| rapid assembly of a multimeric membrane protein pore. | we have observed the assembly of the staphylococcal pore-forming toxin α-hemolysin using single-molecule fluorescence imaging. surprisingly, assembly from the monomer to the complete heptamer is extremely rapid, occurring in <5 ms. no lower order oligomeric intermediates are detected. monte carlo simulation of our experiment shows that assembly is diffusion limited, and pore formation is dependent on the stability of intermediate species. there are close similarities between bacterial pore-formi ... | 2011 | 22261056 |
| nanohole-based spr instruments with improved spectral resolution quantify a broad range of antibody-ligand binding kinetics. | we demonstrate an affordable low-noise spr instrument based on extraordinary optical transmission (eot) in metallic nanohole arrays and quantify a broad range of antibody-ligand binding kinetics with equilibrium dissociation constants ranging from 200 pm to 40 nm. this nanohole-based spr instrument is straightforward to construct, align, and operate, since it is built around a standard microscope and a portable fiber-optic spectrometer. the measured refractive index resolution of this platform i ... | 2012 | 22235895 |
| structural studies on antd: an n-acyltransferase involved in the biosynthesis of d-anthrose. | the unusual dideoxysugar d-anthrose has been identified as an important component in the endospores of such infectious agents as bacillus anthracis and bacillus cereus. specifically, it is the terminal sugar on the bacterium's exosporium, and it provides a point of interaction between the spore and the host. the biosynthesis of d-anthrose involves numerous steps starting from α-d-glucose-1-phosphate. here we present a combined structural and functional investigation of antd from b. cereus. this ... | 2012 | 22220494 |
| curing of plasmid pxo1 from bacillus anthracis using plasmid incompatibility. | the large plasmid pxo1 encoding the anthrax toxin is important for the virulence of bacillus anthracis. it is essential to cure pxo1 from b. anthracis to evaluate its role in the pathogenesis of anthrax infection. because conventional methods for curing plasmids (e.g., curing agents or growth at elevated temperatures) can induce mutations in the host chromosomal dna, we developed a specific and reliable method to eliminate pxo1 from b. anthracis using plasmid incompatibility. three putative repl ... | 2012 | 22253811 |
| the dark sides of capillary morphogenesis gene 2. | capillary morphogenesis gene 2 (cmg2) is a type i membrane protein involved in the homeostasis of the extracellular matrix. while it shares interesting similarities with integrins, its exact molecular role is unknown. the interest and knowledge about cmg2 largely stems from the fact that it is involved in two diseases, one infectious and one genetic. cmg2 is the main receptor of the anthrax toxin, and knocking out this gene in mice renders them insensitive to infection with bacillus anthracis sp ... | 2011 | 22215446 |
| [efficacy of enterocin s760 in treatment of mice with anthrax infection due to bacillus anthracis m-71]. | the therapeutic efficacy of enterocin s760, a broad spectrum antimicrobial peptide produced by enterococcus faecium lwp760 was tested on mice infected with bacillus anthracis m-71 to induce anthrax (second tsenkovsky's vaccine). intraperitoneal four-, two- or one-fold administration of the peptide in a dose of 25 mg/kg for 10 days for prophylactic (1 hour after the contamination) and therapeutic (24 hours after the contamination) purposes prevented or cured the infection in 90-100% of the mice v ... | 2011 | 22586898 |
| mhc class ii and non-mhc class ii genes differentially influence humoral immunity to bacillus anthracis lethal factor and protective antigen. | anthrax lethal toxin consists of protective antigen (pa) and lethal factor (lf), and current vaccination strategies focus on eliciting antibodies to pa. in human vaccination, the response to pa can vary greatly, and the response is often directed toward non-neutralizing epitopes. variable vaccine responses have been shown to be due in part to genetic differences in individuals, with both mhc class ii and other genes playing roles. here, we investigated the relative contribution of mhc class ii v ... | 2012 | 23342680 |
| the receptors that mediate the direct lethality of anthrax toxin. | tumor endothelium marker-8 (tem8) and capillary morphogenesis protein-2 (cmg2) are the two well-characterized anthrax toxin receptors, each containing a von willebrand factor a (vwa) domain responsible for anthrax protective antigen (pa) binding. recently, a cell-based analysis was used to implicate another vwa domain-containing protein, integrin β1 as a third anthrax toxin receptor. to explore whether proteins other than tem8 and cmg2 function as anthrax toxin receptors in vivo, we challenged m ... | 2012 | 23271637 |
| quantitative assessment of anthrax vaccine immunogenicity using the dried blood spot matrix. | the collection, processing and transportation to a testing laboratory of large numbers of clinical samples during an emergency response situation present significant cost and logistical issues. blood and serum are common clinical samples for diagnosis of disease. serum preparation requires significant on-site equipment and facilities for immediate processing and cold storage, and significant costs for cold-chain transport to testing facilities. the dried blood spot (dbs) matrix offers an alterna ... | 2012 | 23266055 |
| soft-x-ray-enhanced electrostatic precipitation for protection against inhalable allergens, ultrafine particles, and microbial infections. | protection of the human lung from infectious agents, allergens, and ultrafine particles is difficult with current technologies. high-efficiency particulate air (hepa) filters remove airborne particles of >0.3 μm with 99.97% efficiency, but they are expensive to maintain. electrostatic precipitation has been used as an inexpensive approach to remove large particles from airflows, but it has a collection efficiency minimum in the submicrometer size range, allowing for a penetration window for some ... | 2012 | 23263945 |
| recombinant groel enhances protective antigen-mediated protection against bacillus anthracis spore challenge. | the fatal inhalation infection caused by bacillus anthracis results from a complex pathogenic cycle involving release of toxins by bacteria that germinate from spores. currently available vaccines against anthrax consist of protective antigen (pa), one of the anthrax toxin components. however, these pa-based vaccines are only partially protective against spore challenge in mice. this shows that exclusive elicitation of high anti-pa titer does not directly correlate with protection. here, we demo ... | 2012 | 23263010 |
| investigation of an outbreak of cutaneous anthrax in banlu village, lianyungang, china, 2012. | after notification of a suspected case of anthrax following the slaughtering of a sick cow in banlu village, an area that has not had any anthrax cases for decades, we aimed to confirm the outbreak, determine the transmission mechanism and implement control measures. | 2012 | 23908932 |
| anthrax and the taiga. | | 2012 | 23543935 |
| zoonotic infections among employees from great smoky mountains and rocky mountain national parks, 2008-2009. | u.s. national park service employees may have prolonged exposure to wildlife and arthropods, placing them at increased risk of infection with endemic zoonoses. to evaluate possible zoonotic risks present at both great smoky mountains (grsm) and rocky mountain (romo) national parks, we assessed park employees for baseline seroprevalence to specific zoonotic pathogens, followed by evaluation of incident infections over a 1-year study period. park personnel showed evidence of prior infection with a ... | 2012 | 22835153 |
