Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| synthesis and biological evaluation of novel 1,3,5-triazine derivatives as antimicrobial agents. | numerous studies have contributed to the development of natural and synthetic antimicrobial peptides as a prospective source of antibiotic agents. based on the concept that cationic charge, bulk, and lipophilicity are major factors determining antibacterial activity in these peptides, we designed and screened several combinatorial libraries based on 1,3,5-triazine as a template. a set of compounds were identified to show potent antimicrobial activity together with low hemolytic activity. | 2008 | 18226902 |
| analysis of a novel spore antigen in bacillus anthracis that contributes to spore opsonization. | the significance of bacillus anthracis as an agent of bioterrorism has been well established. an understanding of both the pathogenesis and the host response is required to elucidate approaches to more rapidly detect and effectively prevent or treat anthrax. current vaccine strategies are focused primarily on production of antibodies against the protective antigen components of the anthrax toxins, which are secreted by the bacilli. a better understanding of the dynamic morphology of the dormant ... | 2008 | 18227265 |
| colloidal gold-polystyrene bead hybrid for chemiluminescent detection of sequence-specific dna. | a sensitive chemiluminescent (cl) detection of sequence-specific dna has been developed by taking advantage of a magnetic separation/mixing process and the amplification feature of colloidal gold labels. in this protocol, the target oligonucleotides are hybridized with magnetic bead-linked capture probes, followed by the hybridization of the biotin-terminated amplifying dna probes and the binding of streptavidin-coated gold nanoparticles; the nanometer-sized gold tags are then dissolved and quan ... | 2008 | 18227945 |
| development of an automated dna purification module using a micro-fabricated pillar chip. | we present a fully automated dna purification module comprised of a micro-fabricated chip and sequential injection analysis system that is designed for use within autonomous instruments that continuously monitor the environment for the presence of biological threat agents. the chip has an elliptical flow channel containing a bed (3.5 x 3.5 mm) of silica-coated pillars with height, width and center-to-center spacing of 200, 15, and 30 microm, respectively, which provides a relatively large surfac ... | 2008 | 18227949 |
| [the relationship between the conditions of cultivation and sporification of various bacillus strains and the results of the evaluation of the sporocidal activity of chemical desinfectants]. | the researchers compared the main microbiological characteristics of some bacillus antracoides strains after their cultivation in different nutrient media. the study found that the growth and sporification rate, r-s dissociation ability, and sensitivity to disinfectants are strain properties and significantly depend on the composition of the nutrient medium. | 2007 | 18228663 |
| functional peg-modified thin films for biological detection. | we report a general procedure to prepare functional organic thin films for biological assays on oxide surfaces. silica surfaces were functionalized by self-assembly of an amine-terminated silane film using both vapor- and solution-phase deposition of 3'-aminopropylmethyldiethoxysilane (apmdes). we found that vapor-phase deposition of apmdes under reduced pressure produced the highest quality monolayer films with uniform surface coverage, as determined by atomic force microscopy (afm), ellipsomet ... | 2008 | 18229965 |
| fieldable genotyping of bacillus anthracis and yersinia pestis based on 25-loci multi locus vntr analysis. | anthrax and plague are diseases caused by bacillus anthracis and yersinia pestis respectively. these bacteria are etiological agents for worldwide zoonotic diseases and are considered among the most feared potential bioterror agents. strain differentiation is difficult for these microorganisms because of their high intraspecies genome homogeneity. moreover, fast strain identification and comparison with known genotypes may be crucial for naturally occurring outbreaks versus bioterrorist events d ... | 2008 | 18230125 |
| waterborne pathogen detection using raman spectroscopy. | raman spectroscopy is being evaluated as a candidate technology for waterborne pathogen detection. we have investigated the impact of key experimental and background interference parameters on the bacterial species level identification performance of raman detection. these parameters include laser-induced photodamage threshold, composition of water matrix, and organism aging in water. the laser-induced photodamage may be minimized by operating a 532 nm continuous wave laser excitation at laser p ... | 2008 | 18230198 |
| synthesis of a hexasaccharide repeating unit from bacillus anthracis vegetative cell walls. | the first synthesis of hexasaccharide 1 representing a repeat unit of a polysaccharide specific to the vegetative cell wall of bacillus anthracis is reported. the synthetic hexasaccharide is equipped with an n-pentenyl handle at the reducing terminus to allow for further functionalization. key transformations during the synthesis are the conversion of a glucose into a mannosazide residue, a (2+2) coupling, followed by double alpha-galactosylation to furnish the hexasaccharide, and global deprote ... | 2008 | 18232704 |
| influence of nisin on the resistance of bacillus anthracis sterne spores to heat and hydrostatic pressure. | the influence of nisin on the heat and pressure resistance of bacillus anthracis sterne spores was examined. the decimal reduction times (d-value) of spores in milk (2% fat) at 80, 85, and 90 degrees c were determined. in the absence of nisin, the d-values were 30.09, 9.30, and 3.86 min, respectively. the d-values of spores heated in the presence of nisin (1 mg/ml) were not significantly different (p = 0.05). however, spores heated in the presence of nisin had a 1- to 2-log reduction in viabilit ... | 2008 | 18236684 |
| a high resolution four-locus multiplex single nucleotide repeat (snr) genotyping system in bacillus anthracis. | the allelic identities of single nucleotide repeat (snr) markers in bacillus anthracis are typically ascertained by dna sequencing through the direct repeat. here we describe a reproducible method for genotyping closely related isolates by using four snr loci in a multiplex-pcr capillary electrophoresis system amenable to high-throughput analysis. | 2008 | 18237793 |
| structure and specificity of lamprey monoclonal antibodies. | adaptive immunity in jawless vertebrates (lamprey and hagfish) is mediated by lymphocytes that undergo combinatorial assembly of leucine-rich repeat (lrr) gene segments to create a diverse repertoire of variable lymphocyte receptor (vlr) genes. immunization with particulate antigens induces vlr-b-bearing lymphocytes to secrete antigen-specific vlr-b antibodies. here, we describe the production of recombinant vlr-b antibodies specific for bcla, a major coat protein of bacillus anthracis spores. t ... | 2008 | 18238899 |
