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genetic variation and linkage disequilibrium in bacillus anthracis.we performed whole-genome amplification followed by hybridization of custom-designed resequencing arrays to resequence 303 kb of genomic sequence from a worldwide panel of 39 bacillus anthracis strains. we used an efficient algorithm contained within a custom software program, uniquemer, to identify and mask repetitive sequences on the resequencing array to reduce false-positive identification of genetic variation, which can arise from cross-hybridization. we discovered a total of 240 single nuc ...201122355684
[necrotic lesion of the lip and cough with fever: cutaneous and pulmonary anthrax].anthrax disease is an anthropozoonosis caused by bacillus anthracis. it appears in three clinical forms: pulmonary, intestinal, and cutaneous. we report a case of pulmonary and cutaneous anthrax in a one-year-old moroccan infant.201122393634
predictability of anthrax infection in the serengeti, tanzania.anthrax is endemic throughout africa, causing considerable livestock and wildlife losses and severe, sometimes fatal, infection in humans. predicting the risk of infection is therefore important for public health, wildlife conservation and livestock economies. however, because of the intermittent and variable nature of anthrax outbreaks, associated environmental and climatic conditions, and diversity of species affected, the ecology of this multihost pathogen is poorly understood.we explored rec ...201122318563
the pore-forming protein cry5b elicits the pathogenicity of bacillus sp. against caenorhabditis elegans.the soil bacterium bacillus thuringiensis is a pathogen of insects and nematodes and is very closely related to, if not the same species as, bacillus cereus and bacillus anthracis. the defining characteristic of b. thuringiensis that sets it apart from b. cereus and b. anthracis is the production of crystal (cry) proteins, which are pore-forming toxins or pore-forming proteins (pfps). although it is known that pfps are important virulence factors since their elimination results in reduced virule ...201122216181
knowledge and attitude towards zoonoses among animal health workers and livestock keepers in arusha and tanga, tanzania.zoonoses are infections naturally transmitted between vertebrate animals and humans. an exploratory questionnaire-based survey of animal health workers(n=36) and livestock keepers(n=43) was carried out from april 2001 to march 2002 in tanga and arusha regions, northern tanzania, to assess local knowledge, attitudes and public awareness for animal zoonoses. a combination of closed and open-ended questions, focus group discussions and ranking techniques were employed to gather information on perce ...201024409636
multiplex pcr assay for the detection of enterotoxic bacillus cereus group strains and its application in food matrices.bacillus cereus, bacillus thuringiensis and bacillus anthracis are the major concerns for the food safety in terms of frequency and/or seriousness of the disease. being members of the same group and sharing dna homology to a larger extent, they do create problems when their specific detection/identification is attempted from different food and environmental sources. numerous individual polymerase chain reaction (pcr) and few multiplex pcr (mpcr) methods have been employed to detect these organis ...201023100823
multiplexed electrochemical detection of yersinia pestis and staphylococcal enterotoxin b using an antibody microarray.the combimatrix antibody microarray is a versatile, sensitive detection platform based on the generation and transduction of electrochemical signals following antigen binding to surface antibodies. the sensor chip described herein is comprised of microelectrodes coupled to an adjacent bio-friendly matrix coated with antibodies to the biological pathogens yersinia pestis and bacillus anthracis, and the bacterial toxin staphylococcal enterotoxin b (seb). using this system, we were able to detect s ...201022319302
binary fingerprints at fluctuation-enhanced sensing.we have developed a simple way to generate binary patterns based on spectral slopes in different frequency ranges at fluctuation-enhanced sensing. such patterns can be considered as binary "fingerprints" of odors. the method has experimentally been demonstrated with a commercial semiconducting metal oxide (taguchi) sensor exposed to bacterial odors (escherichia coli and anthrax-surrogate bacillus subtilis) and processing their stochastic signals. with a single taguchi sensor, the situations of e ...201022315545
remediating office environments of spore-forming bacteria.this study examines decontamination processes that were developed on an emergency basis to eliminate bacillus anthracis spores from deliberately contaminated buildings. the recommended steps include a survey with sampling, the removal of sensitive items, and hepa vacuuming of all readily available surfaces, followed by biocide treatment and subsequent analyses for viable cells. there are several analytical challenges posed by this approach. these include the ability to discriminate the added str ...201020737349
an ultra-high temperature flow-through capillary device for bacterial spore lysis.rapid and specific characterization of bacterial endospores is dependent on the ability to rupture the cell wall to enable analysis of the intracellular components. in particular, bacterial spores from the bacillus genus are inherently robust and very difficult to lyze or solubilize. standard protocols for spore inactivation include chemical treatment, sonication, pressure, and thermal lysis. although these protocols are effective for the inactivation of these agents, they are less well suited f ...201020737447
vaccination of rhesus macaques with the anthrax vaccine adsorbed vaccine produces a serum antibody response that effectively neutralizes receptor-bound protective antigen in vitro.anthrax toxin (atx) is composed of the binary exotoxins lethal toxin (ltx) and edema toxin (etx). they have separate effector proteins (edema factor and lethal factor) but have the same binding protein, protective antigen (pa). pa is the primary immunogen in the current licensed vaccine anthrax vaccine adsorbed (ava [biothrax]). ava confers protective immunity by stimulating production of atx-neutralizing antibodies, which could block the intoxication process at several steps (binding of pa to t ...201020739500
decontamination options for bacillus anthracis-contaminated drinking water determined from spore surrogate studies.five parameters were evaluated with surrogates of bacillus anthracis spores to determine effective decontamination alternatives for use in a contaminated drinking water supply. the parameters were as follows: (i) type of bacillus spore surrogate (b. thuringiensis or b. atrophaeus), (ii) spore concentration in suspension (10(2) and 10(6) spores/ml), (iii) chemical characteristics of the decontaminant (sodium dichloro-s-triazinetrione dihydrate [dichlor], hydrogen peroxide, potassium peroxymonosul ...201020709855
