialylated hmgs were derivatized with a bifunctional fluorescent tag, separated by multidimensional hplc, and a ...201223115247
a unique host defense pathway: trif mediates both antiviral and antibacterial immune responses.both anti-viral and anti-bacterial host defense mechanisms involve trif signaling. trif provides early clearance of pathogens and coordination of a local inflammatory ensemble through an interferon cascade, while it may trigger organ damage. the multipotentiality of trif-mediated immune machinery may direct the fate of our continuous battle with microbes.201223116944
a unique host defense pathway: trif mediates both antiviral and antibacterial immune responses.both anti-viral and anti-bacterial host defense mechanisms involve trif signaling. trif provides early clearance of pathogens and coordination of a local inflammatory ensemble through an interferon cascade, while it may trigger organ damage. the multipotentiality of trif-mediated immune machinery may direct the fate of our continuous battle with microbes.201223116944
different imaging findings of inflammatory myofibroblastic tumor of the liver.inflammatory myofibroblastic tumor (imt) in the liver is an uncommon lesion of uncertain pathogenesis. in most cases, symptomatological imaging and clinical studies suggest malignancy. we report a case of liver imt with imaging findings from positron emission tomography/computed tomography (pet/ct), contrast-enhanced computed tomography (cect) and contrast-enhanced ultrasonography (ceus). this report was the first to depict a pet/ct scan of a liver imt that revealed an inhomogeneous, intense (fl ...201223155327
treatment of diarrhoea in rural african communities: an overview of measures to maximise the medicinal potentials of indigenous plants.diarrhoea is a major cause of morbidity and mortality in rural communities in africa, particularly in children under the age of five. this calls for the development of cost effective alternative strategies such as the use of herbal drugs in the treatment of diarrhoea in these communities. expenses associated with the use of orthodox medicines have generated renewed interest and reliance on indigenous medicinal plants in the treatment and management of diarrhoeal infections in rural communities. ...201223202823
receptor-like molecules on human intestinal epithelial cells interact with an adhesion factor from lactobacillus reuteri.a surface protein of lactobacillus reuteri, mucus adhesion-promoting protein (mapa), is considered to be an adhesion factor. mapa is expressed in l. reuteri strains and adheres to piglet gastric mucus, collagen type i, and human intestinal epithelial cells such as caco-2. the aim of this study was to identify molecules that mediate the attachment of mapa from l. reuteri to the intestinal epithelial cell surface by investigating the adhesion of mapa to receptor-like molecules on caco-2 cells. map ...201224936355
characterization and structure of the aquifex aeolicus protein duf752: a bacterial trna-methyltransferase (mnmc2) functioning without the usually fused oxidase domain (mnmc1).post-transcriptional modifications of the wobble uridine (u34) of trnas play a critical role in reading nna/g codons belonging to split codon boxes. in a subset of escherichia coli trna, this wobble uridine is modified to 5-methylaminomethyluridine (mnm(5)u34) through sequential enzymatic reactions. uridine 34 is first converted to 5-carboxymethylaminomethyluridine (cmnm(5)u34) by the mnme-mnmg enzyme complex. the cmnm(5)u34 is further modified to mnm(5)u by the bifunctional mnmc protein. in the ...201223091054
a new generation microarray for the simultaneous detection and identification of yersinia pestis and bacillus anthracis in food.the use of microarrays as a multiple analytic system has generated increased interest and provided a powerful analytical tool for the simultaneous detection of pathogens in a single experiment. a wide array of applications for this technology has been reported. a low density oligonucleotide microarray was generated from the genetic sequences of y. pestis and b. anthracis and used to fabricate a microarray chip. the new generation chip, consisting of 2,240 spots in 4 quadrants with the capability ...201223125935
redundancy and modularity in membrane-associated dissimilatory nitrate reduction in bacillus.the genomes of two phenotypically denitrifying type strains of the genus bacillus were sequenced and the pathways for dissimilatory nitrate reduction were reconstructed. results suggest that denitrification proceeds in the periplasmic space and in an analogous fashion as in gram-negative organisms, yet with the participation of proteins that tend to be membrane-bound or membrane-associated. a considerable degree of functional redundancy was observed with marked differences between b. azotoforman ...201223087684
a case of helicobacter cinaedi bacteremia in an asplenic patient.helicobacter cinaedi is an enterohepatic species. it can cause bacteremia, gastroenteritis, and cellulitis, particularly in immunocompromised individuals, such as those with acquired immunodeficiency syndrome, malignancy, or alcoholism. there are no previous reports of h. cinaedi infection in korea. a 71-yr-old man was admitted to the emergency room because of dyspnea on november 9, 2011. he had undergone splenectomy 3 yr ago because of immune hemolytic anemia. chest plain radiography revealed b ...201223130344
crystal structure of the campylobacter jejuni cj0090 protein reveals a novel variant of the immunoglobulin fold among bacterial lipoproteins.bacterial lipoproteins play an important role in bacterial pathogenesis and physiology. the genome of campylobacter jejuni, a major foodborn pathogen, is predicted to contain over 20 lipoproteins. however, the functions of the majority of c. jejuni lipoproteins remain unknown. the cj0090 protein is encoded by a lipoprotein operon composed of cj0089, cj0090, and cj0091. here, we report the crystal structure of cj0090 at 1.9 å resolution, revealing a novel variant of the immunoglobulin fold with β ...201222987763
hemolytic uremic syndrome and clostridium difficile colitis.hemolytic uremic syndrome (hus) can be associated with different infectious etiologies, but the relationship between pseudomembranous colitis and hus was first described in the 1970s in some childhood patients. there is very limited published literature on clostridium difficile-associated hus. we report a case of c. difficile-related hus in an adult patient and provide a review of the literature.201223882375
the kizss network, a sentinel surveillance system for infectious diseases in day care centers: study protocol.day care-associated infectious diseases are widely recognized as a public health problem but rarely studied. insights into their dynamics and their association with the day care setting are important for effective decision making in management of infectious disease control. this paper describes the purpose, design and potential of our national multi-center, day care-based sentinel surveillance network for infectious diseases (the kizss network). the aim of the kizss network is to acquire a long- ...201223066727
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