| deletion of dnan1 generates a mutator phenotype in bacillus anthracis. | the dnan gene in eubacteria is an essential gene that encodes the beta subunit of replicative dna polymerase. nearly all eubacterial genomes sequenced to date predict a single copy of the dnan gene in a well-conserved neighboring gene context. however, 19 genomes out of 348 scanned, including bacillus anthracis, bacillus cereus, bacillus thuringiensis, and bacillus weihenstephanensis, predict more than one dnan gene. in most cases, these genomes appear to maintain a copy of the dnan homolog in i ... | 2008 | 18242150 |
| performance evaluation of five commercial real-time pcr reagent systems using taqman assays for b. anthracis detection. | real-time pcr assay sensitivity is affected by the choice and concentrations of reaction mix constituents among other factors such as primers, probes, and analytical assay platforms. commercially available reagent mixes facilitate pcr assay set-up with fewer steps and timeliness. however, determination of analytical assay framework is important for ready-to-use real-time pcr reagent systems for rapid, quantitative and accurate detection of bioterror pathogens such as bacillus anthracis. | 2008 | 18242168 |
| binding of n-terminal fragments of anthrax edema factor (ef(n)) and lethal factor (lf(n)) to the protective antigen pore. | anthrax toxin consists of three different molecules: the binding component protective antigen (pa, 83 kda), and the enzymatic components lethal factor (lf, 90 kda) and edema factor (ef, 89 kda). the 63 kda c-terminal part of pa, pa(63), forms heptameric channels that insert in endosomal membranes at low ph, necessary to translocate ef and lf into the cytosol of target cells. in many studies, about 30 kda n-terminal fragments of the enzymatic components ef (254 amino acids) and lf (268 amino acid ... | 2008 | 18243126 |
| anthrose biosynthetic operon of bacillus anthracis. | the exosporium of bacillus anthracis spores consists of a basal layer and an external hair-like nap. the nap is composed primarily of the glycoprotein bcla, which contains a collagen-like region with multiple copies of a pentasaccharide side chain. this oligosaccharide possesses an unusual terminal sugar called anthrose, followed by three rhamnose residues and a protein-bound n-acetylgalactosamine. based on the structure of anthrose, we proposed an enzymatic pathway for its biosynthesis. examina ... | 2008 | 18245286 |
| potent inhibition of tumor angiogenesis by the matrix metalloproteinase-activated anthrax lethal toxin: implications for broad anti-tumor efficacy. | angiogenesis is a critical step in solid tumor progression. the mitogen-activated protein kinase (mapk) signaling pathways are central to this process, and thus present attractive targets for angiogenesis inhibition. anthrax lethal toxin (letx), secreted from the gram positive bacillus anthracis, demonstrates potent mapk pathway inhibition. in vivo efficacy studies revealed that letx has broad anti-tumor efficacy via the targeting of angiogenesis. however, specificity in animal models was limite ... | 2008 | 18245947 |
| antibody responses of variable lymphocyte receptors in the lamprey. | lamprey and hagfish, the living representatives of jawless vertebrates, use genomic leucine-rich-repeat cassettes for the combinatorial assembly of diverse antigen receptor genes encoding variable lymphocyte receptors of two types: vlra and vlrb. we describe here the vlrb-bearing lineage of lymphocytes in sea lamprey. these cells responded to repetitive carbohydrate or protein determinants on bacteria or mammalian cells with lymphoblastoid transformation, proliferation and differentiation into p ... | 2008 | 18246071 |
| analysis of epitope information related to bacillus anthracis and clostridium botulinum. | we have reviewed the information about epitopes of immunological interest from clostridium botulinum and bacillus anthracis, by mining the immune epitope database and analysis resource. for both pathogens, the vast majority of epitopes reported to date are derived from a single protein: the protective antigen of b. anthracis and the neurotoxin type a of c. botulinum. a detailed analysis of the data was performed to characterize the function, localization and conservancy of epitopes identified as ... | 2008 | 18251694 |
| detoxified lethal toxin as a potential mucosal vaccine against anthrax. | the nontoxic mutant lethal factor (mlf; which has the e687c substitution) and functional protective antigen (pa63) of bacillus anthracis were evaluated for their use as mucosal vaccines against anthrax in a/j mice. intranasal vaccination of three doses of 30 microg of mlf or 60 microg of pa63 elicited significant serum and mucosal antibody responses, with anthrax lethal toxin-neutralizing titers of 40 and 60 in immune sera, respectively. however, only 30% and 60% of the vaccinated animals in the ... | 2008 | 18256208 |
| synthesis and biological evaluation of inhibitors of thymidine monophosphate kinase from bacillus anthracis. | nineteen lipophilic thymidine phosphate-mimicking compounds were designed and synthesized as potential inhibitors of thymidine monophosphate kinase of bacillus anthracis, a gram-positive bacterium that causes anthrax. these thymidine analogues were substituted at the 5'-postion with sulfonamide-, amide-, (thio)urea-, or triazole groups, which served as lipophilic surrogates for phosphate. three of the tested compounds produced inhibition of b. anthracis sterne growth and/or thymidine monophospha ... | 2008 | 18260009 |
| expression and characterization of aiia gene from bacillus subtilis bs-1. | ahl-lactonase (aiia), a metallo-beta-lactamase produced by bacillus thuringiensis, bacillus cereus and bacillus anthracis, specifically hydrolyzes n-acyl-homoserine lactones (ahls) secreted by gram-negative bacteria and thereby attenuates the symptoms caused by plant pathogens. in this study, an aiia gene was cloned from bacillus subtilis bs-1 by pcr with a pair of degenerate primers. the deduced 250 amino acid sequence contained two small conserved regions, 103shlhfdh109 and 166tpghtpgh173, whi ... | 2008 | 18261893 |
| degradation of circulating von willebrand factor and its regulator adamts13 implicates secreted bacillus anthracis metalloproteases in anthrax consumptive coagulopathy. | pathology data from the anthrax animal models show evidence of significant increases in vascular permeability coincident with hemostatic imbalances manifested by thrombocytopenia, transient leucopenia, and aggressive disseminated intravascular coagulation. in this study we hypothesized that anthrax infection modulates the activity of von willebrand factor (vwf) and its endogenous regulator adamts13, which play important roles in hemostasis and thrombosis, including interaction of endothelial cel ... | 2008 | 18263586 |
