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yersinia pseudotuberculosis effector yopj subverts the nod2/rick/tak1 pathway and activates caspase-1 to induce intestinal barrier dysfunction.yersinia pseudotuberculosis is an enteropathogenic bacteria that disrupts the intestinal barrier and invades its host through gut-associated lymphoid tissue and peyer's patches (pp). we show that the y. pseudotuberculosis effector yopj induces intestinal barrier dysfunction by subverting signaling of the innate immune receptor nod2, a phenotype that can be reversed by pretreating with the nod2 ligand muramyl-dipeptide. yopj, but not the catalytically inactive mutant yopj(c172a), acetylates criti ...201222520462
derivatives of 8-hydroxyquinoline--antibacterial agents that target intra- and extracellular gram-negative pathogens.small molecule screening identified 5-nitro-7-((4-phenylpiperazine-1-yl-)methyl)quinolin-8-ol inp1750 as a putative inhibitor of type iii secretion (t3s) in the gram-negative pathogen yersinia pseudotuberculosis. in this study we report structure-activity relationships for inhibition of t3s and show that the most potent compounds target both the extracellular bacterium y. pseudotuberculosis and the intracellular pathogen chlamydia trachomatis in cell-based infection models.201222525317
invasive escherichia coli vaccines expressing brucella melitensis outer membrane proteins 31 or 16 or periplasmic protein bp26 confer protection in mice challenged with b. melitensis.because of the serious economic and medical consequences of brucellosis, efforts are to prevent infection of domestic animals through vaccines. many disadvantages are associated with the current brucella melitensis rev.1 vaccine prompting development of alternative vaccines and delivery. escherichia coli (dh5α) was engineered to express a plasmid containing the inv gene from yersinia pseudotuberculosis and the hly gene from listeria monocytogenes. these recombinant invasive e. coli expressing b. ...201222546330
interleukin-10 induction is an important virulence function of the yersinia pseudotuberculosis type iii effector yopm.pathogenic yersinia species modulate host immune responses through the activity of a plasmid-encoded type iii secretion system and its associated effector proteins. one effector, yopm, is a leucine-rich-repeat-containing protein that is important for virulence in murine models of yersinia infection. although the mechanism by which yopm promotes virulence is unknown, we previously demonstrated that yopm was required for the induction of high levels of the immunosuppressive cytokine interleukin-10 ...201222547545
yopj-induced caspase-1 activation in yersinia-infected macrophages: independent of apoptosis, linked to necrosis, dispensable for innate host defense.yersinia outer protein j (yopj) is a type iii secretion system (t3ss) effector of pathogenic yersinia (yersinia pestis, yersinia enterocolitica and yersinia pseudotuberculosis) that is secreted into host cells. yopj inhibits survival response pathways in macrophages, causing cell death. allelic variation of yopj is responsible for differential cytotoxicity in yersinia strains. yopj isoforms in y. enterocolitica o:8 (yopp) and y. pestis kim (yopj(kim)) strains have high cytotoxic activity. in add ...201222563435
yersinia pseudotuberculosis disrupts intestinal barrier integrity through hematopoietic tlr-2 signaling.intestinal barrier function requires intricate cooperation between intestinal epithelial cells and immune cells. enteropathogens are able to invade the intestinal lymphoid tissue known as peyer's patches (pps) and disrupt the integrity of the intestinal barrier. however, the underlying molecular mechanisms of this process are poorly understood. in mice infected with yersinia pseudotuberculosis, we found that pp barrier dysfunction is dependent on the yersinia virulence plasmid and the expression ...201222565313
pathogenesis of y. enterocolitica and y. pseudotuberculosis in human yersiniosis.yersiniosis is a food-borne illness that has become more prevalent in recent years due to human transmission via the fecal-oral route and prevalence in farm animals. yersiniosis is primarily caused by yersinia enterocolitica and less frequently by yersinia pseudotuberculosis. infection is usually characterized by a self-limiting acute infection beginning in the intestine and spreading to the mesenteric lymph nodes. however, more serious infections and chronic conditions can also occur, particula ...201122567322
yersinia enterocolitica and yersinia pseudotuberculosis detection in foods.yersinia enterocolitica and y. pseudotuberculosis which can cause yersiniosis in humans and animals are thought to be significant food-borne pathogens and be important as hygiene indicator in food safety. the pathogenic y. enterocolitica serotypes/biotypes are o:3/4 and 3 variant vp negative, o:5, 27/2, o:8/1b, and o:9/2, have been reported worldwide. y. pseudotuberculosis is distributed less widely than y. enterocolitica. isolation methods usually involve selective and recovery enrichment of th ...201122567341
[origin of the plague microbe yersinia pestis: structure of the process of speciation].the origin and evolution of the plague microbe yersinia pestis are considered in the context of propositions of modern darwinism. it was shown that the plague pathogen diverged from the pseudotuberculous microbe yersinia pseudotuberculosis o:1b in the mountain steppe landscapes of central asia in the sartan: 22000-15000 years ago. speciation occurred in the tarbagan (marmota sibirica)--flea (oropsylla silantiewi) parasitic system. the structure of the speciation process included six stages: isol ...201622567866
cluster analysis of host cytokine responses to biodefense pathogens in a whole blood ex vivo exposure model (weem).rapid detection and therapeutic intervention for infectious and emerging diseases is a major scientific goal in biodefense and public health. toward this end, cytokine profiles in human blood were investigated using a human whole blood ex vivo exposure model, called weem.201222607329
the molecular basis of ubiquitin-like protein nedd8 deamidation by the bacterial effector protein cif.the cycle inhibiting factors (cifs) are a family of translocated effector proteins, found in diverse pathogenic bacteria, that interfere with the host cell cycle by catalyzing the deamidation of a specific glutamine residue (gln40) in nedd8 and the related protein ubiquitin. this modification prevents recycling of neddylated cullin-ring ligases, leading to stabilization of various cullin-ring ligase targets, and also prevents polyubiquitin chain formation. here, we report the crystal structures ...201222691497
