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phage-based platforms for the clinical detection of human bacterial pathogens.bacteriophages (phages) have been utilized for decades as a means for uniquely identifying their target bacteria. due to their inherent natural specificity, ease of use, and straightforward production, phage possess a number of desirable attributes which makes them particularly suited as bacterial detectors. as a result, extensive research has been conducted into the development of phage, or phage-derived products to expedite the detection of human pathogens. however, very few phage-based diagno ...201223050221
hfq regulates biofilm gut blockage that facilitates flea-borne transmission of yersinia pestis.the plague bacillus yersinia pestis can achieve transmission by biofilm blockage of the foregut proventriculus of its flea vector. hfq is revealed to be essential for biofilm blockage formation and acquisition and fitness of y. pestis during flea gut infection, consistent with posttranscriptional regulatory mechanisms in plague transmission.201222328669
prioritizing risks and uncertainties from intentional release of selected category a pathogens.this paper synthesizes available information on five category a pathogens (bacillus anthracis, yersinia pestis, francisella tularensis, variola major and lassa) to develop quantitative guidelines for how environmental pathogen concentrations may be related to human health risk in an indoor environment. an integrated model of environmental transport and human health exposure to biological pathogens is constructed which 1) includes the effects of environmental attenuation, 2) considers fomite cont ...201222412915
development and comparison of two assay formats for parallel detection of four biothreat pathogens by using suspension microarrays.microarrays provide a powerful analytical tool for the simultaneous detection of multiple pathogens. we developed diagnostic suspension microarrays for sensitive and specific detection of the biothreat pathogens bacillus anthracis, yersinia pestis, francisella tularensis and coxiella burnetii. two assay chemistries for amplification and labeling were developed, one method using direct hybridization and the other using target-specific primer extension, combined with hybridization to universal arr ...201222355407
yopp-expressing variant of y. pestis activates a potent innate immune response affording cross-protection against yersiniosis and tularemia [corrected].plague, initiated by yersinia pestis infection, is a rapidly progressing disease with a high mortality rate if not quickly treated. the existence of antibiotic-resistant y. pestis strains emphasizes the need for the development of novel countermeasures against plague. we previously reported the generation of a recombinant y. pestis strain (kim53δj+p) that over-expresses y. enterocolitica yopp. when this strain was administered subcutaneously to mice, it elicited a fast and effective protective i ...201324358292
simultaneous and rapid detection of salmonella typhi, bacillus anthracis, and yersinia pestis by using multiplex polymerase chain reaction (pcr).salmonella typhi, bacillus anthracis, and yersinia pestis are some serious human pathogens, which their early diagnosis is of great importance. salmonella typhi, bacillus anthracis, and yersinia pestis cause typhoid fever, anthrax, and plague respectively. these bacteria can be used to make biologic weapons.201324719692
customizable pcr-microplate array for differential identification of multiple pathogens.customizable pcr-microplate arrays were developed for the rapid identification of salmonella typhimurium, salmonella saintpaul, salmonella typhi, shigella dysenteriae, escherichia coli o157:h7, francisella tularensis subsp. tularensis, francisella tularensis subsp. novicida, vibrio cholerae, vibrio parahaemolyticus, yersinia pestis, and yersinia pseudotuberculosis. previously, we identified highly specific primers targeting each of these pathogens. here, we report the development of customizable ...201324215700
reverse transcription-pcr-electrospray ionization mass spectrometry for rapid detection of biothreat and common respiratory pathogens.electrospray ionization mass spectrometry (esi-ms) analysis of reverse transcription (rt)-pcr amplicons from human respiratory samples allows for broad pathogen identification approximately 8 h after collection. we investigated the performance characteristics of a high-throughput rt-pcr-coupled esi-ms assay for distinguishing biothreat (bt) agents from common bacterial, fungal, and viral respiratory pathogens in bronchoalveolar lavage (bal) fluid specimens from subjects with suspected respirator ...201323903543
features of variable number of tandem repeats in yersinia pestis and the development of a hierarchical genotyping scheme.variable number of tandem repeats (vntrs) that are widely distributed in the genome of yersinia pestis proved to be useful markers for the genotyping and source-tracing of this notorious pathogen. in this study, we probed into the features of vntrs in the y. pestis genome and developed a simple hierarchical genotyping system based on optimized vntr loci.201323805236
intranasal prophylaxis with cpg oligodeoxynucleotide can protect against yersinia pestis infection.immunomodulatory agents potentially represent a new class of broad-spectrum antimicrobials. here, we demonstrate that prophylaxis with immunomodulatory cytosine-phosphate-guanidine (cpg) oligodeoxynucleotide (odn), a toll-like receptor 9 (tlr9) agonist, confers protection against yersinia pestis, the etiologic agent of plague. the data establish that intranasal administration of cpg odn 1 day prior to lethal pulmonary exposure to y. pestis strain kim d27 significantly improves survival of c57bl/ ...201323545300
structural modifications of bacterial lipopolysaccharide that facilitate gram-negative bacteria evasion of host innate immunity.bacterial lipopolysaccharide (lps), a cell wall component characteristic of gram-negative bacteria, is a representative pathogen-associated molecular pattern that allows mammalian cells to recognize bacterial invasion and trigger innate immune responses. the polysaccharide moiety of lps primary plays protective roles for bacteria such as prevention from complement attacks or camouflage with common host carbohydrate residues. the lipid moiety, termed lipid a, is recognized by the toll-like recept ...201323745121
francisella tularensis subsp. tularensis induces a unique pulmonary inflammatory response: role of bacterial gene expression in temporal regulation of host defense responses.pulmonary exposure to francisella tularensis is associated with severe lung pathology and a high mortality rate. the lack of induction of classical inflammatory mediators, including il1-β and tnf-α, during early infection has led to the suggestion that f. tularensis evades detection by host innate immune surveillance and/or actively suppresses inflammation. to gain more insight into the host response to francisella infection during the acute stage, transcriptomic analysis was performed on lung t ...201323690939
development of a panel of recombinase polymerase amplification assays for detection of biothreat agents.syndromic panels for infectious disease have been suggested to be of value in point-of-care diagnostics for developing countries and for biodefense. to test the performance of isothermal recombinase polymerase amplification (rpa) assays, we developed a panel of 10 rpas for biothreat agents. the panel included rpas for francisella tularensis, yersinia pestis, bacillus anthracis, variola virus, and reverse transcriptase rpa (rt-rpa) assays for rift valley fever virus, ebola virus, sudan virus, and ...201323345286
