Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| humans and evolutionary and ecological forces shaped the phylogeography of recently emerged diseases. | the development of human civilizations and global commerce has led to the emergence and worldwide circulation of many infectious diseases. anthrax, plague and tularaemia are three zoonotic diseases that have been intensely studied through genome characterization of the causative species and phylogeographical analyses. a few highly fit genotypes in each species represent the causative agents for most of the observed disease cases. together, mutational and selective forces create highly adapted pa ... | 2009 | 19820723 |
| draft genome sequences of yersinia pestis isolates from natural foci of endemic plague in china. | to gain insights into the evolutionary origin, emergence, and pathogenicity of the etiologic agent of plague, we have sequenced the genomes of four yersinia pestis strains isolated from the zoonotic rodent reservoir in foci of endemic plague in china. these resources enable in-depth studies of y. pestis sequence variations and detailed whole-genome comparisons of very closely related genomes from the supposed site of the origin and the emergence of global pandemics of plague. | 2009 | 19820101 |
| spatial variation of yersinia pestis from yunnan province of china. | yunnan province of china is considered the site of origin for modern plague. we analyzed the genotypes of eight yersinia pestis strains isolated from three counties in yunnan province by pulse field gel electrophoresis (pfge). pfge showed that strains isolated from the same site were identical regardless of hosts or year of isolation. however, y. pestis strains isolated from geographically distinct loci were genetically divergent. whole genome sequences of two strains from two foci in yunnan sho ... | 2009 | 19815893 |
| [phenomenon of yersinia pestis biofilm formation in flea organism]. | for the first time substantiated was the role of the phenomenon of yersinia pestis biofilm--extracellular matrix envelope (eme)--formation as the basis that determines the nature of plague agent interaction with flea organism. implication of vector's proventriculus in the process of biofilm formation was demonstrated. ultrastucture of plague microbe conglomerates in flea proventriculus and midgut was analysed and uniform mechanism of their formation was elucidated. the role of yersinia pestis bi ... | 2009 | 19807044 |
| volatile antimicrobials from muscodor crispans, a novel endophytic fungus. | muscodor crispans is a recently described novel endophytic fungus of ananas ananassoides (wild pineapple) growing in the bolivian amazon basin. the fungus produces a mixture of volatile organic compounds (vocs); some of the major components of this mixture, as determined by gc/ms, are propanoic acid, 2-methyl-, methyl ester; propanoic acid, 2-methyl-; 1-butanol, 3-methyl-;1-butanol, 3-methyl-, acetate; propanoic acid, 2-methyl-, 2-methylbutyl ester; and ethanol. the fungus does not, however, pro ... | 2010 | 19797357 |
| clinical and pathologic features of cynomolgus macaques (macaca fascicularis) infected with aerosolized yersinia pestis. | since the anthrax attacks of 2001, the emphasis on developing animal models of aerosolized select agent pathogens has increased. many scientists believe that nonhuman primate models are the most appropriate to evaluate pulmonary response to, vaccines for, and treatments for select agents such as yersinia pestis (y. pestis), the causative agent of plague. a recent symposium concluded that the cynomolgus macaque (macaca fascicularis) plague model should be characterized more fully. to date, a well ... | 2008 | 19793459 |
| higher accumulation of f1-v fusion recombinant protein in plants after induction of protein body formation. | improving foreign protein accumulation is crucial for enhancing the commercial success of plant-based production systems since product yields have a major influence on process economics. cereal grain evolved to store large amounts of proteins in tightly organized aggregates. in maize, gamma-zein is the major storage protein synthesized by the rough endoplasmic reticulum (er) and stored in specialized organelles called protein bodies (pb). zera (gamma-zein er-accumulating domain) is the n-termina ... | 2010 | 19789982 |
| plague vaccines and the molecular basis of immunity against yersinia pestis. | yersinia pestis is the causative agent of bubonic and pneumonic plague, human diseases with high mortality. due to the microbe's ability to spread rapidly, plague epidemics present a serious public health threat. a search for prophylactic measures was initially based on historical reports of bubonic plague survivors and their apparent immunity. due to safety and efficacy concerns, killed whole-cell preparations or live-attenuated plague vaccines are no longer considered in the united states. vac ... | 2009 | 19786842 |
| n255 is a key residue for recognition by a monoclonal antibody which protects against yersinia pestis infection. | mab7.3 to yersinia pestis lcrv antigen (lcrv(ype)) protected j774a.1 macrophages in vitro from killing by a yersinia pseudotuberculosis strain expressing lcrv(ype). of 4 site-directed mutations in the coiled-coil region (148-169) and 7 mutations in the 225-255 sequence of lcrv(ype), only the mutation of n255 to d255, abrogated the binding of mab7.3 and reduced its protective capacity against plague. since the mab7.3 epitope in lcrv(ype) (135-275) encompasses a region (136-180) thought to be expo ... | 2009 | 19786138 |
| humoral immune responses and protective efficacy of sequential b- and t-cell epitopes of v antigen of yersinia pestis by intranasal immunization in microparticles. | capsular f1 and secretory v antigen are the putative vaccine candidates for plague, caused by yersinia pestis. contemplating this, we studied the immunogenicity and protective efficacy of collinearly synthesized b- and t-cell epitopes (b-t constructs) of v antigen entrapped in poly (dl-lactide-co-glycolide) microparticles immunized intranasally using single dose immunization schedule in outbred, h-2(b) and h-2(d) mice. high antibody levels were observed in terms of igg, iga and siga peak titers ... | 2009 | 19779739 |
| mlva distribution characteristics of yersinia pestis in china and the correlation analysis. | yersinia pestis, the aetiological agent of plague, has been well defined genotypically on local and worldwide scales. in november 2005, five cases of severe pneumonia of unknown causes, resulting in two deaths, were reported in yulong, yunnan province. in this study, we compared y. pestis isolated from the yulong focus to strains from other areas. | 2009 | 19775435 |
| the nlpd lipoprotein is a novel yersinia pestis virulence factor essential for the development of plague. | yersinia pestis is the causative agent of plague. previously we have isolated an attenuated y. pestis transposon insertion mutant in which the pcm gene was disrupted. in the present study, we investigated the expression and the role of pcm locus genes in y. pestis pathogenesis using a set of isogenic sure, pcm, nlpd and rpos mutants of the fully virulent kimberley53 strain. we show that in y. pestis, nlpd expression is controlled from elements residing within the upstream genes sure and pcm. the ... | 2009 | 19759820 |