surface display of n-terminally anchored invasin by lactobacillus plantarum activates nf-κb in monocytes.the probiotic lactic acid bacterium lactobacillus plantarum is a potential delivery vehicle for mucosal vaccines because of its generally regarded as safe (gras) status and ability to persist at the mucosal surfaces of the human intestine. however, the inherent immunogenicity of vaccine antigens is in many cases insufficient to elicit an efficient immune response, implying that additional adjuvants are needed to enhance the antigen immunogenicity. the goal of the present study was to increase th ...201222706054
immune response to diphtheria toxin-mediated depletion complicates the use of the cd11c-dtr(tg) model for studies of bacterial gastrointestinal infections.dendritic cells play an important role in the immune response against pathogens, as they are responsible for the activation and control of both innate and adaptive immune responses. the cd11c-dtr(tg) model, which allows transient elimination of dendritic cells by diphtheria toxin-treatment (dtx), has been extensively used to study the importance of this immune cell during steady-state and infection conditions in mice. infecting dendritic cell-depleted mice orally with yersinia pseudotuberculosis ...201222771374
diversity and adaptive evolution of a major porin gene (ompf) in yersinia pseudotuberculosis. 201222782744
yersinia pseudotuberculosis o iii causes diarrhea in brazilian cattle. 201222782752
bacteriophages capable of lysing yersinia pestis and yersinia pseudotuberculosis: efficiency of plating tests and identification of receptors in escherichia coli k-12. 201222782755
cytotoxic necrotizing factor is an effective immunogen in a yersinia pseudotuberculosis aerosol mouse model. 201222782762
yop effector proteins from yersinia pseudotuberculosis impair dendritic cell activation. 201222782764
virulence of yersinia pseudotuberculosis in aerosol models. 201222782766
variability in the functional domains of the rho-modifying toxins of yersinia pseudotuberculosis. 201222782772
regulation of virulence gene expression by regulatory rna elements in yersinia pseudotuberculosis. 201222782778
small molecule screening for inhibitors of the yoph phosphatase of yersinia pseudotuberculosis. 201222782782
[yersinia pseudotuberculosis mutant ompf porins with deletions of the external loops: genetic constructions design, expression, isolation and refolding].yersinia pseudotuberculosis outer membrane (om) recombinant mutant ompf porins with deletions of the external loops l1, l6 and l8 were obtained using site-directed mutagenesis of the recombinant plasmid including ompf gene. heterologeous expression of the mutant proteins was carried out in strain rosetta of escherichia coli (novagen, usa), porins with the deletions were isolated from the inclusion bodies. mutant proteins in oligomeric form were obtained as result of dialysis and ion-exchange chr ...201222792719
evolution and virulence contributions of the autotransporter proteins yapj and yapk of yersinia pestis co92 and their homologs in y. pseudotuberculosis ip32953.yersinia pestis, the causative agent of plague, evolved from the gastrointestinal pathogen yersinia pseudotuberculosis. both species have numerous type va autotransporters, most of which appear to be highly conserved. in y. pestis co92, the autotransporter genes yapk and yapj share a high level of sequence identity. by comparing yapk and yapj to three homologous genes in y. pseudotuberculosis ip32953 (yptb0365, yptb3285, and yptb3286), we show that yapk is conserved in y. pseudotuberculosis, whi ...201222802344
creation of a producent, optimization of expression, and purification of recombinant yersinia pseudotuberculosis l-asparaginase.recombinant e. coli strain producing y. pseudotuberculosis q66cj2 (ypa) l-asparaginase ii was created. gene ansb homologue encoding y. pseudotuberculosis ip 32953 l-asparaginase precursor was synthesized. the gene was cloned in pbad24 expression vector and expressed in e. coli bl21 (de3) strain. optimal conditions for the producer strain culturing were selected. an effective method for isolation and purification of the enzyme by two-staged column chromatography was developed.201122808465
[effect of volatile metabolites from germinating seeds on the reproduction of the bacteria listeria monocytogenes and yersinia pseudotuberculosis].the biological activity of volatile metabolites of germinating seeds of cabbage (brassica oleacia), carrot (daukus carota), salad (lactuca sativa), and corn (zea mays l.) against listeria monocytogenes and yersinia pseudotuberculosis was studied. it was shown that volatile metabolites are transfer factors and can be the sole carbon and energy source for these bacteria. methanol is the main substance affecting their growth and reproduction.201522834302
elevated cpxr~p levels repress the ysc-yop type iii secretion system of yersinia pseudotuberculosis.one way that gram-negative bacteria respond to extracytoplasmic stress is through the cpxa-cpxr system. an activated cpxa sensor kinase phosphorylates the cpxr response regulator to instigate positive auto-amplification of cpx pathway activation, as well as synthesis of various bacterial survival factors. in the absence of cpxa, human enteropathogenic yersinia pseudotuberculosis accumulates high cpxr~p levels aided by the action of low molecular weight phosphodonors such as acetyl~p. critically, ...201522842077
hemophagocytic macrophages in murine typhoid fever have an anti-inflammatory phenotype.histiocytes are white blood cells of the monocytic lineage and include macrophages and dendritic cells. in patients with a variety of infectious and noninfectious inflammatory disorders, histiocytes can engulf nonapoptotic leukocytes and nonsenescent erythrocytes and thus become hemophagocytes. we report here the identification and characterization of splenic hemophagocytes in a natural model of murine typhoid fever. the development of a flow-cytometric method allowed us to identify hemophagocyt ...201222868497
identification of mrtab, an abc transporter specifically required for yersinia pseudotuberculosis to colonize the mesenteric lymph nodes.a highly conserved virulence plasmid encoding a type iii secretion system is shared by the three yersinia species most pathogenic for mammals. although factors encoded on this plasmid enhance the ability of yersinia to thrive in their mammalian hosts, the loss of this virulence plasmid does not eliminate growth or survival in host organs. most notably, yields of viable plasmid-deficient yersinia pseudotuberculosis (yptb) are indistinguishable from wild-type yptb within mesenteric lymph nodes. to ...201222876175
yersinia pestis versus yersinia pseudotuberculosis: effects on host macrophages.yersinia pestis, the causative agent of plague, is proved to be a recently emerged clone from y. pseudotuberculosis. however, the diseases they cause and their patterns of transmission are very different. people always focus on the genetic changes between y. pestis and y. pseudotuberculosis to reveal their pathogenic differences, and little is known about host defence differences to these two yersinia. in this study, the effects of y. pestis and y. pseudotuberculosis on macrophages were analysed ...201222882408
