identification of bacillus anthracis pure inhibitors with antimicrobial activity.n(5)-carboxy-amino-imidazole ribonucleotide (n(5)-cair) mutase (pure), a bacterial enzyme in the de novo purine biosynthetic pathway, has been suggested to be a target for antimicrobial agent development. we have optimized a thermal shift method for high-throughput screening of compounds binding to bacillus anthracis pure. we used a low ionic strength buffer condition to accentuate the thermal shift stabilization induced by compound binding to bacillus anthracis pure. the compounds identified we ...201525737087
comparison of eleven commercially available rapid tests for detection of bacillus anthracis, francisella tularensis and yersinia pestis.yersinia pestis, bacillus anthracis and francisella tularensis cause serious zoonotic diseases and have the potential to cause high morbidity and mortality in humans. in case of natural outbreaks and deliberate or accidental release of these pathogens rapid detection of the bacteria is crucial for limitation of negative effects of the release. in the present study, we evaluated 11 commercially available rapid test kits for the detection of y. pestis, b. anthracis and f. tularensis in terms of se ...201525598285
immunopotentiation for bacterial biodefense.activation of the innate immune system can enhance resistance to a variety of bacterial and viral infections. in situations where the etiological agent of disease is unknown, such as a bioterror attack, stimulation of innate immunity may be particularly useful as induced immune responses are often capable of providing protection against a broad range of pathogens. in particular, the threat of an intentional release of a highly virulent bacterial pathogen that is either intrinsically resistant to ...201425373479
being prepared: bioterrorism and mass prophylaxis: part ii.although several biological agents have been recognized as presenting a significant threat to public health if used in a bioterrorist attack, those that are of greatest importance are known as the category a agents: bacillus anthracis (anthrax); variola major (smallpox); yersinia pestis (plague); francisella tularensis (tularemia); ribonucleic acid viruses (hemorrhagic fevers); and clostridium botulinum (botulism toxin). in the previous issue, part i of this review focused on the clinical presen ...201425356890
[the experiments conducted by japanese on human guinea pigs, and the use of biological weapons during the sino-japanese war (1937-1945)].starting from the end of the nineteenth century, and during the first four decades of the past century, japan showed considerable military expansion, on the back of a pan-asiatic and imperialistic ideology, comparable only to those expressed by wilhelmian and nazi germany. this growth led to japan playing an extremely important role in the asia-pacific continent, which unavoidably brought the country onto a collision course with the british empire and the united states of america. the japanese g ...201425269971
evaluation of up-converting phosphor technology-based lateral flow strips for rapid detection of bacillus anthracis spore, brucella spp., and yersinia pestis.bacillus anthracis, brucella spp., and yersinia pestis are zoonotic pathogens and biowarfare- or bioterrorism-associated agents that must be detected rapidly on-site from various samples (e.g., viscera and powders). an up-converting phosphor technology-based lateral flow (upt-lf) strip was developed as a point-of-care testing (poct) to satisfy the requirements of first-level emergency response. we developed upt-lf poct to quantitatively detect the three pathogens within 15 min. sample and operat ...201425144726
inactivation of bacterial and viral biothreat agents on metallic copper recent years several studies in laboratory settings and in hospital environments have demonstrated that surfaces of massive metallic copper have intrinsic antibacterial and antiviral properties. microbes are rapidly inactivated by a quick, sharp shock known as contact killing. the underlying mechanism is not yet fully understood; however, in this process the cytoplasmic membrane is severely damaged. pathogenic bacterial and viral high-consequence species able to evade the host immune system a ...201425100640
being prepared: bioterrorism and mass prophylaxis: part i.bioterrorism presents a real and omnipresent risk to public health throughout the world. more than 30 biological agents have been identified as possessing the potential to be deployed in a bioterrorist attack. those that have been determined to be of the greatest concern and possess the greatest potential of use in this arena are known as the category a agents: bacillus anthracis (anthrax); variola major (smallpox); yersinia pestis (plague); francisella tularensis (tularemia); viral hemorrhagic ...201425076398
construction and characterization of stable, constitutively expressed, chromosomal green and red fluorescent transcriptional fusions in the select agents, bacillus anthracis, yersinia pestis, burkholderia mallei, and burkholderia, we constructed stable, chromosomal, constitutively expressed, green and red fluorescent protein (gfp and rfp) as reporters in the select agents, bacillus anthracis, yersinia pestis, burkholderia mallei, and burkholderia pseudomallei. using bioinformatic approaches and other experimental analyses, we identified p0253 and p1 as potent promoters that drive the optimal expression of fluorescent reporters in single copy in b. anthracis and burkholderia spp. as well as their surrogate strains, r ...201425044501
application of r-pfe hyperimmune sera for concurrent detection of bacillus anthracis, yersinia pestis and staphylococcal enterotoxin evaluate the potential of an intergeneric multidomain recombinant chimeric protein for the simultaneous detection of bacillus anthracis, yersinia pestis and staphylococcal enterotoxin b.201424905217
combination of biobarcode assay with on-chip capillary electrophoresis for ultrasensitive and multiplex biological agent detection.early diagnosis of biological agents is of paramount importance to prevent the casualties and fatal disease in human during bioterrorism or biological warfare. in this study, we reported an efficient and sensitive multiplex biological agent detection method based on the dna biobarcode assay and the micro-capillary electrophoresis (μce) technology. monoplex as well as multiplex pathogen identification was performed using five targets including bacillus anthracis, francisella tularensis, yersinia ...201424878840
spectrally-resolved fluorescence cross sections of aerosolized biological live agents and simulants using five excitation wavelengths in a bsl-3 laboratory.a system for measuring spectrally-resolved fluorescence cross sections of single bioaerosol particles has been developed and employed in a biological safety level 3 (bsl-3) facility at edgewood chemical and biological center (ecbc). it is used to aerosolize the slurry or solution of live agents and surrogates into dried micron-size particles, and to measure the fluorescence spectra and sizes of the particles one at a time. spectrally-resolved fluorescence cross sections were measured for (1) bac ...201424718194