| reduced apoptosis of mouse macrophages induced by yscw mutant of yersinia pestis results from the reduced secretion of yopj and relates to caspase-3 signal pathway. | the virulence of the pathogenic yersinia species depends on a plasmid-encoded type iii secretion system (t3ss) that injects six yersinia outer protein (yop) effector proteins into the cytosol of macrophages, leading to disruption of host defence mechanisms. here, we report that a t3ss structural protein yscw of yersinia pestis contributed to the induction of apoptosis of murine macrophages. the apoptotic percentage of macrophages, from both mouse peritoneal cavity and spleen, and of raw264.7 cel ... | 2009 | 19751270 |
| structures of the arm-type binding domains of hpi and hai7 integrases. | the structures of the n-terminal domains of two integrases of closely related but not identical asn tdna-associated genomic islands, yersinia hpi (high pathogenicity island; encoding siderophore yersiniabactin biosynthesis and transport) and an erwinia carotovora genomic island with yet unknown function, hai7, have been resolved. both integrases utilize a novel four-stranded beta-sheet dna-binding motif, in contrast to the known proteins that bind their dna targets by means of three-stranded bet ... | 2009 | 19737930 |
| deletion of braun lipoprotein gene (lpp) attenuates yersinia pestis kim/d27 strain: role of lpp in modulating host immune response, nf-kappab activation and cell death. | the pathogenic species of yersiniae potently blocks immune responses in host cells by using the type iii secretion apparatus and its effector proteins. in this study, we characterized potential mechanisms associated with the braun lipoprotein (lpp) that contributed to a further attenuation of a pigmentation locus-minus yersinia pestis kim/d27 mutant strain and its ability to generate immune responses in mice. the lpp gene encodes one of the major outer membrane lipoproteins that is involved in i ... | 2010 | 19737605 |
| innate immune response during yersinia infection: critical modulation of cell death mechanisms through phagocyte activation. | yersinia pestis, the etiological agent of plague, is one of the most deadly pathogens on our planet. this organism shares important attributes with its ancestral progenitor, yersinia pseudotuberculosis, including a 70-kb virulence plasmid, lymphotropism during growth in the mammalian host, and killing of host macrophages. infections with both organisms are biphasic, where bacterial replication occurs initially with little inflammation, followed by phagocyte influx, inflammatory cytokine producti ... | 2009 | 19734471 |
| polyphosphate and omptins: novel bacterial procoagulant agents. | derangement of the blood clotting system contributes strongly to multiple organ failure in severe sepsis. in this review, we examine two microbial modulators of the clotting system: polyphosphates and omptins. polyphosphates are linear polymers of inorganic phosphate that are abundant in the acidocalcisomes of prokaryotes and unicellular organisms as well as in the dense granules of human platelets. polyphosphates modulate haemostasis by: (1) triggering clotting via the contact pathway; (2) acce ... | 2009 | 19725923 |
| caspase-12 and the inflammatory response to yersinia pestis. | caspase-12 functions as an antiinflammatory enzyme inhibiting caspase-1 and the nod2/rip2 pathways. due to increased susceptibility to sepsis in individuals with functional caspase-12, an early-stop mutation leading to the loss of caspase-12 has replaced the ancient genotype in eurasia and a significant proportion of individuals from african populations. in african-americans, it has been shown that caspase-12 inhibits the pro-inflammatory cytokine production. | 2009 | 19721713 |
| [the autoagglutination factor of plague pathogen--cross-reacting antigen]. | an antigen similar to the autoagglutination factor (af) of plague pathogen in immunochemical specificity was sought in 22 bacterial species. for this, an immunoglobulin anti-af diagnosticum that is the sheep erythrocytes sensitized with rabbit immune serum to the af preparation isolated from the plasmid-free variant of the yersinia pestis strain ev76. the bacteriological study applying a passive hemagglutination assay revealed af-like antigens not only in all study strains (n = 30) of y. pestis, ... | 2009 | 19718822 |
| evaluation of a yersinia pestis mutant impaired in a thermoregulated type vi-like secretion system in flea, macrophage and murine models. | type vi secretion systems (t6sss) have been identified recently in several gram-negative organisms and have been shown to be associated with virulence in some bacterial pathogens. a t6ss of yersinia pestis co92 (locus ypo0499-ypo0516) was deleted followed by investigation of the phenotype of this mutation. we observed that this t6ss locus of y. pestis was preferentially expressed at 26 degrees c in comparison to 37 degrees c suggesting a possible role in the flea cycle. however, we found that th ... | 2009 | 19716410 |
| typing methods for the plague pathogen, yersinia pestis. | phenotypic and genotypic methodologies have been used to differentiate the etiological agent of plague, yersinia pestis. historically, phenotypic methods were used to place isolates into one of three biovars based on nitrate reduction and glycerol fermentation. classification of y. pestis into genetic subtypes is problematic due to the relative monomorphic nature of the pathogen. resolution into groups is dependent on the number and types of loci used in the analysis. the last 5-10 years of rese ... | 2009 | 19714987 |
| yersinia pestis can bypass protective antibodies to lcrv and activation with gamma interferon to survive and induce apoptosis in murine macrophages. | yersinia pestis, the agent of plague, uses a type iii secretion injectisome to deliver yop proteins into macrophages to counteract phagocytosis and induce apoptosis. additionally, internalized y. pestis can survive in the phagosomes of naïve or gamma interferon (ifn-gamma)-activated macrophages by blocking vacuole acidification. the y. pestis lcrv protein is a target of protective antibodies. the binding of antibodies to lcrv at the injectisome tip results in neutralization of the apoptosis of y ... | 2009 | 19710295 |
| n-hydroxybenzimidazole inhibitors of the transcription factor lcrf in yersinia: novel antivirulence agents. | lcrf, a multiple adaptational response (mar) transcription factor, regulates virulence in yersinia pestis and yersinia pseudotuberculosis. in a search for small molecule inhibitors of lcrf, an acrylic amide series of n-hydroxybenzimidazoles was synthesized and the sar (structure-activity relationship) was examined. selected test compounds demonstrated inhibitory activity in a primary cell-free lcrf-dna binding assay as well as in a secondary whole cell assay (type iii secretion system dependent ... | 2009 | 19708663 |
