Publications
Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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self-transfer and mobilisation capabilities of the pxo2-like plasmid pbt9727 from bacillus thuringiensis subsp. konkukian 97-27. | recent characterisations of plasmids related to the anthrax virulence plasmids pxo1 and pxo2 in clinical isolates of bacillus cereus and bacillus thuringiensis have contributed to the emerging picture of a virulence-associated plasmid pool in the b. cereus sensu lato group. the family of pxo2-like plasmids includes the conjugative plasmid paw63 from the biopesticide strain b. thuringiensis subsp. kurstaki hd73 and the heretofore cryptic plasmid pbt9727 from the clinical strain b. thuringiensis s ... | 2008 | 18272219 |
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 ... | 2008 | 18281573 |
glycosyltransferase: a specific marker for the discrimination of bacillus anthracis from the bacillus cereus group. | bacillus anthracis, the aetiological agent of anthrax, has been taxonomically classified with the bacillus cereus group, which comprises b. cereus, bacillus thuringiensis, bacillus mycoides, bacillus pseudomycoides and bacillus weihenstephanensis. although the pathogenesis and ecological manifestations may be different, b. anthracis shares a high degree of dna sequence similarity with its group member species. as a result, the discrimination of b. anthracis from its close relatives in the b. cer ... | 2008 | 18287289 |
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. | 2008 | 18179822 |
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 ... | 2008 | 18181567 |
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. | 2008 | 18183296 |
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 ... | 2008 | 18185920 |
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 ... | 2008 | 18187787 |
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 ... | 2008 | 18192432 |
wet and dry density of bacillus anthracis and other bacillus species. | to determine the wet and dry density of spores of bacillus anthracis and compare these values with the densities of other bacillus species grown and sporulated under similar conditions. | 2008 | 18298528 |
phenotypic and genotypic features of new autoagglutinating bacillus thuringiensis strains. | a total of 28 autoagglutinating strains of bacillus thuringiensis were isolated from different ecologic niches and distinct sites. twenty-six strains demonstrated toxicity to mosquito larvae of aedes aegypti and culex quinquefasciatus. the electrophoretic protein profiles of the crystal components were studied. twenty-three out of the 28 strains showed the same larvicidal activity and the same protein profiles as b. thuringiensis serovar israelensis. using isoenzyme analysis (mlee), it was obser ... | 2008 | 18304571 |
etest for antibiotic susceptibility testing of bacillus anthracis, bacillus cereus and bacillus thuringiensis: evaluation of a french collection. | 2008 | 18316178 | |
biotechnological prospects for engineering insect-resistant plants. | 2008 | 18316644 | |
expression of a synthetic cry1ec gene for resistance against spodoptera litura in transgenic peanut (arachis hypogaea l.). | the tobacco cutworm (spodoptera litura) is a polyphagous foliage insect and a major pest on peanut (arachis hypogaea l.). s. litura is susceptible to the chimeric delta-endotoxin cry1ec reported earlier. de-embryonated cotyledon explants of peanut were transformed using agrobacterium tumefaciens strain eha101 harboring a synthetic cry1ec gene driven by the camv 35s promoter. transgenic plants of peanut with a single copy insertion of cry1ec were selected in the t(0) generation by southern blot h ... | 2008 | 18320194 |
prey mediated effects of bt maize on fitness and digestive physiology of the red spider mite predator stethorus punctillum weise (coleoptera: coccinellidae). | the present study investigated prey-mediated effects of two maize varieties expressing a truncated cry1ab, compa cb (event bt176) and dkc7565 (event mon810), on the biology of the ladybird stethorus punctillum. although immuno-assays demonstrated the presence of cry1ab in both prey and predator collected from commercial maize-growing fields, neither transgenic variety had any negative effects on survival of the predator, nor on the developmental time through to adulthood. furthermore, no subsequ ... | 2008 | 18322817 |