[bioterrorism and pathogenic microorganisms].in recent years the use of pathogenic microorganisms in acts of bioterrorism has been the subject of major concern in many countries. this paper presents a possible application of viruses and bacteria for warfare and terrorist purposes, as well as a laboratory diagnosis to identify those agents. the viruses of smallpox (orthopoxvirus), of hemorrhagic fever and those belonging to filovirus have been highlighted, inter alia, as agents of human infection with bioterrorist intent. among the bacteria ...201324473660
reverse line blot macroarray for simultaneous detection and characterization of four biological warfare agents.the need for a rapid detection and characterization of biowarfare (bw) agents cannot be over emphasized. with diverse array of potential bw pathogen available presently, rapid identification of the pathogen is crucial, so that specific therapy and control measures can be initiated. we have developed a multiplex polymerase chain reaction based reverse line blot macroarray to simultaneously detect four pathogens of bw importance viz. bacillus anthracis, yersinia pestis, brucella melitensis and bur ...201324426077
applications of docking and molecular dynamic studies on the search for new drugs against the biological warfare agents bacillus anthracis and yersinia pestis.the fear of biological warfare agents (bwa) use by terrorists is the major concern of the security agencies and health authorities worldwide today. the non-existence of vaccines or drugs against most bwa and the possibility of genetic modified strains has turned the search for new drugs to a state of urgency. fast in silico techniques are, therefore, perfect tools for this task once they can quickly provide structures of several new lead compounds for further experimental work. here we try to pr ...201324341424
evaluation of swabs and transport media for the recovery of yersinia pestis.the government accountability office report investigating the surface sampling methods used during the 2001 mail contamination with bacillus anthracis brought to light certain knowledge gaps that existed regarding environmental sampling with biothreat agents. should a contamination event occur that involves non-spore forming biological select agents, such as yersinia pestis, surface sample collection and processing protocols specific for these organisms will be needed. two y. pestis strains (vir ...201424184311
targeting dxp synthase in human pathogens: enzyme inhibition and antimicrobial activity of butylacetylphosphonate.the unique methylerythritol phosphate pathway for isoprenoid biosynthesis is essential in most bacterial pathogens. the first enzyme in this pathway, 1-deoxy-d-xylulose 5-phosphate (dxp) synthase, catalyzes a distinct thiamin diphosphate (thdp)-dependent reaction to form dxp from d-glyceraldehyde 3-phosphate (d-gap) and pyruvate and represents a potential anti-infective drug target. we have previously demonstrated that the unnatural bisubstrate analog, butylacetylphosphonate (bap), exhibits sele ...201424169798
detection of anthrax and other pathogens using a unique liquid array technology.a bead-based liquid hybridization assay, luminex(®) 100™, was used to identify four pathogenic bacteria, bacillus anthracis, clostridium botulinum, francisella tularensis subsp. tularensis, and yersinia pestis, and several close relatives. hybridization between pcr-amplified target sequences and probe sequences (located within the 23s ribosomal rna gene rrl and the genes related to the toxicity of each bacterium) was detected in single-probe or multiple-probe assays, depending on the organism. t ...201424147813
a sensitive & specific multiplex pcr assay for simultaneous detection of bacillus anthracis, yersinia pestis, burkholderia pseudomallei & brucella species.bacillus anthracis, yersinia pestis, burkholderia pseudomallei and brucella species are potential biowarfare agents. classical bacteriological methods for their identification are cumbersome, time consuming and of potential risk to the handler.201324056564
decontamination of a hospital room using gaseous chlorine dioxide: bacillus anthracis, francisella tularensis, and yersinia pestis.this study assessed the efficacy of gaseous chlorine dioxide for inactivation of bacillus anthracis, francisella tularensis, and yersinia pestis in a hospital patient care suite. spore and vegetative cells of bacillus anthracis sterne 34f2, spores of bacillus atrophaeus atcc 9372 and vegetative cells of both francisella tularensis atcc 6223 and yersinia pestis a1122 were exposed to gaseous chlorine dioxide in a patient care suite. organism inactivation was then assessed by log reduction in viabl ...201323971883
the use of colorimetric sensor arrays to discriminate between pathogenic bacteria.a colorimetric sensor array is a high-dimensional chemical sensor that is cheap, compact, disposable, robust, and easy to operate, making it a good candidate technology to detect pathogenic bacteria, especially potential bioterrorism agents like yersinia pestis and bacillus anthracis which feature on the center for disease control and prevention's list of potential biothreats. here, a colorimetric sensor array was used to continuously monitor the volatile metabolites released by bacteria in soli ...201323671629
fast identification of yersinia pestis, bacillus anthracis and francisella tularensis based on conventional pcr.rapid and accurate diagnostic tools for detection and identification of y pestis, b. anthracis and f. tularensis are essential for timely initial appropriate treatment of exposed individuals, which will be critical to their survival, as well as for reduction of the public health impact and the spread of the disease. the paper presents application of fast polymerases and fast dry electrophoresis in conventional pcr as an alternative for real-time pcr application for detection and identification o ...201324730142
[detection and identification of highly pathogenic bacteria within the framework of the eqadeba project--part ii: samples containing inactivated pathogens].the aim of the studies was analysis of methods applied and results of detection and identification of bacillus anthracis, yersinia pestis, francisella tularensis, brucella sp., bulkholderia mallei and b. pseudomallei in inactivated samples obtained within the framework of the third external quality assessment exercise (eqae) in the project ,,establishment of quality assurances for detection of highly pathogenic bacteria of potential bioterrorism risk (eqadeba)".201223230707
using a bacteriocin structure to engineer a phage lysin that targets yersinia pestis.purified phage lysins present an alternative to traditional antibiotics and work by hydrolysing peptidoglycan. phage lysins have been developed against gram-positive pathogens such as bacillus anthracis and streptococcus pneumoniae, where the peptidoglycan layer is exposed on the cell surface. addition of the lysin to a bacterial culture results in rapid death of the organism. gram-negative bacteria are resistant to phage lysins because they contain an outer membrane that protects the peptidogly ...201223176506
