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use of a cry1ac-resistant line of helicoverpa armigera (lepidoptera: noctuidae) to detect novel insecticidal toxin genes in bacillus thuringiensis.this paper describes a screening strategy incorporating resistant insect lines for discovery of new bacillus thuringiensis toxins against a background of known genes that would normally mask the activity of additional genes and the application of that strategy. a line of helicoverpa armigera with resistance to cry1ac (line isoc) was used to screen cry1ac-expressing strains of b. thuringiensis for additional toxins with activity against h. armigera. using this approach, a number of cry1ac-produci ...200818592310
isolations of cry2ab resistance in australian populations of helicoverpa armigera (lepidoptera: noctuidae) are allelic.alleles conferring resistance to cry2ab toxin occur at a frequency of 0.0033 in australian populations of helicoverpa armigera (hübner) (lepidoptera: noctuidae), and it is evident that detectable levels of resistance predated the introduction of transgenic cotton expressing this toxin. from 2002 until 2006, 10 such resistant alleles were scored. here, we examine colonies established from five of the 10 isolates by using complementation tests to determine their genetic relationships. the results ...200818613594
bacillus thuringiensis fermentation of wastewater and wastewater sludge--presence and characterization of chitinases.this study investigated the presence of chitinases in bacillus thuringiensis ssp kurstaki hd-1 (bt) fermented broths of wastewater sludge (non-hydrolyzed and hydrolyzed); starch industry wastewater and soyameal. chitinase activity was absent in soyameal and present in others. chitinase demonstrated peaks at ph 4.0 and temperatures 40 and 50 degrees c with higher activity between ph 4-5 and 10-11. the chitinase band on sds-page was found to be between 36 and 45 kda for non-hydrolyzed (nh) and hyd ...200818613615
discovery of a novel bacillus thuringiensis cry8d protein and the unique toxicity of the cry8d-class proteins against scarab beetles.a novel cry gene, cry8db, highly toxic to scarab beetles such as the japanese beetle, popillia japonica newman, was cloned from an isolate of bacillus thuringiensis(bt), bbt2-5. the cry8db gene has 3525bp nucleotides and codes for a protein of 1174 amino acid residues. the protein, cry8db, has typical bt characteristics such as the 8-block, conserved sequences and the three-domain 3d toxin structure as defined with cry3aa. when the amino acid sequence of cry8db was compared with that of cry8da w ...200818614174
[the gera operon is required for spore germination in bacillus thuringiensis].spore germination of bacillus could be triggered by germinants like l-alanine which is thought to bind to and stimulate specific receptors. the gera receptor responds to l-alanine in bacillus subtilis. a homologous gera operon of b. subtilis was isolated from bacillus thuringiensis subsp. kurstaki. rt-pcr showed that the transcription of the gera operon was switched on 3 hours after the initiation of sporulation and this operon was cotranscribed. disruption of the gera operon led to blockage of ...200818479051
overcoming the resistance of codling moth against conventional cydia pomonella granulovirus (cpgv-m) by a new isolate cpgv-i12.recently, codling moth (cm, cydia pomonella l.) populations with a significantly reduced susceptibility to c. pomonella granulovirus (cpgv) products have been observed in germany. a novel cpgv isolate, designated cpgv-i12, is able to overcome the cpgv resistance. cpgv-i12 originated from iran and showed superior efficacy in laboratory bioassays against a resistant cm strain (cpr), which has a 100-fold reduced susceptibility to commercially used isolate cpgv-m. determination of the median lethal ...200818479703
the cry48aa-cry49aa binary toxin from bacillus sphaericus exhibits highly restricted target specificity.the cry48aa/cry49aa binary toxin of bacillus sphaericus was recently discovered by its ability to kill culex quinquefasciatus mosquito larvae through a novel interaction between its two components. we have investigated the target specificity of this toxin and show it to be non-toxic to coleopteran, lepidopteran and other dipteran insects, including closely related aedes and anopheles mosquitoes. this represents an unusually restricted target range for crystal toxins from either b. sphaericus or ...200818484999
effectiveness of bacillus thuringiensis-transgenic chickpeas and the entomopathogenic fungus metarhizium anisopliae in controlling helicoverpa armigera (lepidoptera: noctuidae).the use of genetically modified (bt) crops expressing lepidopteran-specific cry proteins derived from the soil bacterium bacillus thuringiensis is an effective method to control the polyphagous pest helicoverpa armigera. as h. armigera potentially develops resistance to cry proteins, bt crops should be regarded as one tool in integrated pest management. therefore, they should be compatible with biological control. bioassays were conducted to understand the interactions between a cry2aa-expressin ...200818487396
composition of forage and grain from second-generation insect-protected corn mon 89034 is equivalent to that of conventional corn (zea mays l.).insect-protected corn hybrids containing cry insecticidal proteins derived from bacillus thuringiensis have protection from target pests and provide effective management of insect resistance. mon 89034 hybrids have been developed that produce both the cry1a.105 and cry2ab2 proteins, which provide two independent modes of insecticidal action against the european corn borer ( ostrinia nubilalis ) and other lepidopteran insect pests of corn. the composition of mon 89034 corn was compared to convent ...200818489113
results of a 13-week safety assurance study with rats fed grain from corn rootworm-protected, glyphosate-tolerant mon 88017 corn.presented are the results of a 13-week rat feeding study with grain from mon 88017 corn (brand name yieldgard vt rootworm/rr2), protected from feeding damage caused by corn rootworm and tolerant to glyphosate, the active ingredient in roundup agricultural herbicides. corn rootworm protection is accomplished through the introduction of crybb1 coding sequence from bacillus thuringiensis into the corn genome for in planta production of a bioactive form of cry3bb1 protein. also included in the genom ...200818492601
the in vivo digestive fate of the cry3bb1 protein in laying hens fed diets containing mon 863 corn.two trials were conducted to assess the fate of the cry3bb1 protein from yieldgard rootworm corn (mon 863) when fed to laying hens. in the first trial, 2 diets, 1 formulated with mon 863 and 1 with conventional corn, were fed to laying hens (12 replicate cages with 4 hens/cage per treatment) for 8 wk. daily feed intake (fi), egg production (ep), and bw were measured. prestudy fecal samples, wk 4 and 8 egg and fecal samples, and hepatic and pectoralis tissue samples were collected from 12 killed ...200818492996
a novel negative regulatory factor for nematicidal cry protein gene expression in bacillus thuringiensis.a 3-kb hindiii fragment bearing the cry6aa2 gene and the adjacent and intergenic regions was cloned from bacillus thuringiensis strain ybt-1518. two open reading frames (orfs), namely, orf1 (termed cry6aa2) and orf2 that were separated by an inverted-repeat sequence were identified. orf1 encoded a 54-kda protein that exhibited high toxicity to the plant-parasitic nematode meloidogyne hapla. the orf2 expression product was not detected by sds-page, but its mrna was detected by rt-pcr. the orf2 co ...200818600043