| [structural and functional analysis of aran gene in the yersinia pestis strains of various origin]. | structural and functional analysis of the aran gene involved in regulation of expression of diagnostically significant symptom (arabinose fermentation) was performed in the yersinia pestis microorganism. lack of arabinose fermentation in the altai substrain, hissar substrain, and talas strains was shown to be due to solitary nucleotide insert into the aran gene. the insert is in the position 763 bp. the strains of the main, caucasian, and ulege substrains do not contain this mutation of the aran ... | 2009 | 19705779 |
| [results of the vntr-analysis in a locus (5'-naaa-3')n of strains yersinia pestis from the active natural foci of plague of siberia]. | the method of the vntr-analysis in a locus (5'-naaa-3')n was studied using samples of the dna of 73 strains y. pestis ssp. altaica, isolated in gorno-altaisk and 65 strains y. pestis ssp. pestis, allocated in tuva natural foci of plague. it was demonstrated that strains from the gorno-altaisk population of plague microbes possessed genomic polymorphism in the locus given a marker that is reflected in variability of the size of an amplicon from 250 up to 275 bp, correlating with places of isolati ... | 2009 | 19705777 |
| direct and negative regulation of the syco-ypka-ypoj operon by cyclic amp receptor protein (crp) in yersinia pestis. | pathogenic yersiniae, including y. pestis, share a type iii secretion system (t3ss) that is composed of a secretion machinery, a set of translocation proteins, a control system, and six yop effector proteins including ypka and yopj. the cyclic amp receptor protein (crp), a global regulator, was recently found to regulate the laterally acquired genes (pla and pst) in y. pestis. the regulation of t3ss components by crp is unknown. | 2009 | 19703315 |
| the role of rela and spot in yersinia pestis kim5 pathogenicity. | the ppgpp molecule is part of a highly conserved regulatory system for mediating the growth response to various environmental conditions. this mechanism may represent a common strategy whereby pathogens such as yersinia pestis, the causative agent of plague, regulate the virulence gene programs required for invasion, survival and persistence within host cells to match the capacity for growth. the products of the rela and spot genes carry out ppgpp synthesis. to investigate the role of ppgpp on g ... | 2009 | 19701461 |
| a rapid allele variant discrimination method for yersinia pestis strains based on high-resolution melting curve analysis. | yersinia pestis isolates were genotyped analyzing the polymorphic dna regions named variable number tandem repeats (vntr). allele variants were studied by high-resolution melting analysis (hrma) of polymerase chain reaction fragments obtained for 25 vntr loci. after comparison with previous results, 14 loci gave distinguishable normalized melting curves and allowed to correctly assign alleles. this hrma typing technique permits to differentiate y. pestis isolates and turned out to be robust, rep ... | 2009 | 19679229 |
| high-throughput identification of new protective antigens from a yersinia pestis live vaccine by enzyme-linked immunospot assay. | yersinia pestis, the plague pathogen, is a facultative intracellular bacterium. cellular immunity plays important roles in defense against infections. the identification of t-cell targets is critical for the development of effective vaccines against intracellular bacteria; however, the function of cellular immunity in protection from plague was not clearly understood. in this study, 261 genes from y. pestis were selected on the basis of bioinformatics analysis and previous research results for e ... | 2009 | 19651863 |
| studies of vector competency and efficiency of north american fleas for yersinia pestis: state of the field and future research needs. | the etiological agent of plague, yersinia pestis, is most commonly transmitted by the bite of infectious fleas. to date, at least 28 flea species occurring in north america have been experimentally confirmed as vectors of y. pestis. transmission efficiency differs among species and also between different studies of a single species. these differences may, however, in large part reflect nonstandardized experimental conditions used during the first half of the 20th century when such studies were c ... | 2009 | 19645275 |
| novel broad-spectrum bis-(imidazolinylindole) derivatives with potent antibacterial activities against antibiotic-resistant strains. | given the limited number of structural classes of clinically available antimicrobial drugs, the discovery of antibacterials with novel chemical scaffolds is an important strategy in the development of effective therapeutics for both naturally occurring and engineered resistant strains of pathogenic bacteria. in this study, several diarylamidine derivatives were evaluated for their ability to protect macrophages from cell death following infection with bacillus anthracis, a gram-positive spore-fo ... | 2009 | 19635954 |
| protection against anthrax and plague by a combined vaccine in mice and rabbits. | the protective antigen (pa) of bacillus anthracis and the fraction 1 capsular antigen (f1 antigen), v antigen of yersinia pestis have been demonstrated to be potential immunogens and candidate vaccine sub-units against anthrax and plague respectively. in this study, the authors have investigated the antibody responses and the protective efficacy when the antigens were administered separately or in combination intramuscularly formulation adsorbed to an aluminum hydroxide adjuvant. results show th ... | 2009 | 19635609 |
| bubonic and pneumonic plague - uganda, 2006. | plague is a life-threatening fleaborne disease caused by the bacterium yersinia pestis. the most common clinical form is bubonic plague, which is characterized by high fever and regional lymphadenitis. without treatment, infection can spread from lymph nodes to the lungs, resulting in pneumonic plague and the potential for person-to-person transmission through respiratory droplets. in november 2006, the uganda ministry of health received reports of an increase in bubonic plague cases and a possi ... | 2009 | 19629028 |
| [comparative genetic characteristic of vaccine strain of yersinia pestis ev and its putative "virulent derivatives"]. | to perform a comparison of genetic characteristics of vaccine strain ev and its putative "virulent derivatives", obtained after passages through highly susceptible animals, in order to identify the strains-"revertants" and establish their possible origin. | 2009 | 19621820 |
| [infectious-toxic model of plague in mice]. | to develop infectious-toxic model of plague in mice and to assess perspectives of its use for selection of new vaccine preparations. | 2009 | 19621819 |
| d27-plpxl, an avirulent strain of yersinia pestis, primes t cells that protect against pneumonic plague. | vaccinating with live, conditionally attenuated, pigmentation (pgm)-deficient yersinia pestis primes t cells that protect mice against pneumonic plague. however, pgm-deficient strains are not considered safe for human use because they retain substantial virulence in animal models. y. pestis strains engineered to express escherichia coli lpxl are avirulent owing to constitutive production of lipopolysaccharide with increased toll-like receptor 4-activating ability. we generated an lpxl-expressing ... | 2009 | 19620344 |