evaluation of two multiplex real-time pcr screening capabilities for the detection of bacillus anthracis, francisella tularensis and yersinia pestis in blood samples generated from murine infection models.two multiplex pcr screening capabilities (taqman array cards and filmarray) were evaluated for their ability to detect bacillus anthracis, francisella tularensis and yersinia pestis in blood samples obtained from respective murine infection models. blood samples were obtained from infected mice at 24 h intervals after exposure. multiplex pcr results were compared with standard blood culture and singleplex real-time pcr. across all three models, 71 mice were tested in total, within which a subset ...201222899777
comparison of nucleic acid extraction platforms for detection of select biothreat agents for use in clinical resource limited settings.high-quality nucleic acids are critical for optimal pcr-based diagnostics and pathogen detection. rapid sample processing time is important for the earliest administration of therapeutic and containment measures, especially in the case of biothreat agents. in this context, we compared the fujifilm quickgene-mini80 to qiagen's qiaamp mini purification kits for extraction of dna and rna for potential use in austere settings. qiagen (qiaamp) column-based extraction is the currently recommended puri ...201222750394
electroporation of a multivalent dna vaccine cocktail elicits a protective immune response against anthrax and plague.electroporation of dna vaccines represents a platform technology well positioned for the development of multivalent biodefense vaccines. to evaluate this hypothesis, three vaccine constructs were produced using codon-optimized genes encoding bacillus anthracis protective antigen (pa), and the yersinia pestis genes lcrv and f1, cloned into pvax1. a/j mice were immunized on a prime-boost schedule with these constructs using the electroporation-based trigrid delivery system. immunization with the i ...201222633906
cluster analysis of host cytokine responses to biodefense pathogens in a whole blood ex vivo exposure model (weem).rapid detection and therapeutic intervention for infectious and emerging diseases is a major scientific goal in biodefense and public health. toward this end, cytokine profiles in human blood were investigated using a human whole blood ex vivo exposure model, called weem.201222607329
immunogenicity and efficacy of an anthrax/plague dna fusion vaccine in a mouse model.the efficacy of multi-agent dna vaccines consisting of a truncated gene encoding bacillus anthracis lethal factor (lfn) fused to either yersinia pestis v antigen (v) or y . pestis f1 was evaluated. a/j mice were immunized by gene gun and developed predominantly igg1 responses that were fully protective against a lethal aerosolized b. anthracis spore challenge but required the presence of an additional dna vaccine expressing anthrax protective antigen to boost survival against aerosolized y. pest ...201222515653
evaluation of sample preparation methods for maldi-tof ms identification of highly dangerous propose a universal workflow of sample preparation method for the identification of highly pathogenic bacteria by maldi-tof ms.201222512320
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
synthesis, antibacterial, antioxidant activity and qsar studies of novel 2-arylidenehydrazinyl-4-arylthiazole analogues.a novel series of 2-arylidenehydrazinyl-4-arylthiazole analogues (3a-p) was designed and synthesized in excellent yields using a rapid, simple, efficient methodology. sixteen novel compounds were screened for in vitro antimicrobial activities against eleven bacteria, namely, staphylococcus aureus, listeria monocytogenes, enterococcus faecalis, bacillus subtilis, klebsiella pneumonia, citrobacter freundii, cronobacter sakazakii, salmonella enteritidis, escherichia coli, yersinia pestis, and pseud ...201425450634
identification of anziaic acid, a lichen depside from hypotrachyna sp., as a new topoisomerase poison inhibitor.topoisomerase inhibitors are effective for antibacterial and anticancer therapy because they can lead to the accumulation of the intermediate dna cleavage complex formed by the topoisomerase enzymes, which trigger cell death. here we report the application of a novel enzyme-based high-throughput screening assay to identify natural product extracts that can lead to increased accumulation of the dna cleavage complex formed by recombinant yersinia pestis topoisomerase i as part of a larger effort t ...201323593306
managing iron supply during the infection cycle of a flea borne pathogen, bartonella henselae.bartonella are hemotropic bacteria responsible for emerging zoonoses. most bartonella species appear to share a natural cycle that involves an arthropod transmission, followed by exploitation of a mammalian host in which they cause long-lasting intra-erythrocytic bacteremia. persistence in erythrocytes is considered an adaptation to transmission by bloodsucking arthropod vectors and a strategy to obtain heme required for bartonella growth. bartonella genomes do not encode for siderophore biosynt ...201324151576
a personal view of how paleomicrobiology aids our understanding of the role of lice in plague pandemics.we have been involved in the field of paleomicrobiology since 1998, when we used dental pulp to identify yersinia pestis as the causative agent of the great plague of marseille (1720). we recently designed a specific technique, "suicide pcr," that can prevent contamination. a controversy arose between two teams, with one claiming that dna must be altered to amplify it and the other group claiming that demographic data did not support the role of y. pestis in the black death (i.e., the great plag ...201627726806
a new clade of african body and head lice infected by bartonella quintana and yersinia pestis-democratic republic of the congo.the human body louse is known as a vector for the transmission of three serious diseases-specifically, epidemic typhus, trench fever, and relapsing fever caused by rickettsia prowazekii, bartonella quintana, and borrelia recurrentis, respectively-that have killed millions of people. it is also suspected in the transmission of a fourth pathogen, yersinia pestis, which is the etiologic agent of plague. to date, human lice belonging to the genus pediculus have been classified into three mitochondri ...201526392158
molecular survey of bartonella species and yersinia pestis in rodent fleas (siphonaptera) from chihuahua, mexico.rodent fleas from northwestern chihuahua, mexico, were analyzed for the presence of bartonella and yersinia pestis. in total, 760 fleas belonging to 10 species were tested with multiplex polymerase chain reaction analysis targeting the glta (338-bp) and pla genes (478-bp) of bartonella and y. pestis, respectively. although none was positive for y. pestis, 307 fleas were infected with bartonella spp., resulting in an overall prevalence of 40.4%. a logistic regression analysis indicated that the p ...201626576933
carrot cells: a pioneering platform for biopharmaceuticals production.carrot (daucus carota l.) is of importance in the molecular farming field as it constitutes the first plant species approved to produce biopharmaceuticals for human use. in this review, features that make carrot an advantageous species in the molecular farming field are analyzed and a description of the developments achieved with this crop thus far is presented. a guide for genetic transformation procedures is also included. the state of the art comprises ten vaccine prototypes against measles v ...201525572939