the human-bacterial pathogen protein interaction networks of bacillus anthracis, francisella tularensis, and yersinia pestis.bacillus anthracis, francisella tularensis, and yersinia pestis are bacterial pathogens that can cause anthrax, lethal acute pneumonic disease, and bubonic plague, respectively, and are listed as niaid category a priority pathogens for possible use as biological weapons. however, the interactions between human proteins and proteins in these bacteria remain poorly characterized leading to an incomplete understanding of their pathogenesis and mechanisms of immune evasion.201020711500
a chimeric protein that functions as both an anthrax dual-target antitoxin and a trivalent vaccine.effective measures for the prophylaxis and treatment of anthrax are still required for counteracting the threat posed by inhalation anthrax. in this study, we first demonstrated that the chimeric protein lfn-pa, created by fusing the protective antigen (pa)-binding domain of lethal factor (lfn) to pa, retained the functions of the respective molecules. on the basis of this observation, we attempted to develop an antitoxin that targets the binding of lethal factor (lf) and/or edema factor (ef) to ...201020713663
heterodimeric integrin complexes containing beta1-integrin promote internalization and lethality of anthrax toxin.to kill macrophages, the lethal factor component of bacillus anthracis toxin binds to a carrier protein (pa), which then interacts with the cmg2 receptor protein on the cell surface and is endocytosed into the cytoplasm. cmg2, as well as tem8, a second pa receptor not present on macrophages, contain a von willebrand a domain that is crucial for toxin binding. here we report that integrin beta1, another cell surface von willebrand a domain protein, can mediate and potentiate anthrax toxin endocyt ...201020713715
[biological weapons].biological weapons are weapons of mass destruction that use pathogens (bacteria, viruses) or the toxins produced by them to target living organisms or to contaminate non-living substances. in the past, biological warfare has been repeatedly used. anthrax, plague and smallpox are regarded as the most dangerous biological weapons by various institutions. nowadays it seems quite unlikely that biological warfare will be employed in any military campaigns. however, the possibility remains that biolog ...201020717866
targeted expression of anthrax protective antigen by lactobacillus gasseri as an anthrax vaccine.induction of protective immunity against pathogenic microbes, including bacillus anthracis, requires efficient vaccines that potentiate antibody avidity and increase t-cell longevity. we recently reported that the delivery of targeted b. anthracis protective antigen (pa) genetically fused to a dc-binding peptide (dcpep) by lactobacillus acidophilus induced mucosal and systemic immunity against b. anthracis challenge in mice.201020722604
effective induction of protective systemic immunity with nasally administered vaccines adjuvanted with il-1.il-1α and il-1β were evaluated for their ability to provide adjuvant activity for the induction of serum antibody responses when nasally administered with protein antigens in mice and rabbits. in mice, intranasal (i.n.) immunization with pneumococcal surface protein a (pspa) or tetanus toxoid (tt) combined with il-1β induced protective immunity that was equivalent to that induced by parenteral immunization. nasal immunization of awake (i.e., not anesthetized) rabbits with il-1-adjuvanted vaccine ...201020723629
insilico studies on anthrax lethal factor inhibitors: pharmacophore modeling and virtual screening approaches towards designing of novel inhibitors for a killer.bacillus anthracis is a causative organism of anthrax. the main reason to use anthrax as a bioweapon is the combination of the spore's durability and the lethal toxaemia of the vegetative stage. in anthrax infection, lethal factor (lf) is playing crucial role in causing cell death, by inhibiting pathways that rely on this kinase family. the combination of vaccine and antibiotics is preferred as an effective treatment for this target. till date, no small molecule inhibitor is identified as a drug ...201020727800
surface localized and extracellular glyceraldehyde-3-phosphate dehydrogenase of bacillus anthracis is a plasminogen binding protein.the role of anchorless proteins on the surface of most pathogenic microorganisms has long been studied in context to their interactions with multiple host proteins, facilitating the dissemination of pathogen within the host tissues. in order to gain more insights into anthrax pathogenesis, we hereby report the presence of a prominent moonlighting enzyme, glyceraldehyde-3-phosphate dehydrogenase (gapdh) on the surface and in the extracellular medium of bacillus anthracis. out of the three heterol ...201020727989
mutational analysis of bacillus megaterium qm b1551 cortex-lytic enzymes.molecular-genetic and muropeptide analysis techniques have been applied to examine the function in vivo of the bacillus megaterium qm b1551 sleb and slel proteins. in common with bacillus subtilis and bacillus anthracis, the presence of anhydromuropeptides in b. megaterium germination exudates, which is indicative of lytic transglycosylase activity, is associated with an intact sleb structural gene. b. megaterium sleb cwlj double mutant strains complemented with engineered sleb variants in which ...201020729357
[current views on pathogenicity and immunogenicity factors of bacillus anthracis].bacillus anthracis is an etiological agent of extremely dangerous zooanthroponosis - anthrax. to date, significant volume of scientific data about structure, molecular nature, characteristics, genetic determination, regulation and action mechanisms of main pathogenicity factors of b. anthracis and its immunogenicity is accumulated. for study of integral picture ofpathogenesis and immunogenesis such global methodologies as complex analysis of structure and functions ofgenome, on the one hand, and ...201020734727
analytical particle measurements in an optical microflume.in this work, microscopic particles in a fluid flow are manipulated using forces generated by a high power laser beam. the resulting manipulations on the particles are imaged using a microscope lens connected to a ccd camera. differential forces on particles of varying physical and chemical composition have been measured. the goal is to measure the optical forces on a diverse range of particles and catalog the associated chemical and physical differences to understand which properties and mechan ...201020685420
amyloid peptide pores and the beta sheet conformation.over 20 clinical syndromes have been described as amyloid diseases. pathologically, these illnesses are characterized by the deposition in various tissues of amorphous, congo red stainingdeposits, referred to as amyloid. under polarizing light microscopy, these deposits exhibit characteristic green birefringence. x-ray diffraction reveals cross-beta structure of extended amyloid fibrils. although there is always a major protein in amyloid deposits, the predominant protein differs in each ofthe c ...201020687488
confirmation of bacillus anthracis from flesh-eating flies collected during a west texas anthrax season.this case study confirms the interaction between necrophilic flies and white-tailed deer, odocoileus virginianus, during an anthrax outbreak in west texas (summer 2005). bacillus anthracis was identified by culture and pcr from one of eight pooled fly collections from deer carcasses on a deer ranch with a well-documented history of anthrax. these results provide the first known isolation of b. anthracis from flesh-eating flies associated with a wildlife anthrax outbreak in north america and are ...201020688697
