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signaling mechanisms for activation of extracytoplasmic function (ecf) sigma factors.a variety of mechanisms are used to signal extracytoplasmic conditions to the cytoplasm. these mechanisms activate extracytoplasmic function (ecf) sigma factors which recruit rna-polymerase to specific genes in order to express appropriate proteins in response to the changing environment. the two best understood ecf signaling pathways regulate sigma(e)-mediated expression of periplasmic stress response genes in escherichia coli and feci-mediated expression of iron-citrate transport genes in e. c ...200817673165
application of intact cell-based nfat-beta-lactamase reporter assay for pasteurella multocida toxin-mediated activation of calcium signaling pathway.pasteurella multocida toxin (pmt) stimulates and subsequently uncouples phospholipase c beta1 (plcbeta1) signal transduction through its selective action on the alpha subunit of the gq-protein. here, we describe the application of an nfat-beta-lactamase reporter assay as a functional readout for pmt-induced activation of the gq-protein-coupled plcbeta1-ip(3)-ca(2+) signaling pathway. use of the nfat-beta-lactamase reporter assay with a cell-permeable fluorogenic substrate provides high sensitivi ...200818190943
application of intact cell-based nfat-beta-lactamase reporter assay for pasteurella multocida toxin-mediated activation of calcium signaling pathway.pasteurella multocida toxin (pmt) stimulates and subsequently uncouples phospholipase c beta1 (plcbeta1) signal transduction through its selective action on the alpha subunit of the gq-protein. here, we describe the application of an nfat-beta-lactamase reporter assay as a functional readout for pmt-induced activation of the gq-protein-coupled plcbeta1-ip(3)-ca(2+) signaling pathway. use of the nfat-beta-lactamase reporter assay with a cell-permeable fluorogenic substrate provides high sensitivi ...200818190943
structural biology of membrane-intrinsic beta-barrel enzymes: sentinels of the bacterial outer membrane.the outer membranes of gram-negative bacteria are replete with integral membrane proteins that exhibit antiparallel beta-barrel structures, but very few of these proteins function as enzymes. in escherichia coli, only three beta-barrel enzymes are known to exist in the outer membrane; these are the phospholipase ompla, the protease ompt, and the phospholipidcolon, two colonslipid a palmitoyltransferase pagp, all of which have been characterized at the structural level. structural details have al ...200817880914
structural biology of membrane-intrinsic beta-barrel enzymes: sentinels of the bacterial outer membrane.the outer membranes of gram-negative bacteria are replete with integral membrane proteins that exhibit antiparallel beta-barrel structures, but very few of these proteins function as enzymes. in escherichia coli, only three beta-barrel enzymes are known to exist in the outer membrane; these are the phospholipase ompla, the protease ompt, and the phospholipidcolon, two colonslipid a palmitoyltransferase pagp, all of which have been characterized at the structural level. structural details have al ...200817880914
comparative genomics and an insect model rapidly identify novel virulence genes of burkholderia mallei.burkholderia pseudomallei and its host-adapted deletion clone burkholderia mallei cause the potentially fatal human diseases melioidosis and glanders, respectively. the antibiotic resistance profile and ability to infect via aerosol of these organisms and the absence of protective vaccines have led to their classification as major biothreats and select agents. although documented infections by these bacteria date back over 100 years, relatively little is known about their virulence and pathogeni ...200818223084
active-site mobility revealed by the crystal structure of arylmalonate decarboxylase from bordetella bronchiseptica.arylmalonate decarboxylase (amdase) from bordetella bronchiseptica catalyzes the enantioselective decarboxylation of arylmethylmalonates without the need for an organic cofactor or metal ion. the decarboxylation reaction is of interest for the synthesis of fine chemicals. as basis for an analysis of the catalytic mechanism of amdase and for a rational enzyme design, we determined the x-ray structure of the enzyme up to 1.9 a resolution. like the distantly related aspartate or glutamate racemases ...200818258259
persistent bordetella bronchiseptica pneumonia in an immunocompetent infant and genetic comparison of clinical isolates with kennel cough vaccine strains.an infant who experienced recurrent episodes of respiratory failure received a diagnosis of pertussis on the basis of immunofluorescence testing, but culture revealed macrolide-resistant bordetella bronchiseptica. genetic analysis demonstrated that the child was not infected with a kennel cough vaccine strain, although the family's dog had recently been vaccinated. the infection cleared with imipenem therapy.200818260750
utilization of lactoferrin-bound and transferrin-bound iron by campylobacter jejuni.campylobacter jejuni nctc 11168 was capable of growth to levels comparable with feso4 in defined iron-limited medium (minimal essential medium alpha [memalpha]) containing ferrilactoferrin, ferritransferrin, or ferri-ovotransferrin. iron was internalized in a contact-dependent manner, with 94% of cell-associated radioactivity from either 55fe-loaded transferrin or lactoferrin associated with the soluble cell fraction. partitioning the iron source away from bacteria significantly decreased cellul ...200818203832
pulmonary bacterial pathogens in cystic fibrosis patients and antibiotic therapy: a tool for the health workers.cystic fibrosis is the most common and best known genetic disease involving a defect in transepithelial cl- transport by mutations in the cf gene on chromosome 7, which codes for the cystic fibrosis transmembrane conductance regulator protein (cftr). the most serious symptoms are observed in the lungs, augmenting the risk of bacterial infection. the objective of this review was to describe the bacterial pathogens colonizing patients with cystic fibrosis. a systematic search was conducted using t ...200818992146
assessment of gut bacteria for a paratransgenic approach to control dermolepida albohirtum larvae.bacteria from the hindguts of dermolepida albohirtum larvae were assessed for their potential to be used in paratransgenic strategies that target scarab pests of sugarcane. bacteria isolated in pure culture from the hindguts of d. albohirtum larvae were from the proteobacteria, firmicutes, and actinobacteria phyla and matched closely with taxa from intestinal and rhizosphere environments. however, these isolates were not the most common gut-associated bacteria identified in denaturing gradient g ...200818456847
molecular genetic basis of ribotyping.nearly 2,000 ribotyping-based studies exist, ranging from epidemiology to phylogeny and taxonomy. none precisely reveals the molecular genetic basis, with many incorrectly attributing detected polymorphisms to rrna gene sequences. based on in silico genomics, we demonstrate that ribotype polymorphisms result from sequence variability in neutral housekeeping genes flanking rrna operons, with rrna gene sequences serving solely as conserved, flank-linked tags. we also reveal that from such an infor ...200818400796