the genome, evolution and diversity of mycobacterium ulcerans.mycobacterium ulcerans (m. ulcerans) causes a devastating infection of the skin and underlying tissue commonly known as buruli ulcer (bu). genetic analyses indicate that m. ulcerans has a common ancestor with mycobacterium marinum (m. marinum) and has diverged from this fish and human pathogen perhaps around a million years ago. m. ulcerans is characterized by minimal genetic diversity and since it has a highly clonal population structure, genetic differences between individual isolates reflect ...201222306192
an update on the hazards and risks of forensic anthropology, part ii: field and laboratory considerations.this paper focuses on potential hazards and risks to forensic anthropologists while working in the field and laboratory in north america. much has changed since galloway and snodgrass published their seminal article addressing these issues. the increased number of forensic practitioners combined with new information about potential hazards calls for an updated review of these pathogens and chemicals. discussion of pathogen hazards (brucella, borrelia burgdorferi, yersinia pestis, clostridium tet ...201626389711
evaluation of the vitek 2 gram-negative (gn) microbial identification test card: collaborative study.a collaborative study was conducted to evaluate the performance of the vitek 2 gram-negative (gn) identification card for use with the vitek 2 automated microbial identification system. the gn test card is used in the identification of fermenting and nonfermenting gram-negative bacilli, including the select agent organisms brucella melitensis, francisella tularensis, burkholderia mallei, b. pseudomallei, and yersinia pestis. the vitek 2 gn card is based on 47 biochemical tests measuring carbon s ...201222816270
the in vivo extracellular life of facultative intracellular bacterial parasites: role in pathogenesis.classically labeled facultative intracellular pathogens are characterized by the ability to have an intracellular phase in the host, which is required for pathogenicity, while capable of extracellular growth in vitro. the ability of these bacteria to replicate in cell-free conditions is usually assessed by culture in artificial bacteriological media. however, the extracellular growth ability of these pathogens may also be expressed by a phase of extracellular infection in the natural setting of ...201322795971
mining host-pathogen protein interactions to characterize burkholderia mallei infectivity mechanisms.burkholderia pathogenicity relies on protein virulence factors to control and promote bacterial internalization, survival, and replication within eukaryotic host cells. we recently used yeast two-hybrid (y2h) screening to identify a small set of novel burkholderia proteins that were shown to attenuate disease progression in an aerosol infection animal model using the virulent burkholderia mallei atcc 23344 strain. here, we performed an extended analysis of primarily nine b. mallei virulence fact ...201525738731
a high-throughput screen for quorum-sensing inhibitors that target acyl-homoserine lactone synthases.many proteobacteria use n-acyl-homoserine lactone (acyl-hsl) quorum sensing to control specific genes. acyl-hsl synthesis requires unique enzymes that use s-adenosyl methionine as an acyl acceptor and amino acid donor. we developed and executed an enzyme-coupled high-throughput cell-free screen to discover acyl-hsl synthase inhibitors. the three strongest inhibitors were equally active against two different acyl-hsl synthases: burkholderia mallei bmai1 and yersinia pestis yspi. two of these inhi ...201323924613
inactivation of vegetative bacterial threat agents on environmental surfaces.following a wide-area biological terror attack, numerous decontamination technologies, techniques, and strategies will be required for rapid remediation. establishing an understanding of how disinfectants will perform under field conditions is of critical importance. the purpose of this study was to determine the efficacy of several liquid decontaminants, when used to inactivate vegetative biological agents on environmental surfaces. aluminum, carpet, concrete, glass, and wood coupons were inocu ...201323208274
upconversion nanocrystals mediated lateral-flow nanoplatform for in vitro detection.upconversion phosphors (ucps) that are free from interference from biological sample autofluorescence have attracted attention for in vivo and in vitro bioapplications. however, ucps need to be water-dispersible, nanosized, and highly luminous to realize broad applications. therefore, the aim of this research is to develop ucps that meet these comprehensive criteria for in vitro diagnosis. to combine nano size with high luminous intensity, β-nayf4:yb(3+),er(3+) upconversion nanocrystals (ucnps) ...201728067495
novel engineered cationic antimicrobial peptides display broad-spectrum activity against francisella tularensis, yersinia pestis and burkholderia pseudomallei.broad-spectrum antimicrobials are needed to effectively treat patients infected in the event of a pandemic or intentional release of a pathogen prior to confirmation of the pathogen's identity. engineered cationic antimicrobial peptides (ecaps) display activity against a number of bacterial pathogens including multi-drug-resistant strains. two lead ecaps, wlbu2 and wr12, were compared with human cathelicidin (ll-37) against three highly pathogenic bacteria: francisella tularensis, yersinia pesti ...201626673248
mplex: a method for simultaneous pathogen inactivation and extraction of samples for multi-omics profiling.the continued emergence and spread of infectious agents is of great concern, and systems biology approaches to infectious disease research can advance our understanding of host-pathogen relationships and facilitate the development of new therapies and vaccines. molecular characterization of infectious samples outside of appropriate biosafety containment can take place only subsequent to pathogen inactivation. herein, we describe a modified folch extraction using chloroform/methanol that facilita ...201728091625
rapid and high-throughput identification of recombinant bacteria with mass spectrometry construct a rapid and high-throughput assay for identifying recombinant bacteria based on mass spectrometry.201424758753
serologic survey for cross-species pathogens in urban coyotes (canis latrans), colorado, usa.abstract as coyotes (canis latrans) adapt to living in urban environments, the opportunity for cross-species transmission of pathogens may increase. we investigated the prevalence of antibodies to pathogens that are either zoonotic or affect multiple animal species in urban coyotes in the denver metropolitan area, colorado, usa, in 2012. we assayed for antibodies to canine parvovirus-2, canine distemper virus, rabies virus, toxoplasma gondii, yersinia pestis, and serotypes of leptospira interrog ...201425121408
inhibition of outer membrane proteases of the omptin family by aprotinin.bacterial proteases are important virulence factors that inactivate host defense proteins and contribute to tissue destruction and bacterial dissemination. outer membrane proteases of the omptin family, exemplified by escherichia coli ompt, are found in some gram-negative bacteria. omptins cleave a variety of substrates at the host-pathogen interface, including plasminogen and antimicrobial peptides. multiple omptin substrates relevant to infection have been identified; nonetheless, an effective ...201525824836