activation of the latent plcr regulon in bacillus anthracis.many genes in bacillus cereus and bacillus thuringiensis are under the control of the transcriptional regulator plcr and its regulatory peptide, papr. in bacillus anthracis, the causative agent of anthrax, plcr is inactivated by truncation, and consequently genes having plcr binding sites are expressed at very low levels when compared with b. cereus. we found that activation of the plcr regulon in b. anthracis by expression of a plcr-papr fusion protein does not alter sporulation in strains cont ...201020688829
oculocutaneous anthrax: detection and treatment.anthrax, a zoonotic disease that primarily affects herbivores, has received recent attention as a potential agent of bioterrorism. we report a patient who presented with a 4-day history of pain, watering and difficulty in opening the left upper and lower eyelids, and fever. clinical examination revealed brawny nonpitting edema with serosanguinous discharge. the history of the death of his sheep 1 week prior to the illness provided the clue to the diagnosis. although standard cultures of the bloo ...201020689787
anthrax toxin receptor 1/tumor endothelial marker 8: mutation of conserved inserted domain residues overrides cytosolic control of protective antigen binding.anthrax toxin receptor 1 (antxr1)/tumor endothelial marker 8 (tem8) is one of two known proteinaceous cell surface anthrax toxin receptors. a metal ion dependent adhesion site (midas) present in the integrin-like inserted (i) domain of antxr1 mediates the binding of the anthrax toxin subunit, protective antigen (pa). here we provide evidence that single point mutations in the i domain can override regulation of antxr1 ligand-binding activity mediated by intracellular signals. a previously report ...201020690680
an anthrax subunit vaccine candidate based on protective regions of bacillus anthracis protective antigen and lethal factor.studies have confirmed the key role of bacillus anthracis protective antigen (pa) in the us and uk human anthrax vaccines. however, given the tripartite nature of the toxin, other components, including lethal factor (lf), are also likely to contribute to protection. we examined the antibody and t cell responses to pa and lf in human volunteers immunized with the uk anthrax vaccine (avp). individual lf domains were assessed for immunogenicity in mice when given alone or with pa. based on the resu ...201020691267
characterisation and evaluation of synthetic antimicrobial peptides against bacillus globigii, bacillus anthracis and burkholderia thailandensis.antimicrobial peptides (amps) are produced by all forms of living organisms and represent a novel class of antibiotics to treat infectious diseases. in this study, 29 amps of varying length and characteristics were synthesised chemically and were evaluated for their ability to inhibit the growth of bacillus globigii, bacillus anthracis and burkholderia thailandensis. amongst the peptides tested, sheep myeloid antimicrobial peptide-29 (smap-29) was the most potent, inhibiting both b. globigii and ...201020692130
issues in biosecurity and biosafety.the role of non-governmental organisations and other interested observers - civil society - has long been neglected by governments in the quest for a world secure from the threat of biological weapons or bioterrorism. new trends illustrate a greater appreciation of a strong need for a cooperative partnership. governments need to accept and embrace some of these new trends and new technologies. at least since 2001 and the amerithrax anthrax letters, the usa has had a significant focus on biosecur ...201020696555
a synthetic peptide vaccine directed against the 2ß2-2ß3 loop of domain 2 of protective antigen protects rabbits from inhalation anthrax.the current vaccines for anthrax in the united states and united kingdom are efficacious in the two most accepted animal models of inhalation anthrax, nonhuman primates and rabbits, but require extensive immunization protocols. we previously demonstrated that a linear determinant in domain 2 of bacillus anthracis protective ag (pa) is a potentially important target for an epitope-specific vaccine for anthrax, as abs specific for this site, referred to as the loop-neutralizing determinant (lnd), ...201020696862
human transferrin confers serum resistance against bacillus anthracis.the innate immune system in humans consists of both cellular and humoral components that collaborate to eradicate invading bacteria from the body. here, we discover that the gram-positive bacterium bacillus anthracis, the causative agent of anthrax, does not grow in human serum. fractionation of serum by gel filtration chromatography led to the identification of human transferrin as the inhibiting factor. purified transferrin blocks growth of both the fully virulent encapsulated b. anthracis ame ...201020615872
the resistance of bacillus atrophaeus spores to the bactericidal activity of peracetic acid is influenced by both the nature of the solid substrates and the mode of contamination.to evaluate the impact of the mode of contamination in relation with the nature of solid substrates on the resistance of spores of bacillus atrophaeus -selected as surrogates of bacillus anthracis- to a disinfectant, peracetic acid.201020618887
mucosal priming of newborn mice with s. typhi ty21a expressing anthrax protective antigen (pa) followed by parenteral pa-boost induces b and t cell-mediated immunity that protects against infection bypassing maternal antibodies.the currently licensed anthrax vaccine has several limitations and its efficacy has been proven only in adults. effective immunization of newborns and infants requires adequate stimulation of their immune system, which is competent but not fully activated. we explored the use of the licensed live attenuated s. typhi vaccine strain ty21a expressing bacillus anthracis protective antigen [ty21a(pa)] followed pa-alum as a strategy for immunizing the pediatric population. newborn mice primed with a s ...201020619377
rapid sporulation of bacillus anthracis in a high iron, glucose-free medium.spores are the infectious form of bacillus anthracis (ba), causing cutaneous, inhalation and gastrointestinal anthrax. because of the possible use of ba spores in a bioterrorism attack, there is considerable interest in studying spore biology. in the laboratory, however, it takes a number of days to prepare spores. standard sporulation protocols, such as the use of 'pa broth', allow sporulation of ba to occur in 3 to 5 days. another method employs growth of ba on plates in the dark for several d ...201020621133
setting risk-informed environmental standards for bacillus anthracis spores.in many cases, human health risk from biological agents is associated with aerosol exposures. because air concentrations decline rapidly after a release, it may be necessary to use concentrations found in other environmental media to infer future or past aerosol exposures. this article presents an approach for linking environmental concentrations of bacillus. anthracis (b. anthracis) spores on walls, floors, ventilation system filters, and in human nasal passages with human health risk from expo ...201020626695