pathogenicity of yersinia pestis synthesis of 1-dephosphorylated lipid a.synthesis of escherichia coli lpxl, which transfers a secondary laurate chain to the 2' position of lipid a, in yersinia pestis produced bisphosphoryl hexa-acylated lipid a at 37°c, leading to significant attenuation of virulence. our previous observations also indicated that strain χ10015(pcd1ap) (δlpxp32::p(lpxl) lpxl) stimulated a strong inflammatory reaction but sickened mice before recovery and retained virulence via intranasal (i.n.) infection. the development of live, attenuated y. pestis ...201323357387
the kdpd/kdpe two-component system: integrating k⁺ homeostasis and virulence.the two-component system (tcs) kdpd/kdpe, extensively studied for its regulatory role in potassium (k(+)) transport, has more recently been identified as an adaptive regulator involved in the virulence and intracellular survival of pathogenic bacteria, including staphylococcus aureus, entero-haemorrhagic escherichia coli, salmonella typhimurium, yersinia pestis, francisella species, photorhabdus asymbiotica, and mycobacteria. key homeostasis requirements monitored by kdpd/kdpe and other tcss suc ...201323555240
evaluation of the filmarray® system for detection of bacillus anthracis, francisella tularensis and yersinia pestis.to evaluate the sensitivity and specificity of the biofire diagnostics filmarray(®) system in combination with their biothreat panel for the detection of bacillus anthracis (ba), francisella tularensis (ft) and yersinia pestis (yp) dna, and demonstrate the detection of ba spores.201323279070
kinetic characterization and allosteric inhibition of the yersinia pestis 1-deoxy-d-xylulose 5-phosphate reductoisomerase (mep synthase).the methylerythritol phosphate (mep) pathway found in many bacteria governs the synthesis of isoprenoids, which are crucial lipid precursors for vital cell components such as ubiquinone. because mammals synthesize isoprenoids via an alternate pathway, the bacterial mep pathway is an attractive target for novel antibiotic development, necessitated by emerging antibiotic resistance as well as biodefense concerns. the first committed step in the mep pathway is the reduction and isomerization of 1-d ...201425171339
rapid detection and simultaneous antibiotic susceptibility analysis of yersinia pestis directly from clinical specimens by use of reporter phage.yersinia pestis is a tier 1 agent due to its contagious pneumopathogenicity, extremely rapid progression, and high mortality rate. as the disease is usually fatal without appropriate therapy, rapid detection from clinical matrices is critical to patient outcomes. we previously engineered the diagnostic phage φa1122 with luxab to create a "light-tagged" reporter phage. φa1122::luxab rapidly detects y. pestis in pure culture and human serum by transducing a bioluminescent signal response. in this ...201424920765
type iii secretion needle proteins induce cell signaling and cytokine secretion via toll-like receptors.pathogens are recognized by hosts by use of various receptors, including the toll-like receptor (tlr) and nod-like receptor (nlr) families. ligands for these varied receptors, including bacterial products, are identified by the immune system, resulting in development of innate immune responses. only a couple of components from type iii secretion (t3s) systems are known to be recognized by tlr or nlr family members. known t3s components that are detected by pattern recognition receptors (prrs) ar ...201424643544
new insights into how yersinia pestis adapts to its mammalian host during bubonic plague.bubonic plague (a fatal, flea-transmitted disease) remains an international public health concern. although our understanding of the pathogenesis of bubonic plague has improved significantly over the last few decades, researchers have still not been able to define the complete set of y. pestis genes needed for disease or to characterize the mechanisms that enable infection. here, we generated a library of y. pestis mutants, each lacking one or more of the genes previously identified as being up- ...201424675805
metabolic network analysis-based identification of antimicrobial drug targets in category a bioterrorism agents.the 2001 anthrax mail attacks in the united states demonstrated the potential threat of bioterrorism, hence driving the need to develop sophisticated treatment and diagnostic protocols to counter biological warfare. here, by performing flux balance analyses on the fully-annotated metabolic networks of multiple, whole genome-sequenced bacterial strains, we have identified a large number of metabolic enzymes as potential drug targets for each of the three category a-designated bioterrorism agents ...201424454817
inactivation of peroxiredoxin 6 by the pla protease of yersinia pestis.pneumonic plague represents the most severe form of disease caused by yersinia pestis due to its ease of transmission, rapid progression, and high mortality rate. the y. pestis outer membrane pla protease is essential for the development of pneumonic plague; however, the complete repertoire of substrates cleaved by pla in the lungs is not known. in this study, we describe a proteomic screen to identify host proteins contained within the bronchoalveolar lavage fluid of mice that are cleaved and/o ...201526553463
susceptibility of select agents to predation by predatory bacteria.select agents are microorganisms and toxins considered to be exploitable as biological weapons. although infections by many select agents can be treated by conventional antibiotics, the risk of an emerging or engineered drug resistant strain is of great concern. one group of microorganisms that is showing potential to control drug resistant gram-negative bacteria are the predatory bacteria from the genera bdellovibrio spp. and micavibrio spp. in this study, we have examined the ability of bdello ...201527682124
investigation of yersinia pestis laboratory adaptation through a combined genomics and proteomics approach.the bacterial pathogen yersinia pestis, the cause of plague in humans and animals, normally has a sylvatic lifestyle, cycling between fleas and mammals. in contrast, laboratory-grown y. pestis experiences a more constant environment and conditions that it would not normally encounter. the transition from the natural environment to the laboratory results in a vastly different set of selective pressures, and represents what could be considered domestication. understanding the kinds of adaptations ...201526599979
development of a bead-based luminex assay using lipopolysaccharide specific monoclonal antibodies to detect biological threats from brucella species.brucella, a gram-negative bacterium, is classified as a potential bioterrorism agent mainly due to the low dose needed to cause infection and the ability to transmit the bacteria via aerosols. goats/sheep, cattle, pigs, dogs, sheep and rodents are infected by b. melitensis, b. abortus, b. suis, b. canis, b. ovis and b. neotomae, respectively, the six classical brucella species. most human cases are caused by b. melitensis and b. abortus. our aim was to specifically detect brucellae with 'smooth' ...201526438077