impact of bacillus thuringiensis toxin cry1ab on rumen epithelial cells (rec) - a new in vitro model for safety assessment of recombinant food compounds. | the growing use of genetically modified crops necessitates viable screening methods for safety evaluation of recombinant feed, particularly for ruminants. a new sheep rumen epithelial cell culture is introduced as an in vitro cell system for safety evaluation especially focussing on feed and food compounds. we used lactate dehydrogenase (ldh) release, wst-1 conversion, atp content and caspase 3/7 activity to evaluate cytotoxicity of cry1ab, one of the newly expressed bt-proteins in transgene mai ... | 2008 | 18325653 |
cysteine scanning mutagenesis of alpha4, a putative pore-lining helix of the bacillus thuringiensis insecticidal toxin cry1aa. | helix alpha4 of bacillus thuringiensis cry toxins is thought to line the lumen of the pores they form in the midgut epithelial cells of susceptible insect larvae. to define its functional role in pore formation, most of the alpha4 amino acid residues were replaced individually by a cysteine in the cry1aa toxin. the toxicities and pore-forming abilities of the mutated toxins were examined, respectively, by bioassays using neonate manduca sexta larvae and by a light-scattering assay using midgut b ... | 2008 | 18326669 |
benzylideneacetone, an immunosuppressant, enhances virulence of bacillus thuringiensis against beet armyworm (lepidoptera: noctuidae). | benzylideneacetone (bza) is a metabolite of gram-negative entomopathogenic bacterium xenorhabdus nematophila, and it acts as an enzyme inhibitor against phospholipase a2 (pla2). pla2 catalyzes a committed biosynthetic step of eicosanoids, which mediate insect immune reactions to infection by microbial pathogens. this study tested a hypothesis that a putative immunosuppressive activity of bza may enhance virulence of bacillus thuringiensis against the fifth instars of spodoptera exigua (hübner) ( ... | 2008 | 18330113 |
baseline susceptibility of tobacco budworm (lepidoptera: noctuidae) to cry1f toxin from bacillus thuringiensis. | transgenic cotton, gossypium hirsutum l., lines expressing both cry1f and cry1ac insecticidal proteins from bacillus thuringiensis (bt) have been commercially available in the united states since 2005. both bt proteins are highly effective against tobacco budworm, heliothis virescens (f.), and other lepidopteran pests of cotton. although crylac has been available in bt cotton since 1996, the cry1f component is relatively new. as part of the proactive resistance management program for cry1f/cry1a ... | 2008 | 18330132 |
effect of transgenic bacillus thuringiensis rice lines on mortality and feeding behavior of rice stem borers (lepidoptera: crambidae). | ten transgenic bacillus thuringiensis bt rice, oryza sativa l., lines with different bt genes (two cry1ac lines, three cry2a lines, and five cry9c lines) derived from the same variety minghui 63 were evaluated in both the laboratory and the field. bioassays were conducted by using the first instars of two main rice lepidopteran insect species: yellow stem borer, scirpophaga incertulas (walker) and asiatic rice borer, chilo suppressalis (walker). all transgenic lines exhibited high toxicity to th ... | 2008 | 18330134 |
aquatic fate and effects of bacillus thuringiensis cry3bb1 protein: toward risk assessment. | genetically engineered crops expressing bacillus thuringiensis (bt) insecticidal crystalline (cry) proteins became commercially available in the united states in 1996. in 2006, 19 million ha of bt corn were planted worldwide, which represents a 10 million ha increase in 10 years. the sustainability of bt crops is important, because their use has significantly reduced the amount of chemical insecticides necessary to control agricultural pests. despite the high adoption rates of this novel insecti ... | 2008 | 18333682 |
a naturally occurring plant cysteine protease possesses remarkable toxicity against insect pests and synergizes bacillus thuringiensis toxin. | when caterpillars feed on maize (zea maize l.) lines with native resistance to several lepidopteran pests, a defensive cysteine protease, mir1-cp, rapidly accumulates at the wound site. mir1-cp has been shown to inhibit caterpillar growth in vivo by attacking and permeabilizing the insect's peritrophic matrix (pm), a structure that surrounds the food bolus, assists in digestion and protects the midgut from microbes and toxins. pm permeabilization weakens the caterpillar defenses by facilitating ... | 2008 | 18335057 |