abortion in small ruminants in the netherlands between 2006 and 2011.during five successive lambing seasons between 2006 and 2011, 453 submissions of abortion material, 282 of ovine and 171 of caprine origin, were examined at the animal health service in the netherlands. infectious agents as the most plausible cause of the abortion were found in 48 percent of the ovine submissions and in 34 percent of the caprine submissions. submission of both aborted fetus and placental membranes increased the diagnostic yield of laboratory investigations (17 percent and 21 per ...201222900421
coiled-coils in the yopd translocator family: a predicted structure unique to the yopd n-terminus contributes to full virulence of yersinia pseudotuberculosis.pathogenic yersinia all harbor a virulence plasmid-encoded ysc-yop t3ss. in this system, translocator function is performed by the hydrophobic proteins yopb and yopd. with the goal to better understand how yopd orchestrates yop-regulatory control, translocon pore formation and yop effector translocation, we performed an in silico prediction of coiled-coil motifs in yopd and yopd-like sequences from other bacteria. of interest was a predicted n-terminal coiled-coil that occurred solely in yersini ...201222910185
evaluation of a single procedure allowing the isolation of enteropathogenic yersinia along with other bacterial enteropathogens from human stools.enteropathogenic yersinia are among the most frequent agents of human diarrhea in temperate and cold countries. however, the incidence of yersiniosis is largely underestimated because of the peculiar growth characteristics of pathogenic yersinia, which make their isolation from poly-contaminated samples difficult. the use of specific procedures for yersinia isolation is required, but is expensive and time consuming, and therefore is not systematically performed in clinical pathology laboratories ...201222911756
[the new views to pseudotuberculosis pathology].for the first time the nature of cell damages under pseudotuberculosis as a generalized infection has been analyzed by positions of the modern knowledge about types of the cell death. the own and literature data have pointed to presence the apoptosis-induced effect of yersinia pseudotuberculosis, a causative agent of this infection. in conclusion, the typical pathological changes for pseudotuberculosis infection such as granuloma formation with the central karyorrhexis could be appearance of apo ...201222937584
detection and isolation of yersinia pestis without fraction 1 antigen by monoclonal antibody in foods and water.most available immunoassays for yersinia pestis are based on the detection of fraction 1 antigen (f1) when yersiniae are grown at 37°c. a monoclonal antibody (mab) was developed based on the detection of surface antigens that are not f1. f1-deficient y. pestis cells were induced and used to immunize balb/c mice from which mab (immunoglobulin g1), which specifically recognizes y. pestis, with or without f1, was obtained. this mab (6b5) did not cross-react with enteric bacteria, including yersinia ...201222947461
the yersinia pseudotuberculosis outer membrane protein ail recruits the human complement regulatory protein factor h.previous investigations characterizing the mechanism(s) of complement resistance in yersinia pseudotuberculosis showed that the outer membrane protein ail can functionally recruit the regulator of the classical and lectin pathways of complement, c4b-binding protein. in this study, we extend these observations and show that ail can also recruit the regulator of the alternative pathway (ap), factor h (fh). binding to fh was dependent on ail expression and observed in the context of full-length lps ...201222956584
modern advances against plague.plague has been a scourge of humanity, responsible for the deaths of millions. the etiological agent, yersinia pestis, has evolved relatively recently from an enteropathogen, yersinia pseudotuberculosis. the evolution of the plague pathogen has involved a complex series of genetic acquisitions, deletions, and rearrangements in its transition from an enteric niche to becoming a systemic, flea-vectored pathogen. with the advent of modern molecular biology techniques, we are starting to understand ...201222958531
outbreak of yersiniosis in egyptian rousette bats (rousettus aegyptiacus) caused by yersinia pseudotuberculosis serotype 4b.this report describes an outbreak of yersiniosis in egyptian rousette bats (rousettus aegyptiacus) caused by yersinia pseudotuberculosis serotype 4b. twelve of 61 bats died between november and december 2008 or in may 2009. the bats often displayed multiple yellow-white nodules in the spleen and liver. microscopically, these consisted of focal necrosis accompanied by inflammatory cell infiltration and colonies of gram-negative bacilli. the bacterial colonies were identified immunohistochemically ...201322980777
quantification of bacterial indicators and zoonotic pathogens in dairy wastewater ponds.zoonotic pathogens in land-applied dairy wastewaters are a potential health risk. the occurrence and abundance of 10 pathogens and 3 fecal indicators were determined by quantitative real-time pcr (qpcr) in samples from 30 dairy wastewaters from southern idaho. samples tested positive for campylobacter jejuni, stx(1)- and eaea-positive escherichia coli, listeria monocytogenes, mycobacterium avium subsp. paratuberculosis, and salmonella enterica, with mean recoveries of genomic dna corresponding t ...201222983964
interactions of the cpxa sensor kinase and cognate cpxr response regulator from yersinia pseudotuberculosis.the cpxa sensor kinase-cpxr response regulator two-component regulatory system is a sentinel of bacterial envelope integrity. integrating diverse signals, it can alter the expression of a wide array of components that serve to shield the envelope from damage and to promote bacterial survival. in bacterial pathogens such as yersinia pseudotuberculosis, this also extends to pathogenesis. cpxr is thought to dimerize upon phosphorylation by the sensor kinase cpxa. this phosphorylation enables cpxr b ...201223013530
comparative genomic analysis of gene variations of two chinese yersinia pestis isolates from vaccine strain ev76.to investigate genomic variations of two chinese yersinia pestis isolates that were isolated from different plague foci obtained from vaccine strain ev76 from the yunnan province of china.201223026524
a novel high-resolution melting analysis-based method for yersinia pseudotuberculosis genotyping.yersinia pseudotuberculosis is an enteric pathogen that is environmentally widespread and is known to cause human and animal infections. the development of a fast and inexpensive typing system is necessary to facilitate epidemiological studies of y. pseudotuberculosis infections. in this study, we aimed to develop a method of y. pseudotuberculosis genotyping based on determining differences in single-nucleotide polymorphisms (snps) using a high-resolution melting analysis (hrma). using a set of ...201223041267
