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chronic prostatitis due to yersinia pseudotuberculosis. 19989508336
[a combined outbreak of intestinal yersiniosis and pseudotuberculosis in a children's health-promotion camp]. 19989532706
yopj of yersinia pseudotuberculosis is required for the inhibition of macrophage tnf-alpha production and downregulation of the map kinases p38 and jnk.exposure of macrophages to lipopolysaccharide (lps) leads to production of the pro-inflammatory cytokine, tumour necrosis factor alpha (tnf-alpha). previous studies have suggested that pathogenic yersinia spp. inhibit lps-mediated production of tnf-alpha in macrophages, and that one of the yop proteins secreted by the plasmid-encoded type iii pathway is required for this activity. we found that tnf-alpha production was inhibited when j774a.1 murine macrophages were infected with wild-type y. pse ...19989535085
investigations into field cases of porcine colitis with particular reference to infection with serpulina pilosicoli.investigations into the possible causes of colitis and typhlocolitis were carried out on 85 pig units in the united kingdom between 1992 and 1996. serpulina pilosicoli was identified most commonly, occurring as the suggested primary agent on 21 (25 per cent) of the units but forming part of mixed infections on another 23 (27 per cent) of the units, the main co-infections being yersinia pseudotuberculosis (eight units), proliferative enteropathy (six units), salmonella species (four units) or ser ...19989549864
clinical and immune peculiarities of pseudotuberculous polyarthritis against a background of chronic opisthorchiasis. 19989566679
the rfb genes in azotobacter vinelandii are arranged in a rfbfgc gene cluster: a significant deviation to the arrangement of the rfb genes in enterobacteriaceae.we report the identification of rfbf and rfbc located adjacent to the previously identified rfbg (gavini et. al. biochem. biophys. res. commun. 1997, 240, 153-161) from the non-symbiotic, non-pathogenic soil bacterium azotobacter vinelandii. the rfbf open reading frame encodes a putative polypeptide of 256 amino acids. this polypeptide shares a homology of 74% with the rfbf of synechocystis sp. and a 70% homology with the asca of yersinia pseudotuberculosis which function as alpha-d-glucose-1-ph ...19989571197
swim analysis allows rapid identification of residues involved in invasin-mediated bacterial uptake.the yersinia pseudotuberculosis invasin protein promotes bacterial uptake into normally non-phagocytic cells. combinations of six alanine substitutions in a region of invasin previously shown to be important for bacterial internalization were analyzed using binomial and codon mutagenesis strategies. a single pool of mutants, potentially containing 64 derivatives with various combinations of alanine substitutions, was enriched by one passage through hep2 cells. dna was isolated from the resulting ...19989573344
yersinia pseudotuberculosis and yersinia pestis are more resistant to bactericidal cationic peptides than yersinia enterocolitica.the action of bactericidal polycationic peptides was compared in yersinia spp. by testing peptide binding to live cells and changes in outer membrane (om) morphology and permeability. moreover, polycation interaction with lps was studied by measuring the dependence of dansylcadaverine displacement and zeta potential on polycation concentration. when growth at 37 degrees c, yersinia pestis and yersinia pseudotuberculosis bound less polymyxin b (pmb) than pathogenic or non-pathogenic yersinia ente ...19989639921
yersinia pseudotuberculosis and yersinia pestis show increased outer membrane permeability to hydrophobic agents which correlates with lipopolysaccharide acyl-chain fluidity.the hydrophobic probe n-phenyl-1-naphthylamine accumulated less in non-pathogenic yersinia spp. and non-pathogenic and pathogenic yersinia enterocolitica than in yersinia pseudotuberculosis or yersinia pestis. this was largely due to differences in the activity of efflux systems, but also to differences in outer membrane permeability because uptake of the probe in kcn/arsenate-poisoned cells was slower in the former group than in y. pseudotuberculosis and y. pestis. the probe accumulation rate w ...19989639922
the yopj locus is required for yersinia-mediated inhibition of nf-kappab activation and cytokine expression: yopj contains a eukaryotic sh2-like domain that is essential for its repressive activity.upon exposure to bacteria, eukaryotic cells activate signalling pathways that result in the increased expression of several defence-related genes. here, we report that the yopj locus of the enteropathogen yersinia pseudotuberculosis encodes a protein that inhibits the activation of nf-kappab transcription factors by a mechanism(s), which prevents the phosphorylation and subsequent degradation of the inhibitor protein ikappab. consequently, eukaryotic cells infected with yopj-expressing yersinia ...19989680199
development of rrna-targeted pcr and in situ hybridization with fluorescently labelled oligonucleotides for detection of yersinia species.in this report, we present details of two rapid molecular detection techniques based on 16s and 23s rrna sequence data to identify and differentiate yersinia species from clinical and environmental sources. near-full-length 16s rrna gene (rdna) sequences for three different yersinia species and partial 23s rdna sequences for three y. pestis and three y. pseudotuberculosis strains were determined. while 16s rdna sequences of y. pestis and y. pseudotuberculosis were found to be identical, one base ...19989705392
yopd of yersinia pseudotuberculosis is translocated into the cytosol of hela epithelial cells: evidence of a structural domain necessary for translocation.yersinia pseudotuberculosis yopb and yopd proteins are essential for translocation of yop effector proteins into the target cell cytosol. yopb is suggested to mediate pore formation in the target cell plasma membrane, allowing translocation of yop effector proteins, although the function of yopd is unclear. to investigate the role in translocation for yopd, a mutant strain in y. pseudotuberculosis was constructed containing an in frame deletion of essentially the entire yopd gene. as shown recen ...19989723919
putative origin of yersinia pseudotuberculosis in western and eastern countries. a comparison of restriction endonuclease analysis of virulence plasmids.yersinia pseudotuberculosis isolates from russia east of moscow, korea and mainland china were used for restriction endonuclease analysis of virulence plasmid (reap) and findings were compared with reap of isolates from japan and western countries. an identical reap pattern of each serogroup 1a, 1b, 3, 4a and 4b strain was observed among isolates from russia, korea, mainland china, and japan but such was absent in west european strains. therefore, the possibility that the origin of y. pseudotube ...19989728409