ratiometric fluorescent detection of an anthrax biomarker at molecular printboards. 201020629056
diversity of spore-forming bacteria in cattle manure, slaughterhouse waste and samples from biogas plants.as biowaste intended for biogas production can contain pathogenic micro-organisms, the recommended treatment is pasteurization at 70°c for 60min. this reduces pathogens such as salmonella spp., whereas spore-forming bacteria (bacillus spp. and clostridium spp.) survive. most spore-forming bacteria are harmless, but some can cause diseases such as blackleg, botulism and anthrax. in this study, the effect of the biogas process on bacillus spp. and clostridium spp. was investigated.201020629803
chicken cathelicidin-2-derived peptides with enhanced immunomodulatory and antibacterial activities against biological warfare agents.host defence peptides (hdps) are considered to be excellent candidates for the development of novel therapeutic agents. recently, it was demonstrated that the peptide c1-15, an n-terminal segment of chicken hdp cathelicidin-2, exhibits potent antibacterial activity while lacking cytotoxicity towards eukaryotic cells. in the present study, we report that c1-15 is active against bacteria such as bacillus anthracis and yersinia pestis that may potentially be used by bioterrorists. substitution of s ...201020630709
analysis of antibody responses to protective antigen-based anthrax vaccines through use of competitive assays.the licensed anthrax vaccine and many of the new anthrax vaccines being developed are based on protective antigen (pa), a nontoxic component of anthrax toxin. for this reason, an understanding of the immune response to pa vaccination is important. in this study, we examined the antibody response elicited by pa-based vaccines and identified the domains of pa that contribute to that response in humans as well as nonhuman primates (nhps) and rabbits, animal species that will be used to generate eff ...201020631338
the genome of a bacillus isolate causing anthrax in chimpanzees combines chromosomal properties of b. cereus with b. anthracis virulence plasmids.anthrax is a fatal disease caused by strains of bacillus anthracis. members of this monophyletic species are non motile and are all characterized by the presence of four prophages and a nonsense mutation in the plcr regulator gene. here we report the complete genome sequence of a bacillus strain isolated from a chimpanzee that had died with clinical symptoms of anthrax. unlike classic b. anthracis, this strain was motile and lacked the four prohages and the nonsense mutation. four replicons were ...201020634886
[progress in research on occupational anthrax]. 201020635707
anthrax lethal toxin activates the inflammasome in sensitive rat macrophages.anthrax lethal toxin (lt) is an important virulence factor for bacillus anthracis. in mice, lt lyses macrophages from certain inbred strains in less than 2h by activating the nlrp1b inflammasome and caspase-1, while macrophages from other strains remain resistant to the toxin's effects. we analyzed lt effects in toxin-sensitive and resistant rat macrophages to test if a similar pathway was involved in rat macrophage death. lt activates caspase-1 in rat macrophages from strains harboring lt-sensi ...201020638366
accidental selection and intentional restoration of sporulation-deficient bacillus anthracis mutants.we demonstrate the frequent accidental enrichment of spontaneous sporulation-deficient mutants of bacillus anthracis on solid medium and identify contributing factors. mutations in spo0a, encoding the master regulator of sporulation initiation, were found in 38 of 53 mutants. transductions using bacteriophage cp51 propagated on sporogenic bacteria allowed for the restoration of sporulation phenotypes.201020639373
integration and visualization of systems biology data in context of the genome.high-density tiling arrays and new sequencing technologies are generating rapidly increasing volumes of transcriptome and protein-dna interaction data. visualization and exploration of this data is critical to understanding the regulatory logic encoded in the genome by which the cell dynamically affects its physiology and interacts with its environment.201020642854
efficacy of daptomycin against bacillus anthracis in a murine model of anthrax spore inhalation.daptomycin demonstrated in vitro (mic(90), 4 μg/ml) and in vivo activities against bacillus anthracis. twice-daily treatment with a dose of 50 mg/kg of body weight was begun 24 h after challenge and continued for 14 or 21 days; results were compared to those for controls treated with phosphate-buffered saline or ciprofloxacin. day 43 survival rates were 6/10 mice for the 14-day and 9/10 mice for the 21-day treatment groups, compared to survival with ciprofloxacin: 8/10 and 9/10 mice, respectivel ...201020643899
biocidal properties of metal oxide nanoparticles and their halogen adducts.nanosized metal oxide halogen adducts possess high surface reactivities due to their unique surface morphologies. these adducts have been used as reactive materials against vegetative cells, such as escherichia coli as well as bacterial endospores, including bacillus subtilis and bacillus anthracis (delta sterne strain). here we report high biocidal activities against gram-positive bacteria, gram-negative bacteria, and endospores. the procedure consists of a membrane method. transmission electro ...201020644823
hand hygiene in the intensive care unit.healthcare-associated infections affect 1.4 million patients at any time worldwide, as estimated by the world health organization. in intensive care units, the burden of healthcare-associated infections is greatly increased, causing additional morbidity and mortality. multidrug-resistant pathogens are commonly involved in such infections and render effective treatment challenging. proper hand hygiene is the single most important, simplest, and least expensive means of preventing healthcare-assoc ...201020647787
deletion of the bacillus anthracis capb homologue in francisella tularensis subspecies tularensis generates an attenuated strain that protects mice against virulent tularaemia.as there is currently no licensed vaccine against francisella tularensis, the causative agent of tularaemia, the bacterium is an agent of concern as a potential bioweapon. although f. tularensis has a low infectious dose and high associated mortality, it possesses few classical virulence factors. an analysis of the f. tularensis subspecies tularensis genome sequence has revealed the presence of a region containing genes with low sequence homology to part of the capbcade operon of bacillus anthra ...201020651039
gastrointestinal anthrax after an animal-hide drumming event - new hampshire and massachusetts, 2009.on december 24, 2009, a woman aged 24 years from new hampshire was confirmed to have gastrointestinal anthrax on the basis of clinical findings and a bacillus anthracis blood culture isolate. her symptoms began on december 5. one day before symptom onset, she had participated in a drumming event at a community organization's building where animal-hide drums of multiple ages and origins were played. this report describes the case and subsequent investigation, which identified 84 persons potential ...201020651643