| killing of macrophages by anthrax lethal toxin: involvement of the n-end rule pathway. | macrophages from certain inbred mouse strains are rapidly killed (< 90 min) by anthrax lethal toxin (lt). lt cleaves cytoplasmic mek proteins at 20 min and induces caspase-1 activation in sensitive macrophages at 50-60 min, but the mechanism of lt-induced death is unknown. proteasome inhibitors block lt-mediated caspase-1 activation and can protect against cell death, indicating that the degradation of at least one cellular protein is required for lt-mediated cell death. proteins can be degraded ... | 2008 | 18266992 |
| anthrax lethal toxin induces cell death-independent permeability in zebrafish vasculature. | vascular dysfunction has been reported in human cases of anthrax, in mammalian models of bacillus anthracis, and in animals injected with anthrax toxin proteins. to examine anthrax lethal toxin effects on intact blood vessels, we developed a zebrafish model that permits in vivo imaging and evaluation of vasculature and cardiovascular function. vascular defects monitored in hundreds of embryos enabled us to define four stages of phenotypic progression leading to circulatory dysfunction. we demons ... | 2008 | 18268319 |
| the effects of anthrax lethal factor on the macrophage proteome: potential activity on nitric oxide synthases. | anthrax lethal factor (letx) is a critical virulence factor in toxin-challenged cells, as lethal factor (lf) cleaves mitogen-activated protein kinase kinases (mkks), inhibiting their activity. the physiological importance of this cleavage for macrophage cytolysis remains unclear, because similar proteolysis has been also observed in letx-resistant macrophages. here, we analyzed in vitro proteomic profiles of raw264.7 lysates treated with lf. in our experiments, neuronal no synthase (nnos) was fo ... | 2008 | 18269913 |
| self-transfer and mobilisation capabilities of the pxo2-like plasmid pbt9727 from bacillus thuringiensis subsp. konkukian 97-27. | recent characterisations of plasmids related to the anthrax virulence plasmids pxo1 and pxo2 in clinical isolates of bacillus cereus and bacillus thuringiensis have contributed to the emerging picture of a virulence-associated plasmid pool in the b. cereus sensu lato group. the family of pxo2-like plasmids includes the conjugative plasmid paw63 from the biopesticide strain b. thuringiensis subsp. kurstaki hd73 and the heretofore cryptic plasmid pbt9727 from the clinical strain b. thuringiensis s ... | 2008 | 18272219 |
| efficient production and characterization of bacillus anthracis lethal factor and a novel inactive mutant rlfm-y236f. | lethal factor (lf) is a 90kda zinc metalloprotease that plays an important role in the virulence of anthrax. recombinant lf (rlf) is an effective tool to study anthrax pathogenesis and treatment. in this study, the lf gene was cloned into the escherichia coli expression vector pgex-6p-1 and expressed as a gst fusion protein (gst-rlf) in e. coli bl21-codonplus (de3)-ril cells with 0.2mm iptg induction at 28 degrees c. the gst-rlf protein was purified and the gst-tag was then cleaved in a single s ... | 2008 | 18276157 |
| renewable enzyme reactors based on beds of artificial gel antibodies. | a novel approach is described for the synthesis of beds for enzyme reactors. the method is based on the use of artificial antibodies in the form of polyacrylamide gel particles with diameters around 0.1-0.3 mm. these gel particles mimic protein antibodies, raised in experimental animals, in the sense that they selectively recognize and adsorb only the protein present during the preparation of the "antibodies". the gel antibodies have several advantages over conventional protein antibodies, which ... | 2008 | 18280576 |
| n-substituted 3-acetyltetramic acid derivatives as antibacterial agents. | in order to expand the structure-activity relationship of tetramic acid molecules with structural similarity to the antibiotic reutericyclin, 22 compounds were synthesized and tested against a panel of clinically relevant bacteria. key structural changes on the tetramic acid core affected antibacterial activity. various compounds in the n-alkyl 3-acetyltetramic acid series exhibited good activity against gram-positive bacterial pathogens including bacillus anthracis, propionibacterium acnes, ent ... | 2008 | 18281930 |
| nucleotide biosynthesis is critical for growth of bacteria in human blood. | proliferation of bacterial pathogens in blood represents one of the most dangerous stages of infection. growth in blood serum depends on the ability of a pathogen to adjust metabolism to match the availability of nutrients. although certain nutrients are scarce in blood and need to be de novo synthesized by proliferating bacteria, it is unclear which metabolic pathways are critical for bacterial growth in blood. in this study, we identified metabolic functions that are essential specifically for ... | 2008 | 18282099 |
| performance of an algorithm for assessing smallpox risk among patients with rashes that may be confused with smallpox. | after the 2001 anthrax bioterror attacks, the centers for disease control and prevention developed an algorithm to evaluate patients rapidly for suspected smallpox. a prospective, multicenter study examined the performance of this algorithm in assessing patients with an acute, generalized vesicular or pustular rash (agvpr) admitted to emergency departments and inpatient units of 12 acute-care hospitals in 6 states. of 26,747 patients (3.5% of all admissions) with rashlike conditions screened, 89 ... | 2008 | 18284359 |
| enhancement of antibody responses to bacillus anthracis protective antigen domain iv by use of calreticulin as a chimeric molecular adjuvant. | the generation of protective humoral immune responses against the receptor-binding domain (domain iv) of protective antigen [pa(div)] of bacillus anthracis represents a plausible approach against anthrax toxin. in the current study, we have developed a naked dna vaccine encoding calreticulin (crt) linked to pa(div) of bacillus anthracis [crt/pa(div)]. we transfected a human embryonic kidney cell line (hek 293) with crt/pa(div) dna and performed western blotting and confocal microscopy analysis. ... | 2008 | 18285494 |
| glycosyltransferase: a specific marker for the discrimination of bacillus anthracis from the bacillus cereus group. | bacillus anthracis, the aetiological agent of anthrax, has been taxonomically classified with the bacillus cereus group, which comprises b. cereus, bacillus thuringiensis, bacillus mycoides, bacillus pseudomycoides and bacillus weihenstephanensis. although the pathogenesis and ecological manifestations may be different, b. anthracis shares a high degree of dna sequence similarity with its group member species. as a result, the discrimination of b. anthracis from its close relatives in the b. cer ... | 2008 | 18287289 |
| binary actin-adp-ribosylating toxins and their use as molecular trojan horses for drug delivery into eukaryotic cells. | binary bacterial toxins are unique ab-type toxins, composed of two non-linked proteins that act as a binding/translocation component and an enzyme component. all known actin-adp-ribosylating toxins from clostridia possess this binary structure. this toxin family is comprised of the prototypical clostridium botulinum c2 toxin, clostridium perfringens iota toxin, clostridium difficile cdt, and clostridium spiroforme toxin. once in the cytosol of host cells, these toxins transfer an adp-ribose moie ... | 2008 | 18289001 |