characterization of a bacteriocin produced by streptococcus thermophilus 81.a new bacteriocin, produced by streptococcus thermophilus 81 has been isolated, purified and characterized. by its heat sensitivity and broad inhibitory spectrum it does not resemble any other s. thermophilus bacteriocin. the mode of action is bacteriostatic. this peptide of 32 amino acids is efficient against several bacillus species, listeria monocytogenes, salmonella typhimurium, escherichia coli, yersinia pseudotuberculosis and yersinia enterocolitica. this bacteriocin is heat labile but its ...19989728685
[the use of a species-specific erythrocytic diagnostic agent for detecting pseudotuberculosis and yersiniosis]. 19989742763
functional gene transfer from intracellular bacteria to mammalian cells.we provide evidence of direct transfer of functional dna from bacteria to mammalian cells. an escherichia coli k12 diaminopimelate auxotroph made invasive by cloning the invasin gene from yersinia pseudotuberculosis transfers dna after simple co-incubation, into a variety of mammalian cell lines. transfer efficiency was enhanced in some cells by coexpression of the gene for listeriolysin from listeria monocytogenes. expression of the acquired genes occurs in both dividing and quiescent cells. th ...19989743121
dna sequencing and analysis of the low-ca2+-response plasmid pcd1 of yersinia pestis kim5.the low-ca2+-response (lcr) plasmid pcd1 of the plague agent yersinia pestis kim5 was sequenced and analyzed for its genetic structure. pcd1 (70,509 bp) has an incfiia-like replicon and a sopabc-like partition region. we have assigned 60 apparently intact open reading frames (orfs) that are not contained within transposable elements. of these, 47 are proven or possible members of the lcr, a major virulence property of human-pathogenic yersinia spp., that had been identified previously in one or ...19989746557
[new method of isolation of o-specific polysaccharide from gram-negative bacteria yersinia pseudotuberculosis].using bacteria yersinia pseudotuberculosis as an example, two procedures for obtaining the o-specific polysaccharide of endotoxins of gram-negative bacteria were compared: the direct acidic hydrolysis of whole cells and the traditional procedure based on preliminary isolation of the corresponding lipopolysaccharide. analysis of the resulting polysaccharides showed that the isolation from the bacterial biomass gave a high yield of the polysaccharide; the polysaccharide is not degraded; and judgin ...19989749318
functional conservation of the effector protein translocators popb/yopb and popd/yopd of pseudomonas aeruginosa and yersinia pseudotuberculosis.virulent yersinia species cause systemic infections in rodents, and y. pestis is highly pathogenic for humans. pseudomonas aeruginosa, on the other hand, is an opportunistic pathogen, which normally infects only compromised individuals. surprisingly, these pathogens both encode highly related contact-dependent secretion systems for the targeting of toxins into eukaryotic cells. in yersinia, yopb and yopd direct the translocation of the secreted yop effectors across the target cell membrane. in t ...19989767584
identification of an amino-terminal substrate-binding domain in the yersinia tyrosine phosphatase that is required for efficient recognition of focal adhesion targets.yoph is a protein tyrosine phosphatase (ptp) that is delivered into host mammalian cells via a type iii secretion pathway in pathogenic yersinia species. although yoph is a highly active ptp, it preferentially targets a subset of tyrosine-phosphorylated proteins in host cells, including p130cas. previous in vitro studies have indicated that the carboxy-terminal ptp domain contributes specificity to the interaction of yoph with substrates. however, it is not known if the ptp domain is sufficient ...19989767593
comparison of systems for identification and differentiation of species within the genus yersinia.of four tested identification systems (api 20e, api rapid 32 ide, micronaut e, and the pcr-based yersinia enterocolitica amplification set), api 20e is still the system of choice for identifying pathogenic yersinia isolates. it provides the highest sensitivity both at the genus and at the species level and has the best cost-effectiveness correlation.19989774596
weak anamnestic responses of inbred mice to yersinia f1 genetic vaccine are overcome by boosting with f1 polypeptide while outbred mice remain nonresponsive.the role of immunity to intracellular ags in resistance to infection by yersinia is not well established. the enteropathogenic bacteria yersinia pseudotuberculosis and yersinia enterocolitica actively translocate ags to the cytosol of eukaryotic cells. whereas yersinia pestis does not always express the requisite cellular adhesins, results have varied as to whether similar cytosolic translocation of ags occurs in vitro. we used a genetic vaccine to induce intracellular expression of the fraction ...19989780193
the identification of exported proteins with gene fusions to invasin.exported proteins are integral to understanding the biology of bacterial organisms. they have special significance in pathogenesis research because they can mediate critical interactions between pathogens and eukaryotic cell surfaces. further, they frequently serve as targets for vaccines and diagnostic tests. the commonly used genetic assays for identifying exported proteins use fusions to alkaline phosphatase or beta-lactamase. these systems are not ideal for identifying outer membrane protein ...19989781883
[an epidemic outbreak of pseudotuberculosis in a boarding school]. 19989783418
isolation and characterization of salmonella typhimurium and yersinia pseudotuberculosis-containing phagosomes from infected mouse macrophages: y. pseudotuberculosis traffics to terminal lysosomes where they are degraded.the interaction of salmonella and yersinia with macrophages is critical to the pathogenesis of these organisms. after internalization into macrophages, these bacteria reside in membrane-enclosed vacuoles. in this report, we present an approach to isolate and characterize bacteria-containing vacuoles (bcvs) to study intracellular trafficking of pathogenic bacteria within the membrane system of host cells. using the mouse monocyte-macrophage cell line j774a.1, we found that salmonella typhimurium ...19989808287