use of anthrax vaccine in the united states: recommendations of the advisory committee on immunization practices (acip), 2009.these recommendations from the advisory committee on immunization practices (acip) update the previous recommendations for anthrax vaccine adsorbed (ava) (cdc. use of anthrax vaccine in the united states: recommendations of the advisory committee on immunization practices [acip]. mmwr 2000;49:1-20; cdc. use of anthrax vaccine in response to terrorism: supplemental recommendations of the advisory committee on immunization practices [acip]. mmwr 2002;51:1024-6) and reflect the status of anthrax va ...201020651644
bacillus anthracis spore entry into epithelial cells is an actin-dependent process requiring c-src and pi3k.dissemination of bacillus anthracis from the respiratory mucosa is a critical step in the establishment of inhalational anthrax. recent in vitro and in vivo studies indicated that this organism was able to penetrate the lung epithelium by directly entering into epithelial cells of the lung; however the molecular details of b. anthracis breaching the epithelium were lacking. here, using a combination of pharmacological inhibitors, dominant negative mutants, and colocalization experiments, we demo ...201020652027
antxr2 and il-1r2 polymorphisms are not associated with ankylosing spondylitis in chinese han population.strong associations between the polymorphisms of anthrax toxin receptor 2 (antxr2) and interleukin-1 receptor 2 (il-1r2) and ankylosing spondylitis (as) were identified through genome-wide scan by australo-anglo-american spondyloarthritis consortium very recently. however, the data are restricted to caucasian patients in only the above report, and no replication study in other ethnic groups is published. our study addresses this relationship in chinese han population. a cohort of 200 as patients ...201020652271
comparison between active and passive surveillance within the network of epidemiological surveillance of animal diseases in chad.a comparative study between passive and active surveillance based on herd visits (villages) was conducted over a period of 24 months. it included 106 surveillance stations of the animal disease epidemiological surveillance network in chad distributed randomly into 52 stations of active surveillance and 54 stations of passive surveillance. nine diseases of various vaccination and expected prevalence status were monitored. the active surveillance stations carried out four herd visits monthly to lo ...201020655291
blockage of anthrax pa63 pore by a multicharged high-affinity toxin inhibitor.single channels of bacillus anthracis protective antigen, pa(63), were reconstituted into planar lipid membranes and their inhibition by cationic aminopropylthio-beta-cyclodextrin, amprbetacd, was studied. the design of the highly efficient inhibitor, the sevenfold symmetrical cyclodextrin molecule chemically modified to add seven positive charges, was guided by the symmetry and predominantly negative charge of the pa(63) pore. the protective action of this compound has been demonstrated earlier ...201020655841
the effects of preexisting immunity to influenza on responses to influenza vectors in mice.the use of viral vectors as vaccine candidates has shown promise against a number of pathogens. however, preexisting immunity to these vectors is a concern that must be addressed when deciding which viruses are suitable for use. a number of properties, including the existence of antigenically distinct subtypes, make influenza viruses attractive candidates for use as viral vectors. here, we evaluate the ability of influenza viral vectors containing inserts of foreign pathogens to elicit antibody ...201020656032
pathology of inhalational anthrax animal models.anthrax is a lethal disease caused by the bacterium bacillus anthracis. there are three principal forms of the disease in humans-cutaneous, gastrointestinal, and inhalational-depending on the route of exposure. of these, inhalational anthrax is the most dangerous; it is rapidly fatal; and it has been used as a deadly biological warfare agent in the last decade. suitable animal models of inhalational anthrax have been utilized to study pathogenesis of disease, investigate bacterial characteristic ...201020656900
identification of two aberrant transcripts derived from a hybridoma with amplification of functional immunoglobulin variable genes.murine monoclonal antibodies (mabs) are widely used but have limitations if administered in humans. the use of chimeric or humanized mabs can reduce immunogenicity. the first step in producing such mabs is to clone murine variable genes from a hybridoma, but it is possible to amplify both functional and aberrant variable genes, as they coexist in the hybridoma. during the development of a murine-human chimeric antibody, we have cloned from a hybridoma the functional heavy chain variable region ( ...201020657605
anthrax spore detection by a luminex assay based on monoclonal antibodies that recognize anthrose-containing oligosaccharides.the similarity of endospore surface antigens between bacteria of the bacillus cereus group complicates the development of selective antibody-based anthrax detection systems. the surface of b. anthracis endospores exposes a tetrasaccharide containing the monosaccharide anthrose. anti-tetrasaccharide monoclonal antibodies (mabs) and anti-anthrose-rhamnose disaccharide mabs were produced and tested for their fine specificities in a direct spore enzyme-linked immunosorbent assay (elisa) with inactiv ...201020660139
plague outbreaks in prairie dog populations explained by percolation thresholds of alternate host abundance.highly lethal pathogens (e.g., hantaviruses, hendra virus, anthrax, or plague) pose unique public-health problems, because they seem to periodically flare into outbreaks before disappearing into long quiescent phases. a key element to their possible control and eradication is being able to understand where they persist in the latent phase and how to identify the conditions that result in sporadic epidemics or epizootics. in american grasslands, plague, caused by yersinia pestis, exemplifies this ...201020660742
anthrax toxin-neutralizing antibody reconfigures the protective antigen heptamer into a supercomplex.the tripartite protein exotoxin secreted by bacillus anthracis, a major contributor to its virulence and anthrax pathogenesis, consists of binary complexes of the protective antigen (pa) heptamer (pa63h), produced by proteolytic cleavage of pa, together with either lethal factor or edema factor. the mouse monoclonal anti-pa antibody 1g3 was previously shown to be a potent antidote that shares f(c) domain dependency with the human monoclonal antibody mdx-1303 currently under clinical development. ...201020660775
an evaluation of commercial dna extraction kits for the isolation of bacterial spore dna from soil.to evaluate six commercial dna extraction kits for their ability to isolate pcr-quality dna from bacillus spores in various soil samples.201020666869