establishment of a health surveillance program for reintroduction of the eurasian beaver (castor fiber) into scotland.in 2009 and 2010 16 norwegian eurasian beavers (castor fiber) were reintroduced to knapdale, scotland as part of a 5-yr reintroduction trial (scottish beaver trial). despite numerous reintroduction programs throughout europe there is no published information concerning recommended health surveillance during beaver reintroduction and only one publication describing causes of mortality. we describe the establishment of a health surveillance program based on international union of conservation of n ...201223060498
the o-specific polysaccharide structure and gene cluster of serotype o:12 of the yersinia pseudotuberculosis complex, and the identification of a novel l-quinovose biosynthesis gene.a major virulence factor for yersinia pseudotuberculosis is lipopolysaccharide, including o-polysaccharide (ops). currently, the ops based serotyping scheme for y. pseudotuberculosis includes 21 known o-serotypes, with genetic and structural data available for 17 of them. the completion of the ops structures and genetics of this species will enable the visualization of relationships between o-serotypes and allow for analysis of the evolutionary processes within the species that give rise to new ...201323077132
the yersinia pseudotuberculosis degradosome is required for oxidative stress, while its pnpase subunit plays a degradosome-independent role in cold growth.yersinia polynucleotide phosphorylase (pnpase), a 3'-5' exoribonuclease, has been shown to affect growth during several stress responses. in escherichia coli, pnpase is one of the subunits of a multiprotein complex known as the degradosome, but also has degradosome-independent functions. the carboxy-terminus of e. coli ribonuclease e (rnase e) serves as the scaffold upon which pnpase, enolase (a glycolytic enzyme), and rhlb helicase all have been shown to bind. in the yersiniae, only pnpase has ...201223082859
role of yopk in yersinia pseudotuberculosis resistance against polymorphonuclear leukocyte defense.the enteropathogen yersinia pseudotuberculosis can survive in the harsh environment of lymphoid compartments that abounds in immune cells. this capacity is dependent on the plasmid-encoded yersinia outer proteins (yops) that are delivered into the host cell via a mechanism involving the yersinia type iii secretion system. we show that the virulence protein yopk has a role in the mechanism by which y. pseudotuberculosis avoids the polymorphonuclear leukocyte or neutrophil (pmn) defense. a yopk mu ...201323090955
a type vi secretion system regulated by ompr in yersinia pseudotuberculosis functions to maintain intracellular ph homeostasis.type vi secretion systems (t6sss) which widely distributed in gram-negative bacteria have been primarily studied in the context of cell interactions with eukaryotic hosts or other bacteria. we have recently identified a thermoregulated t6ss4 in the enteric pathogen yersinia pseudotuberculosis. here we report that ompr directly binds to the promoter of t6ss4 operon and regulates its expression. further, we observed that the ompr-regulated t6ss4 is essential for bacterial survival under acidic con ...201323094603
prevalence and genetic diversity of enteropathogenic yersinia spp. in pigs at farms and slaughter in lithuania.the prevalence of enteropathogenic yersinia spp. in pigs at farms and slaughter in relation to potential farming risk factors in lithuania was examined. pig faeces and carcase swab samples from 11 farms were studied at slaughterhouses. nine of the 11 farms were visited again 3-5 months later, and pooled feacal samples and environmental samples were collected. pathogenic yersinia enterocolitica was found in 64% and yersinia pseudotuberculosis in 45% of the sampled pig farms. all obtained isolates ...201323102547
a multi-omic systems approach to elucidating yersinia virulence mechanisms.the underlying mechanisms that lead to dramatic differences between closely related pathogens are not always readily apparent. for example, the genomes of yersinia pestis (yp) the causative agent of plague with a high mortality rate and yersinia pseudotuberculosis (ypt) an enteric pathogen with a modest mortality rate are highly similar with some species specific differences; however the molecular causes of their distinct clinical outcomes remain poorly understood. in this study, a temporal mult ...201323147219
assignment and secondary structure of the yada membrane protein by solid-state mas nmr.we report the complete solid-state mas nmr resonance assignment of a medium-sized, trimeric membrane protein, yada-m. the protein yada (yersinia adhesin a) is an important virulence factor of enteropathogenic yersinia species (such as yersinia enterocolitica and yersinia pseudotuberculosis). yada is localized on the bacterial cell surface and is involved in adhesion to host cells and tissues. it is anchored in the outer membrane by a transmembrane anchor domain (yada-m). this domain hosts the so ...201223150774
sequencing of virulence genes shows limited genetic variability in yersinia pseudotuberculosis.yersinia pseudotuberculosis is a foodborne pathogen often detected and identified using polymerase chain reaction (pcr) with primers targeted to virulence genes. sequence variability of the virulence genes in strains representing different serotypes is unknown. sequence variability could hinder the recognition of this pathogen by pcr and affect the host-pathogen interactions. sequencing of inv, virf, and yada of 18 y. pseudotuberculosis strains showed limited variability of inv and virf, whereas ...201323153288
molecular cloning, isolation, and properties of chaperone skp from yersinia pseudotuberculosis.the skp gene of yersinia pseudotuberculosis was expressed without its signal sequence in escherichia coli bl21(de3) cells. the recombinant protein skp accumulated in soluble form in the cytoplasm of the producer strain. the protein was isolated and characterized: the molecular weight, isoelectric point, n-terminal amino acid sequence (20 amino acid residues), and the content of the secondary structure elements were determined. using cross-linking stabilization and high-mass maldi-tof mass spectr ...201223240570
a conjugative 38 kb plasmid is present in multiple subspecies of xylella fastidiosa.a ≈ 38kb plasmid (pxf-riv5) was present in the riv5 strain of xylella fastidiosa subsp. multiplex isolated from ornamental plum in southern california. the complete nucleotide sequence of pxf-riv5 is almost identical to that of pxfas01 from x. fastidiosa subsp. fastidiosa strain m23; the two plasmids vary at only 6 nucleotide positions. blast searches and phylogenetic analyses indicate pxf-riv5 and pxfas01 share some similarity to chromosomal and plasmid (pxf51) sequences of x. fastidiosa subsp. ...201223251694