analysis of the superantigen-producing ability of yersinia pseudotuberculosis strains of various serotypes isolated from patients with systemic or gastroenteric infections, wildlife animals and natural environments.yersinia pseudotuberculosis is a pathogen causing gastroenteritis as well as acute and systemic infections. this organism produces a superantigenic exotoxin, designated y. pseudotuberculosis-derived mitogen (ypm). we consider this exotoxin to be the primary pathogen of the systemic type infection. in this study, we examined 101 y. pseudotuberculosis strains isolated from various sources, patients with the systemic or the gastroenteric type of infections, wildlife animals and natural environments ...19989809408
restriction endonuclease analysis of plasmid dna of yersinia pseudotuberculosis infections in shimane prefecture, japan.the epidemiology of yersinia pseudotuberculosis infections in a limited area of shimane prefecture, japan, was examined by serotyping and restriction endonuclease analysis of virulence plasmid dna of y. pseudotuberculosis strains isolated from humans, wildlife animals and river water. almost all isolates from three sources belonged to serotype 1b reap pattern d and serotype 4b reap patterns b, g and l. the identity of the distribution of serotype and reap patterns among isolates from humans, wil ...19959810674
involvement of focal adhesion kinase in invasin-mediated uptake.high-efficiency entry of the enteropathogenic bacterium yersinia pseudotuberculosis into nonphagocytic cells is mediated by the bacterial outer membrane protein invasin. invasin-mediated uptake requires high affinity binding of invasin to multiple beta1 chain integrin receptors on the host eukaryotic cell. previous studies using inhibitors have indicated that high-efficiency uptake requires tyrosine kinase activity. in this paper we demonstrate a requirement for focal adhesion kinase (fak) for i ...19989811856
characteristics of yersinia pseudotuberculosis isolated from animals in brazil.strains (105) of yersinia pseudotuberculosis isolated in brazil between 1982 and 1990 were bio-serotyped. they were also studied for plasmid profile, autoagglutination and calcium dependence at 37 degrees c, congo red uptake, pyrazinamidase activity, esculin hydrolysis, salicin fermentation and drug sensitivity: 95.24% were biotype 2, serogroup o:3; 2.86% were biotype 1, serogroup o:1; and 1.90% were biotype 2, non-agglutinable. plasmids were found in 77.14% of the strains (one in each strain). ...19989812382
differential effects of integrin alpha chain mutations on invasin and natural ligand interaction.to determine if recognition of the yersinia pseudotuberculosis invasin protein and natural substrates requires identical integrin residues, a region of the human alpha3 integrin chain predicted to be involved in substrate adhesion was targeted for mutation. one point mutation located in a region of the third n-terminal repeat of the alpha3 chain, alpha3-w220a, failed to promote adhesion to the natural alpha3 beta1 substrate epiligrin but maintained near wild type levels of adhesion to invasin. a ...19989822651
[dormant forms of yersinia pseudotuberculosis during interaction with green algae and their exometabolites (population dynamics and ultrastructure)].the dynamics of the transition of y.pseudotuberculosis to the latent (noncultivable) state in sterile soil extraction and in soil extraction, containing scenedesmus algae or their exometabolites, was evaluated by the bacteriological method and with the use of polymerase chain reaction. the formation of y.pseudotuberculosis latent forms achieved its highest rate under the action of algal exometabolites (on day 11), while in the presence of algal cells such formation was delayed to 3-5 months. the ...19989825488
compartmentalization of th1/th2 cytokine responses to experimental yersinia pseudotuberculosis infection in cats.specific pathogen-free cats were inoculated subcutaneously into the drainage areas of the left auricular and popliteal lymph nodes with living yersinia pseudotuberculosis. inflammation was evident at the inoculation sites and the regional lymph nodes were palpably enlarged at 48 h post-infection. lymph node enlargement was due to marked paracortical lymphoid hyperplasia and variable neutrophil infiltrates. yersinia was cultured from the regional lymph nodes and/or spleens of three of the six cat ...19989839869
yersinia-induced apoptosis in vivo aids in the establishment of a systemic infection of mice.pathogenic yersinia cause a systemic infection in mice that is dependent on the presence of a large plasmid encoding a number of secreted virulence proteins called yops. we previously demonstrated that a plasmid-encoded yop, yopj, was essential for inducing apoptosis in cultured macrophages. here we report that yopj is a virulence factor in mice and is important for the establishment of a systemic infection. the oral ld50 for a yopj mutant yersinia pseudotuberculosis increases 64-fold compared w ...19989841926
characterization of cytotoxic factors of yersinia pseudotuberculosis using the mdbk cell line.the cytotoxin of four strains of yersinia pseudotuberculosis was characterized using the mdbk cell line and by application of the mtt colorimetric test. the highest cytotoxin yield was obtained in tryptic soy broth medium after 24 h. it was detected in the cell-free culture filtrate, and treatment of the cells with chaps as a membrane detergent did not decrease significantly their cytotoxic activity. the cytotoxin was inhibited by trypsinization and by increasing values of either acidity or alka ...19989853366
yopj of yersinia spp. is sufficient to cause downregulation of multiple mitogen-activated protein kinases in eukaryotic cells.pathogenic yersinia spp. utilize a plasmid-encoded type iii secretion system to deliver a set of yop effector proteins into eukaryotic cells. previous studies have shown that the effector yopj is required for yersinia to cause downregulation of the mitogen-activated protein (map) kinases c-jun n-terminal kinase (jnk), p38, and extracellular signal-regulated kinase (erk) 1 and 2 in infected macrophages. here we demonstrate that yopj is sufficient to cause downregulation of multiple map kinases in ...19999916081
[effect of the thermostable toxin of yersinia pseudotuberculosis on the oxidant and antioxidant activity of human blood leukocytes].y.pseudotuberculosis thermostable lethal toxin as shown to affect the functional activity of human blood leukocytes. still neutrophils and monocytes exhibited different reaction to the introduction of the toxin. in monocytes, the toxin in a dose of 0.2 microgram/4 x 10(4) cells inhibited the formation of active forms of oxygen (afo) and activated the production of superoxide dismutase (sod). in neutrophils, the toxin affected only the activity of glutathione reductase, inducing a decrease in its ...19989949493