prevalence and distribution of soil-borne zoonotic pathogens in lahore district of pakistan.a multidisciplinary, collaborative project was conducted to determine the prevalence and distribution of soil-borne zoonotic pathogens in lahore district of pakistan and ascertain its public health significance. using a grid-based sampling strategy, soil samples (n = 145) were collected from villages (n = 29, 5 samples/village) and examined for bacillus anthracis, burkholderia mallei/pseudomallei, coxiella burnetii, francisella tularensis, and yersinia pestis using real time pcr assays. chemical ...201526441860
identification of highly pathogenic microorganisms by matrix-assisted laser desorption ionization-time of flight mass spectrometry: results of an interlaboratory ring trial.in the case of a release of highly pathogenic bacteria (hpb), there is an urgent need for rapid, accurate, and reliable diagnostics. maldi-tof mass spectrometry is a rapid, accurate, and relatively inexpensive technique that is becoming increasingly important in microbiological diagnostics to complement classical microbiology, pcr, and genotyping of hpb. in the present study, the results of a joint exercise with 11 partner institutions from nine european countries are presented. in this exercise ...201526063856
preliminary survey of ectoparasites and associated pathogens from norway rats in new york city.the norway rat (rattus norvegicus) is a reservoir of many zoonotic pathogens and lives in close proximity to humans in urban environments. human infection with rodent-borne disease occurs either directly through contact with a rat or its excreta, or indirectly via arthropod vectors such as fleas and ticks. here, we report on the diversity and abundance of ectoparasitic arthropod species and associated pathogenic bacteria from 133 norway rats trapped over a 10-mo period in manhattan, new york, ny ...201526336309
targeted next-generation sequencing for the detection of ciprofloxacin resistance markers using molecular inversion probes.antibiotic resistance (ar) is an epidemic of increasing magnitude requiring rapid identification and profiling for appropriate and timely therapeutic measures and containment strategies. in this context, ciprofloxacin is part of the first-line of countermeasures against numerous high consequence bacteria. significant resistance can occur via single nucleotide polymorphisms (snp) and deletions within ciprofloxacin targeted genes. ideally, use of ciprofloxacin would be prefaced with ar determinati ...201627174456
genetic variation at the mhc drb1 locus is similar across gunnison's prairie dog (cynomys gunnisoni) colonies regardless of plague history.yersinia pestis was introduced to north america around 1900 and leads to nearly 100% mortality in prairie dog (cynomys spp.) colonies during epizootic events, which suggests this pathogen may exert a strong selective force. we characterized genetic diversity at an mhc class ii locus (drb1) in gunnison's prairie dog (c. gunnisoni) and quantified population genetic structure at the drb1 versus 12 microsatellite loci in three large arizona colonies. two colonies, seligman (se) and espee ranch (es), ...201627066243
development of liposomal ciprofloxacin to treat lung infections.except for management of pseudomonas aeruginosa (pa) in cystic fibrosis, there are no approved inhaled antibiotic treatments for any other diseases or for infections from other pathogenic microorganisms such as tuberculosis, non-tuberculous mycobacteria, fungal infections or potential inhaled biowarfare agents including francisella tularensis, yersinia pestis and coxiella burnetii (which cause pneumonic tularemia, plague and q fever, respectively). delivery of an antibiotic formulation via the i ...201626938551
rational considerations about development of live attenuated yersinia pestis vaccines.the risk of plague as a bioweapon has prompted increasing research efforts to develop plague vaccines due to its extreme virulence and the ease of its transmission. subunit vaccines that contain f1 and lcrv antigens of y. pestis have been tested for safety and immunogenicity, but doubts have been raised about whether subunit vaccines that engender antibody responses will protect against pneumonic plague, which requires both humeral and cellular immune responses for protection. the live, attenuat ...201424372254
kdo hydroxylase is an inner core assembly enzyme in the ko-containing lipopolysaccharide biosynthesis.the lipopolysaccharide (lps) isolated from certain important gram-negative pathogens including a human pathogen yersinia pestis and opportunistic pathogens burkholderia mallei and burkholderia pseudomallei contains d-glycero-d-talo-oct-2-ulosonic acid (ko), an isosteric analog of 3-deoxy-d-manno-oct-2-ulosonic acid (kdo). kdo 3-hydroxylase (kdoo), a fe(2+)/α-kg/o2 dependent dioxygenase from burkholderia ambifaria and yersinia pestis is responsible for ko formation with kdo2-lipid a as a substrat ...201425204504
hfq-dependent, co-ordinate control of cyclic diguanylate synthesis and catabolism in the plague pathogen yersinia pestis.yersinia pestis, the cause of the disease plague, forms biofilms to enhance flea-to-mammal transmission. biofilm formation is dependent on exopolysaccharide synthesis and is controlled by the intracellular levels of the second messenger molecule cyclic diguanylate (c-di-gmp), but the mechanisms by which y. pestis regulates c-di-gmp synthesis and turnover are not fully understood. here we show that the small rna chaperone hfq contributes to the regulation of c-di-gmp levels and biofilm formation ...201222924957
the hemophore hasa from yersinia pestis (hasayp) coordinates hemin with a single residue, tyr75, and with minimal conformational change.hemophores from serratia marcescens (hasa(sm)) and pseudomonas aeruginosa (hasa(p)) bind hemin between two loops, which harbor the axial ligands h32 and y75. hemin binding to the y75 loop triggers closing of the h32 loop and enables binding of h32. because yersinia pestis hasa (hasa(yp)) presents a gln at position 32, we determined the structures of apo- and holo-hasa(yp). surprisingly, the q32 loop in apo-hasa(yp) is already in the closed conformation, but no residue from the q32 loop binds hem ...201323578210
retracing the evolutionary path that led to flea-borne transmission of yersinia pestis.yersinia pestis is an arthropod-borne bacterial pathogen that evolved recently from yersinia pseudotuberculosis, an enteric pathogen transmitted via the fecal-oral route. this radical ecological transition can be attributed to a few discrete genetic changes from a still-extant recent ancestor, thus providing a tractable case study in pathogen evolution and emergence. here, we determined the genetic and mechanistic basis of the evolutionary adaptation of y. pestis to flea-borne transmission. rema ...201424832452
the role of transition metal transporters for iron, zinc, manganese, and copper in the pathogenesis of yersinia pestis.yersinia pestis, the causative agent of bubonic, septicemic and pneumonic plague, encodes a multitude of fe transport systems. some of these are defective due to frameshift or is element insertions, while others are functional in vitro but have no established role in causing infections. indeed only 3 fe transporters (ybt, yfe and feo) have been shown to be important in at least one form of plague. the yersiniabactin (ybt) system is essential in the early dermal/lymphatic stages of bubonic plague ...201525891079