development and validation of an arthropod maceration protocol for zoonotic pathogen detection in mosquitoes and fleas.arthropod-borne diseases remain a pressing international public health concern. while progress has been made in the rapid detection of arthropod-borne pathogens via quantitative real-time (qpcr), or even hand-held detection devices, a simple and robust maceration and nucleic acid extraction method is necessary to implement biosurveillance capabilities. in this study, a comparison of maceration techniques using five types of beads followed by nucleic acid extraction and detection were tested usin ...201526047188
stress-caused anergy of leukocytes towards staphylococcal enterotoxin b and exposure transcriptome signatures.leucocytes from soldiers exposed to battlefield-like stress (rasp: rangers assessment and selection program) were exposed in vitro to staphylococcal enterotoxin b (seb). we assayed seb-induced regulation of gene expression, both in the presence and absence of severe stress, to generate two sets of gene profiles. one set of transcripts and micrornas were specific to post-rasp seb exposure, and another set were signatures of seb exposure common to both the pre- and post-rasp leucocytes. pathways a ...201726020283
intestinal microbial community diversity between healthy and orally infected rabbit with entamoeba histolytica by eric-pcr.enterobacterial repetitive intergenic consensus (eric)-pcr was applied to analyze the difference of intestinal microbial community diversity between healthy and orally infected rabbits with entamoeba histolytica. the dynamic changes in different parts of digestive system including the duodenum, jejunum, ileum, caecum, and rectum in healthy and infected rabbits at different time points were also tested. the intestinal microbial community of the control healthy rabbits was steady, and the total nu ...201222562215
whole-animal chemical screen identifies colistin as a new immunomodulator that targets conserved pathways.the purpose of this study was to take advantage of the nematode caenorhabditis elegans to perform a whole-animal chemical screen to identify potential immune activators that may confer protection against bacterial infections. we identified 45 marketed drugs, out of 1,120 studied compounds, that are capable of activating a conserved p38/pmk-1 mitogen-activated protein kinase pathway required for innate immunity. one of these drugs, the last-resort antibiotic colistin, protected against infections ...201425118236
evolution and structural dynamics of bacterial glycan binding adhesins.infectious disease processes like bacterial adherence or the activity of secreted toxins frequently gain host and tissue specificity by glycan binding interactions with the host glycome. recent functional and structural studies highlight the high niche specialization of bacterial lectins, but also reveal a remarkable plasticity in their glycan binding sites and mechanisms, to adapt to host glycome dynamics or changing environmental conditions at the site of infection. in this review we put empha ...201628043017
a recombinant trivalent fusion protein f1-lcrv-hsp70(ii) augments humoral and cellular immune responses and imparts full protection against yersinia pestis.plague is one of the most dangerous infections in humans caused by yersinia pestis, a gram-negative bacterium. despite of an overwhelming research success, no ideal vaccine against plague is available yet. it is well established that f1/lcrv based vaccine requires a strong cellular immune response for complete protection against plague. in our earlier study, we demonstrated that hsp70(ii) of mycobacterium tuberculosis modulates the humoral and cellular immunity of f1/lcrv vaccine candidates indi ...201627458447
pterin-sulfa conjugates as dihydropteroate synthase inhibitors and antibacterial agents.the sulfonamide class of antibiotics has been in continuous use for over 70years. they are thought to act by directly inhibiting dihydropteroate synthase (dhps), and also acting as prodrugs that sequester pterin pools by forming dead end pterin-sulfonamide conjugates. in this study, eight pterin-sulfonamide conjugates were synthesized using a novel synthetic strategy and their biochemical and microbiological properties were investigated. the conjugates were shown to competitively inhibit dhps, a ...201627423480
[pilot-scale purification of rf1-v fusion protein of yersinia pestis and characterization of its immunogenicity].recombinant fl-v (rfl-v) fusion protein is the main ingredient of the current candidate vaccine against yersinia pestis infection, which has been under investigation in clinical trial in usa. we investigated the soluble expression conditions of rf1-v in escherichia coli bl21 (de3) that we constructed before. after scale-up and optimization of fermentation processes, we got the optimized fermentation process parameters: the culture was induced at the middle exponential phase with 50 µmol/l of ipt ...201627363202
highly effective soluble and bacteriophage t4 nanoparticle plague vaccines against yersinia pestis.plague caused by yersinia pestis is an ancient disease, responsible for millions of deaths in human history. unfortunately, there is no fda-approved vaccine available. recombinant subunit vaccines based on two major antigens, caf 1 (f1) and lcrv (v), have been under investigation and showed promise. however, there are two main problems associated with these vaccines. first, the yersinia capsular protein f1 has high propensity to aggregate, particularly when expressed in heterologous systems such ...201627076150
quaternary structure of fur proteins, a new subfamily of tetrameric proteins.the ferric uptake regulator (fur) belongs to the family of the dna-binding metal-responsive transcriptional regulators. fur is a global regulator found in all proteobacteria. it controls the transcription of a wide variety of genes involved in iron metabolism but also in oxidative stress or virulence factor synthesis. when bound to ferrous iron, fur can bind to specific dna sequences, called fur boxes. this binding triggers the repression or the activation of gene expression, depending on the re ...201626886069
the yersiniabactin-associated atp binding cassette proteins ybtp and ybtq enhance escherichia coli fitness during high-titer cystitis.the yersinia high-pathogenicity island (hpi) is common to multiple virulence strategies used by escherichia coli strains associated with urinary tract infection (uti). among the genes in this island are ybtp and ybtq, encoding distinctive atp binding cassette (abc) proteins associated with iron(iii)-yersiniabactin import in yersinia pestis in this study, we compared the impact of ybtpq on a model e. coli cystitis strain during in vitro culture and experimental murine infections. a ybtpq-null mut ...201626883590