genome-wide survey of prokaryotic serine proteases: analysis of distribution and domain architectures of five serine protease families in prokaryotes.serine proteases are one of the most abundant groups of proteolytic enzymes found in all the kingdoms of life. while studies have established significant roles for many prokaryotic serine proteases in several physiological processes, such as those associated with metabolism, cell signalling, defense response and development, functional associations for a large number of prokaryotic serine proteases are relatively unknown. current analysis is aimed at understanding the distribution and probable b ...200819019219
estimating the fraction of non-coding rnas in mammalian transcriptomes.recent studies of mammalian transcriptomes have identified numerous rna transcripts that do not code for proteins; their identity, however, is largely unknown. here we explore an approach based on sequence randomness patterns to discern different rna classes. the relative z-score we use helps identify the known ncrna class from the genome, intergene and intron classes. this leads us to a fractional ncrna measure of putative ncrna datasets which we model as a mixture of genuine ncrnas and other t ...200819812767
systematic identification of stem-loop containing sequence families in bacterial genomes.analysis of non-coding sequences in several bacterial genomes brought to the identification of families of repeated sequences, able to fold as secondary structures. these sequences have often been claimed to be transcribed and fulfill a functional role. a previous systematic analysis of a representative set of 40 bacterial genomes produced a large collection of sequences, potentially able to fold as stem-loop structures (sls). computational analysis of these sequences was carried out by searchin ...200818201379
white tide. 200825949289
white tide. 200825949289
neutrophil recruitment to the lungs during bacterial pneumonia. 200819015252
neutrophil recruitment to the lungs during bacterial pneumonia. 200819015252
boolean network simulations for life scientists.modern life sciences research increasingly relies on computational solutions, from large scale data analyses to theoretical modeling. within the theoretical models boolean networks occupy an increasing role as they are eminently suited at mapping biological observations and hypotheses into a mathematical formalism. the conceptual underpinnings of boolean modeling are very accessible even without a background in quantitative sciences, yet it allows life scientists to describe and explore a wide r ...200819014577
detection of mycoplasma hyopneumoniae by polymerase chain reaction in swine presenting respiratory problems.since mycoplasma hyopneumoniae isolation in appropriate media is a difficult task and impractical for daily routine diagnostics, nested-pcr (n-pcr) techniques are currently used to improve the direct diagnostic sensitivity of swine enzootic pneumonia. in a first experiment, this paper describes a n-pcr technique optimization based on three variables: different sampling sites, sample transport media, and dna extraction methods, using eight pigs. based on the optimization results, a second experim ...200824031248
a new pheromone trail-based genetic algorithm for comparative genome assembly.gap closing is considered one of the most challenging and time-consuming tasks in bacterial genome sequencing projects, especially with the emergence of new sequencing technologies, such as pyrosequencing, which may result in large amounts of data without the benefit of large insert libraries for contig scaffolding. we propose a novel algorithm to align contigs with more than one reference genome at a time. this approach can successfully overcome the limitations of low degrees of conserved gene ...200818445633
detection of respiratory pathogens in porcine lung tissue and lavage fluid.the objective of this study was to compare the detection rate of bacterial agents in bronchoalveolar lavage fluid (balf), taken without visual control, to that in affected lung tissue obtained from the same pig at necropsy. balf and affected lung tissue were examined for mycoplasma hyopneumoniae using pcr, and standard cultural methods were used for actinobacillus pleuropneumoniae, bordetella bronchiseptica, haemophilus parasuis, pasteurella multocida and streptococcus suis. all pigs with a hist ...200817339121
precarious balance: th17 cells in host defense.lineage-specific responses from the effector t-cell repertoire form a critical component of adaptive immunity. the recent identification of th17 cells-a third, distinct lineage of helper t cells-collapses the long-accepted paradigm in which th1 and th2 cells distinctly mediate cellular and humoral immunity, respectively. in this minireview, we discuss the involvement of the th17 lineage during infection by extracellular bacteria, intracellular bacteria, and fungi. emerging trends suggest that th ...200919901061
precarious balance: th17 cells in host defense.lineage-specific responses from the effector t-cell repertoire form a critical component of adaptive immunity. the recent identification of th17 cells-a third, distinct lineage of helper t cells-collapses the long-accepted paradigm in which th1 and th2 cells distinctly mediate cellular and humoral immunity, respectively. in this minireview, we discuss the involvement of the th17 lineage during infection by extracellular bacteria, intracellular bacteria, and fungi. emerging trends suggest that th ...200919901061
bioshock: biotechnology and bioterrorism.in the recent past, the threat of a global bioterrorist attack has increased dramatically. in addition to the already existing microorganisms and techniques, the recent explosion in biotechnology has considerably added to the arsenal of the bioterrorist. molecular technologies are now available which can be used by committed bioterrorist groups to manipulate and modify microorganisms so as to make them increasingly infectious, virulent or treatment resistant for causing maximum casualties. infec ...200927408292
performance of transport and selective media for swine bordetella bronchiseptica recovery and it comparison to polymerase chain reaction detection.three comparative assays were performed seeking to improve the sensitivity of the diagnosis of bordetella bronchiseptica infection analyzing swine nasal swabs. an initial assay compared the recovery of b. bronchiseptica from swabs simultaneously inoculated with b. bronchiseptica and some interfering bacteria, immersed into three transport formulations (amies with charcoal, trypticase soy broth and phosphate buffer according to soerensen supplemented with 5% of bovine fetal serum) and submitted t ...200924031390
the roles of antimicrobial peptides in innate host defense.antimicrobial peptides (amps) are multi-functional peptides whose fundamental biological role in vivo has been proposed to be the elimination of pathogenic microorganisms, including gram-positive and -negative bacteria, fungi, and viruses. genes encoding these peptides are expressed in a variety of cells in the host, including circulating phagocytic cells and mucosal epithelial cells, demonstrating a wide range of utility in the innate immune system. expression of these genes is tightly regulate ...200919601838