determination of the x-ray structure of the snake venom protein omwaprin by total chemical synthesis and racemic protein crystallography.the 50-residue snake venom protein l-omwaprin and its enantiomer d-omwaprin were prepared by total chemical synthesis. radial diffusion assays were performed against bacillus megaterium and bacillus anthracis; both l- and d-omwaprin showed antibacterial activity against b. megaterium. the native protein enantiomer, made of l-amino acids, failed to crystallize readily. however, when a racemic mixture containing equal amounts of l- and d-omwaprin was used, diffraction quality crystals were obtaine ...201020669184
evidence that histidine protonation of receptor-bound anthrax protective antigen is a trigger for pore formation.the protective antigen (pa) component of the anthrax toxin forms pores within the low ph environment of host endosomes through mechanisms that are poorly understood. it has been proposed that pore formation is dependent on histidine protonation. in previous work, we biosynthetically incorporated 2-fluorohistidine (2-fhis), an isosteric analogue of histidine with a significantly reduced pk(a) ( approximately 1), into pa and showed that the ph-dependent conversion from the soluble prepore to a por ...201020672855
a novel two-component tobacco mosaic virus-based vector system for high-level expression of multiple therapeutic proteins including a human monoclonal antibody in plants.expression of multiple therapeutic proteins from tobacco mosaic virus (tmv)-based vectors was not successful when plants were coinoculated with a mixture of two tmv vectors engineered to express two foreign genes individually. here, we have engineered and developed a defective rna (drna)-based tmv vector (drt-v) that utilizes two components of the same virus, with the drna component depending on the helper virus for replication. agrobacterium-mediated coinoculation of nicotiana benthamiana plant ...201020673747
characterization of the enzymes encoded by the anthrose biosynthetic operon of bacillus anthracis.bacillus anthracis spores, the etiological agents of anthrax, possess a loosely fitting outer layer called the exosporium that is composed of a basal layer and an external hairlike nap. the filaments of the nap are formed by trimers of the collagenlike glycoprotein bcla. multiple pentasaccharide and trisaccharide side chains are o linked to bcla. the nonreducing terminal residue of the pentasaccharide side chain is the unusual sugar anthrose. a plausible biosynthetic pathway for anthrose biosynt ...201020675481
phenotype based functional gene screening using retrovirus-mediated gene trapping in quasi-haploid raw 264.7 cells.in vitro random mutagenesis, followed by phenotype screening, provides a rapid and convenient tool for identifying novel genes involved in the phenotype of interest. however, the forward mutagenic approach in mammalian somatic cells is seriously limited by the diploidic nature of the genome. to overcome this impediment, we developed a method that allows functional screening for both haploid insufficient and sufficient genes involved in the phenotype of interest, utilizing a retrovirus gene trap ...201020676994
[treatment of the patient with anthrax complicated with gastric bleeding]. 201020524239
[henry toussaint and louis pasteur. rivalry over a vaccine].henry toussaint (1847-1890) is a veterinary who studied in veterinary school of lyon with his great master auguste chauveau the famous physiologist. this place is the first school founded in europe at the end of the xviiith century and has opened a way of thinking. his carrer brilliant and rich begins first in lyon and then when he is named professor of anatomy and physiology at the veterinary school of toulouse. doctor of science and doctor of medecine toussaint applies "the experimental method ...201020527335
biosynthesis of a new udp-sugar, udp-2-acetamido-2-deoxyxylose, in the human pathogen bacillus cereus subspecies cytotoxis nvh 391-98.we have identified an operon and characterized the functions of two genes from the severe food-poisoning bacterium, bacillus cereus subsp. cytotoxis nvh 391-98, that are involved in the synthesis of a unique udp-sugar, udp-2-acetamido-2-deoxyxylose (udp-n-acetyl-xylosamine, udp-xylnac). uglcnacdh encodes a udp-n-acetyl-glucosamine 6-dehydrogenase, converting udp-n-acetylglucosamine (udp-glcnac) to udp-n-acetyl-glucosaminuronic acid (udp-glcnaca). the second gene in the operon, uxnacs, encodes a ...201020529859
select human anthrax protective antigen epitope-specific antibodies provide protection from lethal toxin challenge.bacillus anthracis remains a serious bioterrorism concern, and the currently licensed vaccine remains an incomplete solution for population protection from inhalation anthrax and has been associated with concerns regarding efficacy and safety. thus, understanding how to generate long-lasting protective immunity with reduced immunizations or provide protection through postexposure immunotherapeutics are long-sought goals. through evaluation of a large military cohort, we characterized the levels ...201020533877
use of allostery to identify inhibitors of calmodulin-induced activation of bacillus anthracis edema factor.allostery plays a key role in the regulation of the activity and function of many biomolecules. and although many ligands act through allostery, no systematic use is made of it in drug design strategies. here we describe a procedure for identifying the regions of a protein that can be used to control its activity through allostery. this procedure is based on the construction of a plausible conformational path, which describes protein transition between known active and inactive conformations. th ...201020534570
subunit and small-molecule interaction of ribonucleotide reductases via surface plasmon resonance biosensor analyses.ribonucleotide reductase (rnr) synthesizes deoxyribonucleotides for dna replication and repair and is controlled by sophisticated allosteric regulation involving differential affinity of nucleotides for regulatory sites. we have developed a robust and sensitive method for coupling biotinylated rnrs to surface plasmon resonance streptavidin biosensor chips via a 30.5 a linker. in comprehensive studies on three rnrs effector nucleotides strengthened holoenzyme interactions, whereas substrate had n ...201020534631
activation of nf-κb pathway and tnf-α are involved in the cytotoxicity of anthrax lethal toxin in bovine bomac macrophages.anthrax lethal toxin (letx) is an important virulence factor of bacillus anthracis and causes illness and lethality for both animals and humans. because species demonstrate varied sensitivity to anthrax intoxication, we investigated signaling pathways involved in anthrax letx cytotoxicity using a bovine macrophage cell line (bomac). we found that bovine macrophages are sensitive to letx as displayed by a concentration-dependent increase in cell death. letx induced the degradation of i-κb and inc ...201020537817