quantifying the reproduction of bacillus thuringiensis hd1 in cadavers and live larvae of plutella xylostella. | the bacillus cereus group comprises a range of micro-organisms with diverse habits, including gut commensals, opportunistic pathogens and soil saprophytes. using quantitative microbiological methods we tested whether bacillus thuringiensis (bt) could reproduce in cadavers of plutella xylostella killed by bt, or in the gut of live insects, or be transmitted vertically from females to their offspring. we also tested whether diverse bt strains could grow in high nutrient broth at a ph similar to th ... | 2008 | 18336832 |
denaturing gradient gel electrophoresis analysis of bacterial community profiles in the rhizosphere of cry1ac-carrying brassica rapa subsp. pekinensis. | the effect of genetically modified (gm) brassica rapa subsp. pekinensis (chinese cabbage) expressing bt toxin gene (cry1ac) to the rhizosphere bacterial community was examined using the denaturing gradient gel electrophoresis (dgge) fingerprinting method. from the visual comparison of the dgge profiles, there were no significant differences between the profiles of bt and control rhizosphere in both suwon and yesan samples. from the sequence analysis of the individual bands, sphingomonas sp. of a ... | 2008 | 18337686 |
[cloning and physical map construction of a large plasmid pbmb165 in bacillus thuringiensis]. | the largest detected plasmid pbmb165 from bacillus thuringiensis subsp. tenebrionis strain ybt-1765 (h(8ab)) was cloned and its physical map was analyzed. for the cloning, two bac libraries were constructed with their plasmid dna and genomic dna, respectively. the plasmid dna bac library was obtained by partially digesting plasmid dna with bamhi and then cloning to pbelobac11 vector, whereas the genomic dna bac library was done with hindiii partial digestion. with the chromosome walking strategy ... | 2008 | 18338570 |
bacillus spore classification via surface-enhanced raman spectroscopy and principal component analysis. | surface-enhanced raman spectroscopy (sers) can provide rapid fingerprinting of biomaterial in a nondestructive manner. the adsorption of colloidal silver to biological material suppresses native biofluorescence while providing electromagnetic surface enhancement of the normal raman signal. this work validates the applicability of qualitative ser spectroscopy for analysis of bacterial species by utilizing principal component analysis (pca) to show discrimination of biological threat simulants, ba ... | 2008 | 18339232 |
a new group of parasporal inclusions encoded by the s-layer gene of bacillus thuringiensis. | bacillus thuringiensis produces various groups of active proteins, such as cyt, vip and parasporin, in addition to the cry protein. in this study we show s-layer proteins to be a new group of parasporal inclusions of b. thuringiensis. the s-layer consists of a two-dimensional lattice structure and is the outermost component of many archaeobacteria and eubacteria. the parasporal inclusion of b. thuringiensis strain ctc was found to be not a typical crystal protein encoded by the cry gene, but a p ... | 2008 | 18341579 |
role of helix b residues in interfacial activation of a bacterial phosphatidylinositol-specific phospholipase c. | the bacillus thuringiensis phosphatidylinositol-specific phospholipase c (pi-plc), an interfacial enzyme associated with prokaryotic infectivity, is activated by binding to zwitterionic surfaces, particularly phosphatidycholine (pc). two tryptophan residues (trp47 in the two-turn helix b and trp242 in a disordered loop) at the rim of the barrel structure are critical for this interaction. the helix b region (ile43 to gly48) in wild-type pi-plc orients the side chains of ile43 and trp47 so that t ... | 2008 | 18345643 |