context-dependent protein folding of a virulence peptide in the bacterial and host environments: structure of an sych-yoph chaperone-effector complex.yersinia pestis injects numerous bacterial proteins into host cells through an organic nanomachine called the type 3 secretion system. one such substrate is the tyrosine phosphatase yoph, which requires an interaction with a cognate chaperone in order to be effectively injected. here, the first crystal structure of a sych-yoph complex is reported, determined to 1.9 å resolution. the structure reveals the presence of (i) a nonglobular polypeptide in yoph, (ii) a so-called β-motif in yoph and (iii ...201323519663
role of tellurite resistance operon in filamentous growth of yersinia pestis in macrophages.yersinia pestis initiates infection by parasitism of host macrophages. in response to macrophage infections, intracellular y. pestis can assume a filamentous cellular morphology which may mediate resistance to host cell innate immune responses. we previously observed the expression of y. pestis tellurite resistance proteins terd and tere from the terzabcde operon during macrophage infections. others have observed a filamentous response associated with expression of tellurite resistance operon in ...201526536670
genome-wide analysis of small rnas expressed by yersinia pestis identifies a regulator of the yop-ysc type iii secretion system.small noncoding rna (srna) molecules are integral components of the regulatory machinery for many bacterial species and are known to posttranscriptionally regulate metabolic and stress-response pathways, quorum sensing, virulence factors, and more. the yop-ysc type iii secretion system (t3ss) is a critical virulence component for the pathogenic yersinia species, and the regulation of this system is tightly controlled at each step from transcription to translocation of effectors into host cells. ...201424532772
crp is an activator of yersinia pestis biofilm formation that operates via a mechanism involving gmha and waaae-coad.gmha encodes a phosphoheptose isomerase that catalyzes the biosynthesis of heptose, a conserved component of lipopolysaccharide (lps). gmha plays an important role in yersinia pestis biofilm blockage in the flea gut. waaa, waae, and coad constitute a three-gene operon waaae-coad in y. pestis. waaa encodes a transferase that is responsible for binding lipid-a to the core oligosaccharide of lps. waaa is a key determinant in y. pestis biofilm formation, and the waaa expression is positively regulat ...201627014218
analysis of autoinducer-2 quorum sensing in yersinia pestis.the autoinducer-2 (ai-2) quorum-sensing system has been linked to diverse phenotypes and regulatory changes in pathogenic bacteria. in the present study, we performed a molecular and biochemical characterization of the ai-2 system in yersinia pestis, the causative agent of plague. in strain co92, the ai-2 signal is produced in a luxs-dependent manner, reaching maximal levels of 2.5 μm in the late logarithmic growth phase, and both wild-type and pigmentation (pgm) mutant strains made equivalent l ...201323959719
high-throughput, signature-tagged mutagenic approach to identify novel virulence factors of yersinia pestis co92 in a mouse model of infection.the identification of new virulence factors in yersinia pestis and understanding their molecular mechanisms during an infection process are necessary in designing a better vaccine or to formulate an appropriate therapeutic intervention. by using a high-throughput, signature-tagged mutagenic approach, we created 5,088 mutants of y. pestis strain co92 and screened them in a mouse model of pneumonic plague at a dose equivalent to 5 50% lethal doses (ld50) of wild-type (wt) co92. from this screen, w ...201525754198
structural snapshots along the reaction pathway of yersinia pestis ripa, a putative butyryl-coa transferase.yersinia pestis, the causative agent of bubonic plague, is able to survive in both extracellular and intracellular environments within the human host, although its intracellular survival within macrophages is poorly understood. a novel y. pestis three-gene rip (required for intracellular proliferation) operon, and in particular ripa, has been shown to be essential for survival and replication in interferon γ-induced macrophages. ripa was previously characterized as a putative butyryl-coa transfe ...201424699651
early sensing of yersinia pestis airway infection by bone marrow cells.bacterial infection of the lungs triggers a swift innate immune response that involves the production of cytokines and chemokines that promote recruitment of immune cells from the bone marrow (bm) into the infected tissue and limit the ability of the pathogen to replicate. recent in vivo studies of pneumonic plague in animal models indicate that the pulmonary pro-inflammatory response to airway infection with yersinia pestis is substantially delayed in comparison to other pathogens. consequently ...201223189271
yopj-induced caspase-1 activation in yersinia-infected macrophages: independent of apoptosis, linked to necrosis, dispensable for innate host defense.yersinia outer protein j (yopj) is a type iii secretion system (t3ss) effector of pathogenic yersinia (yersinia pestis, yersinia enterocolitica and yersinia pseudotuberculosis) that is secreted into host cells. yopj inhibits survival response pathways in macrophages, causing cell death. allelic variation of yopj is responsible for differential cytotoxicity in yersinia strains. yopj isoforms in y. enterocolitica o:8 (yopp) and y. pestis kim (yopj(kim)) strains have high cytotoxic activity. in add ...201222563435
early host cell targets of yersinia pestis during primary pneumonic plague.inhalation of yersinia pestis causes primary pneumonic plague, a highly lethal syndrome with mortality rates approaching 100%. pneumonic plague progression is biphasic, with an initial pre-inflammatory phase facilitating bacterial growth in the absence of host inflammation, followed by a pro-inflammatory phase marked by extensive neutrophil influx, an inflammatory cytokine storm, and severe tissue destruction. using a fret-based probe to quantitate injection of effector proteins by the y. pestis ...201324098126
yersinia pestis requires host rab1b for survival in macrophages.yersinia pestis is a facultative intracellular pathogen that causes the disease known as plague. during infection of macrophages y. pestis actively evades the normal phagosomal maturation pathway to establish a replicative niche within the cell. however, the mechanisms used by y. pestis to subvert killing by the macrophage are unknown. host rab gtpases are central mediators of vesicular trafficking and are commonly targeted by bacterial pathogens to alter phagosome maturation and killing by macr ...201526495854
circumventing y. pestis virulence by early recruitment of neutrophils to the lungs during pneumonic plague.pneumonic plague is a fatal disease caused by yersinia pestis that is associated with a delayed immune response in the lungs. because neutrophils are the first immune cells recruited to sites of infection, we investigated the mechanisms responsible for their delayed homing to the lung. during the first 24 hr after pulmonary infection with a fully virulent y. pestis strain, no significant changes were observed in the lungs in the levels of neutrophils infiltrate, expression of adhesion molecules, ...201525974210
yersinia infection tools-characterization of structure and function of adhesins.among the seventeen species of the gram-negative genus yersinia, three have been shown to be virulent and pathogenic to humans and animals-y. enterocolitica, y. pseudotuberculosis, and y. pestis. in order to be so, they are armoured with various factors that help them adhere to tissues and organelles, cross the cellular barrier and escape the immune system during host invasion. the group of proteins that mediate pathogen-host interactions constitute adhesins. invasin, ail, yada, yadb, yadc, pla, ...201223316485