| discovery and development of anthrax lethal factor metalloproteinase inhibitors. | anthrax is caused by infection with bacillus anthracis, a spore forming, rod-shaped, encapsulated gram positive bacteria. the disease manifests itself in distinct ways depending on the route of entry of infective bacterial spores: cutaneous, inhalational, and gastrointestinal. though rare in humans, inhalational anthrax has become a major concern due to the capacity for spores to be weaponized. the limited success of antibiotic therapy has motivated investigation of complementary therapeutic str ... | 2008 | 18289054 |
| anthrax in animals and humans in mongolia. | anthrax is endemic throughout mongolia, except in the semi-desert and desert areas of the south. the prevalence of anthrax in mongolia had drastically decreased since the 1950s due to the use of anthrax antiserum and vaccines, but the privatisation of the animal husbandry sector and changes in the structures of the veterinary and medical delivery systems in mongolia over the last decade have resulted in challenges for disease control. animal and human anthrax has become an increasing problem sin ... | 2007 | 18293618 |
| wet and dry density of bacillus anthracis and other bacillus species. | to determine the wet and dry density of spores of bacillus anthracis and compare these values with the densities of other bacillus species grown and sporulated under similar conditions. | 2008 | 18298528 |
| standardized, mathematical model-based and validated in vitro analysis of anthrax lethal toxin neutralization. | quantification of anthrax lethal toxin (ltx) neutralization activity (tna) is pivotal in assessing protective antibody responses to anthrax vaccines and for evaluation of immunotherapies for anthrax. we have adapted and redesigned the tna assay to establish a unifying, standardized, quantitative and validated technology platform for ltx neutralization in the j774a.1 murine cell line. critical design features of this platform are 1) the application of a free-form or constrained 4 parameter logist ... | 2008 | 18304568 |
| experiments on army volunteers in israel will be overseen by the health ministry. | 2008 | 18309985 | |
| inhibitors of anthrax lethal factor based upon n-oleoyldopamine. | the structural features of an anthrax lethal factor inhibitor, n-oleoyldopamine (olda, 1) have been probed. the oleic acid moiety is critical, but, more interestingly, the presence of the double bond and its geometry were found to play an essential role. one compound, 5, was found to be an uncompetitive inhibitor of lethal factor (lf) with a k(i) value of 2.2microm and a cell-based ic(50) value of 4.3microm. | 2008 | 18314330 |
| etest for antibiotic susceptibility testing of bacillus anthracis, bacillus cereus and bacillus thuringiensis: evaluation of a french collection. | 2008 | 18316178 | |
| bacterial nitric-oxide synthases operate without a dedicated redox partner. | bacterial nitric-oxide (no) synthases (bnoss) are smaller than their mammalian counterparts. they lack an essential reductase domain that supplies electrons during no biosynthesis. this and other structural peculiarities have raised doubts about whether bnoss were capable of producing no in vivo. here we demonstrate that bnos enzymes from bacillus subtilis and bacillus anthracis do indeed produce no in living cells and accomplish this task by hijacking available cellular redox partners that are ... | 2008 | 18316370 |
| anamnestic protective immunity to bacillus anthracis is antibody mediated but independent of complement and fc receptors. | the threat of bioterrorist use of bacillus anthracis has focused urgent attention on the efficacy and mechanisms of protective immunity induced by available vaccines. however, the mechanisms of infection-induced immunity have been less well studied and defined. we used a combination of complement depletion along with immunodeficient mice and adoptive transfer approaches to determine the mechanisms of infection-induced protective immunity to b. anthracis. b- or t-cell-deficient mice lacked the co ... | 2008 | 18316379 |
| mitogen-activated protein kinase kinase signaling promotes growth and vascularization of fibrosarcoma. | we hypothesized that signaling through multiple mitogen-activated protein kinase (mapk) kinase (mkk) pathways is essential for the growth and vascularization of soft-tissue sarcomas, which are malignant tumors derived from mesenchymal tissues. we tested this using ht-1080, nci, and shac fibrosarcoma-derived cell lines and anthrax lethal toxin (letx), a bacterial toxin that inactivates mkks. western blots confirmed that letx treatment reduced the levels of phosphorylated extracellular signal-regu ... | 2008 | 18319331 |
| use of cethromycin, a new ketolide, for treatment of community-acquired respiratory infections. | the ketolides are a subclass of macrolides, which were designed specifically to overcome macrolide-resistant respiratory pathogens. ketolides lack the cladinose sugar, which is replaced with a 3-ketone group. ketolides bind to a secondary region on domain ii of the 23s rrna subunit. telithromycin was the first ketolide to be approved by the fda in 2004 for treatment of community-acquired pneumonia (cap), acute exacerbations of chronic bronchitis (aecb) and sinusitis. however, in 2006, after repo ... | 2008 | 18321237 |
| rapid point-of-care test to detect broad ranges of protective antigen-specific immunoglobulin g concentrations in recipients of the u.s.-licensed anthrax vaccine. | currently, there is no routine monitoring of an immune response to the anthrax vaccine. simple on-site tests are needed to evaluate the antibody response of anthrax-vaccinated individuals in the armed forces and others at high risk. using a prototype lateral flow assay (lfa) (r. e. biagini, d. l. sammons, j. p. smith, b. a. mackenzie, c. a. f. striley, j. e. snawder, s. a. robertson, and c. p. quinn, clin. vaccine immunol. 13:541-546, 2006), we investigated the agreement between a validated anth ... | 2008 | 18321882 |
| anthrax lethal toxin increases superoxide production in murine neutrophils via differential effects on mapk signaling pathways. | the combination of lethal factor and its receptor-binding partner, protective ag, is termed lethal toxin (lt) and has critical pathogenic activity during infection with bacillus anthracis. we herein report that anthrax lt binds and enters murine neutrophils, leading to the cleavage of mitogen-activated protein kinase kinase/mek/mapkk 1-4 and 6, but not mitogen-activated protein kinase kinase 5 and 7. anthrax lt treatment of neutrophils disrupts signaling to downstream mapk targets in response to ... | 2008 | 18322225 |
| macaque models of human infectious disease. | macaques have served as models for more than 70 human infectious diseases of diverse etiologies, including a multitude of agents-bacteria, viruses, fungi, parasites, prions. the remarkable diversity of human infectious diseases that have been modeled in the macaque includes global, childhood, and tropical diseases as well as newly emergent, sexually transmitted, oncogenic, degenerative neurologic, potential bioterrorism, and miscellaneous other diseases. historically, macaques played a major rol ... | 2008 | 18323583 |