crp induces switching of the csrb and csrc rnas in yersinia pseudotuberculosis and links nutritional status to virulence.colonization of the intestinal tract and dissemination into deeper tissues by the enteric pathogen yersinia pseudotuberculosis demands expression of a special set of virulence factors important for the initiation and the persistence of the infection. in this study we demonstrate that many virulence-associated functions are coregulated with the carbohydrate metabolism. this link is mediated by the carbon storage regulator (csr) system, including the regulatory rnas csrb and csrc, and the camp rec ...201223251905
structure and function of cytidine monophosphate kinase from yersinia pseudotuberculosis, essential for virulence but not for survival.the need for new antibiotics has become pressing in light of the emergence of antibiotic-resistant strains of human pathogens. yersinia pestis, the causative agent of plague, is a public health threat and also an agent of concern in biodefence. it is a recently emerged clonal derivative of the enteric pathogen yersinia pseudotuberculosis. previously, we developed a bioinformatic approach to identify proteins that may be suitable targets for antimicrobial therapy and in particular for the treatme ...201223271832
acute encephalopathy and tubulointerstitial nephritis associated with yersinia pseudotuberculosis.we report the case of a 28-month-old boy with encephalopathy and acute tubulointerstitial nephritis possibly associated with yersinia pseudotuberculosis (yp) infection. he was transferred to our center because of impairment of renal function and altered consciousness. he had fever for 5 days after recurrent vomiting and diarrhea. computed tomography scan was normal, but electroencephalogram (eeg) analyses showed generalized slow wave patterns. continuous hemodialysis was undergone and then his r ...201223279023
impact of host membrane pore formation by the yersinia pseudotuberculosis type iii secretion system on the macrophage innate immune response.type iii secretion systems (t3sss) are used by gram-negative pathogens to form pores in host membranes and deliver virulence-associated effector proteins inside host cells. in pathogenic yersinia, the t3ss pore-forming proteins are yopb and yopd. mammalian cells recognize the yersinia t3ss, leading to a host response that includes secretion of the inflammatory cytokine interleukin-1β (il-1β), toll-like receptor (tlr)-independent expression of the stress-associated transcription factor egr1 and t ...201323297383
yersinia infection tools-characterization of structure and function of adhesins.among the seventeen species of the gram-negative genus yersinia, three have been shown to be virulent and pathogenic to humans and animals-y. enterocolitica, y. pseudotuberculosis, and y. pestis. in order to be so, they are armoured with various factors that help them adhere to tissues and organelles, cross the cellular barrier and escape the immune system during host invasion. the group of proteins that mediate pathogen-host interactions constitute adhesins. invasin, ail, yada, yadb, yadc, pla, ...201223316485
identification and characterization of small rnas in yersinia pestis.yersinia pestis, the etiologic agent of plague, is closely related to yersinia pseudotuberculosis evolutionarily but has a very different mode of infection. the rna-binding regulatory protein, hfq, mediates regulation by small rnas (srnas) and is required for virulence of both y. pestis and y. pseudotuberculosis. moreover, hfq is required for growth of y. pestis, but not y. pseudotuberculosis, at 37°c. together, these observations suggest that srnas play important roles in the virulence and surv ...201323324607
inheritance of the lysozyme inhibitor ivy was an important evolutionary step by yersinia pestis to avoid the host innate immune response.yersinia pestis (the plague bacillus) and its ancestor, yersinia pseudotuberculosis (which causes self-limited bowel disease), encode putative homologues of the periplasmic lysozyme inhibitor ivy and the membrane-bound lysozyme inhibitor mlic. the involvement of both inhibitors in virulence remains subject to debate.201323402825
application of chromosomal dna and protein targeting for the identification of yersinia pestis.a comprehensive strategy was developed and validated for the identification of pathogens from closely related near neighbors using both chromosomal and protein biomarkers, with emphasis on distinguishing yersinia pestis from the ancestral bacterium yersinia pseudotuberculosis.201323436733
counting small rna in pathogenic bacteria.here, we present a modification to single-molecule fluorescence in situ hybridization that enables quantitative detection and analysis of small rna (srna) expressed in bacteria. we show that short (~200 nucleotide) nucleic acid targets can be detected when the background of unbound singly dye-labeled dna oligomers is reduced through hybridization with a set of complementary dna oligomers labeled with a fluorescence quencher. by neutralizing the fluorescence from unbound probes, we were able to s ...201323577771
draft genome sequences of five yersinia pseudotuberculosis st19 isolates and one isolate variant.we report the first draft genome sequences of five yersinia pseudotuberculosis isolates of sequence type (st) 19 and of a variant from one of the five isolates. the total length of assemblies ranged from 4,226,485 bp to 4,274,148 bp, including between 3,808 and 3,843 predicted coding sequences.201323580708
demarcating sura activities required for outer membrane targeting of yersinia pseudotuberculosis adhesins.sura is a periplasmic protein folding factor involved in chaperoning and trafficking of outer membrane proteins across the gram-negative bacterial periplasm. in addition, sura also possesses peptidyl-prolyl cis/trans isomerase activity. we have previously reported that in enteropathogenic yersinia pseudotuberculosis, sura is needed for bacterial virulence and envelope integrity. in this study, we investigated the role of sura in the assembly of important yersinia adhesins. using genetic mutation ...201323589578
proteolytic processing of the yersinia pestis yapg autotransporter by the omptin protease pla and the contribution of yapg to murine plague pathogenesis.autotransporter protein secretion represents one of the simplest forms of secretion across gram-negative bacterial membranes. once secreted, autotransporter proteins either remain tethered to the bacterial surface or are released following proteolytic cleavage. autotransporters possess a diverse array of virulence-associated functions such as motility, cytotoxicity, adherence and autoaggregation. to better understand the role of autotransporters in disease, our research focused on the autotransp ...201323657527
