Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| use of a chitin synthesis inhibitor to control fleas on wild rodents important in the maintenance of plague, yersinia pestis, in california. | a study was designed to test the insect development inhibitors fluazuron and lufenuron for the control of fleas on sylvatic rodents as an adjunct to the control of plague. historical data of flea burden from 15 prior years of study at chuchupate campground, ventura county, ca, were compared to six years of treatment period data to determine if fluazuron and lufenuron were effective in controlling flea densities. the insect development inhibitors, delivered systemically via a feed cube, reduced f ... | 2008 | 19263847 |
| protective immunity in mice achieved with dry powder formulation and alternative delivery of plague f1-v vaccine. | the potential use of yersinia pestis as a bioterror agent is a great concern. development of a stable powder vaccine against y. pestis and administration of the vaccine by minimally invasive methods could provide an alternative to the traditional liquid formulation and intramuscular injection. we evaluated a spray-freeze-dried powder vaccine containing a recombinant f1-v fusion protein of y. pestis for vaccination against plaque in a mouse model. mice were immunized with reconstituted spray-free ... | 2009 | 19261773 |
| comparative functional analysis of the rcsc sensor kinase from different enterobacteriaceae. | the rcs phosphorelay is an important signalling pathway that is conserved throughout the enterobacteriaceae. the rcs phosphorelay is composed of the rcsc sensor kinase, a membrane-localized hpt-containing protein rcsd and the cytoplasmic response regulator rcsb. in this study we were interested in studying the degree of functional conservation between the different enteric rcsc homologues. therefore, we tested for the ability of rcsc homologues from pathogenic escherichia coli, salmonella enteri ... | 2009 | 19260968 |
| nsom- and afm-based nanotechnology elucidates nano-structural and atomic-force features of a y. pestis v immunogen-containing particle vaccine capable of eliciting robust response. | it is postulated that unique nanoscale proteomic features of immunogen on vaccine particles may determine immunogen-packing density, stability, specificity, and ph-sensitivity on the vaccine particle surface and thus impact the vaccine-elicited immune responses. to test this presumption, we employed near-filed scanning optical microscopy (nsom)- and atomic force microscopy (afm)-based nanotechnology to study nano-structural and single-molecule force bases of yersinia pestis (y. pestis) v immunog ... | 2009 | 19253301 |
| transcription factor function and promoter architecture govern the evolution of bacterial regulons. | evolutionary changes in ancestral regulatory circuits can bring about phenotypic differences between related organisms. studies of regulatory circuits in eukaryotes suggest that these modifications result primarily from changes in cis-regulatory elements (as opposed to alterations in the transcription factors that act upon these sequences). it is presently unclear how the evolution of gene regulatory circuits has proceeded in bacteria, given the rampant effects of horizontal gene transfer, which ... | 2009 | 19251636 |
| exogenous yersinia pestis quorum sensing molecules n-octanoyl-homoserine lactone and n-(3-oxooctanoyl)-homoserine lactone regulate the lcrv virulence factor. | lcrv is a key yersinia pestis antigen, immune regulator, and component of the type iii secretion system (t3ss). researchers have shown that n-acyl-homoserine lactones (ahls) can down-regulate the expression of the lcrv homolog, pcrv, in pseudomonas aeruginosa. using elisa, western blot, dna microarray analysis, and real time pcr we demonstrate that the addition of ahl molecules n-octanoyl-homoserine lactone (c8) or n-(3-oxooctanoyl)-homoserine lactone (oxo-c8) to y. pestis cultures down-regulate ... | 2009 | 19249344 |
| vapour-phase hydrogen peroxide inactivates yersinia pestis dried on polymers, steel, and glass surfaces. | this study evaluated the inactivation of virulent yersinia pestis dried on polymers, steel, and glass surfaces using vapour-phase hydrogen peroxide. | 2008 | 19241520 |
| curing of four different plasmids in yersinia pestis using plasmid incompatibility. | plasmids are critical for the pathogenicity of yersinia pestis. in order to carry out a systematic investigation of their role in pathogenesis, we cured plasmids from y. pestis. | 2008 | 19241516 |
| immobilization of his-tagged proteins on nickel-chelating nanolipoprotein particles. | nanolipoprotein particles (nlps) are nanometer-sized, discoidal particles that self-assemble from purified apolipoprotein and phospholipid. their size and facile functionalization suggest potential application of nlps as platforms for the presentation and delivery of recombinant proteins. to this end, we investigated incorporation of nickel-chelating lipids into nlps (ninlps) and subsequent sequestration of polyhistidine (his)-tagged proteins. from initial lipid screens for nlp formation, the tw ... | 2009 | 19239247 |
| investigation of yersinia pestis in xenopsylla astia. | in this study, at the department of parasitology in the pasteur institute of iran, xenopsylla were allowed to feed on mice infected with yersinia pestis. after 24-48 hours, they were killed by ether and kept in alcohol (70%) for 20 minutes. they were then examined for pathological signs and bacilli in different tissues and organs, longitudinally and cross-sectionally. the samples were studied using conjugated antibody and fluorescence microscopy. the results of this study revealed that the bacil ... | 2003 | 19238669 |
| yersinia pestis is1541 transposition provides for escape from plague immunity. | yersinia pestis is perhaps the most feared infectious agent due to its ability to cause epidemic outbreaks of plague disease in animals and humans with high mortality. plague infections elicit strong humoral immune responses against the capsular antigen (fraction 1 [f1]) of y. pestis, and f1-specific antibodies provide protective immunity. here we asked whether y. pestis generates mutations that enable bacterial escape from protective immunity and isolated a variant with an is1541 insertion in c ... | 2009 | 19237527 |
| integral and peripheral association of proteins and protein complexes with yersinia pestis inner and outer membranes. | yersinia pestis proteins were sequentially extracted from crude membranes with a high salt buffer (2.5 m nabr), an alkaline solution (180 mm na2co3, ph 11.3) and membrane denaturants (8 m urea, 2 m thiourea and 1% amidosulfobetaine-14). separation of proteins by 2d gel electrophoresis was followed by identification of more than 600 gene products by ms. data from differential 2d gel display experiments, comparing protein abundances in cytoplasmic, periplasmic and all three membrane fractions, wer ... | 2009 | 19228400 |
| characterization of new substrates targeted by yersinia tyrosine phosphatase yoph. | yoph is an exceptionally active tyrosine phosphatase that is essential for virulence of yersinia pestis, the bacterium causing plague. yoph breaks down signal transduction mechanisms in immune cells and inhibits the immune response. only a few substrates for yoph have been characterized so far, for instance p130cas and fyb, but in view of yoph potency and the great number of proteins involved in signalling pathways it is quite likely that more proteins are substrates of this phosphatase. in this ... | 2009 | 19221593 |