reduced fitness of daphnia magna fed a bt-transgenic maize variety. | genetically modified (gm) maize expressing the bt-toxin cry1ab (bt-maize) was tested for effects on survival, growth, and reproduction of the water flea daphnia magna, a crustacean arthropod commonly used as a model organism in ecotoxicological studies. in three repeated experiments, d. magna were fed 100% ground maize in suspension, using either gm or isogenic unmodified (um) maize. d. magna fed gm-maize showed a significantly reduced fitness performance: the mortality was higher, a lower propo ... | 2008 | 18347840 |
selection of nontarget arthropod taxa for field research on transgenic insecticidal crops: using empirical data and statistical power. | one of the possible adverse effects of transgenic insecticidal crops is the unintended decline in the abundance of nontarget arthropods. field trials designed to evaluate potential nontarget effects can be more complex than expected because decisions to conduct field trials and the selection of taxa to include are not always guided by the results of laboratory tests. also, recent studies emphasize the potential for indirect effects (adverse impacts to nontarget arthropods without feeding directl ... | 2008 | 18348790 |
cry1f protein not detected in soil after three years of transgenic bt corn (1507 corn) use. | to evaluate the potential of bacillus thuringiensis (bt) cry1f protein accumulation in soil, transgenic corn containing event das-01507-1 encoding the cry1f gene was grown in three field sites for 3 consecutive yr, and the corn plants were incorporated into the soil through postseason tillage or no tillage each year. soil samples were collected from these fields, and the level of cry1f protein in these samples was determined using an enzyme-linked immunosorbent assay (elisa) with a synthetic inv ... | 2008 | 18348818 |
tri-trophic interactions between bt cotton, the herbivore aphis gossypii glover (homoptera: aphididae), and the predator chrysopa pallens (rambur) (neuroptera: chrysopidae). | tri-trophic impacts of transgenic bacillus thuringiensis (bt) cotton gk12 and nucotn 99b were studied using a predator, the great lacewing chrysopa pallens (rambur), and its prey, the cotton aphid aphis gossypii glover, in laboratory feeding experiments. the parental nontransgenic cotton cultivar of gk12 was used as control. the predator was fed with uniform (aphids from a single cultivar) or mixed prey (aphids from the three cotton cultivars provided on alternate days). mortality and developmen ... | 2008 | 18348819 |
specific activity of a bacillus thuringiensis strain against locusta migratoria manilensis. | bacillus thuringiensis (bt) has played an important role in biocontrol of pests. however, insecticidal activity of b. thuringiensis against locusts has been rarely reported. bt strain bth-13 exhibiting specific activity to locusts was isolated from a soil sample in china and characterized. its bipyramidal parasporal crystal is mainly composed of a protein of 129kda, and produces a mature toxin of 64kda after activation. the pattern of total dna from bth-13 showed a large and three small plasmid ... | 2008 | 18359040 |
detection of genes encoding antimicrobial peptides in mexican strains of trichoplusia ni (hübner) exposed to bacillus thuringiensis. | the systemic immune response of trichoplusia ni after bacillus thuringiensis (bt) exposure was evaluated by comparing the expression of genes encoding antimicrobial peptides (amps) in bt-susceptible and -resistant t. ni strains that were either exposed or not to xentari (bt-xt). amp genes were detected by rt-pcr using primers for attacin, gloverin, lebocin, lysozyme, and peptidoglycan recognition peptide (pgrp). in general, amp genes were detected more frequently in mexican field strains previou ... | 2008 | 18359041 |
solid-phase extraction of copper, iron and zinc ions on bacillus thuringiensis israelensis loaded on dowex optipore v-493. | bacillus thuringiensis israelensis loaded on dowex optipore v-493 as new adsorbent for the separation-preconcentration of heavy metal ions has been proposed. the analytical conditions for the quantitative recoveries of copper(ii), iron(iii) and zinc(ii) including ph, amounts of adsorbent, sample volume, etc. were investigated. the influences of alkaline and earth alkaline ions were also reported. the recovery values for the analytes are generally higher than 95%. the preconcentration factor was ... | 2008 | 18359563 |