riboprint and virulence gene patterns for bacillus cereus and related species.a total of 72 bacillus cereus strains and 5 bacillus thuringiensis strains were analyzed for their ecori ribogroup by ribotyping and for the presence or absence of seven virulence-associated genes. from these 77 strains, 42 distinctive ribogroup were identified using ecori, but the two species could not be discriminated by their ecori ribogroup. the 77 strains were also examined by pcr for the presence of seven virulence-associated genes, cerab, pi-plc, entfm, bcet, hbla, hblc, and hbld. all fiv ...200818600061
a preliminary study of the bioactivity of vegetative proteins extracted from malaysian bacillus thuringiensis isolates.vegetative proteins from malaysian strains of bacillus thuringiensis israelensis strains (bt 11, bt 12, bt 15, bt 16, bt 17, bt 21 and bt 22) and bacillus sphaericus h-25 strains (bs 1 and bs 2) were screened for haemolytic, cytotoxic and larvicidal activity. sds-page profiles of the bacillus thuringiensis strains studied consistently showed major bands of 33-37 kda and 47 kda. bt 16 also showed two bands of 66 kda and 45 kda similar to the previously reported binary vegetative protein, vip1ac ( ...200818600206
exploring poly-beta-hydroxy-butyrate metabolism through network-based extreme pathway analysis.the objective of this article is to obtain a more detailed insight into poly-beta-hydroxybutyrate (phb) metabolism through network-based metabolic pathway analysis. we employ extreme pathways to perform this study, because calculating and interpreting extreme pathways is a promising way for pathway analysis and metabolic engineering. after giving an in silico model of butanoate metabolism of bacillus thuringiensis 97-27 (btk), extreme pathways were calculated and classified. furthermore, the typ ...200818600631
spore stage expression of a vegetative insecticidal gene increase toxicity of bacillus thuringiensis subsp. aizawai sp41 against spodoptera exigua.to enhance the toxicity of the bacillus thuringiensis subsp. aizawai strain sp41 (sp41), the vegetative insecticidal protein (vip) gene vip3a from sp41 was redirected to the sporulation stage by replacing its native promoter with the strong promoter p19 of the cry11aa operon. compared to the wild type, sp41 with pvip (vip3a with its native promoter and ter) had the relative expression ratios of 457, 548, and 290 at 8, 14, and 20 h of cultivation, respectively, as measured by quantitative reverse ...200818602953
real-time pcr system targeting a chromosomal marker specific for bacillus anthracis.specific identification of bacillus anthracis and differentiation from closely related bacillus cereus and bacillus thuringiensis strains is still a major diagnostic problem. commercially available diagnostic kits targeting plasmid-markers cannot differentiate between b. anthracis, non-anthracis bacillus species harbouring anthrax-specific virulence plasmids, and plasmidless b. anthracis strains. a taqman pcr assay was designed targeting sequences of gene locus ba_5345 of the b. anthracis strain ...200818602986
identification and characterization of a novel cytotoxic protein, parasporin-4, produced by bacillus thuringiensis a1470 strain.in 1901, a unique bacterium was isolated as a pathogen of the sotto disease of the silkmoth larvae, and later in 1915, the organism was described as bacillus thuringiensis. since the discovery, this bacterium has widely attracted attention of not only insect pathologists but many other scientists who are interested in strong and specific insecticidal activity associated with inclusion bodies of b. thuringiensis. this has led to the recent worldwide development of b. thuringiensis-based microbial ...200818606366
glycosyltransferase: a specific marker for the discrimination of bacillus anthracis from the bacillus cereus group.bacillus anthracis, the aetiological agent of anthrax, has been taxonomically classified with the bacillus cereus group, which comprises b. cereus, bacillus thuringiensis, bacillus mycoides, bacillus pseudomycoides and bacillus weihenstephanensis. although the pathogenesis and ecological manifestations may be different, b. anthracis shares a high degree of dna sequence similarity with its group member species. as a result, the discrimination of b. anthracis from its close relatives in the b. cer ...200818287289
bayesian-integrated microbial forensics.in the aftermath of the 2001 anthrax letters, researchers have been exploring ways to predict the production environment of unknown-source microorganisms. culture medium, presence of agar, culturing temperature, and drying method are just some of the broad spectrum of characteristics an investigator might like to infer. the effects of many of these factors on microorganisms are not well understood, but the complex way in which microbes interact with their environments suggests that numerous anal ...200818390682
bt corn in spain--the performance of the eu's first gm crop. 200818392015
microbial populations and enzyme activities in soil in situ under transgenic corn expressing cry proteins from bacillus thuringiensis.transgenic bt crops produce insecticidal cry proteins that are released to soil in plant residues, root exudates, and pollen and that may affect soil microorganisms. as a continuation of studies in the laboratory and a plant-growth room, a field study was conducted at the rosemount experiment station of the university of minnesota. three bt corn varieties that express the cry1ab protein, which is toxic to the european corn borer (ostrinia nubilalis hübner), and one bt corn variety that expresses ...200818396552
effect of bacterial infection on antioxidant activity and lipid peroxidation in the midgut of galleria mellonella l. larvae (lepidoptera, pyralidae).bacillus thuringiensis is one of the most widely used sources of biorational pesticides, as well as a key source of genes for transgenic expression to provide pest resistance in plants. in this study the effect of bacillus thuringiensis ssp. galleriae (bt) infection on the activity of superoxide dismutase (sod), glutathione s-transferase (gst), catalase (cat), concentrations of oxidated and reduced thiols (rssr/rsh) and malondialdehyde (mda) was tested in the midgut of galleria mellonella larvae ...200818400562
pcr-based method for the detection of cry genes in local isolates of bacillus thuringiensis from thailand.a total of 134 isolates of bacillus thuringiensis obtained from different geographical and ecological origins in thailand were analyzed to determine the distribution and diversity of cry1, cry2 and cry9 genes encoding for cry proteins toxic to lepidopteran insects. strains containing cry1-type genes (109/134 or 81.3%) were found at the same frequency as strains harboring cry2 gene (108/134 or 80.6%) whereas only 50 strains contained cry9 gene (50/134 or 37.3%). seventeen percent (23/134) of the ...200818407288
anopheles gambiae cadherin agcad1 binds the cry4ba toxin of bacillus thuringiensis israelensis and a fragment of agcad1 synergizes toxicity.a midgut cadherin agcad1 cdna was cloned from anopheles gambiae larvae and analyzed for its possible role as a receptor for the cry4ba toxin of bacillus thuringiensis strain israelensis. the agcad1 cadherin encodes a putative 1735-residue protein organized into an extracellular region of 11 cadherin repeats (cr) and a membrane-proximal extracellular domain (mped). agcad1 mrna was detected in midgut of larvae by polymerase chain reaction (pcr). the agcad1 protein was localized, by immunochemistry ...200818407662