| production and characterization of monoclonal antibodies against yopm effector protein of yersinia pestis. | the yopm is an essential virulence effector produced by the bubonic plague bacterium. yersinia pestis specific pcr gene was developed using 780 bp fragment of yopm gene. the pcr product was further cloned (in puc57) an subcloned (pqe32 expression vector) and transformed in sg13009 e. coli host cells. the iptg-induced recombinant protein was expressed at approximately 32 kda region by sds-page. the recombinant protein was with 80% purity and 3mg/ml of concentration. polyclonal and monoclonal anti ... | 2009 | 19207012 |
| inactivation of yersinia pseudotuberculosis 197 and francisella tularensis lvs in beverages by high pressure processing. | in 2003, the u.s. department of health and human services announced a new research program to develop technologies and strategies to prevent and minimize potential food safety and security threats. the threat of terrorist attacks against the nation's food supplies has created the need to study microorganisms not typically associated with foodborne illness. high-pressure processing has been proposed as a treatment to reduce yersinia pestis and francisella tularensis lvs levels in beverages. the o ... | 2009 | 19205479 |
| temperature and growth phase influence the outer-membrane proteome and the expression of a type vi secretion system in yersinia pestis. | yersinia pestis cells were grown in vitro at 26 and 37 degrees c, the ambient temperatures of its flea vector and its mammalian hosts, respectively, and subjected to subcellular fractionation. abundance changes at 26 vs 37 degrees c were observed for many outer-membrane (om) proteins. the cell adhesion protein ail (y1324) and three putative small beta-barrel om proteins (y1795, y2167 and y4083) were strongly increased at 37 degrees c. the ail/lom family protein y1682 (ompx) was strongly increase ... | 2009 | 19202098 |
| a single component two-valent lcrv-f1 vaccine protects non-human primates against pneumonic plague. | yersinia pestis continues to pose a threat as a potential biological weapon and is recognized by public health experts as a re-emerging infectious disease. therefore there is great interest in developing a safe and effective vaccine. vaccines against plague containing both the fraction 1 (f1) and v antigens of y. pestis have shown promise in protecting animal models against pneumonic plague, the deadliest form of the disease. here we report on a plague vaccine consisting of the f1 and lcrv antig ... | 2009 | 19200825 |
| [search for primers on the basis of yersinia pestis chromosomal dna for effective pcr identification of typical and atypical plague pathogen strains]. | the authors present the results of a comparative appraisal of a set of species-specific primers in the polymerase chain reaction (pcr) identification of typical and atypical plague pathogen strains. a hundred and seventy-three strains with a species specificity of y. pestis and 67 heterologous strains were used to appraise the well-known y. pestis chromosomal dna-based primers: "3a", "yp2769ms06", "vlml2for/isrev216", "vlm33/isfor1754", as well as "js" specific to y. pseudotuberculosis". in some ... | 2008 | 19198278 |
| evaluation of ultrafiltration cartridges for a water sampling apparatus. | to determine the efficiency of various ultrafiltration cartridges (ufc) in concentrating test micro-organisms from drinking water. | 2009 | 19191977 |
| yersinia pestis and host macrophages: immunodeficiency of mouse macrophages induced by yscw. | the virulence of the pathogenic yersinia species depends on a plasmid-encoded type iii secretion system (t3ss) that transfers six yersinia outer protein (yop) effector proteins into the cytoplasm of eukaryotic cells, leading to disruption of host defence mechanisms. it is shown in this study that yersinia pestis yscw, a protein of the t3ss injectisome, contributes to the induction of a deficiency in phagocytosis in host macrophages and a reduction in their antigen-presenting capacity. a y. pesti ... | 2009 | 19191914 |
| different pathologies but equal levels of responsiveness to the recombinant f1 and v antigen vaccine and ciprofloxacin in a murine model of plague caused by small- and large-particle aerosols. | presently there is a significant effort to develop and evaluate vaccines and antibiotics against the potential bioterrorism agent yersinia pestis. the animal models used to test these countermeasures involve the deposition of small particles within the lung. however, deliberate aerosol release of y. pestis will generate both small and large inhalable particles. we report in this study that the pathogenesis patterns of plague infections caused by the deposition of 1- and 12-microm-particle aeroso ... | 2009 | 19188359 |
| plague in the prairie. | 2009 | 19186696 | |
| [modulating effect of serotonin on the development of human leukocytes apoptosis induced by yersinia]. | effect of biogenic amine serotonin on the development of human blood leukocytes during interaction with species from yersinia genus (y. pestis ev, y. pseudotuberculosis serovars i and iv, y. enterocolitica serovars 09 and 03) was studied in model system in vitro using flow cytofluorometry. serotonin in concentration 10(-5) m had differently marked effects on yersinia spp.-induced apoptosis of leukocytes. pattern of the observed changes depended from species and serovar of yersinia. serotonin inh ... | 2008 | 19186545 |
| atomic resolution structure of the cytoplasmic domain of yersinia pestis yscu, a regulatory switch involved in type iii secretion. | crystal structures of cleaved and uncleaved forms of the yscu cytoplasmic domain, an essential component of the type iii secretion system (t3ss) in yersinia pestis, have been solved by single-wavelength anomolous dispersion and refined with x-ray diffraction data extending up to atomic resolution (1.13 a). these crystallographic studies provide structural insights into the conformational changes induced upon auto-cleavage of the cytoplasmic domain of yscu. the structures indicate that the cleave ... | 2009 | 19165725 |
| pneumonic plague pathogenesis and immunity in brown norway rats. | the brown norway rat was recently described as a bubonic plague model that closely mimics human disease. we therefore evaluated the brown norway rat as an alternative small animal model for pneumonic plague and characterized both the efficacy and potency of vaccine candidates. when infected by intranasal instillation, these rats rapidly developed fatal pneumonic plague within 2 to 4 days of infection. plague disease was characterized by severe alveolar edema and vascular hemorrhage in the lung i ... | 2009 | 19164505 |
| real-time multiplex pcr assay for detection of yersinia pestis and yersinia pseudotuberculosis. | a multiplex real-time polymerase chain reaction (pcr) assay was developed for the detection of yersinia pestis and yersinia pseudotuberculosis. the assay includes four primer pairs, two of which are specific for y. pestis, one for y. pestis and y. pseudotuberculosis and one for bacteriophage lambda; the latter was used as an internal amplification control. the y. pestis-specific target genes in the assay were ypo2088, a gene coding for a putative methyltransferase, and the pla gene coding for th ... | 2009 | 19161535 |