spontaneous pathology of the common marmoset (callithrix jacchus) and tamarins (saguinus oedipus, saguinus mystax).marmosets and tamarins are increasingly used in research, but their pathology remains poorly defined compared with old world primates.200919522731
the vitamin d connection to pediatric infections and immune function.over the past 20 y, a resurgence in vitamin d deficiency and nutritional rickets has been reported throughout the world, including the united states. inadequate serum vitamin d concentrations have also been associated with complications from other health problems, including tuberculosis, cancer (prostate, breast, and colon), multiple sclerosis, and diabetes. these findings support the concept of vitamin d possessing important pleiotropic actions outside of calcium homeostasis and bone metabolism ...200919190532
il-17 and anti-bacterial immunity: protection versus tissue damage.il-17 can impact health in a variety of ways. it is protective for some pathogens but it is also associated with tissue damaging inflammation. by examining the role of il-17 in a variety of bacterial infections the mechanisms by which this cytokine mediates both protection and damage can be dissected. a key element in understanding the role of this cytokine is determining where and when it is acting. dissecting its essential protective role from its immunopathologic role will allow for improved ...200919283706
mechanisms of neutrophil accumulation in the lungs against bacteria.bacterial lung diseases are a major cause of morbidity and mortality both in immunocompromised and in immunocompetent individuals. neutrophil accumulation, a pathological hallmark of bacterial diseases, is critical to host defense, but may also cause acute lung injury/acute respiratory distress syndrome. toll-like receptors, nucleotide-binding oligomerization domain (nod)-like receptors, transcription factors, cytokines, and chemokines play essential roles in neutrophil sequestration in the lung ...200919738160
mechanisms of neutrophil accumulation in the lungs against bacteria.bacterial lung diseases are a major cause of morbidity and mortality both in immunocompromised and in immunocompetent individuals. neutrophil accumulation, a pathological hallmark of bacterial diseases, is critical to host defense, but may also cause acute lung injury/acute respiratory distress syndrome. toll-like receptors, nucleotide-binding oligomerization domain (nod)-like receptors, transcription factors, cytokines, and chemokines play essential roles in neutrophil sequestration in the lung ...200919738160
enantioselective protonation.enantioselective protonation is a common process in biosynthetic sequences. the decarboxylase and esterase enzymes that effect this valuable transformation are able to control both the steric environment around the proton acceptor (typically an enolate) and the proton donor (typically a thiol). recently, several chemical methods to achieve enantioselective protonation have been developed by exploiting various means of enantiocontrol in different mechanisms. these laboratory transformations have ...200920428461
shifting the genomic gold standard for the prokaryotic species definition.dna-dna hybridization (ddh) has been used for nearly 50 years as the gold standard for prokaryotic species circumscriptions at the genomic level. it has been the only taxonomic method that offered a numerical and relatively stable species boundary, and its use has had a paramount influence on how the current classification has been constructed. however, now, in the era of genomics, ddh appears to be an outdated method for classification that needs to be substituted. the average nucleotide identi ...200919855009
bordetella bsp22 forms a filamentous type iii secretion system tip complex and is immunoprotective in vitro and in vivo.type iii secretion system (t3ss) tip complexes serve as adaptors that bridge the t3ss needle and the pore-forming translocation apparatus. in this report we demonstrate that bsp22, the most abundantly secreted substrate of the bordetella t3ss, self-polymerizes to form the bordetella bronchiseptica tip complex. bsp22 is required for both t3ss-mediated cytotoxicity against eukaryotic cells and haemoglobin release from erythrocytes. bacterial two-hybrid analysis and protein pull-down assays demonst ...200919040642
natural-host animal models indicate functional interchangeability between the filamentous haemagglutinins of bordetella pertussis and bordetella bronchiseptica and reveal a role for the mature c-terminal domain, but not the rgd motif, during infection.bacteria of the bordetella genus cause respiratory tract infections. both broad host range (e.g. bordetella bronchiseptica) and human-adapted (e.g. bordetella pertussis) strains produce a surface-exposed and secreted protein called filamentous haemagglutinin (fha) that functions in adherence and immunomodulation. previous studies using b. pertussis and cultured mammalian cells identified several fha domains with potential roles in host cell interactions, including an arg-gly-asp (rgd) triplet th ...200919220744
anthrax edema toxin induces maturation of dendritic cells and enhances chemotaxis towards macrophage inflammatory protein 3beta.bacillus anthracis secretes two bipartite toxins, edema toxin (et) and lethal toxin (lt), which impair immune responses and contribute directly to the pathology associated with the disease anthrax. edema factor, the catalytic subunit of et, is an adenylate cyclase that impairs host defenses by raising cellular cyclic amp (camp) levels. synthetic camp analogues and compounds that raise intracellular camp levels lead to phenotypic and functional changes in dendritic cells (dcs). here, we demonstra ...200919273556
structural and functional similarities between a ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco)-like protein from bacillus subtilis and photosynthetic rubisco.the sequences classified as genes for various ribulose-1,5-bisphosphate (rubp) carboxylase/oxygenase (rubisco)-like proteins (rlps) are widely distributed among bacteria, archaea, and eukaryota. in the phylogenic tree constructed with these sequences, rubiscos and rlps are grouped into four separate clades, forms i-iv. in rubisco enzymes encoded by form i, ii, and iii sequences, 19 conserved amino acid residues are essential for co(2) fixation; however, 1-11 of these 19 residues are substituted ...200919279009
characterization of wbpb, wbpe, and wbpd and reconstitution of a pathway for the biosynthesis of udp-2,3-diacetamido-2,3-dideoxy-d-mannuronic acid in pseudomonas aeruginosa.the lipopolysaccharide of pseudomonas aeruginosa pao1 contains an unusual sugar, 2,3-diacetamido-2,3-dideoxy-d-mannuronic acid (d-mannac3naca). wbpb, wbpe, and wbpd are thought to encode oxidase, transaminase, and n-acetyltransferase enzymes. to characterize their functions, recombinant proteins were overexpressed and purified from heterologous hosts. activities of his(6)-wbpb and his(6)-wbpe were detected only when both proteins were combined in the same reaction. using a direct maldi-tof mass ...200919282284