| bacillus anthracis inosine 5'-monophosphate dehydrogenase in action: the first bacterial series of structures of phosphate ion-, substrate-, and product-bound complexes. | inosine 5'-monophosphate dehydrogenase (impdh) catalyzes the first unique step of the gmp branch of the purine nucleotide biosynthetic pathway. this enzyme is found in organisms of all three kingdoms. impdh inhibitors have broad clinical applications in cancer treatment, as antiviral drugs and as immunosuppressants, and have also displayed antibiotic activity. we have determined three crystal structures of bacillus anthracis impdh, in a phosphate ion-bound (termed "apo") form and in complex with ... | 2012 | 22788966 |
| climate change and zoonotic infections in the russian arctic. | climate change in the russian arctic is more pronounced than in any other part of the country. between 1955 and 2000, the annual average air temperature in the russian north increased by 1.2°c. during the same period, the mean temperature of upper layer of permafrost increased by 3°c. climate change in russian arctic increases the risks of the emergence of zoonotic infectious diseases. this review presents data on morbidity rates among people, domestic animals and wildlife in the russian arctic, ... | 2012 | 22868189 |
| climate change and infectious diseases in the arctic: establishment of a circumpolar working group. | the arctic, even more so than other parts of the world, has warmed substantially over the past few decades. temperature and humidity influence the rate of development, survival and reproduction of pathogens and thus the incidence and prevalence of many infectious diseases. higher temperatures may also allow infected host species to survive winters in larger numbers, increase the population size and expand their habitat range. the impact of these changes on human disease in the arctic has not bee ... | 2014 | 25317383 |
| crossing of the epithelial barriers by bacillus anthracis: the known and the unknown. | anthrax, caused by bacillus anthracis, a gram-positive spore-forming bacterium, is initiated by the entry of spores into the host body. there are three types of human infection: cutaneous, inhalational, and gastrointestinal. for each form, b. anthracis spores need to cross the cutaneous, respiratory or digestive epithelial barriers, respectively, as a first obligate step to establish infection. anthrax is a toxi-infection: an association of toxemia and rapidly spreading infection progressing to ... | 2015 | 26500645 |
| hfqs in bacillus anthracis: role of protein sequence variation in the structure and function of proteins in the hfq family. | hfq proteins in gram-negative bacteria play important roles in bacterial physiology and virulence, mediated by binding of the hfq hexamer to small rnas and/or mrnas to post-transcriptionally regulate gene expression. however, the physiological role of hfqs in gram-positive bacteria is less clear. bacillus anthracis, the causative agent of anthrax, uniquely expresses three distinct hfq proteins, two from the chromosome (hfq1, hfq2) and one from its pxo1 virulence plasmid (hfq3). the protein seque ... | 2015 | 26271475 |
| identification, functional characterization and regulon prediction of a novel two component system comprising bas0540-bas0541 of bacillus anthracis. | two component systems (tcss) can be envisaged as complex molecular devices that help the bacteria to sense its environment and respond aptly. 41 tcss are predicted in bacillus anthracis, a potential bioterrorism agent, of which only four have been studied so far. thus, the intricate signaling network contributed by tcss remains largely unmapped in b. anthracis and needs comprehensive exploration. in this study, we functionally characterized one such system composed of bas0540 (response regulator ... | 2016 | 27392063 |
| biosensors for whole-cell bacterial detection. | bacterial pathogens are important targets for detection and identification in medicine, food safety, public health, and security. bacterial infection is a common cause of morbidity and mortality worldwide. in spite of the availability of antibiotics, these infections are often misdiagnosed or there is an unacceptable delay in diagnosis. current methods of bacterial detection rely upon laboratory-based techniques such as cell culture, microscopic analysis, and biochemical assays. these procedures ... | 2014 | 24982325 |
| eco-genetic structure of bacillus cereus sensu lato populations from different environments in northeastern poland. | the bacillus cereus group, which includes entomopathogens and etiologic agents of foodborne illness or anthrax, persists in various environments. the basis of their ecological diversification remains largely undescribed. here we present the genetic structure and phylogeny of 273 soil b. cereus s.l. isolates from diverse habitats in northeastern poland, with samplings acquired from the last european natural forest (białowieża national park), the largest marshes in europe (biebrza national park), ... | 2013 | 24312460 |
| evaluation of a microfluidic chip system for preparation of bacterial dna from swabs, air, and surface water samples. | the detection of bacterial pathogens from complex sample matrices by pcr requires efficient dna extraction. in this study, a protocol for extraction and purification of dna from swabs, air, and water samples using a microfluidic chip system was established. the optimized protocol includes a combination of thermal, chemical and enzymatic lysis followed by chip-based dna purification using magnetic particles. the procedure was tested using gram-positive bacillus thuringiensis berliner var. kurstak ... | 2016 | 27520284 |
| zoonoses: a potential obstacle to the growing wildlife industry of namibia. | zoonoses, which account for approximately 75% of emerging human infectious diseases worldwide, pose a re-emerging threat to public health. with an ever-increasing interrelationship between humans, livestock and wildlife species, the threat to human health will rise to unprecedented levels. wildlife species contribute to the majority of emerging diseases; therefore, there is an urgent need to define control systems of zoonoses of wildlife origin but very little information exists. in this review, ... | 2012 | 23077724 |
| a new generation microarray for the simultaneous detection and identification of yersinia pestis and bacillus anthracis in food. | the use of microarrays as a multiple analytic system has generated increased interest and provided a powerful analytical tool for the simultaneous detection of pathogens in a single experiment. a wide array of applications for this technology has been reported. a low density oligonucleotide microarray was generated from the genetic sequences of y. pestis and b. anthracis and used to fabricate a microarray chip. the new generation chip, consisting of 2,240 spots in 4 quadrants with the capability ... | 2012 | 23125935 |
| insights from genomic comparisons of genetically monomorphic bacterial pathogens. | some of the most deadly bacterial diseases, including leprosy, anthrax and plague, are caused by bacterial lineages with extremely low levels of genetic diversity, the so-called 'genetically monomorphic bacteria'. it has only become possible to analyse the population genetics of such bacteria since the recent advent of high-throughput comparative genomics. the genomes of genetically monomorphic lineages contain very few polymorphic sites, which often reflect unambiguous clonal genealogies. some ... | 2012 | 22312053 |