[interactions between bacteria of the genus yersinia in a water environment].under the conditions of a prolonged experiment in sterile water at 4-6 degrees with no outside supply of any substances pathogenic y.pseudotuberculosis, y.enterocolitica and other yersinia species in pure and binary cultures remained viable for the period of 12-24 months (the term of observation). in monocultures, all yersinia actually returned to their initial amounts. in associations with y.enterocolitica o:3, y.frederiksenii and y.intermedia, a delay in the lag-phase (1-2 weeks) was observed ...19989949496
independent acquisition and insertion into different chromosomal locations of the same pathogenicity island in yersinia pestis and yersinia pseudotuberculosis.we show that yersinia pestis and pesticin-sensitive isolates of y. pseudotuberculosis possess a common 34 kbp dna region that has all the hallmarks of a pathogenicity island and is inserted into different asparaginyl trna genes at different chromosomal locations in each species. this pathogenicity island (yp-hpi) is marked by is100, has a g + c content different from its host, is flanked by 24 bp direct repeats, encodes a putative, p4-like integrase and contains the iron uptake virulence genes f ...19999987130
the high-pathogenicity island of yersinia pseudotuberculosis can be inserted into any of the three chromosomal asn trna genes.pathogenicity islands (pais) have been identified in several bacterial species. a pai called high-pathogenicity island (hpi) and carrying genes involved in iron acquisition (yersiniabactin system) has been previously identified in yersinia enterocolitica and yersinia pestis. in this study, the hpi of the third species of yersinia pathogenic for humans, y. pseudotuberculosis, has been characterized. we demonstrate that the hpi of strain ip32637 has a physical and genetic map identical to that of ...19989988474
expression of the plague plasminogen activator in yersinia pseudotuberculosis and escherichia coli.enteropathogenic yersiniae (yersinia pseudotuberculosis and yersinia enterocolitica) typically cause chronic disease as opposed to the closely related yersinia pestis, the causative agent of bubonic plague. it is established that this difference reflects, in part, carriage by y. pestis of a unique 9.6-kb pesticin or pst plasmid (ppcp) encoding plasminogen activator (pla) rather than distinctions between shared approximately 70-kb low-calcium-response, or lcr, plasmids (pcd in y. pestis and pyv i ...199910024583
yersinia pseudotuberculosis bacteremia and splenic abscess in a patient with non-insulin-dependent diabetes mellitus. 199910063398
a region of the yersinia pseudotuberculosis invasin protein enhances integrin-mediated uptake into mammalian cells and promotes self-association.invasin allows efficient entry into mammalian cells by yersinia pseudotuberculosis. it has been shown that the c-terminal 192 amino acids of invasin are essential for binding of beta1 integrin receptors and subsequent uptake. by analyzing the internalization of latex beads coated with invasin derivatives, an additional domain of invasin was shown to be required for efficient bacterial internalization. a monomeric derivative encompassing the c-terminal 197 amino acids was inefficient at promoting ...199910064587
coordinate involvement of invasin and yop proteins in a yersinia pseudotuberculosis-specific class i-restricted cytotoxic t cell-mediated response.yersinia pseudotuberculosis is a pathogenic enteric bacteria that evades host cellular immune response and resides extracellularly in vivo. nevertheless, an important contribution of t cells to defense against yersinia has been previously established. in this study we demonstrate that lewis rats infected with virulent strains of y. pseudotuberculosis, mount a yersinia-specific, rt1-a-restricted, cd8+ t cell-mediated, cytotoxic response. sensitization of lymphoblast target cells for cytolysis by ...199910072536
generated single point-mutations can considerably dismantle the lymphocyte overstimulation induced by yersinia pseudotuberculosis superantigen.the superantigenic yersinia pseudotuberculosis-derived mitogen (ypm) may contribute to severe complications in y. pseudotuberculosis infections. since the pathogenic mechanism of a superantigen (sag) is based on its capability for t-cell overstimulation, by introducing point mutations into ypm an attempt was made to abrogate this effect. six mutants studied exhibited a variety of t-cell proliferating responses. two had activity reduced by 80-90%, three had activity reduced by approximately 50%, ...199910087177
[yersinia enteritis]. 199910088454
[yersinia pseudotuberculosis infection]. 199910088455
analysis of the yersinia enterocolitica 0:8 v antigen for cross protectivity.the plasmid encoded v antigen (vag) of pathogenic yersinia spp. is a major virulence factor as well as a protective immunogen. recently, two main types of vag, represented by either yersinia enterocolitica 0:8 or yersinia pseudotuberculosis, have been identified and it has been suggested, that antibodies generated against one type are unable to protect against yersinia spp. carrying the other type. by using a recombinant vag (rvaghis) of the y. enterocolitica 0:8 type we show here, that actively ...199910089162
a complex composed of sycn and yscb functions as a specific chaperone for yopn in yersinia pestis.human pathogenic yersinia resist host defences, in part through the expression and delivery of a set of plasmid-encoded virulence proteins termed yops. a number of these yops are exported from the bacteria directly into the cytoplasm of their eukaryotic host's cells upon contact with these cells. the secreted yopn protein (also known as lcre) is required to block yop secretion in the presence of calcium in vitro or before contact with a eukaryotic cell in vivo. in this study, we characterize the ...199810094626
[prophylaxis of the experimental pseudotuberculosis infection by immunization with porin from yersinia pseudotuberculosis]. 199910095962
effects of growth temperature and pvm82 plasmid on fatty acids of lipid a from yersinia pseudotuberculosis.effects of cultivation temperature (8 or 37 degrees c) and plasmid profile on the lipid a fatty acids of three isogenic yersinia pseudotuberculosis strains (plasmidless (82-) and strains containing pvm82 (82+) or p57 (57+) plasmids) obtained by alkaline hydrolysis of the whole bacterial cells and differentiated from fatty acids of other membrane lipids were investigated. on the basis of the analysis, it is concluded that lipids a of all studied samples contain 3-hydroxytetradecanoic and dodecano ...199910205304