validation of a nylon-flocked-swab protocol for efficient recovery of bacterial spores from smooth and rough surfaces.in order to meet planetary-protection requirements, culturable bacterial spore loads are measured representatively for the total microbial contamination of spacecraft. however, the national aeronautics and space administration's (nasa's) cotton swab protocols for spore load determination have not changed for decades. to determine whether a more efficient alternative was available, a novel swab was evaluated for recovery of different bacillus atrophaeus spore concentrations on stainless steel and ...201020543054
a novel spore protein, exsm, regulates formation of the exosporium in bacillus cereus and bacillus anthracis and affects spore size and shape.bacillus cereus spores are assembled with a series of concentric layers that protect them from a wide range of environmental stresses. the outermost layer, or exosporium, is a bag-like structure that interacts with the environment and is composed of more than 20 proteins and glycoproteins. here, we identified a new spore protein, exsm, from a beta-mercaptoethanol extract of b. cereus atcc 4342 spores. subcellular localization of an exsm-green fluorescent protein (gfp) protein revealed a dynamic ...201020543075
law in the time of anthrax: biosecurity lessons from the united states.in 2009, under the national health security act 2007 (cth), the australian government began introducing biosecurity regulations for laboratory research and other work involving certain pathogenic micro-organisms. the security-sensitive biological agents (ssba) scheme is virtually unprecedented in australia but is similar to the biological select agents and toxins (bsats) scheme which has existed in the united states since the mid-1990s. this article examines recent united states experience in us ...201020552938
detection of low numbers of bacillus anthracis spores in three soils using five commercial dna extraction methods with and without an enrichment step.to (i) compare the limits of detection of bacillus anthracis spores in three soils (one florida, one texas, and one a commercial garden product) by pcr using dna extracted with five commercial extraction kits and (ii) examine if removing organic acids or adding an enrichment step utilizing a growth medium will improve the detection limits.201020553343
key roles of dendritic cells in lung infection and improving anthrax vaccines.lung immune responses control pathogens while avoiding detrimental inflammation. the dynamics of lung homeostasis are not fully understood. primary antimicrobial defenses are orchestrated by epithelial cells (ecs), interacting in close association with dendritic cells (dcs) and other innate immune cells. however, microbes, such as bacillus anthracis use host cellular machinery, including dc-migratory capacity to reach the draining lymph nodes where they germinate and produce toxins that disrupt ...201020554248
membrane chromatography: protein purification from e. coli lysate using newly designed and commercial anion-exchange stationary phases.this contribution describes the purification of anthrax protective antigen (pa) protein from escherichia coli lysate using bind-and-elute chromatography with newly designed weak anion-exchange membranes. protein separation performance of the new aex membrane adsorber was compared with the commercial sartobind d membrane adsorber and hitrap deae ff resin column under preparative scale conditions. dynamic protein binding capacities of all three stationary phases were determined using breakthrough ...201020554285
genome-wide single nucleotide polymorphism typing method for identification of bacillus anthracis species and strains among b. cereus group species.as an issue of biosecurity, species-specific genetic markers have been well characterized. however, bacillus anthracis strain-specific information is currently not sufficient for traceability to identify the origin of the strain. by using genome-wide screening using short read mapping, we identified strain-specific single nucleotide polymorphisms (snps) among b. anthracis strains including japanese isolates, and we further developed a simplified 80-tag snp typing method for the primary investiga ...201020554827
oligochlorophens are potent inhibitors of bacillus anthracis.bacterial cytoskeletal proteins are an emerging set of targets for antibiotic development. this paper describes oligochlorophen analogs based on the monomer 4-chloro-2,6-dimethylphenol as antimicrobial agents against bacillus anthracis. the most potent analogs have a mic of 160 to 320 nm against b. anthracis and may target the cytoskeletal protein ftsz. b. anthracis develops resistance to the oligochlorophens at a rate of 4.34 x 10(-10) per generation, which is approximately 10-fold lower than t ...201020566769
adverse events following smallpox vaccination with acam2000 in a military population.generalized vaccinia and benign exanthems are 2 adverse events that have been associated with the smallpox vaccination. accurate incidence and prevalence rates of each are not readily available, but these events are thought to be uncommon. to our knowledge, this is the first case series to provide clinical as well as pathologic descriptions of multiple papulovesicular eruptions occurring after receiving the second-generation smallpox vaccine, acam2000 (acambis, canton, massachusetts), among a va ...201020566929
a novel pharmacophore model for the design of anthrax lethal factor inhibitors.this study aims at the identification of novel structural features on the surface of the zn-dependent metalloprotease lethal factor (lf) from anthrax onto which to design novel and selective inhibitors. we report that by targeting an unexplored region of lf that exhibits ligand-induced conformational changes, we could obtain inhibitors with at least 30-fold lf selectivity compared to two other most related human metalloproteases, mmp-2 and mmp-9. based on these results, we propose a novel pharma ...201020572812
essentiality and functional analysis of type i and type iii pantothenate kinases of mycobacterium tuberculosis.pantothenate kinase, an essential enzyme in bacteria and eukaryotes, is involved in catalysing the first step of conversion of pantothenate to coenzyme a (coa). three isoforms (type i, ii and iii) of this enzyme have been reported from various organisms, which can be differentiated from each other on the basis of their biochemical and structural characteristics. though most bacteria carry only one of the isoforms of pantothenate kinases, some of them possess two isoforms. the physiological relev ...201020576686
complexes of bacterial nicotinate mononucleotide adenylyltransferase with inhibitors: implication for structure-based drug design and improvement.bacterial nicotinate mononucleotide adenylyltransferase encoded by the essential gene nadd plays a central role in the synthesis of the redox cofactor nad(+). the nadd enzyme is conserved in the majority of bacterial species and has been recognized as a novel target for developing new and potentially broad-spectrum antibacterial therapeutics. here we report the crystal structures of bacillus anthracis nadd in complex with three nadd inhibitors, including two analogues synthesized in the present ...201020578699