| mucosally delivered salmonella typhi expressing the yersinia pestis f1 antigen elicits mucosal and systemic immunity early in life and primes the neonatal immune system for a vigorous anamnestic response to parenteral f1 boost. | neonates respond poorly to conventional vaccines. this has been attributed, in part, to the immaturity of neonatal dendritic cells that lack full capacity for ag presentation and t cell stimulation. we engineered an attenuated salmonella typhi strain to express and export the f1 ag of y. pestis (s. typhi(f1)) and investigated its immunogenicity early in life using a heterologous prime-boost regimen. newborn mice primed intranasally with a single dose of s. typhi(f1) elicited mucosal ab- and ifn- ... | 2009 | 19124765 |
| adenovirus-mediated delivery of an anti-v antigen monoclonal antibody protects mice against a lethal yersinia pestis challenge. | pneumonic plague, caused by inhalation of yersinia pestis, represents a major bioterrorism threat for which no vaccine is available. based on the knowledge that genetic delivery of monoclonal antibodies (mabs) with adenovirus (ad) gene transfer vectors results in rapid, high-level antibody expression, we evaluated the hypothesis that ad-mediated delivery of a neutralizing antibody directed against the y. pestis v antigen would protect mice against a y. pestis challenge. mabs specific for the y. ... | 2009 | 19124600 |
| attenuated enzootic (pestoides) isolates of yersinia pestis express active aspartase. | it is established that yersinia pestis, the causative agent of bubonic plague, recently evolved from enteropathogenic yersinia pseudotuberculosis by undergoing chromosomal degeneration while acquiring two unique plasmids that facilitate tissue invasion (ppcp) and dissemination by fleabite (pmt). thereafter, plague bacilli spread from central asia to sylvatic foci throughout the world. these epidemic isolates exhibit a broad host range including man as opposed to enzootic (pestoides) variants tha ... | 2009 | 19118360 |
| biophysical characterization and formulation of f1-v, a recombinant plague antigen. | the recombinant plague antigen, f1-v, was studied for its structural characteristics using several biophysical techniques. a larger apparent molecular weight relative to its calculated molecular weight obtained from size exclusion chromatography, an unusually large r(g) obtained from mals, and ans dye binding studies which indicate that all hydrophobic regions of the protein are exposed to solvent demonstrated that f1-v exists like a disordered protein with a worm-like conformation. the ph-solub ... | 2009 | 19116945 |
| extensive antibody cross-reactivity among infectious gram-negative bacteria revealed by proteome microarray analysis. | antibodies provide a sensitive indicator of proteins displayed by bacteria during sepsis. because signals produced by infection are naturally amplified during the antibody response, host immunity can be used to identify biomarkers for proteins that are present at levels currently below detectable limits. we developed a microarray comprising approximately 70% of the 4066 proteins contained within the yersinia pestis proteome to identify antibody biomarkers distinguishing plague from infections ca ... | 2009 | 19112181 |
| gene expression profiling of yersinia pestis with deletion of lcrg, a known negative regulator for yop secretion of type iii secretion system. | yersinia pestis injects a set of virulent proteins into the cytosol of eukaryotic cells by a type iii secretion system (t3ss). lcrg is a known negative regulator for secretion of yersinia outer-membrane proteins (yops) by blocking the secretion apparatus (ysc) from the inner membrane. to further understand the effect of lcrg deletion on y. pestis t3ss regulation, transcriptional profiles from the deltalcrg mutant and wild-type y. pestis strains were compared. the results showed that although the ... | 2009 | 19109068 |
| the yersinia pestis caf1m1a1 fimbrial capsule operon promotes transmission by flea bite in a mouse model of bubonic plague. | plague is a zoonosis transmitted by fleas and caused by the gram-negative bacterium yersinia pestis. during infection, the plasmidic caf1m1a1 operon that encodes the y. pestis f1 protein capsule is highly expressed, and anti-f1 antibodies are protective. surprisingly, the capsule is not required for virulence after injection of cultured bacteria, even though it is an antiphagocytic factor and capsule-deficient y. pestis strains are rarely isolated. we found that a caf-negative y. pestis mutant w ... | 2009 | 19103769 |
| intracellular pathogenic bacteria and fungi--a case of convergent evolution? | the bacterium yersinia pestis and the fungus cryptococcus neoformans are the causative agents of human plague and cryptococcosis, respectively. both microorganisms are facultatively intracellular pathogens. a comparison of their pathogenic strategies reveals similar tactics for intracellular survival in y. pestis and c. neoformans despite their genetic unrelatedness. both organisms can survive in environments where they are vulnerable to predation by amoeboid protozoal hosts. here, we propose th ... | 2009 | 19098923 |
| the subcutaneous inoculation of ph 6 antigen mutants of yersinia pestis does not affect virulence and immune response in mice. | two isogenic sets of yersinia pestis strains were generated, composed of wild-type strains 231 and i-1996, their non-polar ph 6(-) mutants with deletions in the psaa gene that codes for its structural subunit or the whole operon, as well as strains with restored ability for temperature- and ph-dependent synthesis of adhesion pili or constitutive production of ph 6 antigen. the mutants were generated by site-directed mutagenesis of the psa operon and subsequent complementation in trans. it was sh ... | 2009 | 19074650 |
| characterization of the rat pneumonic plague model: infection kinetics following aerosolization of yersinia pestis co92. | yersinia pestis, the causative agent of human bubonic and pneumonic plague, is spread during natural infection by the fleas of rodents. historically associated with infected rat fleas, studies on the kinetics of infection in rats are surprisingly few, and these reports have focused mainly on bubonic plague. although the natural route of primary infection results in bubonic plague in humans, it is commonly thought that aerosolized y. pestis will be utilized during a biowarfare attack. accordingly ... | 2009 | 19073275 |
| the yersinia pestis ail protein mediates binding and yop delivery to host cells required for plague virulence. | although adhesion to host cells is a critical step in the delivery of cytotoxic yop proteins by yersinia pestis, the mechanism has not been defined. to identify adhesins critical for yop delivery, we initiated two transposon mutagenesis screens using the mariner transposon. to avoid redundant cell binding activities, we initiated the screen with a strain deleted for two known adhesins, ph 6 antigen and the autotransporter, yapc, as well as the caf1 capsule, which is known to obscure some adhesin ... | 2009 | 19064637 |