yersinia pseudotuberculosis-induced calcium signaling in neutrophils is blocked by the virulence effector yoph.pathogenic species of the genus yersinia evade the bactericidal functions of phagocytes. this evasion is mediated through their virulence effectors, yops, which act within target cells. in this study we investigated the effect of yersinia pseudotuberculosis on ca2+ signaling in polymorphonuclear neutrophils. the intracellular free calcium concentration in single adherent human neutrophils was monitored during bacterial infection and, in parallel, the encounter between the bacteria and cells was ...199910225922
[an experimental study of the effects of pectin substances on nonspecific defenses of the body].effects of water-soluble alimentary fibers on nonspecific defense system attracted the attention of scientists in recent decade. effects of some pectins on the phagocytic activity of macrophagal population infected with yersinia pseudotuberculosis is studied on wistar rats. the number of peritoneal exudative cells (test system) and macrophagal activity increased (as shown by increased glycolysis and acid phosphatase activity), while the number of surviving bacteria decreased 1000 times. comparis ...199910234925
molecular characterization of katy (antigen 5), a thermoregulated chromosomally encoded catalase-peroxidase of yersinia pestis.the first temperature-dependent proteins (expressed at 37 degrees c, but not 26 degrees c) to be identified in yersinia pestis were antigens 3 (fraction 1), 4 (ph 6 antigen), and 5 (hereafter termed katy). antigens 3 and 4 are now established virulence factors, whereas little is known about katy, except that it is encoded chromosomally, produced in abundance, possesses modest catalase activity, and is shared by yersinia pseudotuberculosis, but not yersinia enterocolitica. we report here an impro ...199910322012
[yersinia pseudotuberculosis infection]. 199910337751
development of digoxigenin-labeled pcr amplicon probes for use in the detection and identification of enteropathogenic yersinia and shiga toxin-producing escherichia coli from foods.by including digoxigenin-11-dutp in a polymerase chain reaction (pcr), amplification products were produced that contained nonisotopic markers for use as dna hybridization probes. because these labeled amplicons encode pathogenic traits for specific foodborne bacteria, they can be used to detect the presence of potentially virulent organisms that may be present in foods. this technology allows the synthesis of a variety of shelf-stable probe reagents for detecting a number of foodborne microbes ...199910340661
the fate of yersinia pseudotuberculosis lipopolysaccharide (lps) in intraperitoneally and intraarticularly infected rats.persistence and in vivo effects of yersinia pseudotuberculosis serotype iii lps (prepared from bacteria grown at 25 degrees and 37 degrees c) in rats were investigated after intraperitoneal and intraarticular injection during the 30 day period of examination. localization and persistence of lps in the peritoneal and synovial cavities were demonstrated by using the immunofluorescence technique. peritoneal and synovial exudative cell infiltration as well as changes in some parameters (glycolytic a ...199910360314
the v-antigen of yersinia is surface exposed before target cell contact and involved in virulence protein translocation.type iii-mediated translocation of yop effectors is an essential virulence mechanism of pathogenic yersinia. lcrv is the only protein secreted by the type iii secretion system that induces protective immunity. lcrv also plays a significant role in the regulation of yop expression and secretion. the role of lcrv in the virulence process has, however, remained elusive on account of its pleiotropic effects. here, we show that anti-lcrv antibodies can block the delivery of yop effectors into the tar ...199910361299
yersiniabactin from yersinia pestis: biochemical characterization of the siderophore and its role in iron transport and regulation.a siderophore-dependent iron transport system of the pathogenic yersiniae plays a role in the pathogenesis of these organisms. the structure of the yersiniabactin (ybt) siderophore produced by yersinia enterocolitica has been elucidated. this paper reports the purification of ybt from yersinia pestis and demonstrates that it has the same structure as ybt from y. enterocolitica. purified ybt had a formation constant for fe3+ of approximately 4x10(-36). addition of purified ybt from y. pestis enha ...199910376834
the exopolygalacturonate lyase pelw and the oligogalacturonate lyase ogl, two cytoplasmic enzymes of pectin catabolism in erwinia chrysanthemi 3937.erwinia chrysanthemi 3937 secretes into the external medium several pectinolytic enzymes, among which are eight isoenzymes of the endo-cleaving pectate lyases: pela, pelb, pelc, peld, and pele (family 1); peli (family 4); pell (family 3); and pelz (family 5). in addition, one exo-cleaving pectate lyase, pelx (family 3), has been found in the periplasm of e. chrysanthemi. the e. chrysanthemi 3937 gene kdgc has been shown to exhibit a high degree of similarity to the genes pely of yersinia pseudot ...199910383957
seroepidemiologic study on the occurrence of antibodies against yersinia enterocolitica and yersinia pseudotuberculosis in urban and rural population of the lublin region (eastern poland).the aim of this study was to assess the seroprevalence of antibodies against yersinia in the rural and urban population and to determine the frequency of particular serotypes of yersinia enterocolitica and yersinia pseudotuberculosis. 472 sera were examined, 257 of rural inhabitants and 215 of urban inhabitants. the survey was carried out by passive hemagglutination test with the antigens of yersinia serotypes considered pathogenic for humans: y. enterocolitica 03, 05, 06, 08, 09 and y. pseudotu ...199910384217
type iii secretion machines and the pathogenesis of enteric infections caused by yersinia and salmonella spp.salmonella and yersinia spp. infect the intestinal tract of humans. although these organisms cause fundamentally different diseases, each pathogen relies on type iii secretion machines to either inject virulence factors into the cytosol of eukaryotic cells or release toxins into the extracellular milieu. type iii secretion machines are composed of many different subunits and export several polypeptides with unique substrate requirements. during salmonella pathogenesis, the type iii machine encod ...199910399078