investigating the properties of bacillus thuringiensis cry proteins with novel loop replacements created using combinatorial molecular biology.cry proteins are a large family of crystalline toxins produced by bacillus thuringiensis. individually, the family members are highly specific, but collectively, they target a diverse range of insects and nematodes. domain ii of the toxins is important for target specificity, and three loops at its apex have been studied extensively. there is considerable interest in determining whether modifications in this region may lead to toxins with novel specificity or potency. in this work, we studied th ...200818408065
membrane insertion of the bacillus thuringiensis cry1ab toxin: single mutation in domain ii block partitioning of the toxin into the brush border membrane.the umbrella and penknife models hypothesize that insecticidal bacillus thuringiensis cry toxins partition into the apical membrane of the insect midgut by insertion of only two alpha-helices from domain i of the protein, alpha-helices 4 and 5 in the case of the umbrella model and alpha-helices 5 and 6 in the case of the penknife model. neither model envisages membrane partitioning by domains ii and iii. in this study, we present data suggesting that mutations in the domain ii residue, f371, aff ...200818457427
allele frequency of resistance to bacillus thuringiensis cry1ab corn in louisiana populations of sugarcane borer (lepidoptera: crambidae).transgenic bacillus thuringiensis (bt) corn, zea mays l., has been widely used to manage a corn borer complex in the mid-southern region of the united states. the sugarcane borer, diatraea saccharalis (f.) (lepidoptera: crambidae), has become a dominant cornstalk boring species in some areas of this region, especially in louisiana. therefore, management of sugarcane borer resistance to bt corn is critical to ensure the long-term sustainability of bt corn for the region. this study screened 280 t ...200818459416
effects of refuge contamination by transgenes on bt resistance in pink bollworm (lepidoptera: gelechiidae).refuges of non-bacillus thuringiensis (bt) cotton, gossypium hirsutum l., are used to delay bt resistance in pink bollworm, pectinophora gossypiella (saunders) (lepidoptera: gelechiidae), a pest that eats cotton seeds. contamination of refuges by bt transgenes could reduce the efficacy of this strategy. previously, three types of contamination were identified in refuges: 1) homozygous bt cotton plants, with 100% of their seeds producing the bt toxin cry1ac; 2) hemizygous bt plants with 70-80% of ...200818459418
toxicity and characterization of cotton expressing bacillus thuringiensis cry1ac and cry2ab2 proteins for control of lepidopteran pests.cry1ac protoxin (the active insecticidal toxin in both bollgard and bollgard ii cotton [gossypium hirsutum l.]), and cry2ab2 toxin (the second insecticidal toxin in bollgard ii cotton) were bioassayed against five of the primary lepidopteran pests of cotton by using diet incorporation. cry1ac was the most toxic to heliothis virescens (f.) and pectinophora gossypiella (saunders), demonstrated good activity against helicoverpa zea (boddie), and had negligible toxicity against spodoptera exigua (hü ...200818459423
frequency and severity of western bean cutworm (lepidoptera: noctuidae) ear damage in transgenic corn hybrids expressing different bacillus thuringiensis cry toxins.the frequency and severity of corn ear damage caused by western bean cutworm, striacosta albicosta (smith), were measured on transgenic corn, zea mays l., hybrids expressing two different insecticidal bacillus thuringiensis (bt) (berliner) cry toxins (bt) selected to protect against damage caused by larval european corn borer, ostrinia nubilalis (hübner). a field cage experiment deliberately infested with western bean cutworm egg masses resulted in less damage in the hybrid expressing the cry1f ...200818459424
bt crop effects on functional guilds of non-target arthropods: a meta-analysis.uncertainty persists over the environmental effects of genetically-engineered crops that produce the insecticidal cry proteins of bacillus thuringiensis (bt). we performed meta-analyses on a modified public database to synthesize current knowledge about the effects of bt cotton, maize and potato on the abundance and interactions of arthropod non-target functional guilds.200818461164
assessing the impact of the biological control agent bacillus thuringiensis on the indigenous microbial community within the pepper plant phyllosphere.although biological control agents (bcas) have been used extensively for controlling insects and pathogens of plants, little is known regarding the effects of such agents on the indigenous microbial communities within the plant phyllosphere. we assessed the effect of the bca bacillus thuringiensis (bt) on the microbial communities within the pepper plant phyllosphere using culture-independent methodologies. phospholipid fatty acid (plfa) analysis suggested that the bacterial and fungal biomass w ...200818462395
assessment of protoxin composition of bacillus thuringiensis strains by use of polyacrylamide gel block and mass spectrometry.assessment of protoxin composition in bacillus thuringiensis parasporal crystals is principally hampered by the fact that protoxins in a single strain usually possess high sequence homology. therefore, new strategies towards the identification of protoxins have been developed. here, we established a powerful method through embedding solubilized protoxins in a polyacrylamide gel block coupled to liquid chromatography-tandem mass spectrometry (lc-ms/ms) analysis of in-gel-generated peptides for pr ...200818463863
the theoretical 3d structure of bacillus thuringiensis cry5ba.cry5ba is a delta-endotoxin produced by bacillus thuringiensis ps86a1 nrrl b-18900. it is active against nematodes and has great potential for nematode control. here, we predict the first theoretical model of the three-dimensional (3d) structure of a cry5ba toxin by homology modeling on the structure of the cry1aa toxin, which is specific to lepidopteran insects. cry5ba resembles the previously reported cry1aa toxin structure in that they share a common 3d structure with three domains, but there ...200818504623
influence of amino nitrogen in the culture medium enhances the production of delta-endotoxin and biomass of bacillus thuringiensis var. israelensis for the large-scale production of the mosquito control agent.we reported here the role of amino nitrogen in the commercial production of bacillus thuringiensis var. israelensis media design. the insect pathogen b. thuringiensis var. israelensis was cultured in different media containing varying initial levels of amino nitrogen sources obtained from three different commercial venders. the biomass, mosquito larval toxicity and spore count produced were measured during the fermentation process. the results showed that the higher level of initial amino nitrog ...200818509685
bacillus thuringiensis pore-forming toxins trigger massive shedding of gpi-anchored aminopeptidase n from gypsy moth midgut epithelial cells.the insecticidal cry proteins produced by bacillus thuringiensis strains are pore-forming toxins (pfts) that bind to the midgut brush border membrane and cause extensive damage to the midgut epithelial cells of susceptible insect larvae. force-feeding b. thuringiensis pfts to lymantria dispar larvae elicited rapid and massive shedding of a glycosylphosphatidylinositol (gpi)-anchored aminopeptidase n (apn) from midgut epithelial cells into the luminal fluid, and depletion of the membrane-anchored ...200818510972