yersinia pestis uses the ail outer membrane protein to recruit vitronectin.yersinia pestis, the agent of plague, requires the ail (attachment invasion locus) outer membrane protein to survive in the blood and tissues of its mammalian hosts. ail is important for both attachment to host cells and for resistance to complement-dependent bacteriolysis. previous studies have shown that ail interacts with components of the extracellular matrix, including fibronectin, laminin and heparan sulfate proteoglycans, and with the complement inhibitor c4b-binding protein. here, we dem ...201526377177
host langerin (cd207) is a receptor for yersinia pestis phagocytosis and promotes dissemination.yersinia pestis is a gram-negative bacterium that causes plague. after y. pestis overcomes the skin barrier, it encounters antigen-presenting cells (apcs), such as langerhans and dendritic cells. they transport the bacteria from the skin to the lymph nodes. however, the molecular mechanisms involved in bacterial transmission are unclear. langerhans cells (lcs) express langerin (cd207), a calcium-dependent (c-type) lectin. furthermore, y. pestis possesses exposed core oligosaccharides. in this st ...201525829141
nqrm (duf539) protein is required for maturation of bacterial na+-translocating nadh:quinone oxidoreductase.na(+)-translocating nadh:quinone oxidoreductase (na(+)-nqr) catalyzes electron transfer from nadh to ubiquinone in the bacterial respiratory chain, coupled with na(+) translocation across the membrane. na(+)-nqr maturation involves covalent attachment of flavin mononucleotide (fmn) residues, catalyzed by flavin transferase encoded by the nqr-associated apbe gene. analysis of complete bacterial genomes has revealed another putative gene (duf539, here renamed nqrm) that usually follows the apbe ge ...201626644436
production of outer membrane vesicles by the plague pathogen yersinia pestis.many gram-negative bacteria produce outer membrane vesicles (omvs) during cell growth and division, and some bacterial pathogens deliver virulence factors to the host via the release of omvs during infection. here we show that yersinia pestis, the causative agent of the disease plague, produces and releases native omvs under physiological conditions. these omvs, approximately 100 nm in diameter, contain multiple virulence-associated outer membrane proteins including the adhesin ail, the f1 outer ...201425198697
development of a taqman array card for acute-febrile-illness outbreak investigation and surveillance of emerging pathogens, including ebola virus.acute febrile illness (afi) is associated with substantial morbidity and mortality worldwide, yet an etiologic agent is often not identified. convalescent-phase serology is impractical, blood culture is slow, and many pathogens are fastidious or impossible to cultivate. we developed a real-time pcr-based taqman array card (tac) that can test six to eight samples within 2.5 h from sample to results and can simultaneously detect 26 afi-associated organisms, including 15 viruses (chikungunya, crime ...201526491176
structural characterisation of fabg from yersinia pestis, a key component of bacterial fatty acid synthesis.ketoacyl-acyl carrier protein reductases (fabg) are ubiquitously expressed enzymes that catalyse the reduction of acyl carrier protein (acp) linked thioesters within the bacterial type ii fatty acid synthesis (fasii) pathway. the products of these enzymes, saturated and unsaturated fatty acids, are essential components of the bacterial cell envelope. the fasii reductase enoyl-acp reductase (fabi) has been the focus of numerous drug discovery efforts, some of which have led to clinical trials, ye ...201526539719
structural characterisation of the beta-ketoacyl-acyl carrier protein synthases, fabf and fabh, of yersinia pestis.yersinia pestis, the causative agent of bubonic, pneumonic, and septicaemic plague, remains a major public health threat, with outbreaks of disease occurring in china, madagascar, and peru in the last five years. the existence of multidrug resistant y. pestis and the potential of this bacterium as a bioterrorism agent illustrates the need for new antimicrobials. the β-ketoacyl-acyl carrier protein synthases, fabb, fabf, and fabh, catalyse the elongation of fatty acids as part of the type ii fatt ...201526469877
role of yersinia pestis toxin complex family proteins in resistance to phagocytosis by polymorphonuclear leukocytes.yersinia pestis carries homologues of the toxin complex (tc) family proteins, which were first identified in other gram-negative bacteria as having potent insecticidal activity. the y. pestis tc proteins are neither toxic to fleas nor essential for survival of the bacterium in the flea, even though tc gene expression is highly upregulated and much more of the tc proteins yita and yipa are produced in the flea than when y. pestis is grown in vitro. we show that tc(+) and tc(-) y. pestis strains a ...201323959716
an alternative outer membrane secretion mechanism for an autotransporter protein lacking a c-terminal stable core.autotransporter (at) proteins are a broad class of virulence factors from gram-negative pathogens. at outer membrane (om) secretion appears simple in many regards, yet the mechanism that enables transport of the central at 'passenger' across the om remains unclear. om secretion efficiency for two at passengers is enhanced by approximately 20 kda stable core at the c-terminus of the passenger, but studies on a broader range of at proteins are needed in order to determine whether a stability diffe ...201324118465
early divergent strains of yersinia pestis in eurasia 5,000 years ago.the bacteria yersinia pestis is the etiological agent of plague and has caused human pandemics with millions of deaths in historic times. how and when it originated remains contentious. here, we report the oldest direct evidence of yersinia pestis identified by ancient dna in human teeth from asia and europe dating from 2,800 to 5,000 years ago. by sequencing the genomes, we find that these ancient plague strains are basal to all known yersinia pestis. we find the origins of the yersinia pestis ...201526496604
the pla gene, encoding plasminogen activator, is not specific to yersinia pestis.here we present evidence to show that the pla gene, previously thought to be specific to yersinia pestis, occurs in some strains of citrobacter koseri and escherichia coli. this means that detection of this gene on its own can no longer be taken as evidence of detection of y. pestis.201526438258
detection of a yersinia pestis gene homologue in rodent samples.a homologue to a widely used genetic marker, pla, for yersinia pestis has been identified in tissue samples of two species of rat (rattus rattus and rattus norvegicus) and of mice (mus musculus and apodemus sylvaticus) using a microarray based platform to screen for zoonotic pathogens of interest. samples were from urban locations in the uk (liverpool) and canada (vancouver). the results indicate the presence of an unknown bacterium that shares a homologue for the pla gene of yersinia pestis, so ...201627602258