| spin labelling of bacillus anthracis endospores: a model for in vivo tracking by epr imaging. | anthrax is caused by the gram-negative bacterium, bacillus anthracis. infection by this microbe results from delivery of the endospore form of the bacillus through direct contact, either topical or inhalation. with regard to the latter route of administration, it is proposed that endospores of b. anthracis enter the lungs and are phagocytized by host alveolar macrophages. thereafter, it is unclear as to how endospores travel to distal loci and what tissues are the targets. herein, this study des ... | 2008 | 18324523 |
| targeting mucosal dendritic cells with microbial antigens from probiotic lactic acid bacteria. | the use of vaccines against infectious microbes has been critical to the advancement of medicine. vaccine strategies combined with, or without, adjuvants have been established to eradicate various bacterial and viral pathogens. a new generation of vaccines is being developed using specific strains of gram-positive, lactic acid bacteria and, notably, some probiotic lactobacilli. these bacteria have been safely consumed by humans for centuries in fermented foods. thus, they can be orally administe ... | 2008 | 18324887 |
| inactivation kinetics of avirulent bacillus anthracis spores in milk with a combination of heat and hydrogen peroxide. | the combined effect of heat and hydrogen peroxide (hp) on the inactivation of avirulent bacillus anthracis spores (sterne strain 7702; strain anr-1, an avirulent ames derivative lacking the pxo2 plasmid; and strain 9131, a plasmid-less sterne strain) was evaluated in milk. the study temperature ranged from 90 to 95 degrees c, and the concentration of added hp varied from 0.05 to 0.5%. decimal reduction times (d-values) were determined using a sealed capillary tube technique. the mean d- and z-va ... | 2008 | 18326183 |
| molecular epidemiology of bacillus anthracis: determining the correct origin. | we analyzed and compared strains of bacillus anthracis isolated from husbandry and industrial anthrax cases in switzerland between 1952 and 1981 with published data using multiple-locus variable-number tandem repeat analysis. strains isolated from autochthonous cases of anthrax in cattle belong to genotype b2, together with strains from continental europe, while human b. anthracis strains clustered with genotype a4. these strains could be traced back to outbreaks of human anthrax that occurred b ... | 2008 | 18326672 |
| teichoic acids and related cell-wall glycopolymers in gram-positive physiology and host interactions. | most gram-positive bacteria incorporate membrane- or peptidoglycan-attached carbohydrate-based polymers into their cell envelopes. such cell-wall glycopolymers (cwgs) often have highly variable structures and have crucial roles in protecting, connecting and controlling the major envelope constituents. further important roles of cwgs in host-cell adhesion, inflammation and immune activation have also been described in recent years. identifying and harnessing highly conserved or species-specific s ... | 2008 | 18327271 |
| universal liposomes: preparation and usage for the detection of mrna. | dye-encapsulating liposomes can serve as signaling reagents in biosensors and biochemical assays in place of enzymes or fluorophores. detailed here is the use and preparation of streptavidin-coupled liposomes which offer a universal approach to biotinylated target detection. the universal approach provides two advantages, i.e. only one type of liposome is necessary despite varying target and probe sequences and the hybridization event can take place in the absence of potential steric hindrance o ... | 2008 | 18327569 |
| the conserved pa14 domain of cell wall-associated fungal adhesins governs their glycan-binding specificity. | yeast cell wall-associated, lectin-like adhesins form large families that mediate flocculation and host cell recognition. the glycan specificity of individual adhesins is largely unknown. zupancic et al. (this issue of molecular microbiology) used glycan microarrays to compare the glycan-binding characteristics of individual adhesins (epa proteins) of the pathogenic yeast candida glabrata produced in the non-adherent yeast saccharomyces cerevisiae. by sequence swapping between the conserved pa14 ... | 2008 | 18331471 |
| phenylalanine-427 of anthrax protective antigen functions in both pore formation and protein translocation. | the protective antigen (pa) moiety of anthrax toxin forms a heptameric pore in endosomal membranes of mammalian cells and translocates the enzymatic moieties of the toxin to the cytosol of these cells. phenylalanine-427 (f427), a solvent-exposed residue in the lumen of the pore, was identified earlier as being crucial for the transport function of pa. the seven f427 residues were shown in electrophysiological studies to form a clamp that catalyzes protein translocation through the pore. here, we ... | 2008 | 18334631 |
| a human antibody against anthrax protective antigen protects rabbits from lethal infection with aerosolized spores. | alxn4100, a fully human antibody that binds to the protective antigen of anthrax toxin, was generated from a fab isolated from a phage display library and was analyzed for its pharmacokinetic properties in rabbits and then used to protect rabbits from challenge with a lethal aerosol dose of bacillus anthracis spores (approximately 322x ld(50)). all rabbits receiving 15 or 40 mg/kg of antibody 24 hours before challenge survived; survival of rabbits receiving 4 mg/kg either subcutaneously or intra ... | 2007 | 18334745 |
| low molecular weight inhibitors of the protease anthrax lethal factor. | anthrax lethal factor (lf) is a zinc-dependent metalloprotease that together with the protective antigen constitute the anthrax lethal toxin, the most prominent virulence factor of the disease anthrax. this review summarizes the current knowledge on anthrax toxicity and defense in relation to lf. particular emphasis is placed on the structural aspects of lf, the properties of its substrates and the achievements in the design of low molecular weight inhibitors of the catalytic activity of the met ... | 2008 | 18336349 |
| anthrax lethal toxin and salmonella elicit the common cell death pathway of caspase-1-dependent pyroptosis via distinct mechanisms. | caspase-1 cleaves the inactive il-1beta and il-18 precursors into active inflammatory cytokines. in salmonella-infected macrophages, caspase-1 also mediates a pathway of proinflammatory programmed cell death termed "pyroptosis." we demonstrate active caspase-1 diffusely distributed in the cytoplasm and localized in discrete foci within macrophages responding to either salmonella infection or intoxication by bacillus anthracis lethal toxin (lt). both stimuli triggered caspase-1-dependent lysis in ... | 2008 | 18337499 |