[use of dir-pcr for elaboration of molecular markers of intraspecies bacterial groups as exemplified by bacillus thuringiensis]. | a recently developed pcr-fingerprinting method, the so-called dir (diverged inverted repeats)-pcr, was used for quick search for molecular markers of bacillus thuringiensis subspecies carrying the cry1 genes. the analysis of the fingerprints obtained by this method made it possible to reveal pcr fragments characteristic of the subspecies that produce proteins toxic for insects of the order lepidoptera. cloning and sequencing of these fragments allowed systems of scar (sequence characterized ampl ... | 2008 | 18365720 |
developing new approaches for detecting and preventing aedes aegypti population outbreaks: basis for surveillance, alert and control system. | a new approach to dengue vector surveillance based on permanent egg-collection using a modified ovitrap and bacillus thuringiensis israelensis(bti) was evaluated in different urban landscapes in recife, northeast brazil. from april 2004 to april 2005, 13 egg-collection cycles of four weeks were carried out. geo-referenced ovitraps containing grass infusion, bti and three paddles were placed at fixed sampling stations distributed over five selected sites. continuous egg-collections yielded more t ... | 2008 | 18368236 |
comparison of grain from corn rootworm resistant transgenic das-59122-7 maize with non-transgenic maize grain in a 90-day feeding study in sprague-dawley rats. | das-59122-7 (59122) is a transgenic maize (zea mays l.) that contains genes encoding cry34ab1 and cry35ab1 proteins from bacillus thuringiensis berliner strain 149b1 and phosphinothricin acetyltransferase (pat) protein from streptomyces viridochromogenes. expression of these proteins in planta confers resistance to corn rootworms and other coleopteran parasites and tolerance to herbicides containing glufosinate ammonium, respectively. in the current study, processed flours from 59122 maize grain ... | 2008 | 18381227 |
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, ... | 2008 | 18236038 |
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 ... | 2008 | 18236110 |
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 ... | 2008 | 18239893 |
deletion of dnan1 generates a mutator phenotype in bacillus anthracis. | the dnan gene in eubacteria is an essential gene that encodes the beta subunit of replicative dna polymerase. nearly all eubacterial genomes sequenced to date predict a single copy of the dnan gene in a well-conserved neighboring gene context. however, 19 genomes out of 348 scanned, including bacillus anthracis, bacillus cereus, bacillus thuringiensis, and bacillus weihenstephanensis, predict more than one dnan gene. in most cases, these genomes appear to maintain a copy of the dnan homolog in i ... | 2008 | 18242150 |
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 ... | 2008 | 18243589 |
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. | 2008 | 18248369 |
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 ... | 2008 | 18248430 |
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 ... | 2008 | 18257958 |
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 ... | 2008 | 18259177 |
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 ... | 2008 | 18259812 |
expression and characterization of aiia gene from bacillus subtilis bs-1. | ahl-lactonase (aiia), a metallo-beta-lactamase produced by bacillus thuringiensis, bacillus cereus and bacillus anthracis, specifically hydrolyzes n-acyl-homoserine lactones (ahls) secreted by gram-negative bacteria and thereby attenuates the symptoms caused by plant pathogens. in this study, an aiia gene was cloned from bacillus subtilis bs-1 by pcr with a pair of degenerate primers. the deduced 250 amino acid sequence contained two small conserved regions, 103shlhfdh109 and 166tpghtpgh173, whi ... | 2008 | 18261893 |
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. | 2008 | 18266703 |
in vitro assembly studies of ftsz/tubulin-like proteins (tubz) from bacillus plasmids: evidence for a capping mechanism. | proteins with a weak sequence similarity to tubulin and ftsz are expressed from large plasmids of bacillus anthracis and bacillus thuringiensis and are probably involved in plasmid segregation. previously designated repx and tubz, we designate them here as tubz-ba and tubz-bt. we have expressed and purified the proteins for in vitro studies. tubz-ba and tubz-bt share only 21% amino acid identity, but they have remarkably similar biochemical properties. they both assemble into two-stranded filame ... | 2008 | 18198178 |