genomic insights into a new citrobacter koseri strain revealed gene exchanges with the virulence-associated yersinia pestis ppcp1 plasmid.the history of infectious diseases raised the plague as one of the most devastating for human beings. far too often considered an ancient disease, the frequent resurgence of the plague has led to consider it as a reemerging disease in madagascar, algeria, libya, and congo. the genetic factors associated with the pathogenicity of yersinia pestis, the causative agent of the plague, involve the acquisition of the ppcp1 plasmid that promotes host invasion through the expression of the virulence fact ...201627014253
low-shear force associated with modeled microgravity and spaceflight does not similarly impact the virulence of notable bacterial pathogens.as their environments change, microbes experience various threats and stressors, and in the hypercompetitive microbial world, dynamism and the ability to rapidly respond to such changes allow microbes to outcompete their nutrient-seeking neighbors. viewed in that light, the very difference between microbial life and death depends on effective stress response mechanisms. in addition to the more commonly studied temperature, nutritional, and chemical stressors, research has begun to characterize m ...201425149449
structural basis for hypermodification of the wobble uridine in trna by bifunctional enzyme mnmc.methylaminomethyl modification of uridine or 2-thiouridine (mnm5u34 or mnm5s2u34) at the wobble position of trnas specific for glutamate, lysine and arginine are observed in escherichia coli and allow for specific recognition of codons ending in a or g. in the biosynthetic pathway responsible for this post-transcriptional modification, the bifunctional enzyme mnmc catalyzes the conversion of its hypermodified substrate carboxymethylaminomethyl uridine (cmnm5u34) to mnm5u34. mnmc catalyzes the fl ...201323617613
a lysr-type transcriptional regulator, rovm, senses nutritional cues suggesting that it is involved in metabolic adaptation of yersinia pestis to the flea gut.yersinia pestis has evolved as a clonal variant of yersinia pseudotuberculosis to cause flea-borne biofilm-mediated transmission of the bubonic plague. the lysr-type transcriptional regulator, rovm, is highly induced only during y. pestis infection of the flea host. rovm homologs in other pathogens regulate biofilm formation, nutrient sensing, and virulence; including in y. pseudotuberculosis, where rovm represses the major virulence factor, rova. here the role that rovm plays during flea infect ...201526348850
reciprocal regulation of yersinia pestis biofilm formation and virulence by rovm and rova.rova is known to enhance yersinia pestis virulence by directly upregulating the psa loci. this work presents a complex gene regulatory paradigm involving the reciprocal regulatory action of rovm and rova on the expression of biofilm and virulence genes as well as on their own genes. rovm and rova enhance and inhibit y. pestis biofilm production, respectively, whereas rovm represses virulence in mice. rovm directly stimulates the transcription of hmst, hmscde and rovm, while indirectly enhancing ...201626984293
flea-associated bacterial communities across an environmental transect in a plague-endemic region of uganda.the vast majority of human plague cases currently occur in sub-saharan africa. the primary route of transmission of yersinia pestis, the causative agent of plague, is via flea bites. non-pathogenic flea-associated bacteria may interact with y. pestis within fleas and it is important to understand what factors govern flea-associated bacterial assemblages. six species of fleas were collected from nine rodent species from ten ugandan villages between october 2010 and march 2011. a total of 660,345 ...201526485147
structural basis for the specific recognition of dual receptors by the homopolymeric ph 6 antigen (psa) fimbriae of yersinia pestis.the ph 6 antigen (psa) of yersinia pestis consists of fimbriae that bind to two receptors: β1-linked galactosyl residues in glycosphingolipids and the phosphocholine group in phospholipids. despite the ubiquitous presence of either moiety on the surface of many mammalian cells, y. pestis appears to prefer interacting with certain types of human cells, such as macrophages and alveolar epithelial cells of the lung. the molecular mechanism of this apparent selectivity is not clear. site-directed mu ...201223277582
outer membrane proteins ail and ompf of yersinia pestis are involved in the adsorption of t7-related bacteriophage yep-phi.yep-phi is a t7-related bacteriophage specific to yersinia pestis, and it is routinely used in the identification of y. pestis in china. yep-phi infects y. pestis grown at both 20°c and 37°c. it is inactive in other yersinia species irrespective of the growth temperature. based on phage adsorption, phage plaque formation, affinity chromatography, and western blot assays, the outer membrane proteins of y. pestis ail and ompf were identified to be involved, in addition to the rough lipopolysacchar ...201324006436
navigable rivers facilitated the spread and recurrence of plague in pre-industrial europe.infectious diseases have become a rising challenge to mankind in a globalizing world. yet, little is known about the inland transmission of infectious diseases in history. in this study, we based on the spatio-temporal information of 5559 plague (yersinia pestis) outbreaks in europe and its neighboring regions in ad1347-1760 to statistically examine the connection between navigable rivers and plague outbreak. our results showed that 95.5% of plague happened within 10 km proximity of navigable ri ...201627721393
'candidatus rickettsia asemboensis' and wolbachia spp. in ctenocephalides felis and pulex irritans fleas removed from dogs in ecuador.flea-borne infections are distributed worldwide. up to date there are no reports about microorganisms associated to fleas in ecuador.201425266919
blood meal identification in off-host cat fleas (ctenocephalides felis) from a plague-endemic region of uganda.the cat flea, ctenocephalides felis, is an inefficient vector of the plague bacterium (yersinia pestis) and is the predominant off-host flea species in human habitations in the west nile region, an established plague focus in northwest uganda. to determine if c. felis might serve as a y. pestis bridging vector in the west nile region, we collected on- and off-host fleas from human habitations and used a real-time polymerase chain reaction-based assay to estimate the proportion of off-host c. fel ...201223208882
the fleas (siphonaptera) in iran: diversity, host range, and medical importance.flea-borne diseases have a wide distribution in the world. studies on the identity, abundance, distribution and seasonality of the potential vectors of pathogenic agents (e.g. yersinia pestis, francisella tularensis, and rickettsia felis) are necessary tools for controlling and preventing such diseases outbreaks. the improvements of diagnostic tools are partly responsible for an easier detection of otherwise unnoticed agents in the ectoparasitic fauna and as such a good taxonomical knowledge of ...201728068343
combining real-time polymerase chain reaction using sybr green i detection and sequencing to identify vertebrate bloodmeals in fleas.programs that aim to control vector-borne zoonotic diseases require information on zoonotic hosts and on the feeding behavior of bridging vectors that are capable of transmitting pathogens from those hosts to humans. here we describe an assay developed to identify bloodmeals in field-collected cat fleas (ctenocephalides felis bouché) to assess this species' potential role as a yersinia pestis bridging vector in a plague-endemic region of uganda. our assay uses a single primer set and sybr green ...023270174