| demonstration of early-phase transmission of yersinia pestis by the mouse flea, aetheca wagneri (siphonaptera: ceratophylidae), and implications for the role of deer mice as enzootic reservoirs. | the role of deer mice and other species of peromyscus as enzootic reservoirs for plague remains controversial. in this study, we evaluated early-phase vector efficiency of aetheca wagneri baker, a common flea species infesting deer mice, to determine the likelihood that y. pestis could be spread mouse to mouse by this species. we showed that a. wagneri could transmit plague bacteria to laboratory mice as early as 3 d postinfection (p.i.), but transmission efficiency was quite low (1.03%; 95% ci: ... | 2008 | 19058643 |
| microarray expression profiling of yersinia pestis in response to berberine. | coptis chinensis franch. is a natural herb widely used in china for prevention and treatment of infectious diseases. plague is a deadly disease caused by yersinia pestis. coptis chinensis franch. is considered the therapeutic agent of choice against plague rather than conventional antibiotics because of its low cost and low toxicity. berberine is the major constituent of a coptis chinensis franch. extract. in the present study, dna microarray was used to investigate the transcription of y. pesti ... | 2009 | 19053015 |
| discrimination between biothreat agents and 'near neighbor' species using a resequencing array. | timely identification of biothreat organisms from large numbers of clinical or environmental samples in potential outbreak or attack scenario is critical for effective diagnosis and treatment. this study aims to evaluate the potential of resequencing arrays for this purpose. albeit suboptimal, this report demonstrated that respiratory pathogen microarray version 1 can identify bacillus anthracis, francisella tularensis, yersinia pestis and distinguish them from benign 'near neighbor' species in ... | 2008 | 19049648 |
| bacterial topoisomerase i as a target for discovery of antibacterial compounds. | bacterial topoisomerase i is a potential target for discovery of new antibacterial compounds. mutant topoisomerases identified by sos induction screening demonstrated that accumulation of the dna cleavage complex formed by type ia topoisomerases is bactericidal. characterization of these mutants of yersinia pestis and escherichia coli topoisomerase i showed that dna religation can be inhibited while maintaining dna cleavage activity by decreasing the binding affinity of mg(ii) ions. this can be ... | 2009 | 19042977 |
| caf1a usher possesses a caf1 subunit-like domain that is crucial for caf1 fibre secretion. | the chaperone/usher pathway controls assembly of fibres of adhesive organelles of gram-negative bacteria. the final steps of fibre assembly and fibre translocation to the cell surface are co-ordinated by the outer membrane proteins, ushers. ushers consist of several soluble periplasmic domains and a single transmembrane beta-barrel. here we report isolation and structural/functional characterization of a novel middle domain of the caf1a usher from yersinia pestis. the isolated umd (usher middle ... | 2009 | 19032149 |
| the response regulator phop negatively regulates yersinia pseudotuberculosis and yersinia pestis biofilms. | a few yersinia pseudotuberculosis strains form biofilms on the head of the nematode caenorhabditis elegans, but numerous others do not. we show that a widely used y. pseudotuberculosis strain, ypiii, is biofilm positive because of a mutation in phop, which encodes the response regulator of a two-component system. for two wild-type y. pseudotuberculosis that do not make biofilms on c. elegans, deletion of phop was sufficient to produce robust biofilms. in yersinia pestis, a phop mutant made more ... | 2009 | 19025559 |
| isolation and confirmation of yersinia pestis mutants exempt from select agent regulations. | this unit describes protocols for yersinia pestis to confirm plasmid profiles, construct and confirm a deltapgm mutation, and cure the low-calcium response (lcr) plasmid encoding a type iii secretion system (ttss). strains lacking either the chromosomal pgm locus or the lcr plasmid can be safely studied under bsl-2 conditions and are exempt from select agent regulations in the u.s. | 2008 | 19016442 |
| laboratory maintenance and characterization of yersinia pestis. | this unit describes protocols for yersinia pestis maintenance and growth in research and clinical laboratories, including some protocols for strain characterization. strain-dependent requirements for different biosafety level containments are also discussed. | 2008 | 19016441 |
| targeting type iii secretion in yersinia pestis. | yersinia pestis, the causative agent of plague, utilizes a plasmid-encoded type iii secretion system (t3ss) to aid it with its resistance to host defenses. this system injects a set of effector proteins known as yops (yersinia outer proteins) into the cytosol of host cells that come into contact with the bacteria. t3ss is absolutely required for the virulence of y. pestis, making it a potential target for new therapeutics. using a novel and simple high-throughput screening method, we examined a ... | 2009 | 19015348 |
| asp-to-asn substitution at the first position of the dxd toprim motif of recombinant bacterial topoisomerase i is extremely lethal to e. coli. | the toprim domain found in many nucleotidyl transferases contains a dxd motif involved in magnesium ion coordination for catalysis. medium- to high-copy-number plasmid clones of yersinia pestis topoisomerase i (yptop) with asp-to-asn substitution at the first aspartate residue (d117n) of this motif could not be generated in escherichia coli without second-site mutation even when expression was under the control of the tightly regulated bad promoter and suppressed by 2% glucose in the medium. ara ... | 2009 | 19013470 |
| [preparation of fractions and characteristic of neutrophilokines complex induced by yersinia pestis ev]. | biochemical and immunobiologic characteristics of fractions of neutrophilokines during primary and secondary immune response against plague infection are presented. fractions were obtained using gel chromatography from neutrophilokines complex induced by vaccine strain of yersinia pestis. it was revealed that fractions of neutrophilokines regulate il-2 synthesis by th1-helpers, il-4 and il-5 synthesis by th2-helpers and also expression of il-2 receptors by immunocompetent cells. helper effect of ... | 2008 | 19006834 |
| [modeling of interaction between yersinia pestis and tetrahymena pyriformis in experimental ecosystems]. | modeling of interaction yersinia pestis-tetrahymena pyriformis in artificial soil ecosystem (ase) containing soil of burrows of main carrier from gorno-altayski natural plague reservoir, as well as in physiological solution (ps) and in hottinger broth (hb). optimal proportion of bacterial and protozoa cells was possible to obtain and depended from virulence of y. pestis and environmental conditions. in ase at 18-22 degrees c association was the most stable under the microbial burden of 100 micro ... | 2008 | 19004283 |
| structure of a shigella effector reveals a new class of ubiquitin ligases. | bacterial pathogens have evolved effector proteins with ubiquitin e3 ligase activities through structural mimicking. here we report the crystal structure of the shigella flexneri type iii effector ipah3, a member of the leucine-rich repeat (lrr)-containing bacterial e3 family. the lrr domain is structurally similar to yersinia pestis yopm and potentially binds to substrates. the structure of the c-terminal e3 domain differs from the typical ring- and hect-type e3s. ipah3 synthesizes a lys48-link ... | 2008 | 18997779 |