adsorption of cry1ab protein isolated from bt transgenic rice on bentone, kaolin, humic acids, and soils.adsorption on a soil matrix of the insecticidal protein from bacillus thuringiensis ( bt) transgenic plants affects their accumulation and release and, hence, bioavailability in soil. cry1ab protein isolated from bt transgenic rice was used to evaluate the adsorption and desorption on bentone, kaolin, and humic acids (has). the adsorption equilibrium of cry1ab protein was reached within 1-2 h for bentone and kaolin and within 4-8 h for has. the adsorption isotherms were better described by linea ...200818512935
isolation of naturally associated bacteria of necromenic pristionchus nematodes and fitness consequences.nematodes and bacteria are major components of the soil ecosystem. many nematodes use bacteria for food, whereas others evolved specialized bacterial interactions ranging from mutualism to parasitism. little is known about the biological mechanisms by which nematode-bacterial interactions are achieved, largely because in the laboratory nematodes are often cultured under artificial conditions. we investigated the bacterial interactions of nematodes from the genus pristionchus that have a strong a ...200818515723
a critical assessment of the effects of bt transgenic plants on parasitoids.the ecological safety of transgenic insecticidal plants expressing crystal proteins (cry toxins) from the bacterium bacillus thuringiensis (bt) continues to be debated. much of the debate has focused on nontarget organisms, especially predators and parasitoids that help control populations of pest insects in many crops. although many studies have been conducted on predators, few reports have examined parasitoids but some of them have reported negative impacts. none of the previous reports were a ...200818523682
atomic force microscopy imaging of bacillus thuringiensis cry1 toxins interacting with insect midgut apical membranes.atomic force microscopy was used to image bacillus thuringiensis (bt) toxins interacting with their natural targets, manduca sexta midgut brush border membranes (bbms), as well as with dipalmitoylphosphatidylcholine-dioleoylphosphatidylcholine (dppc-dopc) solid-supported lipid bilayers. in lipid bilayers, cry1aa formed structures 30-60 nm wide and 3-7 nm high, mostly at the interface of domains formed by the two different lipids or at the edge of dopc-enriched domains. bbm vesicles, in the absen ...200818523711
ecological consequences of ingestion of bacillus cereus on bacillus thuringiensis infections and on the gut flora of a lepidopteran host.the bacillus cereus group comprises a diverse array of non-pathogenic bacteria as well as pathogens such as bacillus thuringiensis. their spores are found together in soil and leaves and are therefore likely to commonly interact within hosts. mixed infections of pathogenic b. thuringiensis and non-pathogenic strains have been little studied, despite their potential impact on biological control and the evolutionary ecology of virulence. antibiotic secreting strains of b. cereus have been shown to ...200818533180
brazilian free-tailed bats as insect pest regulators in transgenic and conventional cotton crops.during the past 12000 years agricultural systems have transitioned from natural habitats to conventional agricultural regions and recently to large areas of genetically engineered (ge) croplands. this ge revolution occurred for cotton in a span of slightly more than a decade during which a switch occurred in major cotton production areas from growing 100% conventional cotton to an environment in which 95% transgenics are grown. ecological interactions between ge targeted insects and other insect ...200818536245
attachment of ampicillin to expanded poly(tetrafluoroethylene): surface reactions leading to inhibition of microbial growth.the broad spectrum antibiotic, ampicillin (am), was reacted to expanded poly (tetrafluoroethylene) (eptfe) surfaces and resulted in the formation of antimicrobial surfaces effective against gram-positive, staphylococcus aureus, bacillus thuringiensis, and enterococcus faecalis, and gram-negative, escherichia coli, pseudomonas putida, and salmonella enterica bacteria. these eptfe surface modifications were accomplished by utilization of microwave maleic anhydride (ma) plasma reactions leading to ...200818540673
a bacillus thuringiensis strain producing a polyglutamate capsule resembling that of bacillus anthracis.bacillus thuringiensis serovar monterrey strain bgsc 4aj1 produced a microscopically visible capsule that reacted with a fluorescent antibody specific for the poly-gamma-d-glutamic acid (pga) capsule of bacillus anthracis. pga capsule biosynthesis genes with 75%, 81%, 72%, 65% and 63% similarity, respectively, to those of the b. anthracis capbcade cluster were present on a plasmid (paj1-1). strain bgsc 4aj1, together with five strains of bacillus cereus that hybridized to a pga cap gene probe, w ...200818549401
outcrossed cottonseed and adventitious bt plants in arizona refuges.outcrossing of non-bt cotton (gossypium hirsutum (l.)) in refuges by transgenic bt cultivars could reduce the efficacy of refuges for delaying resistance in seed-feeding pests. based on reports that outcrossing decreased as distance from bt cotton increased in small-scale studies, we hypothesized that increasing refuge width or distance from bt fields would reduce outcrossing. in a large-scale study in arizona, we quantified bt seed in refuges of experimental and commercial fields, comparing out ...200818549770
diversity of aminopeptidases, derived from four lepidopteran gene duplications, and polycalins expressed in the midgut of helicoverpa armigera: identification of proteins binding the delta-endotoxin, cry1ac of bacillus thuringiensis.helicoverpa armigera midgut proteins that bind the bacillus thuringiensis (bt) delta-endotoxin cry1ac were purified by affinity chromatography. sds-page showed that several proteins were eluted with n-acetylgalactosamine and no further proteins were detected after elution with urea. tandem mass spectral data for tryptic peptides initially indicated that the proteins resembled aminopeptidases (apns) from other lepidopterans and cdna sequences for seven apns were isolated from h. armigera through ...200818549954
production of an insecticidal crystal protein from bacillus thuringiensis by the methylotroph methylobacterium extorquens.the cry1aa protein from bacillus thuringiensis is an insecticidal protein that is highly active against several species of lepidoptera. we cloned and expressed the cry1aa gene in a plant-colonizing methylotroph, methylobacterium extorquens, under the control of the strong m. extorquens am1 methanol dehydrogenase promoter, p(mxaf). transmission electron microscopy revealed characteristic bipyramidal intracellular delta-endotoxin crystals similar to the crystalline inclusions formed by b. thuringi ...200818552184
toxicological assessment of pollen from different bt rice lines on bombyx mori (lepidoptera: bombyxidae).the relative toxicity of bt rice pollen to domestic silkworm, bombyx mori linnaeus (lepidoptera: bombycidae), was assessed by a leaf-dip bioassay under laboratory conditions. silkworm first instars were sensitive to pollen from bt rice lines, b1 and kmd1, but were not sensitive to pollen from bt rice line tt9-3. first instars were 1.34-2.12 times more sensitive to b1 pollen than older instars. bioassays of subacute toxicity under a worst-case scenario suggested that continuous exposure to a subl ...200818559190