the complete genome and proteome of laribacter hongkongensis reveal potential mechanisms for adaptations to different temperatures and habitats.laribacter hongkongensis is a newly discovered gram-negative bacillus of the neisseriaceae family associated with freshwater fish-borne gastroenteritis and traveler's diarrhea. the complete genome sequence of l. hongkongensis hlhk9, recovered from an immunocompetent patient with severe gastroenteritis, consists of a 3,169-kb chromosome with g+c content of 62.35%. genome analysis reveals different mechanisms potentially important for its adaptation to diverse habitats of human and freshwater fish ...200919283063
evolution of acute infections and the invasion-persistence trade-off.we seek to understand the conditions favoring the evolution of acute, highly transmissible infections. most work on the life-history evolution of pathogens has focused on the transmission-virulence trade-off. here we focus on a distinct trade-off that operates, even among avirulent pathogens, between a pathogen's speed of invasion and its ability to persist in a finite host population. other authors have shown how this invasion-persistence trade-off can lead to intermediate pathogen attack rates ...200919231966
euthanasia of neonatal rats with carbon dioxide.exposure to co(2) is a common method used to euthanize rodents in biomedical research and rodent production. the purpose of this study was to determine the length of co(2) exposure required to euthanize neonatal rats (0 to 10 d old). multiple groups of rats were exposed to 100% co(2) for 5 to 60 min. after co(2) exposure, rats were placed in room air for 20 min to allow for possible recovery. no difference was found in comparing 1 inbred strain and 1 outbred stock of rats. time to death varied i ...200919245746
th17 cells at the crossroads of innate and adaptive immunity against infectious diseases at the mucosa.t helper type 17 (th17) cells are a distinct lineage of t cells that produce the effector molecules il-17, il-17f, il-21, and il-22. although the role of th17 cells in autoimmunity is well documented, there is growing evidence that the th17 lineage and other interleukin (il)-17-producing cells are critical for host defense against bacterial, fungal, and viral infections at mucosal surfaces. here we summarize recent progress in our understanding of the function of il-17-producing cells as a bridg ...200919587639
the pgaabcd locus of acinetobacter baumannii encodes the production of poly-beta-1-6-n-acetylglucosamine, which is critical for biofilm formation.we found that acinetobacter baumannii contains a pgaabcd locus that encodes proteins that synthesize cell-associated poly-beta-(1-6)-n-acetylglucosamine (pnag). both a mutant with an in-frame deletion of the pga locus (s1deltapga) and a transcomplemented strain (s1deltapga-c) of a. baumannii were constructed, and the pnag production by these strains was compared using an immunoblot assay. deleting the pga locus resulted in an a. baumannii strain without pnag, and transcomplementation of the s1de ...200919633088
rapid real-time pcr assays for detection of klebsiella pneumoniae with the rmpa or maga genes associated with the hypermucoviscosity phenotype: screening of nonhuman primates.the relationship of mucoviscosity-associated (maga) and/or regulator of mucoid phenotype (rmpa) genes to the klebsiella pneumoniae hypermucoviscosity (hmv) phenotype has been reported. we previously demonstrated that rmpa+ k. pneumoniae can cause serious disease in african green monkeys and isolated rmpa+ and maga+ hmv k. pneumoniae from other species of non-human primates. to rapidly screen african green monkeys/non-human primates for these infections, we developed three real-time pcr assays. t ...200919644019
bordetella bronchiseptica infection in cats. abcd guidelines on prevention and management.overview: bordetella bronchiseptica is a gram-negative bacterium that colonises the respiratory tract of mammals and is considered to be a primary pathogen of domestic cats. it is sensible to consider b bronchiseptica as a rare cause of zoonotic infections. the bacterium is susceptible to common disinfectants. infection: the bacterium is shed in oral and nasal secretions of infected cats. dogs with respiratory disease are an infection risk for cats. the microorganism colonises the ciliated epith ...200919481041
klebsiella pneumoniae triggers a cytotoxic effect on airway epithelial cells.klebsiella pneumoniae is a capsulated gram negative bacterial pathogen and a frequent cause of nosocomial infections. despite its clinical relevance, little is known about the features of the interaction between k. pneumoniae and lung epithelial cells on a cellular level, neither about the role of capsule polysaccharide, one of its best characterised virulence factors, in this interaction.200919650888
vibriobactin antibodies: a vaccine strategy.a new target strategy in the development of bacterial vaccines, the induction of antibodies to microbial outer membrane ferrisiderophore complexes, is explored. a vibriobactin (vib) analogue, with a thiol tether, 1-(2,3-dihydroxybenzoyl)-5,9-bis[[(4s,5r)-2-(2,3-dihydroxyphenyl)-4,5-dihydro-5-methyl-4-oxazolyl]carbonyl]-14-(3-mercaptopropanoyl)-1,5,9,14-tetraazatetradecane, was synthesized and linked to ovalbumin (ova) and bovine serum albumin (bsa). the antigenicity of the vib microbial iron che ...200919492834
identification of a novel lipopolysaccharide core biosynthesis gene cluster in bordetella pertussis, and influence of core structure and lipid a glucosamine substitution on endotoxic activity.lipopolysaccharide (lps), also known as endotoxin, is one of the main constituents of the gram-negative bacterial outer membrane. whereas the lipid a portion of lps is generally considered the main determinant for endotoxic activity, the oligosaccharide moiety plays an important role in immune evasion and the interaction with professional antigen-presenting cells. here we describe a novel four-gene cluster involved in the biosynthesis of the bordetella pertussis core oligosaccharide. by insertio ...200919364841
bordetella bronchiseptica aroa mutant as a live vaccine vehicle for heterologous porcine circovirus type 2 major capsid protein expression.porcine circovirus type 2 (pcv2) infections cause important respiratory diseases in the pig industry and are associated with many bacterial, mycoplasmal, and viral complications. in this study, a heterologous pcv2 major capsid protein (mcp) was expressed in the bordetella bronchiseptica aroa mutant strain (bbs-mcp) and used as a live vaccine vehicle. mice and pigs were immunized with live bbs-mcp via the intranasal route. the antibodies against mcp were induced successfully in the serum as deter ...200919428194
[characterization of attenuated salmonella c500 strain with a delta asd mutant and use as an asd+ balanced-lethal host-vector system].salmonella enterica serovar choleraesuis strain c500 is a live, attenuated vaccine that has been used in china for over 40 years to prevent piglet paratyphoid. the objective of this study was to evaluate the potential of attenuated salmonella enterica serovar choleraesuis c500 strain with a delta asd mutant as an effective live vaccine vector by the asd+ balanced-lethal host-vector system. here, we compared the characteristics of s. enterica serovar choleraesuis delta asdc500 strain with the par ...200919441223