| identification of a thermo-regulated glutamine-binding protein from yersinia pestis. | here we present modeling and nmr spectroscopic evidence that the function of a yersinia pestis pmt1 plasmid protein, designated as orf38, is most likely a glutamine binding protein. the modeling was homology-based at a very low level of sequence identity ( approximately 16%) and involved structural comparison of multiple templates, as well as template-substrate interaction analyses. transferred nuclear overhauser and saturation transfer difference experiments were used to characterize the bindin ... | 2008 | 18991762 |
| proteolytic inactivation of tissue factor pathway inhibitor by bacterial omptins. | the immune response to infection includes activation of the blood clotting system, leading to extravascular fibrin deposition to limit the spread of invasive microorganisms. some bacteria have evolved mechanisms to counteract this host response. pla, a member of the omptin family of gram-negative bacterial proteases, promotes the invasiveness of the plague bacterium, yersinia pestis, by activating plasminogen to plasmin to digest fibrin. we now show that the endogenous anticoagulant tissue facto ... | 2009 | 18988866 |
| flagellin-f1-v fusion protein is an effective plague vaccine in mice and two species of nonhuman primates. | a number of studies have clearly demonstrated that flagellin is a potent adjuvant that promotes robust immune responses when it is given with a protein antigen. in view of the potential biological and practical benefits of a recombinant protein vaccine composed of a single fusion protein containing flagellin and antigen, we have evaluated the efficacy of a fusion protein composed of flagellin and two protective antigens of yersinia pestis (f1 and v) in eliciting protection against respiratory ch ... | 2009 | 18987167 |
| serologic survey of the sentinel animals for plague surveillance and screening for complementary diagnostic markers to f1 antigen by protein microarray. | plague is a deadly infectious disease caused by the gram-negative bacterium, yersinia pestis. in 2005, five plague patients were confirmed in the yulong county of the yunnan province, china. in this study, the serologic survey of > 2,900 serum samples from domestic dogs and cats in and around the county, where human plague occurred, confirmed that domestic dogs and cats could serve as sentinel animals for plague surveillance. meanwhile, the antibody responses in the infected dogs and cats were p ... | 2008 | 18981526 |
| dna microarray-based global transcriptional profiling of yersinia pestis in multicellularity. | yersinia pestis, the causative agent of plague, has a feature of forming multicellular aggregates at liquid-air interface around the wall of glass tube. in this study, we employed the whole-genome dna microarray of y. pestis to investigate the global transcriptional profile in multicellularity compared with that in its plank-tonic growth. a total of 177 genes were differentially expressed in y. pestis during early stage of multicellular formation; seventy genes of them were up-regulated while 10 ... | 2008 | 18974958 |
| are carnivores universally good sentinels of plague? | sylvatic plague, caused by the bacterium yersinia pestis, is a flea-borne disease that primarily affects rodents but has been detected in over 200 mammal species worldwide. mammalian carnivores are routinely surveyed as sentinels of local plague activity, since they can present antibodies to y. pestis infection but show few clinical signs. in boulder county, colorado, usa, plague epizootic events are episodic and occur in black-tailed prairie dogs. enzootic hosts are unidentified as are plague f ... | 2009 | 18973449 |
| repeatability and pattern recognition of bacterial fatty acid profiles generated by direct mass spectrometric analysis of in situ thermal hydrolysis/methylation of whole cells. | direct ci mass spectrometry profiling of fatty acid methyl esters (fames) from in situ thermal hydrolysis/methylation (thm) of whole bacterial cells with tetramethylammonium hydroxide (tmah) has been demonstrated as a potential method for real time and fieldable detection/identification of microorganisms. bacillus anthracis (ames), yersinia pestis (nair. kenya), vibrio cholerae (e1 tor), brucella melitensis (abortus wild) and francisella tularensis (lvs vaccine) were profiled by this method duri ... | 2003 | 18968943 |
| ocular plague (yersinia pestis) in mule deer (odocoileus hemionus) from wyoming and oregon. | although plague is relatively rare in wild ungulates, this report describes ocular lesions associated with yersinia pestis infection in three free-ranging mule deer (odocoileus hemionus) from wyoming and oregon, usa. all deer were observed antemortem and seemed to be blind. post-mortem examination revealed gross lesions of bilateral keratoconjunctivitis and/or panophthalmitis in the first two deer, but only partial retinal detachment in the third deer. microscopically, all deer had moderate-to-s ... | 2008 | 18957655 |
| immunization of black-tailed prairie dog against plague through consumption of vaccine-laden baits. | prairie dogs (cynomys spp.) are highly susceptible to yersinia pestis and, along with other wild rodents, are significant reservoirs of plague for other wildlife and humans in the western united states. a recombinant raccoon poxvirus, expressing the f1 antigen of y. pestis, was incorporated into a palatable bait and offered to three groups (n = 18, 19, and 20) of black-tailed prairie dogs (cynomys ludovicianus) for voluntary consumption, either one, two, or three times, at roughly 3-wk intervals ... | 2008 | 18957649 |
| the yersinia pseudotuberculosis and yersinia pestis toxin complex is active against cultured mammalian cells. | the toxin complex (tc) genes were first identified in the insect pathogen photorhabdus luminescens and encode approximately 1 mda protein complexes which are toxic to insect pests. subsequent genome sequencing projects have revealed the presence of tc orthologues in a range of bacterial pathogens known to be associated with insects. interestingly, members of the mammalian-pathogenic yersiniae have also been shown to encode tc orthologues. studies in yersinia enterocolitica have shown that diverg ... | 2008 | 18957603 |
| substrains of 129 mice are resistant to yersinia pestis kim5: implications for interleukin-10-deficient mice. | interleukin-10 (il-10)-deficient mice are resistant to several pathogens, including yersinia pestis. surprisingly, we observed that heterozygous il-10(+/-) mice also survive high-dose intravenous infection with y. pestis kim5 (pgm(-)). analysis of commercial il-10(-/-) mice revealed that at least 30 cm of genomic dna from the original 129 strain remains, including a functional slc11a1 (nramp1) gene. interestingly, two substrains of 129 mice were resistant to high-dose y. pestis kim5. resistance ... | 2009 | 18955473 |