assessing the risk to nontarget organisms from bt corn resistant to corn rootworms (coleoptera: chrysomelidae): tier-i testing with orius insidiosus (heteroptera: anthocoridae).a 14-d continuous dietary exposure bioassay using nymphs of the insidious flower bug, orius insidiosus (say) (heteroptera: anthocoridae), was conducted to assess nontarget impacts of genetically modified corn event mon 863 expressing the cry3bb1 protein for management of corn rootworms, diabrotica spp. (coleoptera: chrysomelidae). nymphs of o. insidiosus were continuously fed a bee pollen diet inoculated with a maximum hazard exposure dose (930 microg/g of diet) of the cry3bb1 protein for 14 d. ...200818559191
nematode resistance.plant-parasitic nematodes are major pests of both temperate and tropical agriculture. many of the most damaging species employ an advanced parasitic strategy in which they induce redifferentiation of root cells to form specialized feeding structures able to support nematode growth and reproduction over several weeks. current control measures, particularly in intensive agriculture systems, rely heavily on nematicides but alternative strategies are required as effective chemicals are withdrawn fro ...200818564304
selective cytotoxic activity against leukemic cell lines from mosquitocidal bacillus thuringiensis parasporal inclusions.the discovery of parasporin has triggered an interest in examining various bacillus thuringiensis (bt) isolates for specific anti-cancer activity. the aim of this study was to determine the potency and specificity of parasporal inclusions from malaysian mosquitocidal bt isolates against a leukemic cell line (cem-ss). the bt isolates used in this study were identified as having weak to potent larvicidal activity against aedes aegypti and varying hemolytic activity. the 12 mosquitocidal bt isolate ...200818564708
histology and ultrastructure of aedes albopictus larval midgut infected with bacillus thuringiensis var. israelensis.histological and ultrastrucutural alterations in the midgut of aedes albopictus larvae infected with bacillus thuringiensis var. israelensis (bti) were observed by light and transmission electron microscopy (tem). two formulations of bti were used: granulated and powder, with 0.2% active ingredient in 90 larvae of ae. albopictus distributed in three containers containing 30 larvae each (one control group and two test groups). the midgut epithelium of the control group presented flattened and elo ...200818567013
high-resolution crystal structure of activated cyt2ba monomer from bacillus thuringiensis subsp. israelensis.the cyt family of proteins consists of delta-endotoxins expressed during sporulation of several subspecies of bacillus thuringiensis. its members possess insecticidal, hemolytic, and cytolytic activities through pore formation and attract attention due to their potential use as vehicles for targeted membrane destruction. the delta-endotoxins of subsp. israelensis include three cyt species: a major cyt1aa and two minor proteins, cyt2ba and cyt1ca. a cleaved cyt protein that lacks the n- and c-ter ...200818571667
forensic analysis of bioagents by x-ray and tof-sims hyperspectral imaging.hyperspectral imaging combined with multivariate statistics is an approach to microanalysis that makes the maximum use of the large amount of data potentially collected in forensics analysis. this study examines the efficacy of using hyperspectral imaging-enabled microscopies to identify chemical signatures in simulated bioagent materials. this approach allowed for the ready discrimination between all samples in the test. in particular, the hyperspectral imaging approach allowed for the identifi ...200818571885
landscape refuges delay resistance of the european corn borer to bt-maize: a demo-genetic dynamic model.we constructed a reaction-diffusion model of the development of resistance to transgenic insecticidal bt crops in pest populations. kostitzin's demo-genetic model describes local interactions between three competing pest genotypes with alleles conferring resistance or susceptibility to transgenic plants, the spatial spread of insects being modelled by diffusion. this new approach makes it possible to combine a spatial demographic model of population dynamics with classical genetic theory. we use ...200818572213
monitoring a genetically modified pseudomonas sp. released on pine leaves reveals concerted successional patterns of the bacterial phyllospheric community.the fate of a biocontrol agent released on pine phyllosphere in a greenhouse-confined trial was followed over 102 days. the microorganism used, a pseudomonas sp., isolated from pinus nigra, carries the cry9a toxin gene from bacillus thuringiensis. in order to detect the gmm, specific primers were used, and a previously defined protocol for dna isolation from bacteria colonizing pine needles was applied. the method, based on vortexing in a suspension of glass beads followed by microcolumn extract ...200818574707
imaging and 3d elemental characterization of intact bacterial spores by high-resolution secondary ion mass spectrometry.we present a quantitative, imaging technique based on nanometer-scale secondary ion mass spectrometry for mapping the 3d elemental distribution present in an individual micrometer-sized bacillus spore. we use depth profile analysis to access the 3d compositional information of an intact spore without the additional sample preparation steps (fixation, embedding, and sectioning) typically used to access substructural information in biological samples. the method is designed to ensure sample integr ...200818578543
susceptibility of manduca sexta to cry1ab toxin of bacillus thuringiensis correlates directly to developmental expression of the cadherin receptor bt-r(1).the cadherin receptor bt-r(1), localized in the midgut epithelium of the tobacco hornworm, manduca sexta, is coupled to programmed oncotic-like cell death, which is triggered by the univalent binding of the cry1ab toxin of bacillus thuringiensis (bt) to the receptor. kinetic analysis of bt-r(1) expression during larval development reveals that the density of bt-r(1) on the midgut surface increases dramatically along with an equivalent rise in the concentration of cry1ab toxin molecules needed to ...200818582591
production of concentrates of bacterial bio-insecticide bacillus thuringiensis var. israelensis by flocculation/sedimentation.flocculation/sedimentation of bacillus thuringiensis var. israelensis (bti) using flocculating agents has been studied. batch cell production was performed in an agitated tank, and the flocculation assays were carried out in jar tests. flocculent suspensions were characterized based on diameter of flocs and density. the best results were obtained with cacl(2).2h(2)o, fecl(3).6h(2)o, al(2)(so(4))(3) and tannin, with optimal flocculation concentrations of 2500, 2500, 3500 and 1000 mg l(-1), respec ...200818582843
purification of vip3aa from bacillus thuringiensis hd-1 and its contribution to toxicity of hd-1 to spruce budworm (choristoneura fumiferana) and gypsy moth (lymantria dispar) (lepidoptera).we developed a protocol for obtaining high yields (10-15 mg per 1100 ml of culture supernatant) of highly purified (up to 95%) vip3aa protein from hd-1 cultures. the protocol is based on acetone precipitation of supernatant protein, followed by hplc fractionation (deae-5pw column) and several concentration steps. our protocol resulted in higher yields and purity of vip3aa than a previously published method [estruch, j.j., warren, g.w., mullins, m.a., nye, g.j., craig, j.a., koziel, m.g., 1996. v ...200818585733