| bacillus spore classification via surface-enhanced raman spectroscopy and principal component analysis. | surface-enhanced raman spectroscopy (sers) can provide rapid fingerprinting of biomaterial in a nondestructive manner. the adsorption of colloidal silver to biological material suppresses native biofluorescence while providing electromagnetic surface enhancement of the normal raman signal. this work validates the applicability of qualitative ser spectroscopy for analysis of bacterial species by utilizing principal component analysis (pca) to show discrimination of biological threat simulants, ba ... | 2008 | 18339232 |
| genome assembly forensics: finding the elusive mis-assembly. | we present the first collection of tools aimed at automated genome assembly validation. this work formalizes several mechanisms for detecting mis-assemblies, and describes their implementation in our automated validation pipeline, called amosvalidate. we demonstrate the application of our pipeline in both bacterial and eukaryotic genome assemblies, and highlight several assembly errors in both draft and finished genomes. the software described is compatible with common assembly formats and is re ... | 2008 | 18341692 |
| examination of intrinsic sulfonamide resistance in bacillus anthracis: a novel assay for dihydropteroate synthase. | dihydropteroate synthase (dhps) catalyzes the formation of dihydropteroate and mg-pyrophosphate from 6-hydroxymethyl-7,8-dihydropterin diphosphate and para-aminobenzoic acid. the bacillus anthracis dhps is intrinsically resistant to sulfonamides. however, using a radioassay that monitors the dihydropteroate product, the enzyme was inhibited by the same sulfonamides. a continuous spectrophotometric assay for measuring the enzymatic activity of dhps was developed and used to examine the effects of ... | 2008 | 18342015 |
| both cd4+ and cd8+ t cells respond to antigens fused to anthrax lethal toxin. | the lethal toxin produced by bacillus anthracis is a bipartite toxin in which the first protein, protective antigen (pa), transports the second protein, lethal factor, across the host cell membrane. we have previously shown that cd8(+) t-cell epitopes fused to a nontoxic derivative of lethal factor (lfn) are delivered into the host cell cytosol in a pa-dependent manner. delivery of these antigens targets them to the intracellular major histocompatibility complex (mhc) class i processing and pres ... | 2008 | 18347032 |
| modeling the logistics of response to anthrax bioterrorism. | a bioterrorism attack with an agent such as anthrax will require rapid deployment of medical and pharmaceutical supplies to exposed individuals. how should such a logistical system be organized? how much capacity should be built into each element of the bioterrorism response supply chain? | 2008 | 18349432 |
| evidence against a human cell-specific role for lrp6 in anthrax toxin entry. | the role of the cellular protein lrp6 in anthrax toxin entry is controversial. previous studies showed that lrp6 was important for efficient intoxication of human m2182 prostate carcinoma cells but other studies performed with cells from gene-knockout mice demonstrated no role for either lrp6 or the related lrp5 protein in anthrax toxin entry. one possible explanation for this discrepancy is that lrp6 may be important for anthrax toxin entry into human, but not mouse, cells. to test this idea we ... | 2008 | 18350154 |
| application of in vivo induced antigen technology (iviat) to bacillus anthracis. | in vivo induced antigen technology (iviat) is an immuno-screening technique that identifies bacterial antigens expressed during infection and not during standard in vitro culturing conditions. we applied iviat to bacillus anthracis and identified paga, seven members of a n-acetylmuramoyl-l-alanine amidase autolysin family, three p60 family lipoproteins, two transporters, spore cortex lytic protein sleb, a penicillin binding protein, a putative prophage holin, respiratory nitrate reductase narg, ... | 2008 | 18350160 |
| copi coatomer complex proteins facilitate the translocation of anthrax lethal factor across vesicular membranes in vitro. | the delivery of the diphtheria toxin catalytic domain (dta) from acidified endosomes into the cytoplasm of eukaryotic cells requires protein-protein interactions between the toxin and a cytosolic translocation factor (ctf) complex. a conserved peptide motif, t1, within the dt transmembrane helix 1 mediates these interactions. because the t1 motif is also present in the n-terminal segments of lethal factor (lf) and edema factor (ef) in anthrax toxin, we asked whether lf entry into the cell might ... | 2008 | 18356299 |
| the systemic administration of lethal toxin achieves a growth delay of human melanoma and neuroblastoma xenografts: assessment of receptor contribution. | two of the three components of anthrax toxin, protective antigen (pa) and lethal factor (lf), together known as lethal toxin (letx), reportedly show anti-tumor activity in melanoma in vitro and in vivo. the growth inhibitory activity of letx in culture was determined in nine human cancer cell lines, including melanoma, neuroblastoma and adenocarcinoma cells, as well as in human umbilical vein endothelial cells (huvec). the contribution of the two known pa receptor proteins, antxr1/tem8 and antxr ... | 2008 | 18360701 |
| [pathology of inoculation]. | 2008 | 18361288 | |
| high resolution genotyping of bacillus anthracis outbreak strains using four highly mutable single nucleotide repeat markers. | bacillus anthracis is a genetically monomorphic bacterium with little diversity to be expected during an outbreak. this study used more rapidly evolving genetic markers on outbreak samples to ascertain genetic diversity. | 2008 | 18363651 |
| bsla, a pxo1-encoded adhesin of bacillus anthracis. | the gram-positive pathogen bacillus anthracis causes anthrax, a fulminant and lethal infection of mammals. two large virulence plasmids, pxo1 and pxo2, harbour genes required for anthrax pathogenesis and encode secreted toxins or provide for the poly gamma-d-glutamic acid capsule. in addition to capsule, b. anthracis harbours additional cell wall envelope structures, including the surface layer (s-layer), which is composed of crystalline protein arrays. we sought to identify the b. anthracis env ... | 2008 | 18366441 |
| rapid polymerase chain reaction-based screening assay for bacterial biothreat agents. | to design and evaluate a rapid polymerase chain reaction (pcr)-based assay for detecting eubacteria and performing early screening for selected class a biothreat bacterial pathogens. | 2008 | 18370996 |
| commingling regulatory systems following acquisition of virulence plasmids by bacillus anthracis. | the conversion of a bacterium from a non-pathogenic to a pathogenic existence is usually associated with the acquisition of virulence factors, the genes of which gain entry through bacteriophage infection, transposable elements or plasmid transfer. pathogenesis research is mostly focused on how these factors enable the bacterium to infect the host or evade the repertoire of host defenses. less effort is expended on understanding how the invading genes are affected by the complex regulatory circu ... | 2008 | 18374574 |