cxcr2-dependent mucosal neutrophil influx protects against colitis-associated diarrhea caused by an attaching/effacing lesion-forming bacterial pathogen.enteropathogenic escherichia coli (epec) is a major cause of diarrheal disease in young children, yet symptoms and duration are highly variable for unknown reasons. citrobacter rodentium, a murine model pathogen that shares important functional features with epec, colonizes mice in colon and cecum and causes inflammation, but typically little or no diarrhea. we conducted genome-wide microarray studies to define mechanisms of host defense and disease in c. rodentium infection. a significant fract ...200919675161
efflux-mediated drug resistance in bacteria: an update.drug efflux pumps play a key role in drug resistance and also serve other functions in bacteria. there has been a growing list of multidrug and drug-specific efflux pumps characterized from bacteria of human, animal, plant and environmental origins. these pumps are mostly encoded on the chromosome, although they can also be plasmid-encoded. a previous article in this journal provided a comprehensive review regarding efflux-mediated drug resistance in bacteria. in the past 5 years, significant pr ...200919678712
porcine abortion outbreak associated with toxoplasma gondii in jeju island, korea.this report deals with the acute onset of an abortion outbreak and high sow mortality in one pig herd consisted of 1,200 pigs and 120 sows on jeju island, korea. affected pregnant sows showed clinical signs, including high fever, gradual anorexia, vomiting, depression, recumbency, prostration, abortion, and a few deaths. four dead sows, five aborted fetuses from the same litter, and 17 sera collected from sows infected or normal were submitted to the pathology division of the national veterinary ...200919461210
proficiency program for real-time pcr diagnosis of bordetella pertussis infections in french hospital laboratories and at the french national reference center for whooping cough and other bordetelloses.with the support of a ministerial program for innovative and expensive technologies, dedicated to the economic evaluation of laboratory diagnosis of pertussis by real-time pcr, external quality assessment for real-time is481 pcr was carried out. coordinated by the national centre of reference of pertussis and other bordetelloses (ncr), this study aimed to harmonize and to assess the performances of eight participating microbiology hospital laboratories throughout the french territory. between ja ...200919692562
effect of a novel nop receptor agonist (sch 225288) on guinea pig irritant-evoked, feline mechanically induced and canine infectious tracheobronchitis cough.previous studies have demonstrated that nociceptin/orphanin fq (n/ofq), the endogenous peptide ligand for the g-protein-coupled nop receptor, inhibits cough in experimental models. sch 225288 is a nonpeptide, orally active nop agonist that may provide the foundation for the development of novel treatments for cough.200919696521
comparison of side effects between buprenorphine and meloxicam used postoperatively in dutch belted rabbits (oryctolagus cuniculus).one of the challenges facing veterinarians and investigators who use rabbits (oryctolagus cuniculus) as a surgical model in biomedical research is choosing an appropriate and efficacious postoperative analgesic without systemic complications and side effects. the objective of this study was to evaluate the gastrointestinal side effects associated with the postoperative use of buprenorphine in dutch belted rabbits. we also evaluated the analgesic meloxicam as an alternative to opioid administrati ...200919476717
new yeast recombineering tools for bacteria.recombineering with saccharomyces cerevisiae is a powerful methodology that can be used to clone multiple unmarked pieces of dna to generate complex constructs with high efficiency. here, we introduce two new tools that utilize the native recombination enzymes of s. cerevisiae to facilitate the manipulation of dna. first, yeast recombineering was used to make directed nested deletions in a bacteria-yeast shuttle plasmid using only one or two single stranded oligomers, thus obviating the need for ...200919477196
evidence for horizontal gene transfer of two antigenically distinct o antigens in bordetella bronchiseptica.host immunity is a major driving force of antigenic diversity, resulting in pathogens that can evade immunity induced by closely related strains. here we show that two bordetella bronchiseptica strains, rb50 and 1289, express two antigenically distinct o-antigen serotypes (o1 and o2, respectively). when 18 additional b. bronchiseptica strains were serotyped, all were found to express either the o1 or o2 serotype. comparative genomic hybridization and pcr screening showed that the expression of e ...200919528223
successful management of rabbit anesthesia through the use of nasotracheal intubation.although nasotracheal intubation in the rabbit has been briefly described, scientific assessment of the procedure has not been reported. in this report we describe nasotracheal intubation performed in 38 male new zealand white rabbits (3.0 to 5.5 kg) used for a vascular patch study. the rabbits were placed under general anesthesia twice, with 2 mo between the initial and final intubations. rabbits were intubated by the oral or nasotracheal route and compared. previous literature dismissed nasotr ...200919383213
a novel isoquinoline alkaloid, dd-carboxypeptidase inhibitor, with antibacterial activity isolated from streptomyces sp. 8812. part i: taxonomy, fermentation, isolation and biological activities.a novel isoquinoline alkaloid of molecular formula c10h9no4, labeled js-1, was isolated from the culture broth of streptomyces sp. 8812. it was purified by acetone protein precipitation from the culture supernatant, followed by anion exchange and c18 rp hplc columns. js-1 is an inhibitor of exocellular dd-carboxypeptidases/transpeptidases (dd-peptidases) 64-575 ii from saccharopolyspora erythraea 64-575 ii, and r39 from actinomadura r39. js-1 exhibits activity against gram-negative bacteria, suc ...200919713994
genomic analysis of the adenylate cyclase-hemolysin c-terminal region of bordetella pertussis, bordetella parapertussis and bordetella bronchiseptica.adenylate cyclase-hemolysin plays an important role in the virulence of bordetella pertussis, bordetella parapertussis and bordetella bronchiseptica species. its c-terminal region carries protective epitopes and receptor binding site for human cells. genomic analyses of this region indicate no polymorphism in b. pertussis and b. parapertussis regions, but substantial variability in b. bronchiseptica that might be linked to the various niches of this species.200919379809