| crystal structures of putative phosphoglycerate kinases from b. anthracis and c. jejuni. | phosphoglycerate kinase (pgk) is indispensable during glycolysis for anaerobic glucose degradation and energy generation. here we present comprehensive structure analysis of two putative pgks from bacillus anthracis str. sterne and campylobacter jejuni in the context of their structural homologs. they are the first pgks from pathogenic bacteria reported in the protein data bank. the crystal structure of pgk from bacillus anthracis str. sterne (bapgk) has been determined at 1.68 å while the struc ... | 2012 | 22403005 |
| systemic use of fluoroquinolone in children. | fluoroquinolones are an important class of antibiotics that are widely used in adult patients because of their broad spectrum of activity, good tissue penetration, and oral bioavailability. however, fluoroquinolone use in children is limited because juvenile animals developed arthropathy in previous experiments on fluoroquinolone use. indications for fluoroquinolone use in patients younger than 18 years, as stated by the u.s. food and drug administration, include treatment of complicated urinary ... | 2013 | 23741232 |
| inactivation of bacterial biothreat agents in water, a review. | water supplies and water distribution systems have been identified as potential targets for contamination by bacterial biothreat agents. since the 2001 bacillus anthracis bioterrorist attacks, additional efforts have been aimed at research to characterize biothreat organisms in regards to their susceptibility to disinfectants and technologies currently in use for potable water. here, we present a review of research relevant to disinfection of bacteria with the potential to pose a severe threat t ... | 2014 | 25473971 |
| structure of the ldcb ld-carboxypeptidase reveals the molecular basis of peptidoglycan recognition. | peptidoglycan surrounds the bacterial cytoplasmic membrane to protect the cell against osmolysis. the biosynthesis of peptidoglycan, made of glycan strands crosslinked by short peptides, is the target of antibiotics like β-lactams and glycopeptides. nascent peptidoglycan contains pentapeptides that are trimmed by carboxypeptidases to tetra- and tripeptides. the well-characterized dd-carboxypeptidases hydrolyze the terminal d-alanine from the stem pentapeptide to produce a tetrapeptide. however, ... | 2014 | 24909784 |
| cytolethal distending toxin b as a cell-killing component of tumor-targeted anthrax toxin fusion proteins. | cytolethal distending toxin (cdt) is produced by gram-negative bacteria of several species. it is composed of three subunits, cdta, cdtb, and cdtc, with cdtb being the catalytic subunit. we fused cdtb from haemophilus ducreyi to the n-terminal 255 amino acids of bacillus anthracis toxin lethal factor (lfn) to design a novel, potentially potent antitumor drug. as a result of this fusion, cdtb was transported into the cytosol of targeted cells via the efficient delivery mechanism of anthrax toxin. ... | 2014 | 24434511 |
| bacterial exotoxins and the inflammasome. | the inflammasomes are intracellular protein complexes that play an important role in innate immune sensing. activation of inflammasomes leads to activation of caspase-1 and maturation and secretion of the pro-inflammatory cytokines interleukin (il)-1β and il-18. in certain myeloid cells, this activation can also lead to an inflammatory cell death (pyroptosis). inflammasome sensor proteins have evolved to detect a range of microbial ligands and bacterial exotoxins either through direct interactio ... | 2015 | 26617605 |
| a novel cofactor-binding mode in bacterial imp dehydrogenases explains inhibitor selectivity. | the steadily rising frequency of emerging diseases and antibiotic resistance creates an urgent need for new drugs and targets. inosine 5'-monophosphate dehydrogenase (imp dehydrogenase or impdh) is a promising target for the development of new antimicrobial agents. impdh catalyzes the oxidation of imp to xmp with the concomitant reduction of nad(+), which is the pivotal step in the biosynthesis of guanine nucleotides. potent inhibitors of bacterial impdhs have been identified that bind in a stru ... | 2015 | 25572472 |
| geospatial resolution of human and bacterial diversity with city-scale metagenomics. | the panoply of microorganisms and other species present in our environment influence human health and disease, especially in cities, but have not been profiled with metagenomics at a city-wide scale. we sequenced dna from surfaces across the entire new york city (nyc) subway system, the gowanus canal, and public parks. nearly half of the dna (48%) does not match any known organism; identified organisms spanned 1,688 bacterial, viral, archaeal, and eukaryotic taxa, which were enriched for harmles ... | 2015 | 26594662 |
| comprehensive laboratory evaluation of a highly specific lateral flow assay for the presumptive identification of bacillus anthracis spores in suspicious white powders and environmental samples. | we conducted a comprehensive, multiphase laboratory evaluation of the anthrax biothreat alert(®) test strip, a lateral flow immunoassay (lfa) for the rapid detection of bacillus anthracis spores. the study, conducted at 2 sites, evaluated this assay for the detection of spores from the ames and sterne strains of b. anthracis, as well as those from an additional 22 strains. phylogenetic near neighbors, environmental background organisms, white powders, and environmental samples were also tested. ... | 2016 | 27661796 |
| anthracimycin, a potent anthrax antibiotic from a marine-derived actinomycete. | licensed to kill: a new antibiotic, anthracimycin (see scheme), produced by a marine-derived actinomycete in saline culture, shows significant activity toward bacillus anthracis, the bacterial pathogen responsible for anthrax infections. chlorination of anthracimycin gives a dichloro derivative that retains activity against gram-positive bacteria, such as anthrax, but also shows activity against selected gram-negative bacteria. | 2013 | 23776159 |
| bacillus anthracis factors for phagosomal escape. | the mechanism of phagosome escape by intracellular pathogens is an important step in the infectious cycle. during the establishment of anthrax, bacillus anthracis undergoes a transient intracellular phase in which spores are engulfed by local phagocytes. spores germinate inside phagosomes and grow to vegetative bacilli, which emerge from their resident intracellular compartments, replicate and eventually exit from the plasma membrane. during germination, b. anthracis secretes multiple factors th ... | 2012 | 22852067 |
| rapid and high-throughput detection of highly pathogenic bacteria by ibis plex-id technology. | in this manuscript, we describe the identification of highly pathogenic bacteria using an assay coupling biothreat group-specific pcr with electrospray ionization mass spectrometry (pcr/esi-ms) run on an ibis plex-id high-throughput platform. the biothreat cluster assay identifies most of the potential bioterrorism-relevant microorganisms including bacillus anthracis, francisella tularensis, yersinia pestis, burkholderia mallei and pseudomallei, brucella species, and coxiella burnetii. dna from ... | 2012 | 22768173 |