sequence diversity of bacillus thuringiensis flagellin (h antigen) protein at the intra-h serotype level.in bacillus thuringiensis, the hag gene encodes flagellin, the protein responsible for eliciting the immunological reaction in h serotyping. specific flagellin amino acid sequences have been correlated to specific b. thuringiensis h serotypes, h1 to h67. ten h serotypes, however, contain three or more antigenic subfactors, labeled a, b, c, d, or e, and have been subdivided into 23 serovars. in the present study, we set out to analyze the sequence diversity of flagellins among serovars from the s ...200818586969
survey of group i and group ii introns in 29 sequenced genomes of the bacillus cereus group: insights into their spread and evolution.group i and group ii introns are different catalytic self-splicing and mobile rna elements that contribute to genome dynamics. in this study, we have analyzed their distribution and evolution in 29 sequenced genomes from the bacillus cereus group of bacteria. introns were of different structural classes and evolutionary origins, and a large number of nearly identical elements are shared between multiple strains of different sources, suggesting recent lateral transfers and/or that introns are und ...200818587153
[cloning, prokaryotic expression and functional analysis of pep gene from bacillus thuringiensis lysogenic bacteriophage].random outbreak of lysogenic bacteriophage from bacillus thuringiensis was very harmful to the production of bacillus thuringiensis insecticide. we clarified the background of the phage from bacillus thuringiensis mz1 at the molecular level to solve the problem of random outbreak.200818590230
intergeneric coaggregation of strains isolated from phenol-degrading aerobic granules.this work aims at exploring the intergeneric coaggregation of the pairs of strains, acinetobacter calcoaceticus i6 and bacillus thuringiensis i2 or candida tropicalis i9 (with genbank accession numbers eu250016, eu036759, and dq515822) isolated from phenol-degrading aerobic granules. the i2 and i6 are functionally similar stains, while the i6 and i9 are functionally dissimilar strains. the lectin-saccharide interaction controlled the coaggregation of both the i2+i6 and i6+i9 pairs, with the prot ...200818414847
expression of a bacillus thuringiensis toxin (cry1ab) gene in cabbage (brassica oleracea l. var. capitata l.) chloroplasts confers high insecticidal efficacy against plutella xylostella.chloroplast genetic engineering is an environmentally friendly approach, where the foreign integrated gene is often expressed at a higher level than nuclear transformation. the cry1ab gene was successfully transferred into the cabbage chloroplast genome in this study. the aada and cry1ab genes were inserted into the pascc201 vector and driven by the prrn promoter. the cabbage-specific plastid vectors were transferred into the chloroplasts of cabbage via particle gun mediated transformation. rege ...200818415072
[use of bentonite in production of granular bioinsecticide on the basis of bacillus thuringiensis].electrokinetic properties of bacillus thuringiensis spores and peculiarities of their interaction with clayey minerals montmorillonite and paligorskite were investigated. existence of contact interaction between montmorillonite particles and bacteria endospores was shown. granular bioinsecticide was prepared on the basis of bentonite, montmorillonite being its main component. it was discovered that the preparation can be well preserved for 3 months. while using the preparation after the long-ter ...200818416152
[aedes albopictus, vector of chikungunya and dengue viruses in reunion island: biology and control].chikungunya virus (chikv) and dengue virus (denv) are mosquito-borne viruses transmitted by the aedes genus. dengue is considered as the most important arbovirus disease throughout the world. chikungunya, known from epidemics in continental africa and asia, has up to now been poorly studied. it has been recently responsible for the severe 2004-2007 epidemic reported in the indian ocean (io), which has caused several serious health and economic problems. this unprecedented epidemic of the io has ...200818416242
larval feeding on bt hybrid and non-bt corn seedlings by harmonia axyridis (coleoptera: coccinellidae) and coleomegilla maculata (coleoptera: coccinellidae).zoophytophagy is an omnivorous activity that occurs when a primarily carnivorous species feeds on plant material. plant feeding by beneficial predators may have negative consequences if the plant material has been chemically treated, contains toxins, or was transgenically altered. although common in predaceous hemiptera, zoophytophagy has been rarely studied in aphidophagous coccinellids. this study examined the likelihood of feeding on bt and non-bt corn seedlings by third- and fourth-instar co ...200818419926
from soil to gut: bacillus cereus and its food poisoning toxins.bacillus cereus is widespread in nature and frequently isolated from soil and growing plants, but it is also well adapted for growth in the intestinal tract of insects and mammals. from these habitats it is easily spread to foods, where it may cause an emetic or a diarrhoeal type of food-associated illness that is becoming increasingly important in the industrialized world. the emetic disease is a food intoxication caused by cereulide, a small ring-formed dodecadepsipeptide. similar to the virul ...200818422617
study of the irreversible binding of bacillus thuringiensis cry1aa to brush border membrane vesicles from bombyx mori midgut.the binding of bacillus thuringiensis delta-endotoxin to brush border membrane vesicles (bbmvs) from the target insect larval midgut comprises with not only a reversible but also an irreversible component. the irreversible binding of delta-endotoxin is thought to be a pathologically important factor. here, we studied the irreversible binding of cry1aa to the bbmvs of bombyx mori. the (125)i-labeled cry1aa bound to the solubilized brush border membrane (bbm) through rapid dissociation only, unlik ...200818433767
characterization of bacillus thuringiensis strain dor4 toxic to castor semilooper achaea janata: proteolytic processing and binding of toxins to receptors.we have isolated a strain of bacillus thuringiensis (bt) from indian soil samples that was shown to be toxic to achaea janata larvae. the isolate, named b. thuringiensis dor4, serotypically identified with the standard subspecies kurstaki (h3a3b3c) and produced bipyramidal inclusions along with an amorphous type. although the plasmid pattern of dor4 was different from that of the reference strain, a crystal protein profile showed the presence of two major bands (130 and 65 kda) similar to those ...200818437459
phagocytic activity and encapsulation rate of galleria mellonella larval haemocytes during bacterial infection by bacillus thuringiensis.the bacterium bacillus thuringiensis (bt) is a pathogen of many insect species and is actively used in biocontrol. after the peroral inoculation of galleria mellonella by the bt in 5% sublethal concentration (lc(5)), a 1.5-fold increase in the phagocytic activity of infected larvae has been registered on the second and third days after the inoculation. with the increase of bt-inoculum amount to 15% of sublethal concentration (lc(15)), a further increase of the phagocytic activity and enhanced en ...200818440019