| characterization of homologs of the small rna sgrs reveals diversity in function. | sgrs is a small rna (srna) that requires the rna chaperone hfq for its function. sgrs is a unique dual-function srna with a base pairing function that regulates mrna targets and an mrna function that allows production of the 43-amino-acid protein sgrt. sgrs is expressed when non-metabolizable sugars accumulate intracellularly (glucose-phosphate stress) and is required to allow escherichia coli cells to recover from stress. in this study, homologs of sgrs were used to complement an e. coli sgrs m ... | 2009 | 19620214 |
| in vitro intracellular trafficking of virulence antigen during infection by yersinia pestis. | yersinia pestis, the causative agent of plague, encodes several essential virulence factors on a 70 kb plasmid, including the yersinia outer proteins (yops) and a multifunctional virulence antigen (v). v is uniquely able to inhibit the host immune response; aid in the expression, secretion, and injection of the cytotoxic yops via a type iii secretion system (t3ss)-dependent mechanism; be secreted extracellularly; and enter the host cell by a t3ss-independent mechanism, where its activity is unkn ... | 2009 | 19609450 |
| plague into the 21st century. | 2009 | 19606935 | |
| oral vaccination with lcrv from yersinia pestis kim delivered by live attenuated salmonella enterica serovar typhimurium elicits a protective immune response against challenge with yersinia pseudotuberculosis and yersinia enterocolitica. | the use of live recombinant attenuated salmonella vaccines (rasv) synthesizing yersinia proteins is a promising approach for controlling infection by yersinia species. in this study, we constructed attenuated salmonella strains which synthesize a truncated form of lcrv, lcrv196 and evaluated the immune response and protective efficacy elicited by these strains in mice against two other major species of yersinia: yersinia pseudotuberculosis and yersinia enterocolitica. surprisingly, we found that ... | 2009 | 19596407 |
| involvement of the post-transcriptional regulator hfq in yersinia pestis virulence. | yersinia pestis is the causative agent of plague, which is transmitted primarily between fleas and mammals and is spread to humans through the bite of an infected flea or contact with afflicted animals. hfq is proposed to be a global post-transcriptional regulator that acts by mediating interactions between many regulatory small rnas (srnas) and their mrna targets. sequence comparisons revealed that y. pestis appears to produce a functional homologue of e. coli hfq. | 2009 | 19593436 |
| an evaluation of suspicious powder screening tools for first responders. | field screening tools are required which would allow first responders to quickly ascertain if a suspicious powder poses a potential threat necessitating additional testing for biological pathogens such as bacillus anthracis. in this study, three commercially available generic screening technologies were evaluated for the effectiveness to accurately differentiate between a hoax powder and a true biological threat. the biocheck kit was able to detect the following biological agents 1 x 10(8)cfu of ... | 2009 | 19592160 |
| deletion of braun lipoprotein gene (lpp) and curing of plasmid ppcp1 dramatically alter the virulence of yersinia pestis co92 in a mouse model of pneumonic plague. | deletion of the murein (braun) lipoprotein gene, lpp, attenuates the yersinia pestis co92 strain in mouse models of bubonic and pneumonic plague. in this report, we characterized the virulence of strains from which the plasminogen activating protease (pla)-encoding ppcp1 plasmid was cured from either the wild-type (wt) or the deltalpp mutant strain of y. pestis co92 in the mouse model of pneumonic infection. we noted a significantly increased survival rate in mice infected with the y. pestis ppc ... | 2009 | 19589835 |
| comparative antimicrobial activity of granulysin against bacterial biothreat agents. | granulysin is a cationic protein produced by human t cells and natural killer cells that can kill bacterial pathogens through disruption of microbial membrane integrity. herein we demonstrate antimicrobial activity of the granulysin peptide derived from the active site against bacillus anthracis, yersinia pestis, francisella tularensis, and burkholderia mallei, and show pathogen-specific differences in granulysin peptide effects. the susceptibility of y. pestis to granulysin is temperature depen ... | 2009 | 19587798 |
| correlates of environmental factors and human plague: an ecological study in vietnam. | human plague caused by yersinia pestis remains a public health threat in endemic countries, because the disease is associated with increased risk of mortality and severe economic and social consequences. during the past 10 years, outbreaks of plague have occasionally occurred in vietnam's central highlands region. the present study sought to describe and analyse the occurrence of plague and its association with ecological factors. | 2009 | 19584125 |
| comparative genomics of the emerging human pathogen photorhabdus asymbiotica with the insect pathogen photorhabdus luminescens. | the gram-negative bacterium photorhabdus asymbiotica (pa) has been recovered from human infections in both north america and australia. recently, pa has been shown to have a nematode vector that can also infect insects, like its sister species the insect pathogen p. luminescens (pl). to understand the relationship between pathogenicity to insects and humans in photorhabdus we have sequenced the complete genome of pa strain atcc43949 from north america. this strain (formerly referred to as xenorh ... | 2009 | 19583835 |
| gr1+ cells control growth of yopm-negative yersinia pestis during systemic plague. | yopm, a protein toxin of yersinia pestis, is necessary for virulence in a mouse model of systemic plague. we previously reported yopm-dependent natural killer (nk) cell depletion from blood and spleen samples of infected mice. however, in this study we found that infection with y. pestis kim5 (yopm(+)) caused depletion of nk cells in the spleen, but not in the liver, and antibody-mediated ablation of nk cells had no effect on bacterial growth. there was no yopm-associated effect on the percentag ... | 2009 | 19581396 |
| [the plague of the third pandemic and its current remergence]. | the reappearance of the plague in the 19th century, in what is generally referred to as the third pandemic, brought back painful memories of the great plague outbreaks of the past that had killed tens of millions of people. at the same time, this new pandemic opened the era of great discoveries, such as identification of the yersinia pestis bacterium, of transmission vectors and the first effective treatments. with these advances it became possible to control a disease which had, because of prog ... | 2008 | 19579344 |