| comparison of two suspension arrays for simultaneous detection of five biothreat bacterial in powder samples. | we have developed novel bio-plex assays for simultaneous detection of bacillus anthracis, yersinia pestis, brucella spp., francisella tularensis, and burkholderia pseudomallei. universal primers were used to amplify highly conserved region located within the 16s rrna amplicon, followed by hybridized to pathogen-specific probes for identification of these five organisms. the other assay is based on multiplex pcr to simultaneously amplify five species-specific pathogen identification-targeted regi ... | 2012 | 22690123 |
| russian vaccines against especially dangerous bacterial pathogens. | in response to the epidemiological situation, live attenuated or killed vaccines against anthrax, brucellosis, cholera, glanders, plague and tularemia were developed and used for immunization of at-risk populations in the former soviet union. certain of these vaccines have been updated and currently they are used on a selective basis, mainly for high risk occupations, in the russian federation. except for anthrax and cholera these vaccines currently are the only licensed products available for p ... | 2014 | 26038506 |
| applying science: opportunities to inform disease management policy with cooperative research within a one health framework. | the ongoing ebola outbreak in west africa and the current saiga antelope die off in kazakhstan each represent very real and difficult to manage public or veterinary health crises. they also illustrate the importance of stable and funded surveillance and sound policy for intervention or disease control. while these two events highlight extreme cases of infectious disease (ebola) or (possible) environmental exposure (saiga), diseases such as anthrax, brucellosis, tularemia, and plague are all zoon ... | 2015 | 26779471 |
| the poly-γ-d-glutamic acid capsule surrogate of the bacillus anthracis capsule is a novel toll-like receptor 2 agonist. | bacillus anthracis is a pathogenic gram-positive bacterium that causes a highly lethal infectious disease, anthrax. the poly-γ-d-glutamic acid (pga) capsule is one of the major virulence factors of b. anthracis, along with exotoxins. pga enables b. anthracis to escape phagocytosis and immune surveillance. our previous study showed that pga activates the human macrophage cell line thp-1 and human dendritic cells, resulting in the production of the proinflammatory cytokine interleukin-1β (il-1β) ( ... | 2015 | 26195551 |
| biocidal and sporicidal efficacy of pathoster(®) 0.35% and pathoster(®) 0.50% against bacterial agents in potential bioterrorism use. | the use of products that can neutralize or significantly reduce the microbial load and that are not harmful to human health and the environment represents a milestone in the fight against the spread of infectious diseases. peracetic acid, besides being an excellent sterilizing and sporicidal agent, is harmless to humans and the environment when it is used in a common dosage. however, the high costs and loss of efficacy of the product very quickly after its reconstitution limit its use. we evalua ... | 2016 | 27482880 |
| production of functionally active and immunogenic non-glycosylated protective antigen from bacillus anthracis in nicotiana benthamiana by co-expression with peptide-n-glycosidase f (pngase f) of flavobacterium meningosepticum. | bacillus anthracis has long been considered a potential biological warfare agent, and therefore, there is a need for a safe, low-cost and highly efficient anthrax vaccine with demonstrated long-term stability for mass vaccination in case of an emergency. many efforts have been made towards developing an anthrax vaccine based on recombinant protective antigen (rpa) of b. anthracis, a key component of the anthrax toxin, produced using different expression systems. plants represent a promising reco ... | 2016 | 27101370 |
| rapid focused sequencing: a multiplexed assay for simultaneous detection and strain typing of bacillus anthracis, francisella tularensis, and yersinia pestis. | the intentional release of bacillus anthracis in the united states in 2001 has heightened concern about the use of pathogenic microorganisms in bioterrorism attacks. many of the deadliest bacteria, including the class a select agents bacillus anthracis, francisella tularensis, and yersinia pestis, are highly infectious via the pulmonary route when released in aerosolized form. hence, rapid, sensitive, and reliable methods for detection of these biothreats and characterization of their potential ... | 2013 | 23418519 |
| bioterrorism : a public health perspective. | the intentional release or threat of release of biologic agents (i.e. viruses, bacteria, fungi or their toxins) in order to cause disease or death among human population or food crops and livestock to terrorize a civilian population or manipulate the government in the present scenario of increased terrorist activity has become a real possibility. the most important step in the event of a bioterrorist attack is the identification of the event. this can be achieved by generating awareness, having ... | 2010 | 27408313 |
| swab protocol for rapid laboratory diagnosis of cutaneous anthrax. | the clinical laboratory diagnosis of cutaneous anthrax is generally established by conventional microbiological methods, such as culture and directly straining smears of clinical specimens. however, these methods rely on recovery of viable bacillus anthracis cells from swabs of cutaneous lesions and often yield negative results. this study developed a rapid protocol for detection of b. anthracis on clinical swabs. three types of swabs, flocked-nylon, rayon, and polyester, were evaluated by 3 ext ... | 2012 | 23035192 |
| anthrax lethal toxin and the induction of cd4 t cell immunity. | bacillus anthracis secretes exotoxins which act through several mechanisms including those that can subvert adaptive immunity with respect both to antigen presenting cell and t cell function. the combination of protective antigen (pa) and lethal factor (lf) forming lethal toxin (lt), acts within host cells to down-regulate the mitogen activated protein kinase (mapk) signaling cascade. until recently the mapk kinases were the only known substrate for lt; over the past few years it has become evid ... | 2012 | 23162703 |
| unusual bacterial infections and the pleura. | rickettsiosis, q fever, tularemia, and anthrax are all bacterial diseases that can affect the pleura. rocky mountain spotted fever (rmsf) and mediterranean spotted fever (msf) are caused by rickettsia rickettsii and rickettsia conorii, respectively. pleural fluid from a patient with msf had a neutrophil-predominant exudate. coxiellaburnetii is the causative agent of q fever. of the two cases described in the literature, one was an exudate with a marked eosinophilia while the other case was a tra ... | 2012 | 22977649 |
| rapid vascular responses to anthrax lethal toxin in mice containing a segment of chromosome 11 from the cast/ei strain on a c57bl/6 genetic background. | host allelic variation controls the response to b. anthracis and the disease course of anthrax. mouse strains with macrophages that are responsive to anthrax lethal toxin (lt) show resistance to infection while mouse strains with lt non-responsive macrophages succumb more readily. b6.cast.11m mice have a region of chromosome 11 from the cast/ei strain (a lt responsive strain) introgressed onto a lt non-responsive c57bl/6j genetic background. previously, b6.cast.11m mice were found to exhibit a r ... | 2012 | 22792226 |