the effect of the nonionic block copolymer pluronic p85 on gene expression in mouse muscle and antigen-presenting cells.dna vaccines can be greatly improved by polymer agents that simultaneously increase transgene expression and activate immunity. we describe here pluronic p85 (p85), a triblock copolymer of ethylene oxide (eo) and propylene oxide (po) eo(26)-po(40)-eo(26). using a mouse model we demonstrate that co-administration of a bacterial plasmid dna with p85 in a skeletal muscle greatly increases gene expression in the injection site and distant organs, especially the draining lymph nodes and spleen. the r ...200919064283
relapsing peritonitis caused by bordetella bronchiseptica in continuous ambulatory peritoneal dialysis patient: a case report.bordetella (b) bronchiseptica is a common veterinary pathogen, but has rarely been implicated in human infections. most patients with b. bronchiseptica infections are compromised clinically such as in patients with a malignancy, aids, malnutrition, or chronic renal failure. we experienced a case of relapsing peritonitis caused by b. bronchiseptica associated with continuous ambulatory peritoneal dialysis (capd). a 56-yr-old male, treated with capd due to end stage renal disease (esrd), was admit ...200919194556
the effect of the nonionic block copolymer pluronic p85 on gene expression in mouse muscle and antigen-presenting cells.dna vaccines can be greatly improved by polymer agents that simultaneously increase transgene expression and activate immunity. we describe here pluronic p85 (p85), a triblock copolymer of ethylene oxide (eo) and propylene oxide (po) eo(26)-po(40)-eo(26). using a mouse model we demonstrate that co-administration of a bacterial plasmid dna with p85 in a skeletal muscle greatly increases gene expression in the injection site and distant organs, especially the draining lymph nodes and spleen. the r ...200919064283
active and passive immunizations with bordetella colonization factor a protect mice against respiratory challenge with bordetella bronchiseptica.bordetella colonization factor a (bcfa) is an outer membrane immunogenic protein, which is critical for efficient colonization of the murine respiratory tract. these properties of bcfa prompted us to examine its utility in inducing a protective immune response against bordetella bronchiseptica in a mouse model of intranasal infection. mice vaccinated with bcfa demonstrated reduced pathology in the lungs and harbored lower bacterial burdens in the respiratory tract. immunization with bcfa led to ...200919064638
safety and efficacy of neonatal vaccination.newborns have an immature immune system that renders them at high risk for infection while simultaneously reducing responses to most vaccines, thereby posing challenges in protecting this vulnerable population. nevertheless, certain vaccines, such as bcg and hepatitis b vaccine, do demonstrate safety and some efficacy at birth, providing proof of principal that certain antigen-adjuvant combinations are able to elicit protective neonatal responses. moreover, birth is a major point of healthcare c ...200919089811
post-assembly modification of bordetella bronchiseptica o polysaccharide by a novel periplasmic enzyme encoded by wbme.bordetella bronchiseptica is a pathogen of humans and animals that colonizes the respiratory tract. it produces a lipopolysaccharide o antigen that contains a homopolymer of 2,3-dideoxy-2,3-diacetamido-l-galacturonic acid (l-galnac3naca). some of these sugars are found in the uronamide form (l-galnac3nacan), and there is no discernible pattern in the distribution of amides along the chain. a b. bronchiseptica wbme mutant expresses an o polysaccharide unusually rich in uronamides. the wbme protei ...200919015265
emergence of quinolone-resistant bordetella pertussis in japan.six bordetella pertussis strains isolated from children in japan from 2004 to 2006 showed high-level resistance to nalidixic acid (nal; mic, >256 microg/ml) and decreased susceptibilities to fluoroquinolones. all of the nal-resistant strains had the same d87g mutation in gyra.200919414571
making the cut: central roles of intramembrane proteolysis in pathogenic microorganisms.proteolysis in cellular membranes to liberate effector domains from their transmembrane anchors is a well-studied regulatory mechanism in animal biology and disease. by contrast, the function of intramembrane proteases in unicellular organisms has received little attention. recent progress has now established that intramembrane proteases execute pivotal roles in a range of pathogens, from regulating mycobacterium tuberculosis envelope composition, cholera toxin production, bacterial adherence an ...200919421188
antibody-mediated immunity to the obligate intracellular bacterial pathogen coxiella burnetii is fc receptor- and complement-independent.the obligate intracellular bacterial pathogen coxiella burnetii causes the zoonosis q fever. the intracellular niche of c. burnetii has led to the assumption that cell-mediated immunity is the most important immune component for protection against this pathogen. however, passive immunization with immune serum can protect naïve animals from challenge with virulent c. burnetii, indicating a role for antibody (ab) in protection. the mechanism of this ab-mediated protection is unknown. therefore, we ...200919426498
temporal signaling and differential expression of bordetella iron transport systems: the role of ferrimones and positive regulators.the bacterial respiratory pathogens bordetella pertussis and bordetella bronchiseptica employ multiple alternative iron acquisition pathways to adapt to changes in the mammalian host environment during infection. the alcaligin, enterobactin, and heme utilization pathways are differentially expressed in response to the cognate iron source availability by a mechanism involving substrate-inducible positive regulators. as inducers, the iron sources function as chemical signals termed ferrimones. fer ...200919130264
immunodominance in mouse and human cd4+ t-cell responses specific for the bordetella pertussis virulence factor p.69 pertactin.p.69 pertactin (p.69 prn), an adhesion molecule from the causative agent of pertussis, bordetella pertussis, is present in cellular and most acellular vaccines that are currently used worldwide. although both humoral immunity and cellular immunity directed against p.69 prn have been implicated in protective immune mechanisms, the identities of cd4(+) t-cell epitopes on the p.69 prn protein remain unknown. here, a single i-a(d)-restricted b. pertussis conserved cd4(+) t-cell epitope at the n term ...200919015250
role of hrpa in biofilm formation of neisseria meningitidis and regulation of the hrpbas transcripts.two-partner secretion systems of gram-negative organisms are utilized in adherence, invasion, and biofilm formation. the hrpab proteins of neisseria meningitidis are members of a two-partner secretion system, and hrpa is established as being important to adherence and intracellular escape. this study set out to determine the expression pattern of members of the hrpbas putative operon and to find a functional role for the hrpa protein. the upregulation of these genes was found in situations of an ...200919289515