analysis of functional regions of ypm, a superantigen derived from gram-negative bacteria.the bacterial superantigens, staphylococcal enterotoxins and streptococcal pyrogenic exotoxins, are grouped in a family by the conservation of amino acid sequence and polypeptide folding patterns. in the case of yersinia pseudotuberculosis-derived mitogen (ypm), however, there is no noticeable homology with this family, although many of the in vitro functional features conform to the criteria for a superantigen. to study the mode of action of ypm at the molecular level, we first generated a numb ...199910406939
cytotoxic t-cell-mediated response against yersinia pseudotuberculosis in hla-b27 transgenic rat.yersinia-induced reactive arthritis is highly associated with hla-b27, the role of which in defense against the triggering bacteria remains unclear. the aim of this study was to examine the capacity of rats transgenic for hla-b27 to mount a cytotoxic t-lymphocyte (ctl) response against y. pseudotuberculosis and to determine the influence of the hla-b27 transgene on this response. rats transgenic for hla-b*2705 and human beta(2)-microglobulin of the 21-4l line, which do not spontaneously develop ...199910417137
characterization of is1541-like elements in yersinia enterocolitica and yersinia pseudotuberculosis.we characterized yersinia enterocolitica and yersinia pseudotuberculosis insertion sequences related to insertion sequence 1541, recently identified in yersinia pestis. for each of the two species, two insertion sequence copies were cloned and sequenced. genetic elements from y. pseudotuberculosis were almost identical to insertion sequence 1541, whereas these from y. enterocolitica were less related. phylogenetic analysis of the putative transposases encoded by insertion sequences from the thre ...199910418150
[rapid method of isolation of lipid a from yersinia pseudotuberculosis].the possibility of preparing the lipid a (la) from yersinia pseudotuberculosis serovar ib by the hydrolysis of whole cells instead of the preliminary isolation of lipopolysaccharide (lps) was demonstrated. direct extraction with an organic solvent of the bacterial mass preliminary treated with 10% acetic acid or 1 m hcl was shown to result in a di- (laacoh) or monophosphoryl derivative (lahcl), respectively. these were completely extractable only after treatment with strong hydrolyzing agents. w ...199910422596
interference of eukaryotic signalling pathways by the bacteria yersinia outer protein yopj.upon contact with bacteria, eukaryotic cells activates a slurry of defence mechanisms via distinct signalling transduction pathways. however, some bacteria have evolved strategies to escape or inhibit these host defence systems. we have recently shown that the bacteria yersinia pseudotuberculosis, which encodes the yersinia outer protein (yopj) appears to inhibit the activation of nf-kappab by preventing the phosphorylation of ikappab. in a subsequent series of experiments it has also been shown ...199910424421
the xanthomonas hrp type iii system secretes proteins from plant and mammalian bacterial pathogens.studies of essential pathogenicity determinants in gram-negative bacteria have revealed the conservation of type iii protein secretion systems that allow delivery of virulence factors into host cells from plant and animal pathogens. ten of 21 hrp proteins of the plant pathogen xanthomonas campestris pv. vesicatoria have been suggested to be part of a type iii machinery. here, we report the hrp-dependent secretion of two avirulence proteins, avrbs3 and avrrxv, by x. campestris pv. vesicatoria str ...199910430949
high-frequency reca-dependent and -independent mechanisms of congo red binding mutations in yersinia pestis.yersinia pestis, which causes bubonic and pneumonic plague, forms pigmented red colonies on congo red (cr) dye agar. the hmshfrs genes required for cr binding (crb(+)) are genetically linked to virulence-associated genes encoding a siderophore uptake system. these genes are contained in a 102-kb chromosomal pgm locus that is lost in a high-frequency deletion event, resulting in loss of the crb(+) phenotype. we constructed a reca mutant strain of y. pestis kim10+ (ypra) to test whether the high f ...199910438760
localization of the yersinia ptpase to focal complexes is an important virulence mechanism.the protein tyrosine phosphatase yoph, produced by the pathogen yersinia pseudotuberculosis, is an essential virulence determinant involved in antiphagocytosis. upon infection, yoph is translocated into the target cell, where it recognizes focal complexes. genetic analysis revealed that yoph harbours a region that is responsible for specific localization of this ptpase to focal complexes in hela cells and professional phagocytes. this region is a prerequisite for blocking an immediate-early yers ...199910447891
the 102-kilobase pgm locus of yersinia pestis: sequence analysis and comparison of selected regions among different yersinia pestis and yersinia pseudotuberculosis strains.we report the complete 119,443-bp sequence of the pgm locus from yersinia pestis and its flanking regions. sequence analysis confirms that the 102-kb unstable pgm locus is composed of two distinct parts: the pigmentation segment and a high-pathogenicity island (hpi) which carries virulence genes involved in iron acquisition (yersiniabactin biosynthetic gene cluster). within the hpi, three genes coding for proteins related to phage proteins were uncovered. they are located at both extremities ind ...199910456941
hmst, a protein essential for expression of the haemin storage (hms+) phenotype of yersinia pestis.the haemin storage (hms) phenotype of yersinia pestis has been shown to be involved in the blockage of fleas that is required for the transmission of plague from fleas to mammals. previously, an operon encoding four genes, hmshfrs, that are essential for the temperature-regulated hms+ phenotype has been characterized. here the isolation and characterization of a fifth gene, hmst, that is essential for this phenotype is described. conceptual translation of hmst suggests it encodes a 44.8 kda prot ...199910463178
identification of a new type of invariant v alpha 14+ t cells and responsiveness to a superantigen, yersinia pseudotuberculosis-derived mitogen.we examined the expression of the h4 t cell activation marker in thymic t cell subpopulations and found that tcr-alpha beta+ cd4+ thymic t cells are segregated into three subpopulations based upon h4 levels. thymic t cells with either no or low h4 expression differentiate via the mainstream differentiation pathway in the thymus. h4int thymic t cells, which express a skewed v beta repertoire of v beta 2, -7, and -8 in their tcrs, show the phenotype of nkt cells: cd44high, ly6chigh, nk1.1+, and tc ...199910477573