| bacillus anthracis: balancing innocent research with dual-use potential. | anthrax euronet, a coordination action of the eu 6th framework programme, was designed to strengthen networking activities between anthrax research groups in europe and to harmonise protocols for testing anthrax vaccines and therapeutics. inevitably, the project also addressed aspects of the current political issues of biosecurity and dual-use research, i.e. research into agents of important diseases of man, livestock or agriculture that could be used as agents of bioterrorism. this review provi ... | 2008 | 18375178 |
| in vivo efficacy of beta-cyclodextrin derivatives against anthrax lethal toxin. | we evaluated the in vivo efficacy of three beta-cyclodextrin derivatives that block the anthrax protective antigen pore. these compounds were at least 15-fold more potent than previously described beta-cyclodextrins in protecting against anthrax lethal toxin in a rat model. one of the drugs was shown to protect mice from bacterial infection. | 2008 | 18378717 |
| comparison of the essential cellular functions of the two mura genes of bacillus anthracis. | targeted antisense and gene replacement mutagenesis experiments demonstrate that only the mura1 gene and not the mura2 gene is required for the normal cellular growth of bacillus anthracis. antisense-based modulation of mura1 gene expression hypersensitizes cells to the mura-specific antibiotic fosfomycin despite the normally high resistance of b. anthracis to this drug. | 2008 | 18378720 |
| profile: interview with rajeev venkayya, md, director, global health delivery, bill & melinda gates foundation, and former special assistant to the president and senior director for biodefense, white house homeland security council. | 2008 | 18386969 | |
| implementing the cities readiness initiative: lessons learned from boston. | the federally funded cities readiness initiative (cri) requires seamless federal, state, and local public health coordination to provide antibiotics to an entire city population within 48 hours of an aerosolized release of anthrax. we document practical lessons learned from the development and implementation of the boston cri plan. key themes center on heightened emphasis on security, a new mass protection model of dispensing, neighborhood-centric clinic site selection, online training of medica ... | 2008 | 18388657 |
| decontamination of fluid milk containing bacillus spores using commercial household products. | although commercial sanitizers can inactivate bacterial spores in food processing environments, relatively little data exist as to the decontamination of products and surfaces by consumers using commercial household products. should a large scale bioterrorism incident occur in which consumer food products were contaminated with a pathogenic sporeformer such as bacillus anthracis, there may be a need to decontaminate these products before disposal as liquid or solid waste. studies were conducted ... | 2008 | 18389688 |
| anthrax in saskatchewan 2006: an outbreak overview. | 2008 | 18390096 | |
| bioterrorism: class a agents and their potential presentations in immunocompromised patients. | a bioterrorism attack would be particularly challenging for medical professionals caring for patients with cancer who often have weakened immune systems. knowledge of the class a agents and the potential variable presentations in immunocompromised patients is key to early recognition of an outbreak and prompt reporting. the purpose of this article is to present the class a agents: bacillus anthracis (anthrax), botulinum toxin (botulism), variola virus (smallpox), yersinia pestis (pneumonic plagu ... | 2008 | 18390465 |
| inactivation of bacillus anthracis spores by a combination of biocides and heating under high-temperature short-time pasteurization conditions. | the milk supply is considered a primary route for a bioterrorism attack with bacillus anthracis spores because typical high-temperature short-time (htst) pasteurization conditions cannot inactivate spores. in the event of intentional contamination, an effective method to inactivate the spores in milk under htst processing conditions is needed. this study was undertaken to identify combinations and concentrations of biocides that can inactivate b. anthracis spores at temperatures in the htst rang ... | 2008 | 18390680 |
| bayesian-integrated microbial forensics. | in the aftermath of the 2001 anthrax letters, researchers have been exploring ways to predict the production environment of unknown-source microorganisms. culture medium, presence of agar, culturing temperature, and drying method are just some of the broad spectrum of characteristics an investigator might like to infer. the effects of many of these factors on microorganisms are not well understood, but the complex way in which microbes interact with their environments suggests that numerous anal ... | 2008 | 18390682 |
| conference report on public health and clinical guidelines for anthrax. | on march 13-14, 2006, a meeting on anthrax, sponsored by the centers for disease control and prevention (cdc) in collaboration with the southeastern center for emerging biologic threats, was held at emory university in atlanta, georgia, usa. the meeting's agenda included discussion of postexposure prophylaxis (pep), screening and evaluation, and treatment of the various manifestations of human anthrax. the goal was to convene subject matter experts for a review of research developments and clini ... | 2008 | 18394267 |
| single nucleotide polymorphism typing of bacillus anthracis from sverdlovsk tissue. | a small number of conserved canonical single nucleotide polymorphisms (cansnp) that define major phylogenetic branches for bacillus anthracis were used to place a sverdlovsk patient's b. anthracis genotype into 1 of 12 subgroups. reconstruction of the paga gene also showed a unique snp that defines a new lineage for b. anthracis. | 2008 | 18394287 |
| real time detection of anthrax spores using highly specific anti-ea1 recombinant antibodies produced by competitive panning. | we describe a targeted approach for the production of biological recognition elements capable of fast, specific detection of anthrax spores on biosensor surfaces. the aim was to produce single chain antibodies (scfvs) to ea1, a bacillus anthracis s-layer protein that is also present, although not identical, in related to bacillus species. the aim of the work was to produce antibodies that would detect b. anthracis ea1 protein and intact spores with a high degree of specificity, but would not det ... | 2008 | 18395220 |
| development of a rapid and sensitive immunoassay for detection and subsequent recovery of bacillus anthracis spores in environmental samples. | bacillus anthracis is considered a major threat as an agent of bioterrorism. b. anthracis spores are readily dispersed as aerosols, are very persistent, and are resistant to normal disinfection treatments. immunoassays have been developed to rapidly detect b. anthracis spores at high concentrations. however, detection of b. anthracis spores at lower concentrations is problematic due to the fact that closely related bacillus species (e.g., b. thuringiensis) can cross-react with anti-b. anthracis ... | 2008 | 18395279 |