bacterial effector nanoparticles as breast cancer therapeutics.bacterial pathogens trigger cell death by a variety of mechanisms, including injection of effector proteins. effector proteins have great potential as anticancer agents because they efficiently subvert a variety of eukaryotic signaling pathways involved in cancer development, drug resistance, and metastasis. in breast cancer, mapk and nfκb pathways are known to be dysregulated. yopj, an effector from yersinia pestis, downregulates mapk and nfκb pathways to induce cell death in specific cell type ...201626800341
recombinant murine toxin from yersinia pestis shows high toxicity and β-adrenergic blocking activity in mice.yersinia pestis murine toxin (ymt) encoded on pmt1 is a 61-kda protein, a member of the phospholipase d superfamily, which is found in all the domains of life. it is considered to be an intracellular protein required for the survival of y. pestis in the midgut of the flea, but the exact role of ymt in the pathogenesis of y. pestis has not been clarified. purified ymt is highly toxic to mice and rats, but the exact mechanism of the animals' death is unclear. here, we prepared a recombinant ymt in ...201626774329
intrinsic plasmids influence micf-mediated translational repression of ompf in yersinia pestis.yersinia pestis, which is the causative agent of plague, has acquired exceptional pathogenicity potential during its evolution from y. pseudotuberculosis. two laterally acquired plasmids, namely, pmt1 and ppcp1, are specific to y. pestis and are critical for pathogenesis and flea transmission. small regulatory rnas (srnas) commonly function as regulators of gene expression in bacteria. micf, is a paradigmatic srna that acts as a post-transcriptional repressor through imperfect base pairing with ...201526347736
crp-mediated carbon catabolite regulation of yersinia pestis biofilm formation is enhanced by the carbon storage regulator protein, csra.the natural transmission of yersinia pestis is reliant upon biofilm blockage of the flea vector. however, the environmentally-responsive adaptive regulators which facilitate y. pestis biofilm production in accordance with the flea midgut milieu are not well understood. we seek to establish the impact of available carbon source metabolism and storage upon y. pestis biofilm production. our findings demonstrate that y. pestis biofilm production is subject to carbon catabolite regulation in which th ...201526305456
total biosynthesis and diverse applications of the nonribosomal peptide-polyketide siderophore yersiniabactin.yersiniabactin (ybt) is a mixed nonribosomal peptide-polyketide natural product natively produced by the pathogen yersinia pestis. the compound enables iron scavenging capabilities upon host infection and is biosynthesized by a nonribosomal peptide synthetase featuring a polyketide synthase module. this pathway has been engineered for expression and biosynthesis using escherichia coli as a heterologous host. in the current work, the biosynthetic process for ybt formation was improved through the ...201526025901
structural and functional characterization of tesb from yersinia pestis reveals a unique octameric arrangement of hotdog domains.acyl-coa thioesterases catalyse the hydrolysis of the thioester bonds present within a wide range of acyl-coa substrates, releasing free coash and the corresponding fatty-acyl conjugate. the tesb-type thioesterases are members of the te4 thioesterase family, one of 25 thioesterase enzyme families characterized to date, and contain two fused hotdog domains in both prokaryote and eukaryote homologues. only two structures have been elucidated within this enzyme family, and much of the current under ...201525849407
inhibition of zn(ii) binding type ia topoisomerases by organomercury compounds and hg(ii).type ia topoisomerase activities are essential for resolving dna topological barriers via an enzyme-mediated transient single strand dna break. accumulation of topoisomerase dna cleavage product can lead to cell death or genomic rearrangement. many antibacterial and anticancer drugs act as topoisomerase poison inhibitors that form stabilized ternary complexes with the topoisomerase covalent intermediate, so it is desirable to identify such inhibitors for type ia topoisomerases. here we report th ...201525798600
tyrr, the regulator of aromatic amino acid metabolism, is required for mice infection of yersinia pestis.yersinia pestis, the causative agent of plague, poses a serious health threat to rodents and human beings. tyrr is a transcriptional regulator (tyrr) that controls the metabolism of aromatic amino acids in escherichia coli. in this paper, tyrr played an important role in y. pestis virulence. inactivation of tyrr did not seem to affect the in vitro growth of this organism, but resulted in at least 10,000-fold attenuation compared with the wild-type (wt) strain upon subcutaneous infection to mice. ...201525729381
distinct biological activity of lipopolysaccharides with different lipid a acylation status from mutant strains of yersinia pestis and some members of genus psychrobacter.correlation between the chemical structure of lipid a from various gram-negative bacteria and biological activity of their lipopolysaccharide (lps) as an agonist of the innate immune receptor toll-like receptor 4 was investigated. purified lps species were quantitatively evaluated by their ability to activate the production of tumor necrosis factor (tnf) by murine bone marrow-derived macrophages in vitro. wild-type lps from plague-causing bacteria yersinia pestis was compared to lps from mutant ...201425716726
adhesive properties of yapv and paralogous autotransporter proteins of yersinia pestis.yersinia pestis is the causative agent of plague. this bacterium evolved from an ancestral enteroinvasive yersinia pseudotuberculosis strain by gene loss and acquisition of new genes, allowing it to use fleas as transmission vectors. infection frequently leads to a rapidly lethal outcome in humans, a variety of rodents, and cats. this study focuses on the y. pestis kim yapv gene and its product, recognized as an autotransporter protein by its typical sequence, outer membrane localization, and am ...201525690102
import and export of bacterial protein toxins.the paper provides a short overview of three investigated bacterial protein toxins, colicin m (cma) of escherichia coli, pesticin (pst) of yersinia pestis and hemolysin (shlab) of serratia marcescens. cma and pst are exceptional among colicins in that they kill bacteria by degrading the murein (peptidoglycan). both are released into the medium and bind to specific receptor proteins in the outer membrane of sensitive e. coli cells. subsequently they are translocated into the periplasm by an energ ...201525620353
effects of bacterial inactivation methods on downstream proteomic analysis.inactivation of pathogenic microbial samples is often necessary for the protection of researchers and to comply with local and federal regulations. by its nature, biological inactivation causes changes to microbial samples, potentially affecting observed experimental results. while inactivation-induced damage to materials such as dna has been evaluated, the effect of various inactivation strategies on proteomic data, to our knowledge, has not been discussed. to this end, we inactivated samples o ...201525620019