| an il-12 dna vaccine co-expressing yersinia pestis antigens protects against pneumonic plague. | pneumonic plague remains problematic in endemic areas, and because it can be readily transmitted and has high mortality, the development of efficacious vaccines is warranted. to test whether stimulation of cell-mediated immunity with il-12 will improve protective immunity against plague, we constructed two il-12 dna vaccines using a bicistronic plasmid encoding the protective plague epitopes, capsular (f1) antigen and virulence antigen (v-ag) as f1-v fusion protein and v-ag only, respectively. w ... | 2009 | 18955097 |
| electrical microarrays for highly sensitive detection of multiplex pcr products from biological agents. | for the sensitive detection of amplicons derived from diagnostic pcr, a novel electrical low-density microarray is applied and compared to state-of-the-art quantitative real-time pcr. the principle of the electrochemical method and the effective use for analysis are described. interdigitated array gold electrodes (ida-e) embedded into a silicon chip are the core technology of the fully automated compact biosensor system, basing on enzyme coupled electrochemical detection. the biointerface is bui ... | 2009 | 18954971 |
| [should we still fear the plague today?]. | 2008 | 18950584 | |
| scavenging by mammalian carnivores on prairie dog colonies: implications for the spread of plague. | plague causes mass mortality of prairie dogs (cynomys ludovicianus) in shortgrass steppe. although the pathogen, the bacterium yersinia pestis, is spread within colonies by flea bites or contact between infected hosts, it is unclear how y. pestis is transported over long distances between isolated colonies. one possibility is that wideranging, plague-resistant mammalian carnivores pick up fleas when scavenging prairie dog carcasses. using guinea pigs as surrogates for prairie dogs, we compared h ... | 2009 | 18945188 |
| a novel autotransporter adhesin is required for efficient colonization during bubonic plague. | many proteins secreted by the type v secretion system (autotransporters) have been linked to virulence in gram-negative bacteria. several putative conventional autotransporters are present in the yersinia pestis genome, but only one, yape, is conserved in the other pathogenic yersinia species. here, we introduce yape and demonstrate that it is secreted via a type v mechanism. inactivation of yape in y. pestis results in decreased efficiency in colonization of tissues during bubonic infection. co ... | 2009 | 18936182 |
| loss of a biofilm-inhibiting glycosyl hydrolase during the emergence of yersinia pestis. | yersinia pestis, the bacterial agent of plague, forms a biofilm in the foregut of its flea vector to produce a transmissible infection. the closely related yersinia pseudotuberculosis, from which y. pestis recently evolved, can colonize the flea midgut but does not form a biofilm in the foregut. y. pestis biofilm in the flea and in vitro is dependent on an extracellular matrix synthesized by products of the hms genes; identical genes are present in y. pseudotuberculosis. the yersinia hms protein ... | 2008 | 18931111 |
| aryl acid adenylating enzymes involved in siderophore biosynthesis: fluorescence polarization assay, ligand specificity, and discovery of non-nucleoside inhibitors via high-throughput screening. | the design and synthesis of a fluorescent probe fl-sal-ams 6 based on the tight-binding inhibitor 5'- o-[ n-(salicyl)sulfamoyl]adenosine (sal-ams) is described for the aryl acid adenylating enzymes (aaaes) known as mbta, ybte, ente, vibe, dhbe, and base involved in siderophore biosynthesis from mycobacterium tuberculosis, yersinia pestis, escherichia coli, vibrio cholerae, bacillus subtilis, and acinetobacter baumannii, respectively. the probe was successfully used to develop a fluorescence pola ... | 2008 | 18928302 |
| antibodies and cytokines independently protect against pneumonic plague. | yersinia pestis causes pneumonic plague, an exceptionally virulent disease for which we lack a safe and effective vaccine. antibodies specific for the y. pestis f1 and lcrv proteins can protect mice against pulmonary y. pestis infection. we demonstrate that neutralizing tumor necrosis factor-alpha (tnfalpha) and gamma-interferon (ifngamma) abrogates this protection at sub-optimal levels of f1- or lcrv-specific antibody, but not at optimal levels. moreover, we demonstrate that endogenous tnfalpha ... | 2008 | 18926869 |
| artificial plasmid engineered to simulate multiple biological threat agents. | the objective of this study was to develop a non-virulent simulant to replace several virulent organisms during the development of detection and identification methods for biological threat agents. we identified and selected specific genes to detect yersinia pestis, francisella tularensis, burkholderia mallei, burkholderia pseudomallei, rickettsia sp., coxiella burnetii, brucella sp., enterohemorrhagic escherichia coli o157:h7, bacillus anthracis, and variola (smallpox) virus. we then designed a ... | 2009 | 18923830 |
| positive selection, not negative selection, in the pseudogenization of rcsa in yersinia pestis. | 2008 | 18922766 | |
| toll-like receptor 6 drives differentiation of tolerogenic dendritic cells and contributes to lcrv-mediated plague pathogenesis. | educating dendritic cells (dc) to become tolerogenic dc, which promote regulatory il-10 immune responses, represents an effective immune evasion strategy for pathogens. yersinia pestis virulence factor lcrv is reported to induce il-10 production via interaction with toll-like receptor (tlr) 2. however, tlr2-/- mice are not protected against subcutaneous plague infection. using complementary in vitro and in vivo approaches and lcrv as a model, we show that tlr6 associates with tlr2 to induce tole ... | 2008 | 18854239 |
| [study on the epidemiological significance related to community-structural difference of the rat plague host and vectors in western yunnan, china]. | to study the epidemiological significance of community-structural difference regarding both small mammal and flea communities on rattus flavipectus in dehong and baoshan areas, yunnan province, during 1982 to 1996. | 2008 | 18843991 |
| immune defense against pneumonic plague. | summary: yersinia pestis is one of the world's most virulent human pathogens. inhalation of this gram-negative bacterium causes pneumonic plague, a rapidly progressing and usually fatal disease. extensively antibiotic-resistant strains of y. pestis exist and have significant potential for exploitation as agents of terrorism and biowarfare. subunit vaccines comprised of the y. pestis f1 and lcrv proteins are well-tolerated and immunogenic in humans but cannot be tested for efficacy, because pneum ... | 2008 | 18837787 |
| yersinia pestis evades tlr4-dependent induction of il-12(p40)2 by dendritic cells and subsequent cell migration. | at the temperature of its flea vector (approximately 20-30 degrees c), the causative agent of plague, yersinia pestis, expresses a profile of genes distinct from those expressed in a mammalian host (37 degrees c). when dendritic cells (dc) are exposed to y. pestis grown at 26 degrees c (y. pestis-26 degrees), they secrete copious amounts of il-12p40 homodimer (il-12(p40)(2)). in contrast, when dcs are exposed to y. pestis grown at 37 degrees c (y. pestis-37 degrees), they transcribe very little ... | 2008 | 18832714 |