| the potential of taqman array cards for detection of multiple biological agents by real-time pcr. | the taqman array card architecture, normally used for gene expression studies, was evaluated for its potential to detect multiple bacterial agents by real-time pcr. ten pcr assays targeting five biological agents (bacillus anthracis, burkholderia mallei, burkholderia pseudomallei, francisella tularensis, and yersinia pestis) were incorporated onto array cards. a comparison of pcr performance of each pcr in array card and singleplex format was conducted using dna extracted from pure bacterial cul ... | 2012 | 22540014 |
| phage-based platforms for the clinical detection of human bacterial pathogens. | bacteriophages (phages) have been utilized for decades as a means for uniquely identifying their target bacteria. due to their inherent natural specificity, ease of use, and straightforward production, phage possess a number of desirable attributes which makes them particularly suited as bacterial detectors. as a result, extensive research has been conducted into the development of phage, or phage-derived products to expedite the detection of human pathogens. however, very few phage-based diagno ... | 2012 | 23050221 |
| prioritizing risks and uncertainties from intentional release of selected category a pathogens. | this paper synthesizes available information on five category a pathogens (bacillus anthracis, yersinia pestis, francisella tularensis, variola major and lassa) to develop quantitative guidelines for how environmental pathogen concentrations may be related to human health risk in an indoor environment. an integrated model of environmental transport and human health exposure to biological pathogens is constructed which 1) includes the effects of environmental attenuation, 2) considers fomite cont ... | 2012 | 22412915 |
| development and comparison of two assay formats for parallel detection of four biothreat pathogens by using suspension microarrays. | microarrays provide a powerful analytical tool for the simultaneous detection of multiple pathogens. we developed diagnostic suspension microarrays for sensitive and specific detection of the biothreat pathogens bacillus anthracis, yersinia pestis, francisella tularensis and coxiella burnetii. two assay chemistries for amplification and labeling were developed, one method using direct hybridization and the other using target-specific primer extension, combined with hybridization to universal arr ... | 2012 | 22355407 |
| simultaneous and rapid detection of salmonella typhi, bacillus anthracis, and yersinia pestis by using multiplex polymerase chain reaction (pcr). | salmonella typhi, bacillus anthracis, and yersinia pestis are some serious human pathogens, which their early diagnosis is of great importance. salmonella typhi, bacillus anthracis, and yersinia pestis cause typhoid fever, anthrax, and plague respectively. these bacteria can be used to make biologic weapons. | 2013 | 24719692 |
| reverse transcription-pcr-electrospray ionization mass spectrometry for rapid detection of biothreat and common respiratory pathogens. | electrospray ionization mass spectrometry (esi-ms) analysis of reverse transcription (rt)-pcr amplicons from human respiratory samples allows for broad pathogen identification approximately 8 h after collection. we investigated the performance characteristics of a high-throughput rt-pcr-coupled esi-ms assay for distinguishing biothreat (bt) agents from common bacterial, fungal, and viral respiratory pathogens in bronchoalveolar lavage (bal) fluid specimens from subjects with suspected respirator ... | 2013 | 23903543 |
| detection of bacillus anthracis dna in complex soil and air samples using next-generation sequencing. | bacillus anthracis is the potentially lethal etiologic agent of anthrax disease, and is a significant concern in the realm of biodefense. one of the cornerstones of an effective biodefense strategy is the ability to detect infectious agents with a high degree of sensitivity and specificity in the context of a complex sample background. the nature of the b. anthracis genome, however, renders specific detection difficult, due to close homology with b. cereus and b. thuringiensis. we therefore elec ... | 2013 | 24039948 |
| rapid identification of bacillus anthracis spores in suspicious powder samples by using matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms). | rapid and reliable identification of bacillus anthracis spores in suspicious powders is important to mitigate the safety risks and economic burdens associated with such incidents. the aim of this study was to develop and validate a rapid and reliable laboratory-based matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) analysis method for identifying b. anthracis spores in suspicious powder samples. a reference library containing 22 different bacillus sp. s ... | 2013 | 23811517 |
| live attenuated tularemia vaccines: recent developments and future goals. | in the aftermath of the 2001 anthrax attacks in the u.s., numerous efforts were made to increase the level of preparedness against a biological attack both in the us and worldwide. as a result, there has been an increase in research interest in the development of vaccines and other countermeasures against a number of agents with the potential to be used as biological weapons. one such agent, francisella tularensis, has been the subject of a surge in the level of research being performed, leading ... | 2013 | 23764535 |
| transient lipopolysaccharide-induced resistance to aerosolized bacillus anthracis in new zealand white rabbits. | previous studies have demonstrated that prior infection by various bacterial pathogens induces nonspecific resistance to subsequent infection by other gram-negative and gram-positive bacterial pathogens. in the present study, we evaluated whether underlying inflammation enhanced host resistance to inhalational bacillus anthracis infection in new zealand white rabbits (spf; bordetella- and pasteurella-free). accordingly, rabbits were pretreated with either the inflammagen bacterial lps (60,000 eu ... | 2013 | 23759528 |
| a systematic screen of fda-approved drugs for inhibitors of biological threat agents. | the rapid development of effective medical countermeasures against potential biological threat agents is vital. repurposing existing drugs that may have unanticipated activities as potential countermeasures is one way to meet this important goal, since currently approved drugs already have well-established safety and pharmacokinetic profiles in patients, as well as manufacturing and distribution networks. therefore, approved drugs could rapidly be made available for a new indication in an emerge ... | 2013 | 23577127 |
| development of a panel of recombinase polymerase amplification assays for detection of biothreat agents. | syndromic panels for infectious disease have been suggested to be of value in point-of-care diagnostics for developing countries and for biodefense. to test the performance of isothermal recombinase polymerase amplification (rpa) assays, we developed a panel of 10 rpas for biothreat agents. the panel included rpas for francisella tularensis, yersinia pestis, bacillus anthracis, variola virus, and reverse transcriptase rpa (rt-rpa) assays for rift valley fever virus, ebola virus, sudan virus, and ... | 2013 | 23345286 |
| evaluation of the filmarray® system for detection of bacillus anthracis, francisella tularensis and yersinia pestis. | to evaluate the sensitivity and specificity of the biofire diagnostics filmarray(®) system in combination with their biothreat panel for the detection of bacillus anthracis (ba), francisella tularensis (ft) and yersinia pestis (yp) dna, and demonstrate the detection of ba spores. | 2013 | 23279070 |