| [role of burrow microbiocenosis in plague enzootia]. | the paper analyzes relationships of the plague bacilli to the representatives of different types of living organisms inhabiting the burrows. the authors give their own data on the qualitative and quantitative composition of indicoles of the burrow of little sousliks (spermophillus pygmaeus). they assess the role of mutagenic agents in burrow microbiocenoses. | 2009 | 19566065 |
| [study on the pathogen of plague in sanjiangyuan area in qinghai province]. | to study the biological characteristics of yersinia pestis and to develop prevention and control program on plague in sanjiangyuan areas, qinghai province. | 2009 | 19565850 |
| spatial analysis of plague in california: niche modeling predictions of the current distribution and potential response to climate change. | plague, caused by the bacterium yersinia pestis, is a public and wildlife health concern in california and the western united states. this study explores the spatial characteristics of positive plague samples in california and tests maxent, a machine-learning method that can be used to develop niche-based models from presence-only data, for mapping the potential distribution of plague foci. maxent models were constructed using geocoded seroprevalence data from surveillance of california ground s ... | 2009 | 19558717 |
| comparison of five commercial dna extraction kits for the recovery of yersinia pestis dna from bacterial suspensions and spiked environmental samples. | to evaluate commercial dna extraction kits for their ability to isolate dna from yersinia pestis suspensions and spiked environmental samples. | 2010 | 19558466 |
| primary pneumonic plague contracted from a mountain lion carcass. | primary pneumonic plague is a rare but often fatal form of yersinia pestis infection that results from direct inhalation of bacteria and is potentially transmissible from person to person. we describe a case of primary pneumonic plague in a wildlife biologist who was found deceased in his residence 1 week after conducting a necropsy on a mountain lion. | 2009 | 19555287 |
| simultaneous detection of five biothreat agents in powder samples by a multiplexed suspension array. | a suspension array-based multiplexed immunoassay was developed for rapid, sensitive, specific, and simultaneous detection of multiple biothreat-associated agents in powder samples. the 5-plexed immunoassays using sets of 9-plexed coupled fluorescent beads were employed to simultaneously detect five representative biothreat agents, including b. anthracis spore, y. pestis, sars-cov, staphylococcal enterotoxin b (seb) and ricin from a single powder sample and the feasibility for field samples was d ... | 2009 | 19555207 |
| the activities of the yersinia protein kinase a (ypka) and outer protein j (yopj) virulence factors converge on an eif2alpha kinase. | the yersinia protein kinase a (ypka) and outer protein j (yopj) are co-expressed from a single transcript and are injected directly into eukaryotic cells by the plague bacterium yersinia pestis. when overexpressed in vertebrate or yeast cells, ypka disrupts the actin-based cytoskeletal system by an unknown mechanism, whereas yopj obstructs inductive chemokine expression by inhibiting mapk and nf-kappab signaling. previously, we showed that the fission yeast schizosaccharomyces pombe was sensitiv ... | 2009 | 19553678 |
| characterization of zur-dependent genes and direct zur targets in yersinia pestis. | the zinc uptake regulator zur is a zn2+-sensing metalloregulatory protein involved in the maintenance of bacterial zinc homeostasis. up to now, regulation of zinc homeostasis by zur is poorly understood in y. pestis. | 2009 | 19552825 |
| how yersinia pestis becomes a foreign obstruction in the digestive system of the macrophage. | 2009 | 19550144 | |
| genotyping and phylogenetic analysis of yersinia pestis by mlva: insights into the worldwide expansion of central asia plague foci. | the species yersinia pestis is commonly divided into three classical biovars, antiqua, medievalis, and orientalis, belonging to subspecies pestis pathogenic for human and the (atypical) non-human pathogenic biovar microtus (alias pestoides) including several non-pestis subspecies. recent progress in molecular typing methods enables large-scale investigations in the population structure of this species. it is now possible to test hypotheses about its evolution which were proposed decades ago. for ... | 2009 | 19543392 |
| yersinia pestis endowed with increased cytotoxicity is avirulent in a bubonic plague model and induces rapid protection against pneumonic plague. | an important virulence strategy evolved by bacterial pathogens to overcome host defenses is the modulation of host cell death. previous observations have indicated that yersinia pestis, the causative agent of plague disease, exhibits restricted capacity to induce cell death in macrophages due to ineffective translocation of the type iii secretion effector yopj, as opposed to the readily translocated yopp, the yopj homologue of the enteropathogen yersinia enterocolitica oratio8. this led us to su ... | 2009 | 19529770 |
| [comparative analysis of distribution of pseudogenes in the genome of strains of basic and supplementary species of the plague infection agent]. | comparative analysis of distribution of pseudogenes (ypo1582, ypo1728, ypo1967, and ypo4008) of strains of basic and supplementary species of the plague infection agent and pseudotuberculosis infection agent was performed. the genome of basic subspecies of plague infection agent species strain contains 3 different variants: intact genes, genes with is-element inserts, or individual fragments. the pseudogene profile can be used as genetic marker of the y. pestis strains of basic subspecies from n ... | 2009 | 19522066 |
| clustered regularly interspaced short palindromic repeats (crisprs) for the genotyping of bacterial pathogens. | clustered regularly interspaced short palindromic repeats (crisprs) are dna sequences composed of a succession of repeats (23- to 47-bp long) separated by unique sequences called spacers. polymorphism can be observed in different strains of a species and may be used for genotyping. we describe protocols and bioinformatics tools that allow the identification of crisprs from sequenced genomes, their comparison, and their component determination (the direct repeats and the spacers). a schematic rep ... | 2009 | 19521870 |
| a review of plague persistence with special emphasis on fleas. | sylvatic plague is highly prevalent during infrequent epizootics that ravage the landscape of western north america. during these periods, plague dissemination is very efficient. epizootics end when rodent and flea populations are decimated and vectored transmission declines. a second phase (enzootic plague) ensues when plague is difficult to detect from fleas, hosts or the environment, and presents less of a threat to public health. recently, researchers have hypothesized that the bacterium (ye ... | 2009 | 19502688 |