a nonribosomal peptide synthetase gene tzw1 is involved in zwittermicin a biosynthesis in bacillus thuringiensis g03.a 4.20-kb sspi fragment from bacillus thuringiensis g03 was cloned and sequenced. sequencing analysis revealed two complete open reading frames (orf; tzw1 and tzw2), and one incomplete orf (tzw3) (genbank accession no. eu293887). tzw1 encodes a putative nonribosomal peptide synthetase with thiolation and condensation domains localized at the c-termini, whereas tzw2 and tzw3 encode acyl carrier protein and acyl-coa dehydrogenase, respectively. to investigate the function of tzw1 in zwittermicin a ...200818446411
aspergillus flavus aflatoxin occurrence and expression of aflatoxin biosynthesis genes in soil.the carcinogen aflatoxin b1 (afb1) produced by aspergillus flavus is a major food safety concern in crops. however, information on afb1 occurrence in soil and crop residue is scarce. a series of experiments investigated the occurrence of afb1 in soil and corn residues and ascertained the ecology of a. flavus in a dundee silt loam soil. samples of untilled soil (0-2 cm) and residues were collected in march 2007 from plots previously planted with a corn isoline containing the bacillus thuringiensi ...200818449222
effects of metabolic inhibitors on activity of cry1ab toxin to inhibit growth of ephestia kuehniella larvae.although the toxins of bacillus thuringiensis berliner (bt) are frequently used to control lepidopteran pests, the tolerance or resistance of some lepidopteran moth strains may limit bt applications. in this study, insecticidal cocktails consisting of sublethal doses of cry1ab toxin and additive compounds were tested for their suppressive effect on larval relative growth rate (rgr) in ephestia kuehniella zeller under laboratory conditions.200818449852
the role of a purine-specific nucleoside hydrolase in spore germination of bacillus thuringiensis.a homologous gene (iunh) of a putative nucleoside hydrolase (nh), which had been identified from the exosporia of bacillus cereus and bacillus anthracis spores, was cloned from bacillus thuringiensis subsp. kurstaki. disruption of iunh did not affect the vegetative growth and sporulation of bacillus thuringiensis, but promoted both inosine- and adenosine-induced spore germination. the inosine- or adenosine-induced germination rate decreased when the wild-type iunh gene was overexpressed in bacil ...200818451042
the members of the bacillus cereus group are commonly present contaminants of fresh and heat-treated milk.to determine the level of milk contamination by bacillus cereus sensu lato, 44 samples were collected from a dairy farm and two independent dairies in northeastern poland. a total of 680 b. cereus sensu lato isolates were recovered. based on spore counts, their highest level in milk was found during the spring and summer months. although significant variations in chromosomal dna polymorphisms among b. cereus sensu lato isolates were noted based on repetitive element sequence polymorphism (rep-pc ...200818456114
characterization of a novel cry9bb delta-endotoxin from bacillus thuringiensis.the brazilian bacillus thuringiensis serovar japonensis strain s725 was selected for its toxicity to the velvetbean caterpillar, anticarsia gemmatalis. this strain produces spherical crystals harbouring a major protein of about 130 kda which yields fragments of between 50 and 70 kda upon trypsin activation. the protein showed a high level of identity and immunoafinity to the cry9 class of delta-endotoxins. the cloned cry9-like gene sequence contains a 3492 bp orf, which encodes a polypeptide of ...200818456277
display of avian influenza virus nucleoprotein on bacillus thuringiensis cell surface using ctc as a fusion partner.the s-layer protein ctc surface display system of bacillus thuringiensis was used to test the possibility of displaying avian influenza virus nucleoprotein (np) on the cell surface of b. thuringiensis. by fusing np with the anchoring motif of ctc, four recombinant plasmids were constructed. they harbored fusion gene ctc-np, csa-ctc-np (csa representing csaab operon, very important in anchoring s-layer protein on cell surface), ctc-npp (npp representing the part fragment of np), and csa-ctc-npp, ...200818236038
protected by fumigants: beetle perfumes in antimicrobial defense.beetles share with other eukaryotes an innate immune system that mediates endogenous defense against pathogens. in addition, larvae of some taxa produce fluid exocrine secretions that contain antimicrobial compounds. in this paper, we provide evidence that larvae of the brassy willow leaf beetle phratora vitellinae constitutively release volatile glandular secretions that combat pathogens in their microenvironment. we identified salicylaldehyde as the major component of their enveloping perfume ...200818236110
leaf surface factors of transgenic bt cotton associated with the feeding behaviors of cotton aphids: a case study on non-target effects.the present paper reports case study results of the risk assessment of transgenic bt cotton on a non-target pest, cotton aphid, aphis gossypii. several types of techniques, i.e., electrical penetration graph (epg), light and electron microscopy, bioassays and chemical analysis, were applied to investigate physical and chemical leaf factors of 2 transgenic bt cotton lines (gk12 and gk19) and their parental non-bt cotton line (simian3) associated with searching and feeding behaviors of cotton aphi ...200818239893
deletion of dnan1 generates a mutator phenotype in bacillus anthracis.the dnan gene in eubacteria is an essential gene that encodes the beta subunit of replicative dna polymerase. nearly all eubacterial genomes sequenced to date predict a single copy of the dnan gene in a well-conserved neighboring gene context. however, 19 genomes out of 348 scanned, including bacillus anthracis, bacillus cereus, bacillus thuringiensis, and bacillus weihenstephanensis, predict more than one dnan gene. in most cases, these genomes appear to maintain a copy of the dnan homolog in i ...200818242150
displaying the protein of mycoplasma gallisepticum agglutinin on the cell surface of bacillus thuringiensis with the s-layer protein.the s-layer protein ctc surface-display system of bacillus thuringiensis (bt) was used to test the possibility of displaying the protein of mycoplasma gallisepticum (mg) agglutinin (pmga) on the bt cell surface. by fusing part of pmga1.2 (pmga1.2p) with the surface-anchoring motif of ctc, two recombinant plasmids, pctc-pmga1.2p and pcspmga1.2p, were constructed. they harboured the fusion genes ctc-pmga1.2p and csa-ctc-pmga1.2p (csa represents csaab operon, important in anchoring the s-layer prot ...200818243589
recombinant cry1ia protein is highly toxic to cotton boll weevil (anthonomus grandis boheman) and fall armyworm (spodoptera frugiperda).to evaluate the activity of cry1ia gene against cotton pests, spodoptera frugiperda and anthonomus grandis.200818248369
cloning and characterization of a novel cry1a toxin from bacillus thuringiensis with high toxicity to the asian corn borer and other lepidopteran insects.a novel cry1a was cloned from bacillus thuringiensis strain bt8 and expressed in the b. thuringiensis acrystalliferous mutant hd73(-). the gene, designated cry1ah1, encoded a protein with a molecular weight of 134 kda. reverse transcriptase-pcr and western blotting showed that cry1ah was expressed in the host strain bt8. the toxin expressed in hd73(-) exhibited high toxicity against lepidopteran larvae of ostrinia furnacalis, helicoverpa armigera, chilo suppressalis, and plutella xylostella. the ...200818248430