solution of the problem of nonspecific binding in solid-phase noninstrumental dot immunoassay.in this work, we evaluated blocking properties of various reagents used in dot immunoassay test systems on nitrocellulose membranes employing carbon-based diagnosticum to determine antibodies to tetanus anatoxin, thermostable toxin of yersinia pseudotuberculosis, and hiv-i. the results support the usage of a nonionic detergent tween 20 which efficiently inhibited nonspecific protein binding to the solid-phase reagent surface and did not decrease sensitivity of the analysis.201323657647
[physicochemical properties and antiproliferative activity of recombinant yersinia pseudotuberculosis l-asparaginase].the physicochemical, catalytic, and antiproliferative activity of a recombinant l-asparaginase from yersinia pseudotuberculosis (ypa) have been studied. the following results were obtained: the k(m) value for l-asparagine is 17 +/- 0.9 microm, the optimal temperature is 60 degrees c, ph is 8.0, pi is 5.4 +/- 0.3, the l-glutaminase activity is no more than 5-6% of the l-asparaginase activity, and the antiproliferative activity on the fisher l5178y lymphadenosis cell line comprised t/c = 136% (p < ...201323662446
physiological levels of glucose induce membrane vesicle secretion and affect the lipid and protein composition of yersinia pestis cell surfaces.yersinia pestis grown with physiologic glucose increased cell autoaggregation and deposition of extracellular material, including membrane vesicles. membranes were characterized, and glucose had significant effects on protein, lipid, and carbohydrate profiles. these effects were independent of temperature and the biofilm-related locus pgm and were not observed in yersinia pseudotuberculosis.201323686263
expression and cytoprotective activity of the small gtpase rhob induced by the escherichia coli cytotoxic necrotizing factor 1.rhob is the only member of the rho subfamily of small gtpases, which is classified as an immediate early gene product. rhob is up-regulated in response to growth factors as well as cytotoxic and genotoxic agents. clostridial glucosylating toxins have been reported to evoke pronounced rhob expression, based on the inactivation of rho/ras proteins. in this study, we report on a long lasting expression of rhob in cultured cells upon activation of rho proteins by the cytotoxic necrotizing factor 1 ( ...201323732113
effect of phenol-induced changes in lipid composition on conformation of ompf-like porin of yersinia pseudotuberculosis.the present work aimed to compare the effects of different lysophosphatidylethanolamine (lpe) content in lipids derived from yersinia pseudotuberculosis cells exposed and not exposed to phenol on the conformation of ompf-like porin of these bacteria. differential scanning calorimetry and intrinsic protein fluorescence showed that the 2.5-fold increase of lpe content and the corresponding increase in the phase transition temperature of bacterial lipids were accompanied by enhanced protein thermos ...201323742936
the pyv virulence plasmids of yersinia pseudotuberculosis and y. pestis contain a conserved dna region responsible for the mobilization by the self-transmissible plasmid pye854.pathogenic yersinia strains possess a 70 kb virulence plasmid which can be transmitted to other strains by conjugation systems expressed by co-resident plasmids. we isolated a 720 bp fragment of the yersinia pseudotuberculosis virulence plasmid p1340 that mediated mobilization of the vector piv2 by the self-transmissible plasmid pye854. the p1340 mobilization region contains the resolvase gene tnpr and its proposed resolution site res. both elements are required for mobilization. plasmid transfe ...201223760829
caspase-11 activation in response to bacterial secretion systems that access the host cytosol.inflammasome activation is important for antimicrobial defense because it induces cell death and regulates the secretion of il-1 family cytokines, which play a critical role in inflammatory responses. the inflammasome activates caspase-1 to process and secrete il-1β. however, the mechanisms governing il-1α release are less clear. recently, a non-canonical inflammasome was described that activates caspase-11 and mediates pyroptosis and release of il-1α and il-1β. caspase-11 activation in response ...201323762026
human single-chain urokinase is activated by the omptins pgte of salmonella enterica and pla of yersinia pestis despite mutations of active site residues.fibrinolysis is important in cell migration and tightly regulated by specific inhibitors and activators; of the latter, urokinase (upa) associates with enhancement of cell migration. active upa is formed through cleavage of the single-chain upa (scupa). the salmonella enterica strain 14028r cleaved human scupa at the peptide bond lys158-ile159, the site cleaved also by the physiological activator human plasmin. the cleavage led to activation of scupa, while no cleavage or activation were detecte ...201323763588
patterning bacterial communities on epithelial cells.micropatterning of bacteria using aqueous two phase system (atps) enables the localized culture and formation of physically separated bacterial communities on human epithelial cell sheets. this method was used to compare the effects of escherichia coli strain mg1655 and an isogenic invasive counterpart that expresses the invasin (inv) gene from yersinia pseudotuberculosis on the underlying epithelial cell layer. large portions of the cell layer beneath the invasive strain were killed or detached ...201323785519
adhesins and host serum factors drive yop translocation by yersinia into professional phagocytes during animal infection.yersinia delivers yops into numerous types of cultured cells, but predominantly into professional phagocytes and b cells during animal infection. the basis for this cellular tropism during animal infection is not understood. this work demonstrates that efficient and specific yop translocation into phagocytes by yersinia pseudotuberculosis (yptb) is a multi-factorial process requiring several adhesins and host complement. when wt yptb or a multiple adhesin mutant strain, δailδinvδyada, colonized ...201323818844
microbiological quality of fresh-cut carrots and process waters.fresh vegetables may be contaminated by pathogens in different ways after harvest. pathogenic microorganisms associated with fresh vegetables can cause severe outbreaks of foodborne disease. we discuss here the results of microbiological analysis of carrot samples, as well as of washing, processing, and wastewater samples. washed, unpeeled carrots generally contained the highest aerobic plate counts (mean, 5.5 log cfu/g). escherichia coli was not detected in any carrot or water sample examined. ...201323834799
expression of a yersinia pseudotuberculosis type vi secretion system is responsive to envelope stresses through the ompr transcriptional activator.the type vi secretion system (t6ss) is a macromolecular complex widespread in gram-negative bacteria. although several t6ss are required for virulence towards host models, most are necessary to eliminate competitor bacteria. other functions, such as resistance to amoeba predation, biofilm formation or adaptation to environmental conditions have also been reported. this multitude of functions is reflected by the large repertoire of regulatory mechanisms shown to control t6ss expression, productio ...201323840509