| effects of weather and plague-induced die-offs of prairie dogs on the fleas of northern grasshopper mice. | plague, the disease caused by the bacterium yersinia pestis, can have devastating impacts on black-tailed prairie dogs (cynomys ludovicianus ord). other mammal hosts living on prairie dog colonies may be important in the transmission and maintenance of plague. we examined the flea populations of northern grasshopper mice (onychomys leucogaster wied) before, during, and after plague epizootics in northern colorado and studied the influence of host and environmental factors on flea abundance patte ... | 2009 | 19496431 |
| flea abundance on black-tailed prairie dogs (cynomys ludovicianus) increases during plague epizootics. | black-tailed prairie dogs (cynomys ludovicianus) on the great plains of the united states are highly susceptible to plague, caused by the bacterium yersinia pestis, with mortality on towns during plague epizootics often approaching 100%. the ability of flea-borne transmission to sustain disease spread has been questioned because of inefficiency of flea vectors. however, even with low individual efficiency, overall transmission can be increased if flea abundance (the number of fleas on hosts) inc ... | 2009 | 19492944 |
| comparative genomics of the inca/c multidrug resistance plasmid family. | multidrug resistance (mdr) plasmids belonging to the inca/c plasmid family are widely distributed among salmonella and other enterobacterial isolates from agricultural sources and have, at least once, also been identified in a drug-resistant yersinia pestis isolate (ip275) from madagascar. here, we present the complete plasmid sequences of the inca/c reference plasmid pra1 (143,963 bp), isolated in 1971 from the fish pathogen aeromonas hydrophila, and of the cryptic inca/c plasmid prax (49,763 b ... | 2009 | 19482926 |
| the single substitution i259t, conserved in the plasminogen activator pla of pandemic yersinia pestis branches, enhances fibrinolytic activity. | the outer membrane plasminogen activator pla of yersinia pestis is a central virulence factor in plague. the primary structure of the pla beta-barrel is conserved in y. pestis biovars antiqua, medievalis, and orientalis, which are associated with pandemics of plague. the pla molecule of the ancestral y. pestis lineages microtus and angola carries the single amino acid change t259i located in surface loop 5 of the beta-barrel. recombinant y. pestis kim d34 or escherichia coli xl1 expressing pla t ... | 2009 | 19465664 |
| [development of a multiplex pcr-suspension array for simultaneous detection of five bioterrorism bacteria]. | to develop a rapid, high-throughput screening method of gene suspension array technique to simultaneously detect five bioterrorism bacteria: bacillus anthracis, francisella tularensis, yersinia pestis, brucella spp. and burkholderia pseudomallei. | 2009 | 19462919 |
| plants as biofactories for the production of subunit vaccines against bio-security-related bacteria and viruses. | the development of new generation vaccines is an imperative tool to counteract accidental or intended release of bio-threat agents, such as bacillus anthracis, yersinia pestis and variola virus, and to control natural outbreaks. in the past few years, numerous data accumulated on the immunogenicity and safety of plant-made vaccines against bio-security-related organisms. in addition, expression levels achieved for these antigenic proteins are practical for the production of sufficient material f ... | 2009 | 19460602 |
| [effect of serotonin and dopamine on growth of yersinia pestis and francisella tularensis strains]. | to study the effects of serotonin and dophamine on the growth of yersinia pestis and francisella tularensis strains as well as ability of monoamines to change susceptibility of experimental animals to plague infection. | 2009 | 19459486 |
| genotyping of indian yersinia pestis strains by mlva and repetitive dna sequence based pcrs. | india experienced two plague outbreaks in gujarat and maharastra during 1994 and then in the shimla district of himachal pradesh during 2002. yersinia pestis strains recovered from rodents and pneumonic patients during the 1994 outbreaks, pneumonic patients from the 2002 shimla outbreak and rodents trapped on the deccan plateau during a surveillance activity carried out in 1998 were characterized by mlva, eric-pcr and eric-box-pcr. mlva genotyping of indian y. pestis strains revealed strains of ... | 2009 | 19449123 |
| [first internal workshop of the reference services at centro de pesquisas aggeu magalhães, fundação oswaldo cruz]. | 2009 | 19448951 | |
| growth of calcium-blind mutants of yersinia pestis at 37 degrees c in permissive ca2+-deficient environments. | cells of wild-type yersinia pestis exhibit a low-calcium response (lcr) defined as bacteriostasis with expression of a pcd-encoded type iii secretion system (t3ss) during cultivation at 37 degrees c without added ca(2+) versus vegetative growth with downregulation of the t3ss with ca(2+) (>or=2.5 mm). bacteriostasis is known to reflect cumulative toxicity of na(+), l-glutamic acid and culture ph; control of these variables enables full-scale growth ('rescue') in the absence of ca(2+). several t3 ... | 2009 | 19443541 |
| inactivation of avirulent yersinia pestis in butterfield's phosphate buffer and frankfurters by uvc (254 nm) and gamma radiation. | yersinia pestis is the causative agent of plague. although rare, pharyngeal plague in humans has been associated with consumption or handling of meat prepared from infected animals. the risks of contracting plague from consumption of deliberately contaminated food are currently unknown. gamma radiation is a penetrating form of electromagnetic radiation, and uvc radiation is used for decontamination of liquids or food surfaces. gamma radiation d10-values (the radiation dose needed to inactivate 1 ... | 2009 | 19435223 |
| pleiotropic effects of the lpxm mutation in yersinia pestis resulting in modification of the biosynthesis of major immunoreactive antigens. | deletion mutants in the lpxm gene in two yersinia pestis strains, the live russian vaccine strain ev niieg and a fully virulent strain, 231, synthesise a less toxic penta-acylated lipopolysaccharide (lps). analysis of these mutants revealed they possessed marked reductions in expression and immunoreactivity of numerous major proteins and carbohydrate antigens, including f1, pla, ymt, v antigen, lps, and eca. moreover, both mutants demonstrated altered epitope specificities of the antigens as det ... | 2009 | 19428838 |
| cpg oligodeoxynucleotides augment the murine immune response to the yersinia pestis f1-v vaccine in bubonic and pneumonic models of plague. | the current u.s. department of defense candidate plague vaccine is a fusion between two yersinia pestis proteins: the f1 capsular protein, and the low calcium response (lcr) v-protein. we hypothesized that an immunomodulator, such as cpg oligodeoxynucleotide (odn)s, could augment the immune response to the plague f1-v vaccine in a mouse model for plague. cpg odns significantly augmented the antibody response and efficacy of a single dose of the plague vaccine in murine bubonic and pneumonic mode ... | 2009 | 19428836 |