ypfφ: a filamentous phage acquired by yersinia pestis.yersinia pestis, the plague bacillus, has an exceptional pathogenicity for humans. the plague bacillus emerged very recently (≈3,000 years ago) from the enteropathogen y. pseudotuberculosis. early after its emergence, y. pestis became infected by a filamentous phage named ypfφ. during the microevolution of the plague bacillus, the phage remained in the various lineages as an unstable extrachromosomal element. however, in the sub branch that caused the third plague pandemic, ypfφ integrated itsel ...201425566217
hsp70 domain ii of mycobacterium tuberculosis modulates immune response and protective potential of f1 and lcrv antigens of yersinia pestis in a mouse ideal vaccine exists to control plague, a deadly dangerous disease caused by yersinia pestis. in this context, we cloned, expressed and purified recombinant f1, lcrv antigens of y. pestis and heat shock protein70 (hsp70) domain ii of m. tuberculosis in e. coli. to evaluate the protective potential of each purified protein alone or in combination, balb/c mice were immunized. humoral and cell mediated immune responses were evaluated. immunized animals were challenged with 100 ld50 of y. pestis ...201425474358
the role of pgac in klebsiella pneumoniae virulence and biofilm formation.klebsiella pneumoniae has emerged as one of the major pathogens for community-acquired and nosocomial infections. a four-gene locus that had a high degree similarity with escherichia coli pgaabcd and yersinia pestis hmshfrs was identified in k. pneumoniae genomes. the pgaabcd in e. coli encodes the envelope-spanning pga machinery for the synthesis and secretion of poly-β-linked n-acetylglucosamine (pnag). in a limited number of phylogenetically diverse bacteria, pnag was demonstrated to mediate ...201425450884
comparative study of the marr genes within the family enterobacteriaceae.marr genes are members of an ancient family originally identified in escherichia coli. this family is widely distributed in archaea and bacteria. homologues of this family have a conserved winged helix fold. marr proteins are involved in non-specific resistance systems conferring resistance to multiple antibiotics. extensive studies have shown the importance of marr proteins in physiology and pathogenicity in enterobacteria, but little is known about their origin or evolution. in this study, all ...201424723108
comprehensive logic based analyses of toll-like receptor 4 signal transduction pathway.among the 13 tlrs in the vertebrate systems, only tlr4 utilizes both myeloid differentiation factor 88 (myd88) and toll/interleukin-1 receptor (tir)-domain-containing adapter interferon-β-inducing factor (trif) adaptors to transduce signals triggering host-protective immune responses. earlier studies on the pathway combined various experimental data in the form of one comprehensive map of tlr signaling. but in the absence of adequate kinetic parameters quantitative mathematical models that revea ...201424699232
rabbit monoclonal antibodies directed at the t3ss effector protein yopm identify human pathogenic yersinia isolates.the yersinia outer protein m (yopm) is a type 3 secretion system (t3ss)-dependent effector protein of yersinia enterocolitica, yersinia pseudotuberculosis and yersinia pestis. although yopm is indispensable for full virulence, its molecular functions still remain largely elusive. recently, we could identify the recombinant yopm (ryopm) protein derived from the y. enterocolitica strain 8081 (jb580) as a cell-penetrating protein, which down-regulates the expression of various pro-inflammatory cyto ...201424636859
[endotoxin tolerance of mice to the effect of lipopolysaccharide and lipopolysaccharide-mice toxin complex of virulent strain yersinia pestis 231].comparative study of the effect of endotoxin tolerance of mice to the effect of lipopolysaccharide (lps37) and complex of lipopolysaccharide with mice toxin (lps37-mt) of a virulent yersinia pestis 231 strain.201424605658
posttranscriptional regulation of the yersinia pestis cyclic amp receptor protein crp and impact on virulence.the cyclic amp receptor protein (crp) is a transcriptional regulator that controls the expression of numerous bacterial genes, usually in response to environmental conditions and particularly by sensing the availability of carbon. in the plague pathogen yersinia pestis, crp regulates the expression of multiple virulence factors, including components of the type iii secretion system and the plasminogen activator protease pla. the regulation of crp itself, however, is distinctly different from tha ...201424520064
ail proteins of yersinia pestis and y. pseudotuberculosis have different cell binding and invasion activities.the yersinia pestis adhesin ail mediates host cell binding and facilitates delivery of cytotoxic yop proteins. ail from y. pestis and y. pseudotuberculosis is identical except for one or two amino acids at positions 43 and 126 depending on the y. pseudotuberculosis strain. ail from y. pseudotuberculosis strain ypiii has been reported to lack host cell binding ability, thus we sought to determine which amino acid difference(s) are responsible for the difference in cell adhesion. y. pseudotubercul ...201324386237
[transcriptional regulation of dps by oxyr protein in yersinia pestis].to study the transcriptional regulation mechanism of dps by oxyr in yersinia pestis.201324195375
human single-chain urokinase is activated by the omptins pgte of salmonella enterica and pla of yersinia pestis despite mutations of active site residues.fibrinolysis is important in cell migration and tightly regulated by specific inhibitors and activators; of the latter, urokinase (upa) associates with enhancement of cell migration. active upa is formed through cleavage of the single-chain upa (scupa). the salmonella enterica strain 14028r cleaved human scupa at the peptide bond lys158-ile159, the site cleaved also by the physiological activator human plasmin. the cleavage led to activation of scupa, while no cleavage or activation were detecte ...201323763588
integrating high-content imaging and chemical genetics to probe host cellular pathways critical for yersinia pestis infection.the molecular machinery that regulates the entry and survival of yersinia pestis in host macrophages is poorly understood. here, we report the development of automated high-content imaging assays to quantitate the internalization of virulent y. pestis co92 by macrophages and the subsequent activation of host nf-κb. implementation of these assays in a focused chemical screen identified kinase inhibitors that inhibited both of these processes. rac-2-ethoxy-3 octadecanamido-1-propylphosphocholine ( ...201323383093
fast and simple detection of yersinia pestis applicable to field investigation of plague foci.yersinia pestis, the plague bacillus, has a rodent-flea-rodent life cycle but can also persist in the environment for various periods of time. there is now a convenient and effective test (f1-dipstick) for the rapid identification of y. pestis from human patient or rodent samples, but this test cannot be applied to environmental or flea materials because the f1 capsule is mostly produced at 37°c. the plasminogen activator (pla), a key virulence factor encoded by a y. pestis-specific plasmid, is ...201323383008