inhibition of the mitogen-activated protein kinase kinase superfamily by a yersinia effector.the bacterial pathogen yersinia uses a type iii secretion system to inject several virulence factors into target cells. one of the yersinia virulence factors, yopj, was shown to bind directly to the superfamily of mapk (mitogen-activated protein kinase) kinases (mkks) blocking both phosphorylation and subsequent activation of the mkks. these results explain the diverse activities of yopj in inhibiting the extracellular signal-regulated kinase, c-jun amino-terminal kinase, p38, and nuclear factor ...199910489373
[effect of a lipopolysaccharide on the conformational state and functional activity of a yersinia pseudotuberculosis porin].changes in the structure and functional activity of porin, a protein from yersinia pseudotuberculosis, resulting from the removal of lipopolysaccharide (lps) normally bound with the protein were studied. the treatment of lps-containing porin with a 30% sds solution led to an lps-free protein that, according to the sds-page, remained to be a trimer. it was shown by cd and uv spectroscopies and intrinsic protein fluorescence that the removal of lps caused only conformational changes in the porin s ...199910495899
yoph dephosphorylates cas and fyn-binding protein in macrophages.the tyrosine phosphatase yoph is an essential virulence effector of pathogenic yersinia spp. yoph, which is translocated from extracellularly located bacteria into interacting target cells, blocks phagocytosis by professional phagocytes. we show here that immunoprecipitation of yoph from lysates of j774 cells infected with y. pseudotuberculosis expressing an inactive form of yoph resulted in co-precipitation of certain phosphotyrosine proteins. the association between the inactive yoph and phosp ...199910502464
yersinia pseudotuberculosis blocks the phagosomal acidification of b10.a mouse macrophages through the inhibition of vacuolar h(+)-atpase activity.yersinia pseudotuberculosis survived and multiplied in the phagosomes of b10.a mouse peritoneal macrophages. as one of the possible mechanisms for the bacteria's survival in the phagosomes, we demonstrated that live y. pseudotuberculosis inhibited the phagosomal acidification; ph within phagosomes containing the live y. pseudotuberculosis remained at about 6.0, whereas ph within phagosomes containing the dead y. pseudotuberculosis fell to about 4. 5. this ability to inhibit intraphagosomal acidi ...199910502466
a hierarchical quorum-sensing system in yersinia pseudotuberculosis is involved in the regulation of motility and clumping.in cell-free yersinia pseudotuberculosis culture supernatants, we have chemically characterized three n-acyl homoserine lactone (ahl) molecules, n-octanoyl homoserine lactone (c8-hsl), n-(3-oxohexanoyl)homoserine lactone (3-oxo-c6-hsl) and n-hexanoyl homoserine lactone (c6-hsl). we have identified, cloned and sequenced two pairs of luxr/i homologues termed ypsr/i and ytbr/i. in escherichia coli at 37 degrees c, ypsi and ytbi both synthesize c6-hsl, although ypsi is responsible for 3-oxo-c6-hsl a ...199910510240
crystal structure of invasin: a bacterial integrin-binding protein.the yersinia pseudotuberculosis invasin protein promotes bacterial entry by binding to host cell integrins with higher affinity than natural substrates such as fibronectin. the 2.3 angstrom crystal structure of the invasin extracellular region reveals five domains that form a 180 angstrom rod with structural similarities to tandem fibronectin type iii domains. the integrin-binding surfaces of invasin and fibronectin include similarly located key residues, but in the context of different folds an ...199910514372
colonic epithelial physiology is altered in response to the bacterial superantigen yersinia pseudotuberculosis mitogen.because bacteria are implicated in the pathophysiology of gut inflammation, the ability of the superantigen yersinia pseudotuberculosis mitogen (ypm) to alter epithelial ion transport and permeability was examined by two model systems: epithelial (t84) monolayers cocultured with peripheral blood mononuclear cells (pbmc) with or without ypm and colonic segments from ypm-treated mice. ypm immune activation in vitro caused reduced active ion transport responses to the prosecretory agent forskolin ( ...199910515820
ferric enterochelin transport in yersinia enterocolitica: molecular and evolutionary aspects.yersinia enterocolitica is well equipped for siderophore piracy, encompassing the utilization of siderophores such as ferrioxamine, ferrichrome, and ferrienterochelin. in this study, we report on the molecular and functional characterization of the yersinia fep-fes gene cluster orthologous to the escherichia coli ferrienterochelin transport genes (fepa, fepdgc, and fepb) and the esterase gene fes. in vitro transcription-translation analysis identified polypeptides of 30 and 35 kda encoded by fep ...199910515929
trypsin-like proteinase and its endogenous inhibitor from yersinia pseudotuberculosis. biological activity.a trypsin-like proteinase (yptp) and its endogenous inhibitor (ityp) were isolated from the culture filtrate of the pathogenic bacterium yersinia pseudotuberculosis, and their biological activities were studied. yptp was found to be highly toxic for random-bred white mice. under in vitro conditions the proteolytic enzyme destroyed protective proteins of the immune system of the animals--igg, iga, and proteins of the complement system (ciq, c3, and c5)--and, consequently, was a pathogenetic facto ...199910521713
clinical and experimental evidence for persistent yersinia infection in reactive arthritis.the findings of bacterial antigens in the joint and persistent triggering infection elsewhere in the body are thought to be important in the pathogenesis of reactive arthritis (rea). we describe a patient with clinical and laboratory features consistent with this. the initial presentation with erythema nodosum and periarthritis due to infection with yersinia pseudotuberculosis iv was followed 13 months later by recurrent erythema nodosum with joint effusion. at that time, synovial fluid was show ...199910524699
the tir-binding region of enterohaemorrhagic escherichia coli intimin is sufficient to trigger actin condensation after bacterial-induced host cell signalling.enterohaemorrhagic escherichia coli (ehec) has emerged as an important agent of diarrhoeal disease. attachment to host cells, an essential step during intestinal colonization by ehec, is associated with the formation of a highly organized cytoskeletal structure containing filamentous actin, termed an attaching and effacing (a/e) lesion, directly beneath bound bacteria. the outer membrane protein intimin is required for the formation of this structure, as is tir, a bacterial protein that is trans ...199910540286