| benefits of a european project on diagnostics of highly pathogenic agents and assessment of potential "dual use" issues. | quality assurance exercises and networking on the detection of highly infectious pathogens (quandhip) is a joint action initiative set up in 2011 that has successfully unified the primary objectives of the european network on highly pathogenic bacteria (enhpb) and of p4-laboratories (enp4-lab) both of which aimed to improve the efficiency, effectiveness, and response capabilities of laboratories directed at protecting the health of european citizens against high consequence bacteria and viruses ... | 2014 | 25426479 |
| the current state of bioterrorist attack surveillance and preparedness in the us. | the use of biological agents as weapons to disrupt established structures, such as governments and especially larger urban populations, has been prevalent throughout history. following the anthrax letters sent to various government officials in the fall of 2001, the us has been investing in prevention, surveillance, and preparation for a potential bioterrorism attack. additional funding authorized since 2002 has assisted the centers for disease control and prevention, the department of health an ... | 2014 | 25328421 |
| the impact of "omic" and imaging technologies on assessing the host immune response to biodefence agents. | understanding the interactions between host and pathogen is important for the development and assessment of medical countermeasures to infectious agents, including potential biodefence pathogens such as bacillus anthracis, ebola virus, and francisella tularensis. this review focuses on technological advances which allow this interaction to be studied in much greater detail. namely, the use of "omic" technologies (next generation sequencing, dna, and protein microarrays) for dissecting the underl ... | 2014 | 25333059 |
| disaster preparedness, pediatric considerations in primary blast injury, chemical, and biological terrorism. | both domestic and foreign terror incidents are an unfortunate outgrowth of our modern times from the oklahoma city bombings, sarin gas attacks in japan, the madrid train bombing, anthrax spores in the mail, to the world trade center on september 11(th), 2001. the modalities used to perpetrate these terrorist acts range from conventional weapons to high explosives, chemical weapons, and biological weapons all of which have been used in the recent past. while these weapons platforms can cause sign ... | 2014 | 24834398 |
| activation of the nlrp1b inflammasome independently of asc-mediated caspase-1 autoproteolysis and speck formation. | despite its clinical importance in infection and autoimmunity, the activation mechanisms of the nlrp1b inflammasome remain enigmatic. here we show that deletion of the inflammasome adaptor asc in balb/c mice and in c57bl/6 macrophages expressing a functional nlrp1b prevents anthrax lethal toxin (letx)-induced caspase-1 autoproteolysis and speck formation. however, asc(-/-) macrophages undergo normal letx-induced pyroptosis and secrete significant amounts of interleukin (il)-1β. in contrast, asc ... | 2014 | 24492532 |
| comparison of three next-generation sequencing platforms for metagenomic sequencing and identification of pathogens in blood. | the introduction of benchtop sequencers has made adoption of whole genome sequencing possible for a broader community of researchers than ever before. concurrently, metagenomic sequencing (mgs) is rapidly emerging as a tool for interrogating complex samples that defy conventional analyses. in addition, next-generation sequencers are increasingly being used in clinical or related settings, for instance to track outbreaks. however, information regarding the analytical sensitivity or limit of detec ... | 2014 | 24495417 |
| cross-institute evaluations of inhibitor-resistant pcr reagents for direct testing of aerosol and blood samples containing biological warfare agent dna. | rapid pathogen detection is crucial for the timely introduction of therapeutics. two groups (one in the united kingdom and one in the united states) independently evaluated inhibitor-resistant pcr reagents for the direct testing of substrates. in the united kingdom, a multiplexed bacillus anthracis (target) and bacillus subtilis (internal-control) pcr was used to evaluate 4 reagents against 5 pcr inhibitors and down-selected the taqman fast virus 1-step master mix (life technologies inc.). in th ... | 2014 | 24334660 |
| metabolic network analysis-based identification of antimicrobial drug targets in category a bioterrorism agents. | the 2001 anthrax mail attacks in the united states demonstrated the potential threat of bioterrorism, hence driving the need to develop sophisticated treatment and diagnostic protocols to counter biological warfare. here, by performing flux balance analyses on the fully-annotated metabolic networks of multiple, whole genome-sequenced bacterial strains, we have identified a large number of metabolic enzymes as potential drug targets for each of the three category a-designated bioterrorism agents ... | 2014 | 24454817 |
| agents of bioterrorism: curriculum and pedagogy in an online masters course. | the agents of bioterrorism course (bsbd 640, university of maryland university college) is a graduate level course created in response to an elevated need for scientists working in the field of medical countermeasures to biological and chemical weapons in the years following 9/11. students read and evaluate assigned current primary literature articles investigating medical countermeasures at each stage of development. in addition, students learn concepts of risk assessment, comparing and ranking ... | 2014 | 25089297 |
| development of a bead-based luminex assay using lipopolysaccharide specific monoclonal antibodies to detect biological threats from brucella species. | brucella, a gram-negative bacterium, is classified as a potential bioterrorism agent mainly due to the low dose needed to cause infection and the ability to transmit the bacteria via aerosols. goats/sheep, cattle, pigs, dogs, sheep and rodents are infected by b. melitensis, b. abortus, b. suis, b. canis, b. ovis and b. neotomae, respectively, the six classical brucella species. most human cases are caused by b. melitensis and b. abortus. our aim was to specifically detect brucellae with 'smooth' ... | 2015 | 26438077 |
| prevalence and distribution of soil-borne zoonotic pathogens in lahore district of pakistan. | a multidisciplinary, collaborative project was conducted to determine the prevalence and distribution of soil-borne zoonotic pathogens in lahore district of pakistan and ascertain its public health significance. using a grid-based sampling strategy, soil samples (n = 145) were collected from villages (n = 29, 5 samples/village) and examined for bacillus anthracis, burkholderia mallei/pseudomallei, coxiella burnetii, francisella tularensis, and yersinia pestis using real time pcr assays. chemical ... | 2015 | 26441860 |
| anthrax toxins in context of bacillus anthracis spores and spore germination. | the interaction of anthrax toxin or toxin components with b. anthracis spores has been demonstrated. germinating spores can produce significant amounts of toxin components very soon after the initiation of germination. in this review, we will summarize the work performed that has led to our understanding of toxin and spore interactions and discuss the complexities associated with these interactions. | 2015 | 26287244 |