mucosal adjuvant activity of cholera toxin requires th17 cells and protects against inhalation anthrax.cholera toxin (ct) elicits a mucosal immune response in mice when used as a vaccine adjuvant. the mechanisms by which ct exerts its adjuvant effects are incompletely understood. we show that protection against inhalation anthrax by an irradiated spore vaccine depends on ct-mediated induction of il-17-producing cd4 th17 cells. furthermore, il-17 is involved in the induction of serum and mucosal antibody responses by ct. th17 cells induced by ct have a unique cytokine profile compared with those i ...201020479237
disulfide bonds in the ectodomain of anthrax toxin receptor 2 are required for the receptor-bound protective-antigen pore to function.cell-surface receptors play essential roles in anthrax toxin action by providing the toxin with a high-affinity anchor and self-assembly site on the plasma membrane, mediating the toxin entry into cells through endocytosis, and shifting the ph threshold for prepore-to-pore conversion of anthrax toxin protective antigen (pa) to a more acidic ph, thereby inhibiting premature pore formation. each of the two known anthrax toxin receptors, antxr1 and antxr2, has an ectodomain comprised of an n-termin ...201020479891
b cell development in galt: role of bacterial superantigen-like molecules.intestinal bacteria drive the formation of lymphoid tissues, and in rabbit, bacteria also promote development of the preimmune ab repertoire and positive selection of b cells in galt. previous studies indicated that bacillus subtilis promotes b cell follicle formation in galt, and we investigated the mechanism by which b. subtilis stimulates b cells. we found that spores of b. subtilis and other bacillus species, including bacillus anthracis, bound rabbit igm through an unconventional, superanti ...201020483765
genetic analysis of petrobactin transport in bacillus anthracis.iron acquisition mechanisms play an important role in the pathogenesis of many infectious microbes. in bacillus anthracis, the siderophore petrobactin is required for both growth in iron-depleted conditions and for full virulence of the bacterium. here we demonstrate the roles of two putative petrobactin binding proteins fatb and fpua (encoded by gbaa5330 and gbaa4766 respectively) in b. anthracis iron acquisition and pathogenesis. markerless deletion mutants were created using allelic exchange. ...201020487286
the sortase a enzyme that attaches proteins to the cell wall of bacillus anthracis contains an unusual active site architecture.the pathogen bacillus anthracis uses the sortase a (srta) enzyme to anchor proteins to its cell wall envelope during vegetative growth. to gain insight into the mechanism of protein attachment to the cell wall in b. anthracis we investigated the structure, backbone dynamics, and function of srta. the nmr structure of srta has been determined with a backbone coordinate precision of 0.40 +/- 0.07 a. srta possesses several novel features not previously observed in sortase enzymes including the pres ...201020489200
lmbe proteins from bacillus cereus are de-n-acetylases with broad substrate specificity and are highly similar to proteins in bacillus anthracis.the genomes of bacillus cereus and its closest relative bacillus anthracis each contain two lmbe protein family homologs: bc1534 (ba1557) and bc3461 (ba3524). only a few members of this family have been biochemically characterized including n-acetylglucosaminylphosphatidyl inositol (glcnac-pi), 1-d-myo-inosityl-2-acetamido-2-deoxy-alpha-d-glucopyranoside (glcnac-ins), n,n'-diacetylchitobiose (glcnac(2)) and lipoglycopeptide antibiotic de-n-acetylases. all these enzymes share a common feature in ...201020491912
recent advances in rapid and ultrasensitive biosensors for infectious agents: lesson from bacillus anthracis diagnostic sensors.here, we review the cumulative efforts to develop rapid and ultrasensitive diagnostic systems, especially for the infectious agent, bacillus anthracis, as a model system. this minireview focuses on demonstrating the features of various probes for target molecule detection and recent methods of signal generation within the biosensors. also, we discuss the possibility of using peptides as next-generation probe molecules.201020498871
environmental factors determining the epidemiology and population genetic structure of the bacillus cereus group in the field.bacillus thuringiensis (bt) and its insecticidal toxins are widely exploited in microbial biopesticides and genetically modified crops. its population biology is, however, poorly understood. important issues for the safe, sustainable exploitation of bt include understanding how selection maintains expression of insecticidal toxins in nature, whether entomopathogenic bt is ecologically distinct from related human pathogens in the bacillus cereus group, and how the use of microbial pesticides alte ...201020502683
susceptibility to anthrax lethal toxin-induced rat death is controlled by a single chromosome 10 locus that includes rnlrp1.anthrax lethal toxin (lt) is a bipartite protease-containing toxin and a key virulence determinant of bacillus anthracis. in mice, lt causes the rapid lysis of macrophages isolated from certain inbred strains, but the correlation between murine macrophage sensitivity and mouse strain susceptibility to toxin challenge is poor. in rats, lt induces a rapid death in as little as 37 minutes through unknown mechanisms. we used a recombinant inbred (ri) rat panel of 19 strains generated from lt-sensiti ...201020502689
induction of neutralizing antibody responses to anthrax protective antigen by using influenza virus vectors: implications for disparate immune system priming pathways.viral vectors based on influenza virus, rabies virus (rv), and vaccinia virus (vv) were used to express large polypeptide segments derived from the bacillus anthracis protective antigen (pa). for the infectious influenza virus vector and recombinant vv constructs, the receptor binding domain (rbd or domain 4) or the lethal and edema factor binding domain (lef or domain 1') were engineered into functional chimeric hemagglutinin (ha) glycoproteins. in the case of the rv vector, the viral glycoprot ...201020504926
hydrophobic properties and extraction of bacillus anthracis spores from liquid foods.the objectives of this study were to characterize the hydrophobic properties of three strains of bacillus anthracis using the microbial adherence to hydrocarbons (math) assay and determine the recovery of spores by hexadecane extraction from water, milk and orange juice using a modified version of this assay. in water mixtures, the hydrophobicity of b. anthracis spores ranged from 5 to 80% as the concentration of hexadecane and the mixing time increased. two of the three strains showed significa ...201020510785
multigeneration cross contamination of mail with bacillus species spores by tumbling.in 2001, envelopes loaded with bacillus anthracis spores were mailed to senators daschle and leahy as well as to the new york post and nbc news buildings. additional letters may have been mailed to other news agencies because there was confirmed anthrax infection of employees at these locations. these events heightened the awareness of the lack of understanding of the mechanism(s) by which objects contaminated with a biological agent might spread disease. this understanding is crucial for the es ...201020511424
communicable diseases report, nsw, january and february 2010. 201020513312
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