high frequency of reactive arthritis in adults after yersinia pseudotuberculosis o:1 outbreak caused by contaminated grated carrots.we describe the epidemiological and microbiological process in the clearing of a foodborne outbreak of yersinia pseudotuberculosis o:1 linked to raw carrots and frequency of the associated reactive extra-gastrointestinal manifestations.201423852698
draft genome sequences of two yersinia pseudotuberculosis st43 (o:1b) strains, b-7194 and b-7195.we report the first draft genome sequences of two yersinia pseudotuberculosis sequence type 43 (st43) (o:1b) strains, b-7194 and b-7195, isolated in russia. the total lengths of the assemblies are 4,427,121 bp and 4,608,472 bp, and 3,819 and 4,018 coding sequences, respectively, were predicted within the genomes.201323868131
alternative sigma factor σe has an important role in stress tolerance of yersinia pseudotuberculosis ip32953.yersinia pseudotuberculosis is an important pathogen that probably survives well in the modern food chain. however, little is known about the mechanisms that allow the growth of this pathogen in foods under stress conditions. the expression of rpoe encoding σ(e) was defined by quantitative real-time reverse transcription-pcr. expression of rpoe was induced at 3°c, 37°c, and 42°c, under exposure to 3% nacl, 3% ethanol, or high and low ph, in relation to its expression at the optimum growth temper ...201323872565
proposed reclassification of pasteurella lymphangitidis sneath & stevens 1990 as yersinia pseudotuberculosis.the 16s rrna gene sequences of pasteurella lymphangitidis, yersinia pseudotuberculosis and yersinia pestis were found to be identical and multilocus sequence analysis could not discriminate between the three species. the susceptibility to a y. pseudotuberculosis phage and the presence of the y. pseudotuberculosis-specific invasin gene in p. lymphangitidis indicate that the latter should be reclassified as y. pseudotuberculosis.201323919959
difficulties in diagnosing terminal ileitis due to yersinia pseudotuberculosis.we report three patients with terminal ileitis and positive fecal cultures with yersinia pseudotuberculosis. from one patient, a virulence plasmid (pyv)-negative y. pseudotuberculosis was isolated, which represents the second finding of a pyv-negative isolate associated with human disease. all patients were treated with ciprofloxacin and fully recovered. since conventional culture methods for yersiniosis are gradually replaced with molecular tests not recognizing y. pseudotuberculosis, we recomm ...201423925588
fatal atypical o:3 yersinia pseudotuberculosis infection in cynomolgus macaques.fatal yersinia pseudotuberculosis infection in cynomolgus macaques was diagnosed based upon pathology, microbiology and pcr for this study. pathological findings included acute, erosive to ulcerative, necrohemorrhagic enterocolitis. genotyping by pcr showed an o:3 pattern (gmd-fcl(+), ddhc-prt(+), manb(+), ddha-b(+)), but an additional gene, wbyk, was detected. this is the second report to identify wbyk+ o:3 genotype as the cause of fatal yersiniosis. the first case was reported in 2008, and inv ...201323932075
flis modulates flgm activity by acting as a non-canonical chaperone to control late flagellar gene expression, motility and biofilm formation in yersinia pseudotuberculosis.the flgm-flia regulatory circuit plays a central role in coordinating bacterial flagellar assembly. in this study, we identified multiple novel binding partners of flgm using bacterial two-hybrid screening. among these binding partners, flis, the secretion chaperone of the filament protein flic, was identified to compete with flia for the binding of flgm. we further showed that by binding to flgm, flis protects it from secretion and degradation, thus maintaining an intracellular pool of flgm res ...201423957589
nonenzymatic test system for noninstrumental determination of antibodies to species-specific fibers of yersinia pseudotuberculosis on the basis of nanosized carbon particles. 201323975407
molecular analysis of a novel toll/interleukin-1 receptor (tir)-domain containing virulence protein of y. pseudotuberculosis among far east scarlet-like fever serotype i strains.pathogenicity of yersinia pseudotuberculosis is determined by an arsenal of virulence factors. particularly, the yersinia outer proteins (yops) and the type iii secretion system (t3ss) encoded on the pyv virulence plasmid are required for yersinia pathogenicity. a specific group of y. pseudotuberculosis, responsible for the clinical syndrome described as far east scarlet-like fever (feslf), is known to have an altered virulence gene cluster. far east strains cause unique clinical symptoms for wh ...201324018301
genotyping of outbreak-associated and sporadic yersinia pseudotuberculosis strains by novel multilocus variable-number tandem repeat analysis (mlva).yersinia pseudotuberculosis human infections caused by serotype o:1 and o:3 isolates have been common in finland and have also caused outbreaks. epidemiological studies on the outbreaks have been limited by the lack of accurate typing methods. during the recent years, multilocus variable-number tandem repeat analysis (mlva) has been successfully applied for molecular typing of several bacterial pathogens. we designed an mlva scheme based on seven loci for y. pseudotuberculosis. the method was ab ...201324050949
genetically engineered frameshifted yopn-tyea chimeras influence type iii secretion system function in yersinia pseudotuberculosis.type iii secretion is a tightly controlled virulence mechanism utilized by many gram negative bacteria to colonize their eukaryotic hosts. to infect their host, human pathogenic yersinia spp. translocate protein toxins into the host cell cytosol through a preassembled ysc-yop type iii secretion device. several of the ysc-yop components are known for their roles in controlling substrate secretion and translocation. particularly important in this role is the yopn and tyea heterodimer. in this stud ...201324098594
yersinia pseudotuberculosis uses ail and yada to circumvent neutrophils by directing yop translocation during lung infection.a yersinia pseudotuberculosis (yptb) murine model of lung infection was previously developed using the serotype iii ip2666ndei strain, which robustly colonized lungs but only sporadically disseminated to the spleen and liver. we demonstrate here that a serotype ib yptb strain, ip32953, colonizes the lungs at higher levels and disseminates more efficiently to the spleen and liver compared with ip2666ndei . the role of adhesins was investigated during ip32953 lung infection by constructing isogeni ...201424119087