| single-dose, virus-vectored vaccine protection against yersinia pestis challenge: cd4+ cells are required at the time of challenge for optimal protection. | we have developed an experimental recombinant vesicular stomatitis virus (vsv) vectored plague vaccine expressing a secreted form of yersinia pestis low calcium response protein v (lcrv) from the first position of the vsv genome. this vector, given intramuscularly in a single dose, induced high-level antibody titers to lcrv and gave 90-100% protection against pneumonic plague challenge in mice. this single-dose protection was significantly better than that generated by vsv expressing the non-sec ... | 2008 | 18832004 |
| engineered saccharomyces cerevisiae strain for improved xylose utilization with a three-plasmid sumo yeast expression system. | a three-plasmid yeast expression system utilizing the portable small ubiquitin-like modifier (sumo) vector set combined with the efficient endogenous yeast protease ulp1 was developed for production of large amounts of soluble functional protein in saccharomyces cerevisiae. each vector has a different selectable marker (ura, trp, or leu), and the system provides high expression levels of three different proteins simultaneously. this system was integrated into the protocols on a fully automated p ... | 2009 | 18831987 |
| source of host blood affects prevalence of infection and bacterial loads of yersinia pestis in fleas. | yersinia pestis, the etiological agent of plague, is transmitted by multiple flea species. previous studies have reported wide variability in transmission efficiency among competent vectors. however, it is unclear to what extent such variation is explained by methodological differences among studies. to optimize an artificial feeding system where fleas are infected with controlled numbers of y. pestis under standardized laboratory conditions that could be used to systematically compare vector ef ... | 2008 | 18826038 |
| [role of fleas, the principal and secondary plague vectors, in the circulation of the causative agent in siberian natural foci]. | the paper reviews data on the role of fleas as the principal and secondary vectors of infection in the siberian natural foci of plague. the role of citellophilus tesquorum as the principal plague vectors in the transbaikalian and tuvinian natural foci is shown to be determined by their ecological characteristics (the degree of specificity to the main host, numbers, and natural infection) to a greater extent and by the rate of block formation to a lesser extent. the significance of principal and ... | 2008 | 18822506 |
| [role of yersinia pestis biofilms in mechanisms of plague enzootics]. | 2008 | 18819421 | |
| [interaction of s- and r-lipopolysaccharides of francisella tularensis with lypopolysaccharide-binding protein of human serum]. | investigation of ability of francisella tularensis s- and r-lypopolysaccharide (lps) preparations as well as the live bacteria with different chemotypes to interact with human lypopolysaccharide-binding protein (lbp) was carried out. it was found that lps preparations derived from virulent(s-lps) or isogenic avirulent mutant (r-lps) strains of f. tularensis had markedly lower affinity to lbp as compared with typical s-lps of salmonella abortus and r-lps of yersinia pestis. it was shown that r-lp ... | 2008 | 18819401 |
| adaptive strategies of yersinia pestis to persist during inter-epizootic and epizootic periods. | plague is a flea-borne zoonotic bacterial disease caused by yersinia pestis. it has caused three historical pandemics, including the black death which killed nearly a third of europe's population in the 14th century. in modern times, plague epizootics can extirpate entire susceptible wildlife populations and then disappear for long time periods. understanding how y. pestis is maintained during inter-epizootic periods and the factors responsible for transitioning to epizootics is important for pr ... | 2009 | 18803931 |
| immunization with recombinant v10 protects cynomolgus macaques from lethal pneumonic plague. | vaccine and therapeutic strategies that prevent infections with yersinia pestis have been sought for over a century. immunization with live attenuated (nonpigmented) strains and immunization with subunit vaccines containing recombinant low-calcium-response v antigen (rlcrv) and recombinant f1 (rf1) antigens are considered effective in animal models. current antiplague subunit vaccines in development for utilization in humans contain both antigens, either as equal concentrations of the two compon ... | 2008 | 18794281 |
| genome-wide analysis of single nucleotide polymorphisms in bordetella pertussis using comparative genomic sequencing. | bordetella pertussis is known to be a genotypically homogeneous pathogen but the extent of homogeneity at the genomic level is unknown. a currently circulating b. pertussis isolate from australia was compared with the genome-sequenced tohama i strain isolated in japan in the 1950s from a distantly related lineage. microarray-based comparative genome sequencing (cgs) was used to detect single nucleotide polymorphisms (snps) in a total of 1.4 mb of the 4.09 mb genome, including 1012 coding-regions ... | 2008 | 18790049 |
| transmission efficiency of two flea species (oropsylla tuberculata cynomuris and oropsylla hirsuta) involved in plague epizootics among prairie dogs. | plague, caused by yersinia pestis, is an exotic disease in north america circulating predominantly in wild populations of rodents and their fleas. black-tailed prairie dogs (cynomys ludovicianus) are highly susceptible to infection, often experiencing mortality of nearly all individuals in a town as a result of plague. the fleas of black-tailed prairie dogs are oropsylla tuberculata cynomuris and oropsylla hirsuta. we tested the efficiency of o. tuberculata cynomuris to transmit y. pestis daily ... | 2008 | 18787922 |
| ecohealth and the black death in the year of the rat. | 2008 | 18787913 | |
| evolution, population structure, and phylogeography of genetically monomorphic bacterial pathogens. | genetically monomorphic bacteria contain so little sequence diversity that sequencing a few gene fragments yields little or no information. as a result, our understanding of their evolutionary patterns presents greater technical challenges than exist for genetically diverse microbes. these challenges are now being met by analyses at the genomic level for diverse types of genetic variation, the most promising of which are single nucleotide polymorphisms. many of the most virulent bacterial pathog ... | 2008 | 18785837 |
| preliminary validation of real-time pcr assays for the identification of yersinia pestis. | yersinia pestis (y. pestis) is a zoonotic bacterium mainly circulating among rodents and their fleas. transmission to humans can cause bubonic, pneumonic or septicemic plague with a high case-fatality rate. therefore, rapid and reliable diagnostic tools are crucial. the objective of this study was to assess the inter-laboratory reproducibility of in-house developed real-time pcr assays for the identification of y. pestis. | 2008 | 18783342 |