genomic comparison of escherichia coli o104:h4 isolates from 2009 and 2011 reveals plasmid, and prophage heterogeneity, including shiga toxin encoding phage stx2.in may of 2011, an enteroaggregative escherichia coli o104:h4 strain that had acquired a shiga toxin 2-converting phage caused a large outbreak of bloody diarrhea in europe which was notable for its high prevalence of hemolytic uremic syndrome cases. several studies have described the genomic inventory and phylogenies of strains associated with the outbreak and a collection of historical e. coli o104:h4 isolates using draft genome assemblies. we present the complete, closed genome sequences of a ...201223133618
synthesis, characterization, and antimicrobial activity of silver carbene complexes derived from 4,5,6,7-tetrachlorobenzimidazole against antibiotic resistant bacteria.silver n-heterocyclic carbene complexes have been shown to have great potential as antimicrobial agents, affecting a wide spectrum of both gram-positive and gram-negative bacteria. a new series of three silver carbene complexes (sccs) based on 4,5,6,7-tetrachlorobenzimidazole has been synthesized, characterized, and tested against a panel of clinical strains of bacteria. the imidazolium salts and their precursors were characterized by elemental analysis, mass spectrometry, (1)h and (13)c nmr spe ...201222402409
isecp1-mediated transposition of blakpc into the chromosome of a clinical isolate of acinetobacter baumannii from puerto rico.carbapenems are the last-resort antibiotics for the treatment of infections caused by multidrug-resistant gram-negative bacilli. klebsiella pneumoniae carbapenemase (kpc) hydrolyses β-lactam antibiotics including the carbapenems. kpcs have been detected in enterobacteriaceae and pseudomonas aeruginosa isolates worldwide associated with transposon tn4401 commonly located in plasmids. acinetobacter baumannii has become an important multidrug-resistant nosocomial pathogen capable of hydrolysing the ...201425246647
human louse-transmitted infectious diseases.several of the infectious diseases associated with human lice are life-threatening, including epidemic typhus, relapsing fever, and trench fever, which are caused by rickettsia prowazekii, borrelia recurrentis, and bartonella quintana, respectively. although these diseases have been known for several centuries, they remain a major public health concern in populations living in poor-hygiene conditions because of war, social disruption, severe poverty, or gaps in public health management. poor-hyg ...201222360386
inhibition of pseudomonas aeruginosa exsa dna-binding activity by n-hydroxybenzimidazoles.the pseudomonas aeruginosa type iii secretion system (t3ss) is a primary virulence determinant and a potential target for antivirulence drugs. one candidate target is exsa, a member of the arac family of dna-binding proteins required for expression of the t3ss. a previous study identified small molecules based on an n-hydroxybenzimidazole scaffold that inhibit the dna-binding activity of several arac proteins, including exsa. in this study, we further characterized a panel of n-hydroxybenzimidaz ...201626574012
exsa and lcrf recognize similar consensus binding sites, but differences in their oligomeric state influence interactions with promoter dna.exsa activates type iii secretion system (t3ss) gene expression in pseudomonas aeruginosa and is a member of the arac family of transcriptional regulators. arac proteins contain two helix-turn-helix (hth) dna binding motifs. one helix from each hth motif inserts into the major groove of the dna to make base-specific contacts with the promoter region. the amino acids that comprise the hth motifs of exsa are nearly identical to those in lcrf/virf, the activators of t3ss gene expression in the path ...201324142246
thiamine triphosphatase and the cyth superfamily of proteins.the cyth superfamily of proteins was named after its two founding members, the cyab adenylyl cyclase from aeromonas hydrophila, and the human 25-kda thiamine triphosphatase (thtpase). members of this superfamily of proteins exist in all organisms, including bacteria, archaeons, fungi, plants, and animals (except birds), and can be traced back to the last universal common ancestor. their sequences include several charged residues involved in divalent cation and triphosphate binding. indeed, all m ...201324021036
staphylococcus epidermidis biofilms: functional molecules, relation to virulence, and vaccine potential.medical device-associated infections, most frequently caused by staphylococcus epidermidis and staphylococcus aureus, are of increasing importance in modern medicine. the formation of adherent, multilayered bacterial biofilms is crucial in the pathogenesis of these infections. polysaccharide intercellular adhesin (pia), a homoglycan of β-1,6-linked 2-acetamido-2-deoxy-d: -glucopyranosyl residues, of which about 15% are non-n-acetylated, is central to biofilm accumulation in staphylococci. it tra ...200922328030
demographic characteristics and infectious diseases of a population of american black bears in humboldt county, california.american black bears (ursus americanus) are common, widely distributed, and broad-ranging omnivorous mammals in northern california forests. bears may be susceptible to pathogens infecting both domestic animals and humans. monitoring bear populations, particularly in changing ecosystems, is important to understanding ecological features that could affect bear population health and influence the likelihood that bears may cause adverse impacts on humans. in all, 321 bears were captured between may ...201525700042
the composition and transmission of microbiome in hard tick, ixodes persulcatus, during blood meal.the tick ixodes persulcatus is the predominant tick species in northeastern china, and it is a major vector in transmission of tick-borne diseases. by 16s rrna illumina sequencing, we investigated the microbiome of i. persulcatus and assessed the variation of the microbiome before and after blood feeding. the prolonged blood meal dramatically altered the composition of the microbiome but did not influence the bacterial diversity. overall, 373 and 289 bacterial genera were assigned to unfed and f ...201425150725
zoonotic vector-borne bacterial pathogens in california mountain lions (puma concolor), 1987-2010.sera collected from 442 mountain lions in 48 california counties between the years of 1987 and 2010 were tested using immunofluorescence assays and agglutination tests for the presence of antibodies reactive to yersinia pestis, francisella tularensis, bartonella henselae, borrelia burgdorferi, and anaplasma phagocytophilum antigens. data were analyzed for spatial and temporal trends in seropositivity. seroprevalences for b. burgdorferi (19.9%) and b. henselae (37.1%) were relatively high, with t ...201222925024
in vitro and in vivo activity of omadacycline against two biothreat pathogens: bacillus anthracis and yersinia pestis.introduction: the in vitro activity and in vivo efficacy of omadacycline (omc) were evaluated against the causative pathogens of anthrax and plague, bacillus anthracis and yersinia pestis, respectively.methods: minimum inhibitory concentrations (mics) of omc were determined by microbroth dilution according to clsi guidelines for 30 isolates each of y. pestis and b. anthracis the in vivo efficacy of omadacycline was studied at a range of dosages in both a post exposure prophylaxis (pep) murine mo ...201728223382