| identification of highly pathogenic microorganisms by matrix-assisted laser desorption ionization-time of flight mass spectrometry: results of an interlaboratory ring trial. | in the case of a release of highly pathogenic bacteria (hpb), there is an urgent need for rapid, accurate, and reliable diagnostics. maldi-tof mass spectrometry is a rapid, accurate, and relatively inexpensive technique that is becoming increasingly important in microbiological diagnostics to complement classical microbiology, pcr, and genotyping of hpb. in the present study, the results of a joint exercise with 11 partner institutions from nine european countries are presented. in this exercise ... | 2015 | 26063856 |
| membrane-targeting dcap analogues with broad-spectrum antibiotic activity against pathogenic bacteria. | we performed a structure-activity relationship study of 2-((3-(3,6-dichloro-9h-carbazol-9-yl)-2-hydroxypropyl)amino)-2-(hydroxymethyl)propane-1,3-diol (dcap), which is an antibacterial agent that disrupts the membrane potential and permeability of bacteria. the stereochemistry of dcap had no effect on the biological activity of dcap. the aromaticity and electronegativity of the chlorine-substituted carbazole was required for activity, suggesting that its planar and dipolar characteristics orient ... | 2015 | 25941556 |
| targeted next-generation sequencing for the detection of ciprofloxacin resistance markers using molecular inversion probes. | antibiotic resistance (ar) is an epidemic of increasing magnitude requiring rapid identification and profiling for appropriate and timely therapeutic measures and containment strategies. in this context, ciprofloxacin is part of the first-line of countermeasures against numerous high consequence bacteria. significant resistance can occur via single nucleotide polymorphisms (snp) and deletions within ciprofloxacin targeted genes. ideally, use of ciprofloxacin would be prefaced with ar determinati ... | 2016 | 27174456 |
| alveolar macrophages infected with ames or sterne strain of bacillus anthracis elicit differential molecular expression patterns. | alveolar macrophages (ams) phagocytose bacillus anthracis following inhalation and induce the production of pro-inflammatory cytokines and chemokines to mediate the activation of innate immunity. ames, the virulent strain of b. anthracis, contains two plasmids that encode the antiphagocytic poly-γ-d-glutamic acid capsule and the lethal toxin. the attenuated sterne strain of b. anthracis, which lacks the plasmid encoding capsule, is widely adapted as a vaccine strain. although differences in the ... | 2014 | 24516547 |
| structure analysis of free and bound states of an rna aptamer against ribosomal protein s8 from bacillus anthracis. | several protein-targeted rna aptamers have been identified for a variety of applications and although the affinities of numerous protein-aptamer complexes have been determined, the structural details of these complexes have not been widely explored. we examined the structural accommodation of an rna aptamer that binds bacterial r-protein s8. the core of the primary binding site for s8 on helix 21 of 16s rrna contains a pair of conserved base triples that mold the sugar-phosphate backbone to s8. ... | 2014 | 25140011 |
| phages preying on bacillus anthracis, bacillus cereus, and bacillus thuringiensis: past, present and future. | many bacteriophages (phages) have been widely studied due to their major role in virulence evolution of bacterial pathogens. however, less attention has been paid to phages preying on bacteria from the bacillus cereus group and their contribution to the bacterial genetic pool has been disregarded. therefore, this review brings together the main information for the b. cereus group phages, from their discovery to their modern biotechnological applications. a special focus is given to phages infect ... | 2014 | 25010767 |
| cu(i)-mediated allosteric switching in a copper-sensing operon repressor (csor). | the copper-sensing operon repressor (csor) is representative of a major cu(i)-sensing family of bacterial metalloregulatory proteins that has evolved to prevent cytoplasmic copper toxicity. it is unknown how cu(i) binding to tetrameric csors mediates transcriptional derepression of copper resistance genes. a phylogenetic analysis of 227 duf156 protein members, including biochemically or structurally characterized csor/rcnr repressors, reveals that geobacillus thermodenitrificans (gt) csor charac ... | 2014 | 24831014 |
| peptide conjugated phosphorodiamidate morpholino oligomers increase survival of mice challenged with ames bacillus anthracis. | targeting bacterial essential genes using antisense phosphorodiamidate morpholino oligomers (pmos) represents an important strategy in the development of novel antibacterial therapeutics. pmos are neutral dna analogues that inhibit gene expression in a sequence-specific manner. in this study, several cationic, membrane-penetrating peptides were conjugated to pmos (ppmos) that target 2 bacterial essential genes: acyl carrier protein (acpp) and gyrase a (gyra). these were tested for their ability ... | 2012 | 22978365 |
| identification of pbc218/pbc210 genes of bacillus cereus g9241 in five florida soils using qpcr. | the distribution of the virulent plasmid pbc210 of b. cereus that carries several b. anthracis genes and has been implicated in lethal anthrax-like pulmonary disease is unknown. we screened our collection of 103 b. cereus isolates and 256 soil samples using a quantitative pcr (qpcr) assay that targeted three open reading frames putatively unique to pbc210. when tested with dna from 2 b. cereus strains carrying pbc210, and 64 gram-positive and 55 gram-negative bacterial species, the assay had 100 ... | 2014 | 27350995 |
| draft genome sequences of pseudomonas fluorescens bs2 and pusillimonas noertemannii bs8, soil bacteria that cooperate to degrade the poly-γ-d-glutamic acid anthrax capsule. | a mixed culture of pseudomonas fluorescens bs2 and pusillimonas noertemannii bs8 degraded poly-γ-d-glutamic acid; when the 2 strains were cultured separately, no hydrolytic activity was apparent. here we report the draft genome sequences of both soil isolates. | 2013 | 23405351 |
| parenteral administration of capsule depolymerase envd prevents lethal inhalation anthrax infection. | left untreated, inhalation anthrax is usually fatal. vegetative forms of bacillus anthracis survive in blood and tissues during infection due to elaboration of a protective poly-γ-d-glutamic acid (pdga) capsule that permits uncontrolled bacterial growth in vivo, eventually leading to overwhelming bacillosis and death. as a measure to counter threats from multidrug-resistant strains, we are evaluating the prophylactic and therapeutic potential of the pdga depolymerase envd, a stable and potent en ... | 2015 | 26438506 |
| the makes caterpillars floppy (mcf)-like domain of vibrio vulnificus induces mitochondrion-mediated apoptosis. | the multifunctional-autoprocessing repeats-in-toxin (martxvv) toxin of vibrio vulnificus plays a significant role in the pathogenesis of this bacterium through delivery of up to five effector domains to the host cells. previous studies have established that the martxvv toxin is linked to v. vulnificus dependent induction of apoptosis, but the region of the large multifunction protein essential for this activity was not previously identified. recently, we showed that the makes caterpillar floppy- ... | 2015 | 26351282 |