plant cyclotides disrupt epithelial cells in the midgut of lepidopteran larvae. | several members of the rubiaceae and violaceae plant families produce a series of cyclotides or macrocyclic peptides of 28-37 aa with an embedded cystine knot. the cyclic peptide backbone together with the knotted and strongly braced structure confers exceptional chemical and biological stability that has attracted attention for potential pharmaceutical applications. cyclotides display a diverse range of biological activities, such as uterotonic action, anti-hiv activity, and neurotensin antagon ... | 2008 | 18202177 |
does cry1ab protein affect learning performances of the honey bee apis mellifera l. (hymenoptera, apidae)? | genetically modified bt crops are increasingly used worldwide but side effects and especially sublethal effects on beneficial insects remain poorly studied. honey bees are beneficial insects for natural and cultivated ecosystems through pollination. the goal of the present study was to assess potential effects of two concentrations of cry1ab protein (3 and 5000 ppb) on young adult honey bees. following a complementary bioassay, our experiments evaluated effects of the cry1ab on three major life ... | 2008 | 18206234 |
genetic mapping of bt-toxin binding proteins in a cry1a-toxin resistant strain of diamondback moth plutella xylostella. | a major mechanism of resistance to bacillus thuringiensis (bt) toxins in lepidoptera is a reduction of toxin binding to sites in the midgut membrane. genetic studies of three different species have shown that mutations in a candidate bt receptor, a 12-cadherin-domain protein, confer cry1a toxin resistance. despite a similar resistance profile in a fourth lepidopteran species, plutella xylostella, we have previously shown that the cadherin orthologue maps to a different linkage group (lg8) than c ... | 2008 | 18207074 |
the influence of different nutrient levels on insect-induced plant volatiles in bt and conventional oilseed rape plants. | transgenic bt (expressing the cry1ac endotoxin gene) and conventional oilseed rape plants grown in different soils were used to study nutrient uptake and emission of volatiles after herbivore damage. all plants were greenhouse-grown in soils representing low-, medium- and high-nutrient levels. the concentrations of n, p, k, mg and zn were significantly affected by the transgene, while the main effect of soil type appeared in n, p, ca, mg, b, mn and zn concentrations in the plants. plants with fo ... | 2008 | 18211550 |
immunotoxicological studies of genetically modified rice expressing pha-e lectin or bt toxin in wistar rats. | as part of the safotest project the immunmodulating effect of cry1ab protein from bacillus thuringiensis (bt) and pha-e lectin from kidney bean (phaseolus vulgaris erythroagglutinin) was examined in 28- and 90-day feeding studies in wistar rats. pha-e lectin was chosen as positive control. rats were fed control rice, transgenic rice expressing cry1ab protein or pha-e lectin, or transgenic rice spiked with the purified recombinant protein. total immunoglobulin levels, mitogen-induced cell prolife ... | 2008 | 18215453 |
molecular characterization of virulence defects in bacillus thuringiensis mutants. | sequence analysis of a virulence-attenuated bacillus thuringiensis signature tagged mutant 6f8 led to the identification of an 18 182 bp locus encoding 29 potential protein-coding orfs. thirteen of the 29 putative orfs were found to share extensive homology with genes on plasmid pe33l466 of the pathogenic bacillus cereus e33l strain. nine orfs were not only found in a cluster, but also in the same gene order, in both organisms. a number of mobile elements, including a transposon tn4430, a novel ... | 2008 | 18218018 |
blocking binding of bacillus thuringiensis cry1aa to bombyx mori cadherin receptor results in only a minor reduction of toxicity. | bacillus thuringiensis cry1aa insecticidal protein is the most active known b. thuringiensis toxin against the forest insect pest lymantria dispar (gypsy moth), unfortunately it is also highly toxic against the non-target insect bombyx mori (silk worm). | 2008 | 18218126 |