suppression of t and b lymphocyte activation by a yersinia pseudotuberculosis virulence factor, yoph.the acquired immune responses are crucial to the survival of yersinia-infected animals. mice lacking t cells are sensitive to yersinia infection, and a humoral response to yersinia can be protective. diverse mechanisms for yersinia to impair and evade the host innate immune defense have been suggested, but the effects of yersinia on lymphocytes are not known. here, we demonstrate that after a transient exposure to y. pseudotuberculosis, t and b cells are impaired in their ability to be activated ...199910544205
yersinia enterocolitica and yersinia pseudotuberculosis.yersinia enterocolitica can cause enteritis, right lower-quadrant pain mimicking appendicitis, reactive arthritis, and erythema nodosum. this organism is transmitted through food, animal contact, and contaminated blood products. patients with iron excess are at a higher risk for serious infection. this article describes the history, microbiology, virulence factors, epidemiology, clinical manifestations, diagnosis, and therapy of y. enterocolitica and y. pseudotuberculosis. in addition, the immun ...199910549424
[study of mechanism of the pathogenic bacteria adaptation to the environmental factors]. 199910560060
autotrophic assimilation of co2 and c1-compounds by pathogenic bacteria.we demonstrate for the first time that the pathogenic bacteria yersinia pseudotuberculosis and listeria monocytogenes (pathogens of saprozoonoses) are capable of chemolithoautotrophic assimilation of co2. low temperature is favorable for better absorption of co2 by these bacteria; this is supported by increased enzymatic activity of carbonic anhydrase acting as the supplier of the substrate to the site of carboxylation. data of radioisotopic methods indicate that assimilated labeled carbon of co ...199910561561
yersinia pestis, the cause of plague, is a recently emerged clone of yersinia pseudotuberculosis.plague, one of the most devastating diseases of human history, is caused by yersinia pestis. in this study, we analyzed the population genetic structure of y. pestis and the two other pathogenic yersinia species, y. pseudotuberculosis and y. enterocolitica. fragments of five housekeeping genes and a gene involved in the synthesis of lipopolysaccharide were sequenced from 36 strains representing the global diversity of y. pestis and from 12-13 strains from each of the other species. no sequence d ...199910570195
[yersinia pseudotuberculosis, a rare cause of septicemia]. 199610592627
the pathogenesis of kawasaki disease and superantigens.kawasaki disease (kd) is an acute febrile illness in infants and children with systemic clinical symptoms, including coronary artery aneurysms. findings seen in kd patients such as infiltration of t cells into vascular lesions, elevation of soluble interleukin 2 receptors in serum, an imbalance of t cell subsets, and transient depletion of t cells with cd11/cd18 suggest that the activation of t cells is involved in the pathogenesis of kd. in 1992, an interesting mechanism was proposed in which t ...199910592892
[functional macrophage activity in response to various plasmid variants of yersinia pseudotuberculosis]. 199910599503
[dynamics of the immune response to porin from the outer membrane of yersinia pseudotuberculosis]. 199910599505
increased expression of periplasmic cu,zn superoxide dismutase enhances survival of escherichia coli invasive strains within nonphagocytic cells.we have studied the influence of periplasmic cu,zn superoxide dismutase on the intracellular survival of escherichia coli strains able to invade epithelial cells by the expression of the inv gene from yersinia pseudotuberculosis but unable to multiply intracellularly. intracellular viability assays, confirmed by electron microscopy observations, showed that invasive strains of e. coli engineered to increase cu,zn superoxide dismutase production are much more resistant to intracellular killing th ...200010603365
heterogeneity of lipopolysaccharides from yersinia pseudotuberculosis: chemical characterization of various molecular types.prior studies have shown some unusual changes in the lipopolysaccharides (lpss) from yersinia pseudotuberculosis that occur when the microbe is grown at low temperature; the specific features of these lpss in comparison with the lpss from other enteropathogens may be due to unusual thermal adaptation mechanisms. to gain insight into this question, the chemical composition of y. pseudotuberculosis lps has been determined. the data indicate that two different s-form lps species are produced in "co ...199910611534
the salmonella yopj-homologue avra does not possess yopj-like activity.the yopj protein of yersinia pseudotuberculosis inhibits several eukaryotic signalling pathways that are normally activated in cells following their contact with bacteria. salmonella encodes a protein, avra, that is secreted by the typeiii inv/spa secretion system which is clearly homologous to yopj (56% identical, 87% similarity). since avra and yopjs similarity also encompassed a region of yopj that had previously been shown to be critical for its biological activity, we were interested whethe ...200010644492
the effect of temperature on the interaction of yersinia pseudotuberculosis lipopolysaccharide with chitosan.the mechanism of binding of lipopolysaccharide (lps) from yersinia pseudotuberculosis to low-molecular-weight chitosan was investigated using sedimentation analysis, centrifugation in glycerol and percoll density gradients, and isopicnic centrifugation in cesium chloride. the lps interaction with chitosan was shown to be a multistage process that depended on time and reaction temperature. a stable lps-chitosan complex could be formed only after preliminary incubation of the initial components at ...199910661469
outbreak of yersinia pseudotuberculosis in british columbia--november 1998. 199910726370
ras effector pathway activation by epidermal growth factor is inhibited in vivo by exoenzyme s adp-ribosylation of ras.we have examined the functional consequences of adp-ribosyltransferase modification of ras by the exoenzyme s (exos) protein of pseudomonas aeruginosa. exos has been shown previously to adp-ribosylate a number of proteins, including members of the ras superfamily, which play an essential role in the processes of cell proliferation, differentiation, motility and cell division. hela and nih3t3 cells were infected with exos protein, which was delivered via the type iii secretion system of the heter ...200010727422
[yersinioses in monkeys]. 200010732248
yersiniosis and trace element deficiency in a dairy herd. 200010736681
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