constitutive and regulated expression vectors to construct polyphosphate deficient bacteria.inorganic polyphosphate (polyp), a polymer of tens or hundreds of phosphate residues linked by atp-like bonds, is found in all organisms and performs a wide variety of functions. polyp is synthesized in bacterial cells by the actions of polyphosphate kinases (ppk1 and ppk2) and degraded by an exopolyphosphatase (ppx). bacterial cells with polyp deficiencies are impaired in many structural and important cellular functions such as motility, quorum sensing, biofilm formation and virulence. knockout ...200919323822
genomic evidence for the evolution of streptococcus equi: host restriction, increased virulence, and genetic exchange with human pathogens.the continued evolution of bacterial pathogens has major implications for both human and animal disease, but the exchange of genetic material between host-restricted pathogens is rarely considered. streptococcus equi subspecies equi (s. equi) is a host-restricted pathogen of horses that has evolved from the zoonotic pathogen streptococcus equi subspecies zooepidemicus (s. zooepidemicus). these pathogens share approximately 80% genome sequence identity with the important human pathogen streptococ ...200919325880
role of cold shock proteins in growth of listeria monocytogenes under cold and osmotic stress conditions.the gram-positive bacterium listeria monocytogenes is a food-borne pathogen of both public health and food safety significance. it possesses three small, highly homologous protein members of the cold shock protein (csp) family. we used gene expression analysis and a set of mutants with single, double, and triple deletions of the csp genes to evaluate the roles of cspa, cspb, and cspd in the cold and osmotic (nacl) stress adaptation responses of l. monocytogenes. all three csps are dispensable fo ...200919151183
isolation, antimicrobial resistance, and virulence genes of pasteurella multocida strains from swine in china.a total of 233 isolates of pasteurella multocida were obtained from 2,912 cases of clinical respiratory disease in pigs in china, giving an isolation rate of 8.0%. serogroup a p. multocida isolates were isolated from 92 cases (39.5%), and serogroup d isolates were isolated from 128 cases (54.9%); 12 isolates (5.2%) were untypeable. p. multocida was the fourth most frequent pathogenic bacterium recovered from the respiratory tract, after streptococcus suis, haemophilus parasuis, and escherichia c ...200919158260
isolation of bordetella avium and novel bordetella strain from patients with respiratory disease.bordetella avium is thought to be strictly an avian pathogen. however, 16s rrna gene sequencing identified 2 isolates from 2 humans with respiratory disease as b. avium and a novel b. avium-like strain. thus, b. avium and b. avium-like organisms are rare opportunistic human pathogens.200919116056
the role of macrophages in optic nerve regeneration.following injury to the nervous system, the activation of macrophages, microglia, and t-cells profoundly affects the ability of neurons to survive and to regenerate damaged axons. the primary visual pathway provides a well-defined model system for investigating the interactions between the immune system and the nervous system after neural injury. following damage to the optic nerve in mice and rats, retinal ganglion cells, the projection neurons of the eye, normally fail to regenerate their axon ...200918708126
the role of macrophages in optic nerve regeneration.following injury to the nervous system, the activation of macrophages, microglia, and t-cells profoundly affects the ability of neurons to survive and to regenerate damaged axons. the primary visual pathway provides a well-defined model system for investigating the interactions between the immune system and the nervous system after neural injury. following damage to the optic nerve in mice and rats, retinal ganglion cells, the projection neurons of the eye, normally fail to regenerate their axon ...200918708126
virulence factor secretion and translocation by bordetella species.here we review the bordetella virulence secretome with an emphasis on factors that translocate into target cells. recent advances in understanding the functions of adenylate cyclase toxin, a type 1 secretion system (t1ss) substrate, and pertussis toxin, a type iv secretion system (t4ss) substrate, are briefly described and a compilation of additional secretion systems and secreted factors is provided. particular attention is devoted to the bsc type iii secretion system (t3ss) and controversies s ...200919186097
species distribution and antimicrobial susceptibility of gram-negative aerobic bacteria in hospitalized cancer patients.nosocomial infections pose significant threats to hospitalized patients, especially the immunocompromised ones, such as cancer patients.200919228413
constraint-based network model of pathogen-immune system interactions.pathogenic bacteria such as bordetella bronchiseptica modulate host immune responses to enable their establishment and persistence; however, the immune response is generally successful in clearing these bacteria. here, we model the dynamic outcome of the interplay between host immune components and b. bronchiseptica virulence factors. the model extends our previously published interaction network of b. bronchiseptica and includes the existing experimental information on the relative timing of il ...200918952547
altered bone marrow dendritic cell cytokine production to toll-like receptor and cd40 ligation during chronic feline immunodeficiency virus infection.impaired dendritic cell (dc) function is thought to be central to human immunodeficiency virus-associated immunodeficiency. in this study, we examined the effect of chronic feline immunodeficiency virus (fiv) infection on dc cytokine production in response to microbial and t-cell stimulation. cytokine production after either toll-like receptor (tlr) or cd40 ligation in bone marrow-derived dcs (bm-dcs) was measured in naïve and chronically fiv-infected cats. the bm-dcs were stimulated with ligand ...200918775027
immunogenicity of recombinant protective antigen and efficacy against intranasal challenge with bordetella bronchiseptica.bordetella bronchiseptica is a gram-negative respiratory pathogen that causes substantial disease in a variety of animals. filamentous hemagglutinin (fha) and pertactin are important attachment factors and protective immunogens, which serve as protective antigens in several animal models of infection with b. bronchiseptica. here, we showed the efficacy of subcutaneous immunization of mice with a recombinant protein rf1p2, which consisted of the important immunodominant protective type i domain ( ...200918852008
improved prediction of malaria degradomes by supervised learning with svm and profile kernel.the spread of drug resistance through malaria parasite populations calls for the development of new therapeutic strategies. however, the seemingly promising genomics-driven target identification paradigm is hampered by the weak annotation coverage. to identify potentially important yet uncharacterized proteins, we apply support vector machines using profile kernels, a supervised discriminative machine learning technique for remote homology detection, as a complement to the traditional alignment ...200919057851