characterization of yersinia species by protein profiling using automated microfluidic capillary electrophoresis.yersinia pestis is a biological agent of high risk to national security due to its ability to be easily disseminated and transmitted among humans. if y. pestis was to be utilized in a deliberate disease outbreak it would be essential to rapidly and accurately identify the agent. current identification methods for yersinia species are limited by their reliance on cultivation, the time taken to achieve results and/or the use of protocols that are not amenable for field use. faster identification m ...201728019002
a self-quenching-resistant carbon nanodot powder with multicolored solid-state fluorescence for ultra-fast staining of various representative bacterial species within one minute.in this study, we prepared self-quenching-resistant solid-state fluorescent carbon nanodots (sfcds) without any other solid matrices. the sfcds were prepared using a one-step microwave synthesis method through precise control of the heating power and time. the resulting sfcd powder showed excitation-dependent emission behavior with a maximum fluorescence quantum yield of 40%. the multicolored sfcds were successfully used as fluorescent agents for rapid staining of 14 representative bacterial spe ...201627874136
avoiding pandemic fears in the subway and conquering the platypus.metagenomics is increasingly used not just to show patterns of microbial diversity but also as a culture-independent method to detect individual organisms of intense clinical, epidemiological, conservation, forensic, or regulatory interest. a widely reported metagenomic study of the new york subway suggested that the pathogens yersinia pestis and bacillus anthracis were part of the "normal subway microbiome." in their article in msystems, hsu and collaborators (msystems 1(3):e00018-16, 2016, htt ...201727832215
cationic host defense peptides; novel antimicrobial therapeutics against category a pathogens and emerging infections.cationic host defense peptides (hdp, also known as antimicrobial peptides) are crucial components of the innate immune system and possess broad-spectrum antibacterial, antiviral, and immunomodulatory activities. they can contribute to the rapid clearance of biological agents through direct killing of the organisms, inhibition of pro-inflammatory mediators such as lipopolysaccharide, and by modulating the inflammatory response to infection. category a biological agents and materials, as classifie ...201727315342
fast, sensitive point of care electrochemical molecular system for point mutation and select agent detection.point of care molecular diagnostics benefits from a portable battery-operated device capable of performing a fast turnaround using reliable inexpensive cartridges. we describe a prototype device for performing a molecular diagnostics test for clinical and biodefense samples in 16 minutes using a prototype capable of an 8 minute pcr reaction, followed by hybridization and detection on an electrochemical microarray based on the i-stat® system. we used human buccal swabs for hemochromatosis testing ...201627280174
an internal standard approach for homogeneous tr-fret immunoassays facilitates the detection of bacteria, biomarkers, and toxins in complex matrices.the recent development of a homogeneous time-resolved förster resonance energy transfer (tr-fret) immunoassay enables one-step, rapid (minutes), and direct detection compared to the multistep, time-consuming (hours), heterogeneous elisa-type immunoassays. the use of the time-resolved effect of a donor lanthanide complex with a delay time of microseconds and large stokes shift enables the separation of positive signals from the background autofluorescence of the sample. however, this study shows ...201627236318
rapid antimicrobial susceptibility testing of bacillus anthracis, yersinia pestis, and burkholderia pseudomallei by use of laser light scattering technology.rapid methods to determine antimicrobial susceptibility would assist in the timely distribution of effective treatment or postexposure prophylaxis in the aftermath of the release of bacterial biothreat agents such as bacillus anthracis, yersinia pestis, or burkholderia pseudomallei conventional susceptibility tests require 16 to 48 h of incubation, depending on the bacterial species. we evaluated a method that is based on laser light scattering technology that measures cell density in real time. ...201626984973
[optimization of labeling and localizing bacterial membrane and nucleus with fm4-64 and hoechst dyes].to observe cell membrane and nucleus in bacteria for subcellular localization.201526665605
engineered nanoconstructs for the multiplexed and sensitive detection of high-risk pathogens.many countries categorize the causative agents of severe infectious diseases as high-risk pathogens. given their extreme infectivity and potential to be used as biological weapons, a rapid and sensitive method for detection of high-risk pathogens (e.g., bacillus anthracis, francisella tularensis, yersinia pestis, and vaccinia virus) is highly desirable. here, we report the construction of a novel detection platform comprising two units: (1) magnetic beads separately conjugated with multiple capt ...201626462853
application of pyrosequencing® in food biodefense.the perpetration of a bioterrorism attack poses a significant risk for public health with potential socioeconomic consequences. it is imperative that we possess reliable assays for the rapid and accurate identification of biothreat agents to make rapid risk-informed decisions on emergency response. the development of advanced methodologies for the detection of biothreat agents has been evolving rapidly since the release of the anthrax spores in the mail in 2001, and recent advances in detection ...201526103911
curing both virulent mega-plasmids from bacillus anthracis wild-type strain a16 simultaneously using plasmid incompatibility.plasmid-cured derivative strains of bacillus anthracis are frequently used in laboratory studies. plasmid incompatibility, which does not increase the risk of chromosomal mutation, is a useful method for plasmid curing. however, in bacteria containing multiple plasmids, it often requires the sequential introduction of multiple, specific incompatibility plasmids. this lengthy process renders the traditional plasmid incompatibility method inefficient and mutation-prone. in this study, we successfu ...201526059513
monitoring biothreat agents (francisella tularensis, bacillus anthracis and yersinia pestis) with a portable real-time pcr instrument.in the event of suspected releases or natural outbreaks of contagious pathogens, rapid identification of the infectious agent is essential for appropriate medical intervention and disease containment. the purpose of this study was to compare the performance of a novel portable real-time pcr thermocycler, pikoreal™, to the standard real-time pcr thermocycler, applied biosystems® 7300 (abi 7300), for the detection of three high-risk biothreat bacterial pathogens: francisella tularensis, bacillus a ...201526043838
[development and comparative evaluation of up-converting phosphor technology based lateral flow assay for rapid detection of yersinia pestis, bacillus anthracis spore and brucella spp].to develop an up-converting phosphor technology based lateral flow (upt-lf) assay for rapid and quantitative detection of yersinia pestis, bacillus anthracis spore and brucella spp.and make the comparison with biothreat alert (bta) test strips (tetracore inc., usa).201525876487
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