homology analysis of pathogenic yersinia species yersinia enterocolitica, yersinia pseudotuberculosis, and yersinia pestis based on multilocus sequence typing.we developed a multilocus sequence typing (mlst) scheme and used it to study the population structure and evolutionary relationships of three pathogenic yersinia species. mlst of these three yersinia species showed a complex of two clusters, one composed of yersinia pseudotuberculosis and yersinia pestis and the other composed of yersinia enterocolitica. within the first cluster, the predominant y. pestis sequence type 90 (st90) was linked to y. pseudotuberculosis st43 by one locus difference, a ...201424131695
the wzy o-antigen polymerase of yersinia pseudotuberculosis o:2a has a dependence on the wzz chain-length determinant for efficient polymerization.lipopolysaccharide is a major immunogenic structure for the pathogen yersinia pseudotuberculosis, which contains the o-specific polysaccharide (ops) that is presented on the cell surface. the ops contains many repeats of the oligosaccharide o-unit and exhibits a preferred modal chain length that has been shown to be crucial for cell protection in yersinia. it is well established that the wzz protein determines the preferred chain length of the ops, and in its absence, the polymerization of o uni ...201324164168
customizable pcr-microplate array for differential identification of multiple pathogens.customizable pcr-microplate arrays were developed for the rapid identification of salmonella typhimurium, salmonella saintpaul, salmonella typhi, shigella dysenteriae, escherichia coli o157:h7, francisella tularensis subsp. tularensis, francisella tularensis subsp. novicida, vibrio cholerae, vibrio parahaemolyticus, yersinia pestis, and yersinia pseudotuberculosis. previously, we identified highly specific primers targeting each of these pathogens. here, we report the development of customizable ...201324215700
temperature-dependence of yadbc phenotypes in yersinia pestis.yadb and yadc are putative trimeric autotransporters present only in the plague bacterium yersinia pestis and its evolutionary predecessor, yersinia pseudotuberculosis. previously, yadbc was found to promote invasion of epithelioid cells by y. pestis grown at 37 °c. in this study, we found that yadbc also promotes uptake of 37 °c-grown y. pestis by mouse monocyte/macrophage cells. we tested whether yadbc might be required for lethality of the systemic stage of plague in which the bacteria would ...201424222617
the cytotoxic necrotizing factor of yersinia pseudotuberculosis (cnfy) enhances inflammation and yop delivery during infection by activation of rho gtpases.some isolates of yersinia pseudotuberculosis produce the cytotoxic necrotizing factor (cnfy), but the functional consequences of this toxin for host-pathogen interactions during the infection are unknown. in the present study we show that cnfy has a strong influence on virulence. we demonstrate that the cnfy toxin is thermo-regulated and highly expressed in all colonized lymphatic tissues and organs of orally infected mice. most strikingly, we found that a cnfy knock-out variant of a naturally t ...201324244167
a type iii secretion system inhibitor targets yopd while revealing differential regulation of secretion in calcium-blind mutants of yersinia pestis.numerous gram-negative pathogens rely upon type iii secretion (t3s) systems to cause disease. several small-molecule inhibitors of the type iii secretion systems have been identified; however, few targets of these inhibitors have been elucidated. here we report that 2,2'-thiobis-(4-methylphenol) (compound d), inhibits type iii secretion in yersinia pestis, yersinia pseudotuberculosis, and pseudomonas aeruginosa. yopd, a protein involved in the formation of the translocon and regulatory processes ...201424247143
an nf-κb-based high-throughput screen identifies piericidins as inhibitors of the yersinia pseudotuberculosis type iii secretion system.the type iii secretion system (t3ss) is a bacterial appendage used by dozens of gram-negative pathogens to subvert host defenses and cause disease, making it an ideal target for pathogen-specific antimicrobials. here, we report the discovery and initial characterization of two related natural products with t3ss-inhibitory activity that were derived from a marine actinobacterium. bacterial extracts containing piericidin a1 and the piericidin derivative mer-a 2026b inhibited yersinia pseudotubercu ...201424295981
molecular typing of yersinia pseudotuberculosis strains isolated from livestock in brazil.yersinia pseudotuberculosis can infect a broad range of animals. in brazil, this bacterium has been isolated from healthy and sick animals from sporadic cases and outbreaks of hemorrhagic gastroenteritis among livestock. however, the molecular diversity of these isolates is little understood. in this study, we used multilocus sequence typing, enterobacterial repetitive intergenic consensus pcr and pulsed-field gel electrophoresis to genotype 40 y. pseudotuberculosis strains belonging to bio-sero ...201324301748
the resveratrol tetramer (-)-hopeaphenol inhibits type iii secretion in the gram-negative pathogens yersinia pseudotuberculosis and pseudomonas aeruginosa.society faces huge challenges, as a large number of bacteria have developed resistance towards many or all of the antibiotics currently available. novel strategies that can help solve this problem are urgently needed. one such strategy is to target bacterial virulence, the ability to cause disease e.g., by inhibition of type iii secretion systems (t3sss) utilized by many clinically relevant gram-negative pathogens. many of the antibiotics used today originate from natural sources. in contrast, m ...201324324737
bioluminescent tracking of colonization and clearance dynamics of plasmid-deficient yersinia pestis strains in a mouse model of septicemic plague.yersinia pestis 201 contains 4 plasmids ppcp1, pmt1, pcd1 and pcry, but little is known about the effects of these plasmids on the dissemination of y. pestis. we developed a plasmid-based luxcdabe bioreporter in y. pestis 201, y. pestis 201-pcd1(+), y. pestis 201-pmt1(+), y. pestis 201-ppcp1(+), y. pestis 201-pcry(+), y. pestis 201-p(-) and yersinia pseudotuberculosis pa36060 strains, and investigated their dissemination by bioluminescence imaging during primary septicemic plague in a mouse mode ...201424333143
[the bacteriophages yersinia pseudotuberculosis: the detection in strains of different o-serovars and their identification].the sample included five indicator pseudotuberculosis strains. the application of these strains permitted to isolate out of 161 strains of y. pseudotuberculosis 9 bacteriophages identical by their morphologic and serologic characteristics but having individual particularities in their lytic activity. the test on sensitivity to bacteriophages can be used in laboratory diagnostic to differentiate the strains of yersinia pseudotuberculosis.201324340749
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