| immunization with a recombinant, pseudomonas fluorescens-expressed, mutant form of bacillus anthracis-derived protective antigen protects rabbits from anthrax infection. | protective antigen (pa), one of the components of the anthrax toxin, is the major component of human anthrax vaccine (biothrax). human anthrax vaccines approved in the united states and europe consist of an alum-adsorbed or precipitated (respectively) supernatant material derived from cultures of toxigenic, non-encapsulated strains of bacillus anthracis. approved vaccination schedules in humans with either of these vaccines requires several booster shots and occasionally causes adverse injection ... | 2015 | 26207820 |
| bacillus cereus biofilms-same, only different. | bacillus cereus displays a high diversity of lifestyles and ecological niches and include beneficial as well as pathogenic strains. these strains are widespread in the environment, are found on inert as well as on living surfaces and contaminate persistently the production lines of the food industry. biofilms are suspected to play a key role in this ubiquitous distribution and in this persistency. indeed, b. cereus produces a variety of biofilms which differ in their architecture and mechanism o ... | 2016 | 27458448 |
| panning of a phage display library against a synthetic capsule for peptide ligands that bind to the native capsule of bacillus anthracis. | bacillus anthracis is the causative agent of anthrax with the ability to not only produce a tripartite toxin, but also an enveloping capsule comprised primarily of γ-d-glutamic acid residues. the purpose of this study was to isolate peptide ligands capable of binding to the native capsule of b. anthracis from a commercial phage display peptide library using a synthetic form of the capsule consisting of 12 γ-d-glutamic acid residues. following four rounds of selection, 80 clones were selected ran ... | 2012 | 23029033 |
| undecaprenyl diphosphate synthase inhibitors: antibacterial drug leads. | there is a significant need for new antibiotics due to the rise in drug resistance. drugs such as methicillin and vancomycin target bacterial cell wall biosynthesis, but methicillin-resistant staphylococcus aureus (mrsa) and vancomycin-resistant enterococci (vre) have now arisen and are of major concern. inhibitors acting on new targets in cell wall biosynthesis are thus of particular interest since they might also restore sensitivity to existing drugs, and the cis-prenyl transferase undecapreny ... | 2014 | 24827744 |
| insights into methyltransferase specificity and bioactivity of derivatives of the antibiotic plantazolicin. | peptide antibiotics represent a class of conformationally constrained natural products of growing pharmaceutical interest. plantazolicin (pzn) is a linear, polyheterocyclic natural product with highly selective and potent activity against the anthrax-causing bacterium, bacillus anthracis. the bioactivity of pzn is contingent on dimethylation of its n-terminal arg residue by an s-adenosylmethionine-dependent methyltransferase. here, we explore the substrate tolerances of two homologous pzn methyl ... | 2015 | 25635336 |
| structure, bioactivity, and resistance mechanism of streptomonomicin, an unusual lasso peptide from an understudied halophilic actinomycete. | natural products are the most historically significant source of compounds for drug development. however, unacceptably high rates of compound rediscovery associated with large-scale screening of common microbial producers have resulted in the abandonment of many natural product drug discovery efforts, despite the increasing prevalence of clinically problematic antibiotic resistance. screening of underexplored taxa represents one strategy to avoid rediscovery. herein we report the discovery, isol ... | 2015 | 25601074 |
| surface display of recombinant proteins on escherichia coli by bcla exosporium of bacillus anthracis. | the anchoring motif is one of the most important aspects of cell surface display as well as efficient and stable display of target proteins. thus, there is currently a need for the identification and isolation of novel anchoring motifs. | 2013 | 24053632 |
| channel-forming bacterial toxins in biosensing and macromolecule delivery. | to intoxicate cells, pore-forming bacterial toxins are evolved to allow for the transmembrane traffic of different substrates, ranging from small inorganic ions to cell-specific polypeptides. recent developments in single-channel electrical recordings, x-ray crystallography, protein engineering, and computational methods have generated a large body of knowledge about the basic principles of channel-mediated molecular transport. these discoveries provide a robust framework for expansion of the de ... | 2014 | 25153255 |
| the structure of mlc titration factor a (mtfa/yeei) reveals a prototypical zinc metallopeptidase related to anthrax lethal factor. | mtfa of escherichia coli (formerly yeei) was previously identified as a regulator of the phosphoenolpyruvate (pep)-dependent:glucose phosphotransferase system. mtfa homolog proteins are highly conserved, especially among beta- and gammaproteobacteria. we determined the crystal structures of the full-length mtfa apoenzyme from klebsiella pneumoniae and its complex with zinc (holoenzyme) at 2.2 and 1.95 å, respectively. mtfa contains a conserved h(149)e(150)xxh(153)+e(212)+y(205) metallopeptidase ... | 2012 | 22467785 |
| germination and amplification of anthrax spores by soil-dwelling amoebas. | while anthrax is typically associated with bioterrorism, in many parts of the world the anthrax bacillus (bacillus anthracis) is endemic in soils, where it causes sporadic disease in livestock. these soils are typically rich in organic matter and calcium that promote survival of resilient b. anthracis spores. outbreaks of anthrax tend to occur in warm weather following rains that are believed to concentrate spores in low-lying areas where runoff collects. it has been concluded that elevated spor ... | 2012 | 22983962 |
| anthrax toxin protective antigen integrates poly-γ-d-glutamate and ph signals to sense the optimal environment for channel formation. | many toxins assemble into oligomers on the surface of cells. local chemical cues signal and trigger critical rearrangements of the oligomer, inducing the formation of a membrane-fused or channel state. bacillus anthracis secretes two virulence factors: a tripartite toxin and a poly-γ-d-glutamic acid capsule (γ-dpga). the toxin's channel-forming component, protective antigen (pa), oligomerizes to create a prechannel that forms toxic complexes upon binding the two other enzyme components, lethal f ... | 2012 | 23100533 |
| rapid induction of inflammatory lipid mediators by the inflammasome in vivo. | detection of microbial products by host inflammasomes is an important mechanism of innate immune surveillance. inflammasomes activate the caspase-1 (casp1) protease, which processes the cytokines interleukin (il)-1β and il-18, and initiates a lytic host cell death called pyroptosis. to identify novel casp1 functions in vivo, we devised a strategy for cytosolic delivery of bacterial flagellin, a specific ligand for the naip5 (nlr family, apoptosis inhibitory protein 5)/nlrc4 (nlr family, card-dom ... | 2012 | 22902502 |
| arsenic trioxide and other arsenical compounds inhibit the nlrp1, nlrp3, and naip5/nlrc4 inflammasomes. | inflammasomes are large cytoplasmic multiprotein complexes that activate caspase-1 in response to diverse intracellular danger signals. inflammasome components termed nucleotide-binding oligomerization domain-like receptor (nlr) proteins act as sensors for pathogen-associated molecular patterns, stress, or danger stimuli. we discovered that arsenicals, including arsenic trioxide and sodium arsenite, inhibited activation of the nlrp1, nlrp3, and naip5/nlrc4 inflammasomes by their respective activ ... | 2013 | 24337744 |