| [macro- and microevolution as related to the problem of origin and global expansion of the plague pathogen yersinia pestis]. | the ratio of macro- and microevolutionary processes is considered with reference to the ecological scenario of the origin of the plague pathogen and its subsequent natural and anthropogenic global expansion. the macroevolutionary transformation of the ancestral pseudotuberculosis microbe clone into the initial plague microbe yersinia pestis tarbagani occurred in central asia at the end of the late pleistocene by a "vertical" darwinian way in an inadaptive heterothermal continual intermediate env ... | 2008 | 18773526 |
| vaccination of mice with a yop translocon complex elicits antibodies that are protective against infection with f1- yersinia pestis. | yersinia pestis, the bacterial agent of plague, secretes several proteins important for pathogenesis or host protection. the f1 protein forms a capsule on the bacterial cell surface and is a well-characterized protective antigen but is not essential for virulence. a type iii secretion system that is essential for virulence exports yop proteins, which function as antiphagocytic or anti-inflammatory factors. yop effectors (e.g., yope) are delivered across the host cell plasma membrane by a translo ... | 2008 | 18765742 |
| human plague in the usa: the importance of regional and local climate. | a 56-year time series of human plague cases (yersinia pestis) in the western united states was used to explore the effects of climatic patterns on plague levels. we found that the pacific decadal oscillation (pdo), together with previous plague levels and above-normal temperatures, explained much of the plague variability. we propose that the pdo's impact on plague is conveyed via its effect on precipitation and temperature and the effect of precipitation and temperature on plague hosts and vect ... | 2008 | 18765356 |
| environmental monitoring for biological threat agents using the autonomous pathogen detection system with multiplexed polymerase chain reaction. | we have developed and field-tested a now operational civilian biodefense capability that continuously monitors the air in high-risk locations for biological threat agents. this stand-alone instrument, called the autonomous pathogen detection system (apds), collects and selectively concentrates particles from the air into liquid samples and analyzes the samples using multiplexed pcr amplification coupled with microsphere array detection. during laboratory testing, we evaluated the apds instrument ... | 2008 | 18763806 |
| transcriptional profiling of a mice plague model: insights into interaction between yersinia pestis and its host. | despite the importance of pneumonic plague caused by yersinia pestis, a few is known about the interaction between y. pestis and its host at the molecular level during the pneumonic plague development. in this study, we employed an intranasally challenged plague model in mice for investigating the kinetics of the disease progression by transcriptional profiling of y. pestis and mice using qrt-pcr and microarray, respectively. the increasing transcription of important virulence genes of y. pestis ... | 2009 | 18759226 |
| long-term persistence of virulent yersinia pestis in soil. | plague is characterized by geographical foci from which it re-emerges after decades of silence, a fact currently explained by enzootic and epizootic cycles between plague-susceptible and plague-resistant rodents. to assess the potential role of soil in plague epidemiology, we experimentally investigated whether yersinia pestis could persist alive and virulent in soil. sterilized soil inoculated with virulent y. pestis biotype orientalis was regularly sampled for 40 weeks in duplicate. each sampl ... | 2008 | 18757820 |
| [development of a multiplex pcr for detection of the yersinia genus with identification of pathogenic species (y. pestis, y. pseudotuberculosis, y. enterocolitica)]. | to identify the yersinia genus and pathogenic species (y. pestis, y. pseudotuberculosis, y. enterocolitica) in a single reaction a multiplex pcr technique was developed. it was optimized by five compounds of pcr buffer and temperature of primers annealing. the multiplex pcr provides an improved and rapid method for detection of the yersinia genus and identification of pathogenic species. | 2008 | 18756819 |
| determination of pyrophosphorylated forms of lipid a in gram-negative bacteria using a multivaried mass spectrometric approach. | lipid a isolated from several bacteria (escherichia coli, pseudomonas aeruginosa, salmonella enterica, and various strains of yersinia) showed abundant formation of pyrophosphate anions upon ion dissociation. pyrophosphate [h(3)p(2)o(7)](-) and/or [hp(2)o(6)](-) anions were observed as dominant fragments from diphosphorylated lipid a anions regardless of the ionization mode (matrix-assisted laser desorption ionization or electrospray ionization), excitation mode (collisional activation or infrar ... | 2008 | 18753624 |
| a comparative biochemical and structural analysis of the intracellular chorismate mutase (rv0948c) from mycobacterium tuberculosis h(37)r(v) and the secreted chorismate mutase (y2828) from yersinia pestis. | the rv0948c gene from mycobacterium tuberculosis h(37)r(v) encodes a 90 amino acid protein as the natural gene product with chorismate mutase (cm) activity. the protein, 90-mtcm, exhibits michaelis-menten kinetics with a k(cat) of 5.5+/-0.2s(-1) and a k(m) of 1500+/-100microm at 37 degrees c and ph7.5. the 2.0a x-ray structure shows that 90-mtcm is an all alpha-helical homodimer (protein data bank id: 2qbv) with the topology of escherichia coli cm (eccm), and that both protomers contribute to ea ... | 2008 | 18727669 |
| lipid a mimetics are potent adjuvants for an intranasal pneumonic plague vaccine. | an effective intranasal (i.n.) vaccine against pneumonic plague was developed. the formulation employed two synthetic lipid a mimetics as adjuvant combined with yersinia pestis-derived v- and f1-protective antigens. the two nontoxic lipid a mimetics, classed as amino-alkyl glucosaminide 4-phosphates (agps) are potent ligands for the toll-like receptor (tlr) 4. using a murine (balb/c) pneumonic plague model, we showed a single i.n. application of the vaccine provided 63% protection within 21 days ... | 2008 | 18722493 |
| vibrio cholerae o139 multiple-drug resistance mediated by yersinia pestis pip1202-like conjugative plasmids. | a conjugative plasmid, pmrv150, which mediated multiple-drug resistance (mdr) to at least six antibiotics, including ampicillin, streptomycin, gentamicin, tetracycline, chloramphenicol, and trimethoprim-sulfamethoxazole, was identified in a vibrio cholerae o139 isolate from hangzhou, eastern china, in 2004. according to partial pmrv150 dna sequences covering 15 backbone regions, the plasmid is most similar to pip1202, an inca/c plasmid in an mdr yersinia pestis isolate from a madagascar bubonic ... | 2008 | 18710912 |
| the cyclic amp receptor protein, crp, is required for both virulence and expression of the minimal crp regulon in yersinia pestis biovar microtus. | the cyclic amp receptor protein (crp) is a bacterial regulator that controls more than 100 promoters, including those involved in catabolite repression. in the present study, a null deletion of the crp gene was constructed for yersinia pestis bv. microtus strain 201. microarray expression analysis disclosed that at least 6% of y. pestis genes were affected by this mutation. further reverse transcription-pcr and electrophoretic mobility shift assay analyses disclosed a set of 37 genes or putative ... | 2008 | 18710863 |