improved prediction of malaria degradomes by supervised learning with svm and profile kernel.the spread of drug resistance through malaria parasite populations calls for the development of new therapeutic strategies. however, the seemingly promising genomics-driven target identification paradigm is hampered by the weak annotation coverage. to identify potentially important yet uncharacterized proteins, we apply support vector machines using profile kernels, a supervised discriminative machine learning technique for remote homology detection, as a complement to the traditional alignment ...200919057851
evaluation of an immunochromatographic assay kit for rapid identification of mycobacterium tuberculosis complex in clinical isolates.we evaluated a new immunochromatographic assay (ica) using mouse monoclonal anti-mpt64 antibody for rapid discrimination between mycobacterium tuberculosis and nontuberculous mycobacteria in clinical isolates. a study with mycobacteria and other organisms showed excellent sensitivity (approximately equal 99%) and specificity (100%) and an appropriate detection limit (10(5) cfu/ml) when tested with m. tuberculosis h37rv. this ica can simplify the identification of m. tuberculosis in clinical labo ...200919052177
evaluation of an immunochromatographic assay kit for rapid identification of mycobacterium tuberculosis complex in clinical isolates.we evaluated a new immunochromatographic assay (ica) using mouse monoclonal anti-mpt64 antibody for rapid discrimination between mycobacterium tuberculosis and nontuberculous mycobacteria in clinical isolates. a study with mycobacteria and other organisms showed excellent sensitivity (approximately equal 99%) and specificity (100%) and an appropriate detection limit (10(5) cfu/ml) when tested with m. tuberculosis h37rv. this ica can simplify the identification of m. tuberculosis in clinical labo ...200919052177
contribution of bordetella bronchiseptica filamentous hemagglutinin and pertactin to respiratory disease in swine.bordetella bronchiseptica is pervasive in swine populations and plays multiple roles in respiratory disease. most studies addressing virulence factors of b. bronchiseptica are based on isolates derived from hosts other than pigs. two well-studied virulence factors implicated in the adhesion process are filamentous hemagglutinin (fha) and pertactin (prn). we hypothesized that both fha and prn would serve critical roles in the adhesion process and be necessary for colonization of the swine respira ...200919237531
role of neutrophils in response to bordetella pertussis infection in mice.pertussis is an acute respiratory disease caused by the bacterium bordetella pertussis, for which humans are the only known reservoir. during infection, b. pertussis releases several toxins, including pertussis toxin (pt) and adenylate cyclase toxin (act), which have both been shown to play roles in promoting bacterial growth during early infection in a mouse model. furthermore, in vitro and in vivo studies suggest that pt and act affect neutrophil chemotaxis and/or function, thereby altering th ...200919103765
role of neutrophils in response to bordetella pertussis infection in mice.pertussis is an acute respiratory disease caused by the bacterium bordetella pertussis, for which humans are the only known reservoir. during infection, b. pertussis releases several toxins, including pertussis toxin (pt) and adenylate cyclase toxin (act), which have both been shown to play roles in promoting bacterial growth during early infection in a mouse model. furthermore, in vitro and in vivo studies suggest that pt and act affect neutrophil chemotaxis and/or function, thereby altering th ...200919103765
the piglet as a model for b cell and immune system development.the ability to identify factors responsible for disease in all species depends on the ability to separate those factors which are environmental from those that are intrinsic. this is particularly important for studies on the development of the adaptive immune response of neonates. studies on laboratory rodents or primates have been ambiguous because neither the effect of environmental nor maternal factors on the newborn can be controlled in mammals that: (i) transmit potential maternal immunoreg ...200919056129
clinical and laboratory evidence for neisseria meningitidis biofilms.neisseria meningitidis is the etiologic agent of meningococcal meningitis. carriage of the organism is approximately 10% while active disease occurs at a rate of 1:100,000. recent publications demonstrate that n. meningitidis has the ability to form biofilms on glass, plastic or cultured human bronchial epithelial cells. microcolony-like structures are also observed in histological sections from patients with active meningococcal disease. this review investigates the possible role of meningococc ...200919492966
the piglet as a model for b cell and immune system development.the ability to identify factors responsible for disease in all species depends on the ability to separate those factors which are environmental from those that are intrinsic. this is particularly important for studies on the development of the adaptive immune response of neonates. studies on laboratory rodents or primates have been ambiguous because neither the effect of environmental nor maternal factors on the newborn can be controlled in mammals that: (i) transmit potential maternal immunoreg ...200919056129
molecular determinants of the interaction between clostridium perfringens enterotoxin fragments and claudin-3.clostridium perfringens enterotoxin (cpe) binds to the extracellular loop 2 of a subset of claudins, e.g. claudin-3. here, the molecular mechanism of the cpe-claudin interaction was analyzed. using peptide arrays, recombinant cpe-(116-319) bound to loop 2 peptides of mouse claudin-3, -6, -7, -9, and -14 but not of 1, 2, 4, 5, 8, 10-13, 15, 16, 18-20, and 22. substitution peptide mapping identified the central motif (148)npl(150)vp, supposed to represent a turn region in the loop 2, as essential ...200919429681
genomic and genetic analyses of diversity and plant interactions of pseudomonas fluorescens.pseudomonas fluorescens are common soil bacteria that can improve plant health through nutrient cycling, pathogen antagonism and induction of plant defenses. the genome sequences of strains sbw25 and pf0-1 were determined and compared to each other and with p. fluorescens pf-5. a functional genomic in vivo expression technology (ivet) screen provided insight into genes used by p. fluorescens in its natural environment and an improved understanding of the ecological significance of diversity with ...200919432983
pseudogene accumulation in the evolutionary histories of salmonella enterica serovars paratyphi a and typhi.of the > 2000 serovars of salmonella enterica subspecies i, most cause self-limiting gastrointestinal disease in a wide range of mammalian hosts. however, s. enterica serovars typhi and paratyphi a are restricted to the human host and cause the similar systemic diseases typhoid and paratyphoid fever. genome sequence similarity between paratyphi a and typhi has been attributed to convergent evolution via relatively recent recombination of a quarter of their genomes. the accumulation of pseudogene ...200919159446
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