| are diffusion models too simple? a comparison with telegraph models of invasion. | diffusion models of animal movement are often criticized because they assume animals have infinite velocity and completely random motion. to investigate the impact of these assumptions, i compared a diffusion model with a telegraph model of dispersal the telegraph model assumes organisms have finite velocity and tend to maintain their direction. i compared the models in two settings: (i) as models for dispersal of nonreproducing organisms and (ii) as models for range expansion of organisms that ... | 1993 | 19425956 |
| genetic reductionist approach for dissecting individual roles of ggdef proteins within the c-di-gmp signaling network in salmonella. | bacteria have developed an exclusive signal transduction system involving multiple diguanylate cyclase and phosphodiesterase domain-containing proteins (ggdef and eal/hd-gyp, respectively) that modulate the levels of the same diffusible molecule, 3'-5'-cyclic diguanylic acid (c-di-gmp), to transmit signals and obtain specific cellular responses. current knowledge about c-di-gmp signaling has been inferred mainly from the analysis of recombinant bacteria that either lack or overproduce individual ... | 2009 | 19416883 |
| decreased time for detection and quantification of virulent bacillus anthracis and yersinia pestis using a bionanopore (bnp) membrane technology. | many aspects of biodefense research require quantitative growth assessments of the test agent. this study evaluated the bionanopore (bnp) technology to quantitate bacillus anthracis and yersinia pestis faster than traditional plate counting methods. the bnp technology enabled quantification of b. anthracis and y. pestis in phosphate-buffered saline and naïve rabbit blood at 6 and 24 h, respectively. after 6 h of growth, counts for b. anthracis ranged from 6.19-6.45 log(10) cfu ml(-1) on bnp, whi ... | 2009 | 19413803 |
| seeding-induced self-assembling protein nanowires dramatically increase the sensitivity of immunoassays. | aiming to build a supersensitive and easily operable immunoassay, bifunctional protein nanowires were generated by seeding-induced self-assembling of the yeast amyloid protein sup35p that genetically fused with protein g and an enzyme (methyl-parathion hydrolase, mph), respectively. the protein nanowires possessed a high ratio of enzyme molecules to protein g, allowing a dramatic increase of the enzymatic signal when protein g was bound to an antibody target. as a result, a 100-fold enhancement ... | 2009 | 19402649 |
| development and evaluation of two simple, rapid immunochromatographic tests for the detection of yersinia pestis antibodies in humans and reservoirs. | tools for plague diagnosis and surveillance are not always available and affordable in most of the countries affected by the disease. yersinia pestis isolation for confirmation is time-consuming and difficult to perform under field conditions. serologic tests like elisa require specific equipments not always available in developing countries. in addition to the existing rapid test for antigen detection, a rapid serodiagnostic assay may be useful for plague control. | 2009 | 19399164 |
| the yersinia pseudotuberculosis ypla phospholipase differs in its activity, regulation and secretion from that of the yersinia enterocolitica ypla. | analysis of the yersinia pseudotuberculosis and yersinia pestis genomes indicates that both species carry an identical copy of a gene that is predicted to encode a protein which shares 80% similarity to the yersinia enterocolitica ypla, a secreted phospholipase that has been shown to contribute to virulence. in contrast to well tolerated production of the y. enterocolitica ypla in escherichia coli, y. pseudotuberculosis ypla expression was found to be toxic; however, cell viability could be rest ... | 2009 | 19397992 |
| genome-scale reconstruction of the metabolic network in yersinia pestis, strain 91001. | the gram-negative bacterium yersinia pestis, the aetiological agent of bubonic plague, is one of the deadliest pathogens known to man. despite its historical reputation, plague is a modern disease which annually afflicts thousands of people. public safety considerations greatly limit clinical experimentation on this organism and thus development of theoretical tools to analyze the capabilities of this pathogen is of utmost importance. here, we report the first genome-scale metabolic model of yer ... | 2009 | 19396373 |
| [immunochemical characteristics of the autoagglutination factor of plague pathogen]. | immunochemical studies were performed to characterize the autoagglutination factor (af) isolated from the plasmid-free variant of yersinia pestis ev76 strains. the preparation based on the capsule cafl antigen isolated from the triplasmid variant of the same strain was used for comparison. af and cafl are the surface protein antigens of the plague pathogen, which are similar in their capacity for self-aggregation and in the molecular mass of a subunit (about 17 kda). however, unlike cafl, fa giv ... | 2009 | 19388480 |
| antigen-specific vgamma2vdelta2 t effector cells confer homeostatic protection against pneumonic plaque lesions. | the possibility that vgamma2vdelta2 t effector cells can confer protection against pulmonary infectious diseases has not been tested. we have recently demonstrated that single-dose (e)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (hmbpp) plus il-2 treatment can induce prolonged accumulation of vgamma2vdelta2 t effector cells in lungs. here, we show that a delayed hmbpp/il-2 administration after inhalational yersinia pestis infection induced marked expansion of vgamma2vdelta2 t cells but failed to ... | 2009 | 19383786 |
| [study of molecular mechanism of rheum offcinale against yersinia pestis]. | to investigate molecular mechanism of traditional chinese medicine rheum offcinale against yersinia pestis, whole genome dna microarray that contains 4005 annotated genes of y. pestis was used. the minimal inhibition concentration (mic) of r. offcinale extract against y. pestis was determined by liquid dilution method. the gene expression profile of y. pestis was performed after exposured to r. offcinale extract at a concentration of 10 x mic for 30 and 60 minutes. the total rna extracted and pu ... | 2009 | 19382460 |
| small protective fragments of the yersinia pestis v antigen. | yersinia pestis is the causative agent of plague. naturally occurring cases of the disease and the potential use of y. pestis as a bioweapon fuel the need for efficacious vaccines. the most recent plague vaccine is a killed whole cell preparation that is expensive to manufacture and its side effects are common. the protective antigens f1 and v have been identified and are currently being developed as a combined subunit vaccine. protective epitopes of the v antigen have previously been shown to r ... | 2009 | 19366573 |