positive association between resistance to bacillus thuringiensis and overwintering survival of cabbage loopers, trichoplusia ni (lepidoptera: noctuidae).development of resistance to insecticides has generally been associated with fitness costs that may be magnified under challenging conditions. lepidopterans which are resistant to the biopesticide bacillus thuringiensis subsp. kurstaki (btk) have been shown to have reduced fitness, such as lower survival when subjected to overwintering stress. recently, resistance to btk has been found in some populations of trichoplusia ni hübner in greenhouses in british columbia. this situation provides an op ...200818257958
insect resistance to bt crops: evidence versus theory.evolution of insect resistance threatens the continued success of transgenic crops producing bacillus thuringiensis (bt) toxins that kill pests. the approach used most widely to delay insect resistance to bt crops is the refuge strategy, which requires refuges of host plants without bt toxins near bt crops to promote survival of susceptible pests. however, large-scale tests of the refuge strategy have been problematic. analysis of more than a decade of global monitoring data reveals that the fre ...200818259177
improving the insecticidal activity by expression of a recombinant cry1ac gene with chitinase-encoding gene in acrystalliferous bacillus thuringiensis.in order to improve the insecticidal activity, the chitinase gene from tobacco (nicotiana tabacum) endochitinase and the cry1ac gene from bacillus thuringiensis were cloned into the vector pht315 and designated as phuaccb5 plasmid. the constructed transcriptional fusion was attempted under the control of the native cry1ac promoter. plasmid phuaccb5 was introduced into b. thuringiensis acrystalliferous by electroporation. analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and w ...200818259812
expression and characterization of aiia gene from bacillus subtilis bs-1.ahl-lactonase (aiia), a metallo-beta-lactamase produced by bacillus thuringiensis, bacillus cereus and bacillus anthracis, specifically hydrolyzes n-acyl-homoserine lactones (ahls) secreted by gram-negative bacteria and thereby attenuates the symptoms caused by plant pathogens. in this study, an aiia gene was cloned from bacillus subtilis bs-1 by pcr with a pair of degenerate primers. the deduced 250 amino acid sequence contained two small conserved regions, 103shlhfdh109 and 166tpghtpgh173, whi ...200818261893
expression of mel gene improves the uv resistance of bacillus thuringiensis.to improve ultraviolet (uv) resistance of bacillus thuringiensis for increasing the duration of the bt product applied in the field, a genetically engineered strain bt td841 that produced both melanin and cry1a protein was constructed, and its uv resistance was evaluated in the laboratory.200818266703
detection of large plasmids from the bacillus cereus group.the members of the bacillus cereus group, bacillus anthracis, bacillus thuringiensis, and b. cereus senso stricto, are largely defined by their content of large plasmids, which encode major virulence factors. here we offer an easy, fast, and reliable protocol for the isolation and detection of large plasmids up to the size of at least 350kb. furthermore, using this method, we report that bacillus mycoides contain large plasmids.200818179822
mineralization of the bacillus thuringiensis cry1ac endotoxin in soil.although a number of studies have been done describing the fate of bacillus thuringiensis insecticidal endotoxins in soil, there is conflicting information on the persistence of this class of insecticidal toxins. this is partly due to methodological limitations in many of the previous studies. in the experiments reported here, 14c-labeled b. thuringiensis cry1ac endotoxin was used to study its mineralization in soil incubated under controlled conditions. fifty-nine percent of the radiolabeled cr ...200818181567
a meta-analysis of effects of bt crops on honey bees (hymenoptera: apidae).honey bees (apis mellifera l.) are the most important pollinators of many agricultural crops worldwide and are a key test species used in the tiered safety assessment of genetically engineered insect-resistant crops. there is concern that widespread planting of these transgenic crops could harm honey bee populations.200818183296
binding properties of a monoclonal antibody against the cry1ab from bacillus thuringensis for the development of a capillary electrophoresis competitive immunoassay.experimental work performed was aimed at the assessment of a competitive capillary electrophoresis immunoassay with laser-induced fluorescence (ceia-lif) detection for the determination of the cry1ab endotoxin from bacillus thuringensis. the binding constant of a monoclonal antibody, raised against the insecticide protein cry1ab, was determined on a microplate by indirect enzyme-linked immunosorbent assay (elisa) and compared with that obtained in-capillary under nonequilibrium separation condit ...200818185920
suppression of dengue transmission by application of integrated vector control strategies at sero-positive gis-based foci.a serological survey of primary school children from six schools in chachoengsao province, thailand, was performed at the end of the peak of dengue transmission. gis analysis of sero-positive cases was carried out to determine transmission foci. vector control implementation was conducted in the foci and also within 100 meters around the foci in the treated areas by community participation in collaboration with the local government. vector control strategies included source reduction together wi ...200818187787
bombyx mori midgut membrane protein p252, which binds to bacillus thuringiensis cry1a, is a chlorophyllide-binding protein, and the resulting complex has antimicrobial activity.the epithelial cell membrane 252-kda protein (p252) isolated in our laboratory from bombyx mori midgut was shown to bind strongly with cry1aa, cry1ab, and cry1ac toxins of bacillus thuringiensis (15). in the current paper, p252 was shown to bind with chlorophyllide (chlide) to form red fluorescent protein (rfp) complex, termed bm252rfp, with absorbance and fluorescence emission peaks at 600 nm and 620 nm, respectively. p252 at a concentration of 1 microm is shown to bind with about 50 microm chl ...200818192432
self-transfer and mobilisation capabilities of the pxo2-like plasmid pbt9727 from bacillus thuringiensis subsp. konkukian 97-27.recent characterisations of plasmids related to the anthrax virulence plasmids pxo1 and pxo2 in clinical isolates of bacillus cereus and bacillus thuringiensis have contributed to the emerging picture of a virulence-associated plasmid pool in the b. cereus sensu lato group. the family of pxo2-like plasmids includes the conjugative plasmid paw63 from the biopesticide strain b. thuringiensis subsp. kurstaki hd73 and the heretofore cryptic plasmid pbt9727 from the clinical strain b. thuringiensis s ...200818272219
performance of laying hens fed diets containing das-59122-7 maize grain compared with diets containing nontransgenic maize grain.an experiment using 216 hy-line w-36 pullets was conducted to evaluate transgenic maize grain containing the cry34ab1 and cry35ab1 genes from a bacillus thuringiensis (bt) strain and the phosphinothricin ace-tyltransferase (pat) gene from streptomyces viridochromogenes. expression of the cry34ab1 and cry35ab1 genes confers resistance to corn rootworms, and the pat gene confers tolerance to herbicides containing glufosinate-ammonium. pullets (20 wk of age) were placed in cage lots (3 hens/cage, 2 ...200818281573
wet and dry density of bacillus anthracis and other bacillus species.to determine the wet and dry density of spores of bacillus anthracis and compare these values with the densities of other bacillus species grown and sporulated under similar conditions.200818298528
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