| modeling the inactivation kinetics of bacillus spores by glutaraldehyde. | our goal was to develop a mathematical kinetic model to predict the sporicidal activity of glutaraldehyde, which is an active ingredient frequently used in commercial products employed for liquid disinfection and decontamination. | 2008 | 18397220 |
| pyridine nucleotide complexes with bacillus anthracis coenzyme a-disulfide reductase: a structural analysis of dual nad(p)h specificity. | we have recently reported that coash is the major low-molecular weight thiol in bacillus anthracis [nicely, n. i. , parsonage, d., paige, c., newton, g. l., fahey, r. c., leonardi, r., jackowski, s., mallett, t. c., and claiborne, a. (2007) biochemistry 46, 3234-3245], and we have now characterized the kinetic and redox properties of the b. anthracis coenzyme a-disulfide reductase (coadr, bacoadr) and determined the crystal structure at 2.30 a resolution. while the staphylococcus aureus and borr ... | 2008 | 18399646 |
| [healthcare response to bioterrorism]. | bioterrorists seek to use highly virulent pathogens to cause social and economic disruption. historical agents such as anthrax, yersinia pestis and botulinum toxin can easily be produced, whereas others such as hemorragic fever virus require much more sophisticated infrastructure and government-scale resources. in the near future, with the spread of new biotechnologies, bioterrorists may produce new transgenic pathogens. epidemiological surveillance and diagnostic capacities should thus be more ... | 2007 | 18402160 |
| function, structure and regulation of the vacuolar (h+)-atpases. | the vacuolar atpases (or v-atpases) are atp-driven proton pumps that function to both acidify intracellular compartments and to transport protons across the plasma membrane. intracellular v-atpases function in such normal cellular processes as receptor-mediated endocytosis, intracellular membrane traffic, prohormone processing, protein degradation and neurotransmitter uptake, as well as in disease processes, including infection by influenza and other viruses and killing of cells by anthrax and d ... | 2008 | 18406336 |
| infectious agents of bioterrorism: a review for emergency physicians. | the terrorist attacks on the united states in 2001 and the anthrax release soon after brought the issue of bioterrorism to the forefront in the medical community. bioterrorism is the use of a biologic weapon to create terror and panic. biologic weapons, or bioweapons, can be bacteria, fungi, viruses, or biologic toxins. because the emergency department represents the front line of defense for the recognition of agents of bioterrorism, it is essential that emergency physicians have the ability to ... | 2008 | 18406986 |
| biological and biochemical characterization of anthrax lethal factor, a proteolytic inhibitor of mek signaling pathways. | the secretion of factors that block critical intracellular signaling pathways is a common strategy used by pathogenic bacteria for disabling host defenses and causing disease. anthrax lethal toxin (letx) has been shown to cleave and inactivate mitogen-activated protein kinase (mapk) kinases (mkks or meks) and to inhibit mkk signaling. cleavage of mkks by letx prevents activation of their downstream substrates, the mapks. because mapk pathways regulate a variety of crucial cellular functions incl ... | 2008 | 18413261 |
| high-level expression and single-step purification of recombinant bacillus anthracis protective antigen from escherichia coli. | pa (protective antigen) is a major immunogen of the vaccine against anthrax. in the present study, a new expression system, escherichia coli strain rosetta 2(de3), was used for high-level expression of rpa (recombinant pa) whose gene contains 66 rare e. coli codons (9.0% of 733 total pa gene codons). the rpa-formed inclusion bodies were washed with triton x-100 and 2 m urea and solubilized in 5 m urea, followed by a 60%-satd.-ammonium sulfate precipitation. finally, the untagged rpa was efficien ... | 2009 | 18416696 |
| interlaboratory comparison of results of an anthrax lethal toxin neutralization assay for assessment of functional antibodies in multiple species. | the anthrax lethal toxin neutralization assay (tna) will likely be used to correlate the protection offered by new anthrax vaccines in animal models to the immunogenicity that will be provided in humans. tna data are being generated in several different laboratories to measure the immune responses in rabbits, nonhuman primates, and humans. in order to compare data among species and laboratories, a collaborative study was conducted in which 108 samples from the three species were analyzed in seve ... | 2008 | 18417668 |
| from soil to gut: bacillus cereus and its food poisoning toxins. | bacillus cereus is widespread in nature and frequently isolated from soil and growing plants, but it is also well adapted for growth in the intestinal tract of insects and mammals. from these habitats it is easily spread to foods, where it may cause an emetic or a diarrhoeal type of food-associated illness that is becoming increasingly important in the industrialized world. the emetic disease is a food intoxication caused by cereulide, a small ring-formed dodecadepsipeptide. similar to the virul ... | 2008 | 18422617 |
| identification of oxidative stress and toll-like receptor 4 signaling as a key pathway of acute lung injury. | multiple lung pathogens such as chemical agents, h5n1 avian flu, or sars cause high lethality due to acute respiratory distress syndrome. here we report that toll-like receptor 4 (tlr4) mutant mice display natural resistance to acid-induced acute lung injury (ali). we show that tlr4-trif-traf6 signaling is a key disease pathway that controls the severity of ali. the oxidized phospholipid (oxpl) oxpapc was identified to induce lung injury and cytokine production by lung macrophages via tlr4-trif. ... | 2008 | 18423196 |
| improvement of an antibody neutralizing the anthrax toxin by simultaneous mutagenesis of its six hypervariable loops. | the enhancement of antibody affinity by mutagenesis targeting only complementarity determining regions has the advantage of respecting the framework regions, which are important for tolerance if clinical use is envisaged. here, starting from a fab (antigen-binding fragment; 35pa(83)) capable of neutralizing the lethal toxin of anthrax and having an affinity of 3.4 nm for its antigen, a phage-displayed library of variants where all six complementarity determining regions (73 positions) were targe ... | 2008 | 18423488 |
| mast cell activators: a new class of highly effective vaccine adjuvants. | mast cells (mcs) have recently received recognition as prominent effectors in the regulation of immune cell migration to draining lymph nodes and lymphocyte activation. however, their role in the development of humoral immune responses is not clear. here, we demonstrate that subcutaneous or nasal administration of small-molecule mc activators with vaccine antigens evokes large increases in antigen-specific serum immunoglobulin g (igg) responses. these responses were mc dependent and correlated w ... | 2008 | 18425129 |