| inactivation of yersinia pseudotuberculosis, as a surrogate for yersinia pestis, by liquid biocides in the presence of food residue. | the efficacy of liquid biocides is influenced by surface cleanliness, treatment time, and temperature. experiments were completed to measure the impact of these variables on the ability of commercial biocides to inactivate yersinia pseudotuberculosis atcc 29910, as a surrogate for yersinia pestis, in the presence of food residues. the test organism was mixed with water, milk, flour, or egg yolk and then dried onto stainless steel coupons. coupons were then exposed to sodium hypochlorite, acidifi ... | 2009 | 19350985 |
| [epizootological characteristics of the natural foci of plague in china: a review of literature]. | 2009 | 19350720 | |
| validation of cooking times and temperatures for thermal inactivation of yersinia pestis strains kim5 and cdc-a1122 in irradiated ground beef. | irradiated ground beef samples (ca. 3-g portions with ca. 25% fat) inoculated with yersina pestis strain kim5 (ca. 6.7 log cfu/g) were heated in a circulating water bath stabilized at 48.9, 50, 52.5, 55, 57.5, or 60 degrees c (120, 122, 126.5, 131, 135.5, and 140 degrees f, respectively). average d-values were 192.17, 34.38, 17.11, 3.87, 1.32, and 0.56 min, respectively, with a corresponding z-value of 4.67 degrees c (8.41 degrees f). in related experiments, irradiated ground beef patties (ca. 9 ... | 2009 | 19343945 |
| [influence of neutrophilokines on population and subpopulation repertoire of lymphocytes and their functional activity during immune response against plague]. | results of experimental study of regulatory effect of nutrophilokines induced by yersinia pestis ev strain on population and subpopulation repertoire of lymphocytes and their functional activity during immune response against plague infection are presented. it was established that these neutrophilokines stimulate cd4+ and suppress cd8+ lymphocytes. helper effect of neutrophilokines on functional activity of lymphocytes was more pronounced during secondary than during primary immune response. | 2009 | 19338236 |
| [conservation of the regulatory elements implicated in the control of the rpsb-tsf operon expression in gamma-proteobacteria]. | in eubacteria, the rpsb-tsf operon encodes two essential components of translational apparatus, ribosomal protein (r-protein) s2 and elongation factor ts. recently, we located the promoter region of the escherichia coli rpsb-tsf operon and demonstrated that both rpsb and tsf genes are negatively regulated by r-protein s2 at the translational level. in this paper, we present data of phylogenetic analysis showing high conservation of both the promoter signature and the structure of the 5'-untransl ... | 2009 | 19334533 |
| genomic evidence for the evolution of streptococcus equi: host restriction, increased virulence, and genetic exchange with human pathogens. | the continued evolution of bacterial pathogens has major implications for both human and animal disease, but the exchange of genetic material between host-restricted pathogens is rarely considered. streptococcus equi subspecies equi (s. equi) is a host-restricted pathogen of horses that has evolved from the zoonotic pathogen streptococcus equi subspecies zooepidemicus (s. zooepidemicus). these pathogens share approximately 80% genome sequence identity with the important human pathogen streptococ ... | 2009 | 19325880 |
| invited review: breaking barriers--attack on innate immune defences by omptin surface proteases of enterobacterial pathogens. | the omptin family of gram-negative bacterial transmembrane aspartic proteases comprises surface proteins with a highly conserved beta-barrel fold but differing biological functions. the omptins ompt of escherichia coli, pgte of salmonella enterica, and pla of yersinia pestis differ in their substrate specificity as well as in control of their expression. their functional differences are in accordance with the differing pathogenesis of the infections caused by e. coli, salmonella, and y. pestis, ... | 2009 | 19318417 |
| plant-derived recombinant f1, v, and f1-v fusion antigens of yersinia pestis activate human cells of the innate and adaptive immune system. | plague is still endemic in different regions of the world. current vaccines raise concern for their side effects and limited protection, highlighting the need for an efficacious and rapidly producible vaccine. f1 and v antigens of yersinia pestis, and f1-v fusion protein produced in nicotiana benthamiana administered to guinea pigs resulted in immunity and protection against an aerosol challenge of virulent y. pestis. we examined the effects of plant-derived f1, v, and f1-v on human cells of the ... | 2009 | 19309560 |
| evidence for the involvement of an alternate rodent host in the dynamics of introduced plague in prairie dogs. | 1. the introduction of plague to north america is a significant threat to colonies of prairie dogs (cynomys ludovicianus), a species of conservation concern in the great plains. other small rodents are exposed to the causative agent, yersinia pestis, during or after epizootics; yet, its effect on these rodents is not known, and their role in transmitting and maintaining plague in the absence of prairie dogs remains unclear. 2. we live-trapped small rodents and collected their fleas on 11 colonie ... | 2009 | 19302321 |
| incorporating time postinoculation into a dose-response model of yersinia pestis in mice. | to develop a time-dependent dose-response model for describing the survival of animals exposed to yersinia pestis. | 2009 | 19302316 |
| yersinia pestis can reside in autophagosomes and avoid xenophagy in murine macrophages by preventing vacuole acidification. | yersinia pestis survives and replicates in phagosomes of murine macrophages. previous studies demonstrated that y. pestis-containing vacuoles (ycvs) acquire markers of late endosomes or lysosomes in naïve macrophages and that this bacterium can survive in macrophages activated with the cytokine gamma interferon. an autophagic process known as xenophagy, which destroys pathogens in acidic autophagolysosomes, can occur in naïve macrophages and is upregulated in activated macrophages. studies were ... | 2009 | 19289509 |
| molecular darwinian evolution of virulence in yersinia pestis. | 2009 | 19289506 | |
| a strategy to verify the absence of the pgm locus in yersinia pestis strain candidates for select agent exemption. | yersinia pestis is a department of health and human services select agent as defined in federal regulations. certain attenuated strains of y. pestis, such as the pgm(-) strain, are exempt from these regulations. herein we describe a strategy to verify the absence of the pgm locus in y. pestis strains being considered as candidates for select agent exemption by pcr analysis of virulence-associated genes. | 2009 | 19281840 |
| [on pathogenetic significance of activation of lipid peroxidation in the mechanisms of disturbance of blood rheologic properties in experimental intoxication induced by fraction fii of vaccinal ev strain of y. pestis]. | changes of blood viscosity were induced by parenteral administration of fraction ii of vaccinal ev strain of y. pestis ("murine" toxin) to mice at doses equivalent to ld50 and ld25. the study revealed correlation between lipid peroxidation activity, severity of autointoxication, and integrated indices of blood theologic properties. | 2009 | 19280983 |