recombinant salmonella vaccination technology and its application to human bacterial pathogens.salmonella enterica is a gram-negative intracellular bacterial pathogen which causes salmonellosis in humans and animals. during the past several decades, extensive studies have shown that the attenuated salmonella vaccine vector is an optimal vehicle for delivering passenger antigens to mucosal sites to induce humoral, cellular, and mucosal immunity. this immunity leads to protection against challenges with the wild-type pathogens from which the passenger antigens were derived. a myriad of stud ...201323360265
evaluation of protective potential of yersinia pestis outer membrane protein antigens as possible candidates for a new-generation recombinant plague vaccine.plague caused by yersinia pestis manifests itself in bubonic, septicemic, and pneumonic forms. although the u.s. food and drug administration recently approved levofloxacin, there is no approved human vaccine against plague. the capsular antigen f1 and the low-calcium-response v antigen (lcrv) of y. pestis represent excellent vaccine candidates; however, the inability of the immune responses to f1 and lcrv to provide protection against y. pestis f1(-) strains or those which harbor variants of lc ...201323239803
structure and uptake mechanism of bacteriocins targeting peptidoglycan renewal.bacteriocins are narrow-spectrum protein antibiotics released to kill related bacteria of the same niche. uptake of bacteriocins depends critically on the presence of an uptake receptor in the outer membrane, a translocation pore and an energy-dependent activating system of the inner membrane. most bacteriocins act on the inner membrane as pore-forming toxins or they target cytoplasmic dna/rna and ribosomal synthesis respectively. only two bacteriocins are known to become activated in the peripl ...201223176517
modeling bacteriophage amplification as a predictive tool for optimized maldi-tof ms-based bacterial detection.matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (maldi-tof ms) is a valuable tool for rapid bacterial detection and identification but is limited by the need for relatively high cell count samples, which have been grown under strictly controlled conditions. these requirements can be eliminated by the natural infection of a viable bacterial species of interest with a host-specific phage. this produces a rapid increase in phage protein concentrations in comparison to b ...201223147819
characterization of differential toll-like receptor responses below the optical diffraction limit.many membrane receptors are recruited to specific cell surface domains to form nanoscale clusters upon ligand activation. this step appears to be necessary to initiate cell signaling, including pathways in innate immune system activation. however, virulent pathogens such as yersinia pestis (the causative agent of plague) are known to evade innate immune detection, in contrast to similar microbes (such as escherichia coli) that elicit a robust response. this disparity has been partly attributed t ...201222807232
bacteriophages capable of lysing yersinia pestis and yersinia pseudotuberculosis: efficiency of plating tests and identification of receptors in escherichia coli k-12. 201222782755
bacterial tir-containing proteins and host innate immune system evasion.the innate immune system provides the first line of host defence against invading pathogens. key to upregulation of the innate immune response are toll-like receptors (tlrs), which recognize pathogen-associated molecular patterns (pamps) and trigger a signaling pathway culminating in the production of inflammatory mediators. central to this tlr signaling pathway are heterotypic protein-protein interactions mediated through toll/interleukin-1 receptor (tir) domains found in both the cytoplasmic r ...201322772799
structural engineering of a phage lysin that targets gram-negative pathogens.bacterial pathogens are becoming increasingly resistant to antibiotics. as an alternative therapeutic strategy, phage therapy reagents containing purified viral lysins have been developed against gram-positive organisms but not against gram-negative organisms due to the inability of these types of drugs to cross the bacterial outer membrane. we solved the crystal structures of a yersinia pestis outer membrane transporter called fyua and a bacterial toxin called pesticin that targets this transpo ...201222679291
two srna ryhb homologs from yersinia pestis biovar microtus expressed in vivo have differential hfq-dependent stability.small non-coding rnas (srnas) have been shown to modulate gene expression at the post-transcriptional level. ryhb, an iron-responsive srna, is conserved in escherichia coli and other enterobacteriae, indicating the downregulation of numerous genes during iron depletion. this srna is tightly regulated by the ferric uptake regulator (fur) and interacts with the rna binding protein hfq. hfq is generally purported to be essential for stabilizing srnas and promoting srna-mrna duplex formation. mainte ...201222659336
electricity-free, sequential nucleic acid and protein isolation.traditional and emerging pathogens such as enterohemorrhagic escherichia coli (ehec), yersinia pestis, or prion-based diseases are of significant concern for governments, industries and medical professionals worldwide. for example, ehecs, combined with shigella, are responsible for the deaths of approximately 325,000 children each year and are particularly prevalent in the developing world where laboratory-based identification, common in the united states, is unavailable (1). the development and ...201222635135
functional recruitment of the human complement inhibitor c4bp to yersinia pseudotuberculosis outer membrane protein ail.ail is a 17-kda chromosomally encoded outer membrane protein that mediates serum resistance (complement resistance) in the pathogenic yersiniae (yersinia pestis, y. enterocolitica, and y. pseudotuberculosis). in this article, we demonstrate that y. pseudotuberculosis ail from strains pb1, 2812/79, and ypiii/pib1 (serotypes o:1a, o:1b, and o:3, respectively) can bind the inhibitor of the classical and lectin pathways of complement, c4b-binding protein (c4bp). binding was observed irrespective of ...201222467648
genome analyses highlight the different biological roles of cellulases.cellulolytic enzymes have been the subject of renewed interest owing to their potential role in the conversion of plant lignocellulose to sustainable biofuels. an analysis of ∼1,500 complete bacterial genomes, presented here, reveals that ∼40% of the genomes of sequenced bacteria encode at least one cellulase gene. most of the bacteria that encode cellulases are soil and marine saprophytes, many of which encode a range of enzymes for cellulose hydrolysis and also for the breakdown of the other c ...201222266780
autotransporter proteins.this review focuses on the function of the escherichia coli and salmonella autotransporters for which a considerable amount of literature is available. members of the serine protease autotransporters of the enterobacteriaceae (spates) family are proteins from e. coli and shigella spp., which, like the neisseria and haemophilus influenzae iga1 proteases and hap, possess a consensus serine protease motif. the largest subfamily of autotransporters is defined by the aida conserved domain cog3468 and ...200526443517
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