a tool box for operational mosquito larval control: preliminary results and early lessons from the urban malaria control programme in dar es salaam, tanzania. | as the population of africa rapidly urbanizes, large populations could be protected from malaria by controlling aquatic stages of mosquitoes if cost-effective and scalable implementation systems can be designed. | 2008 | 18218148 |
study of bt impact on caddisflies overstates its conclusions: response to rosi-marshall et al. | 2008 | 18218776 | |
molecular characterization of spodoptera frugiperda-bacillus thuringiensis cry1ca toxin interaction. | the use of bacillus thuringiensis cry delta-endotoxins as bioinsecticides is threatened by the possibility of pest resistance. determining transcriptional profiles of midgut cells early in cry toxin poisoning is crucial for understanding the biochemical and molecular aspects of insect detoxification and for sustained use of such toxins. in this study, transcriptional responses of midgut cells from spodoptera frugiperda third-instar larvae following treatment with cry1ca were investigated. suppre ... | 2008 | 18222513 |
bacillus thuringiensis cry1ac toxin-binding and pore-forming activity in brush border membrane vesicles prepared from anterior and posterior midgut regions of lepidopteran larvae. | it is generally accepted that bacillus thuringiensis cry toxins insert into the apical membrane of the larval midgut after binding to specific receptors, and there is evidence that the distribution of binding molecules along the midgut is not uniform. by use of the voltage-sensitive dye disc(3)(5) and (125)i-labeled cry1ac, we have measured the effect of cry1ac in terms of permeabilization capacity and of binding parameters on brush border membrane vesicles (bbmv) prepared from the anterior and ... | 2008 | 18223107 |
employing phage display to study the mode of action of bacillus thuringiensis cry toxins. | phage display is an in vitro method for selecting polypeptides with desired properties from a large collection of variants. the insecticidal cry toxins produced by bacillus thuringiensis are highly specific to different insects. various proteins such as cadherin, aminopeptidase-n (apn) and alkaline phosphatase (alp) have been characterized as potential cry-receptors. we used phage display to characterize the cry toxin-receptor interaction(s). by employing phage-libraries that display single-chai ... | 2008 | 18226423 |
the pre-pore from bacillus thuringiensis cry1ab toxin is necessary to induce insect death in manduca sexta. | the insecticidal cry toxins from bacillus thuringiensis bacteria are pore-forming toxins that lyse midgut epithelial cells in insects. we have previously proposed that they form pre-pore oligomeric intermediates before membrane insertion. for formation of these oligomers coiled-coil structures are important, and helix alpha-3 from cry toxins could form coiled-coils. our data shows that different mutations in helix alpha-3 are affected in pore formation and toxicity. mutants affected in toxicity ... | 2008 | 18226424 |
enhanced exocytosis of the receptor bt-r(1) induced by the cry1ab toxin of bacillus thuringiensis directly correlates to the execution of cell death. | cry1ab toxin produced by bacillus thuringiensis exerts insecticidal action upon binding to bt-r(1), a cadherin receptor localized in the midgut epithelium of the tobacco hornworm manduca sexta. the univalent binding of toxin to receptor transmits a death signal into the cell and turns on a multi-step signal transduction pathway involving adenylyl cyclase (ac) and protein kinase a (pka), which drives the biochemical events that culminate in oncotic cell death. here, we report that cell killing by ... | 2008 | 18230416 |
structure of the claudin-binding domain of clostridium perfringens enterotoxin. | clostridium perfringens enterotoxin is a common cause of food-borne and antibiotic-associated diarrhea. the toxin's receptors on intestinal epithelial cells include claudin-3 and -4, members of a large family of tight junction proteins. toxin-induced cytolytic pore formation requires residues in the nh(2)-terminal half, whereas residues near the cooh terminus are required for binding to claudins. the claudin-binding cooh-terminal domain is not toxic and is currently under investigation as a pote ... | 2008 | 17977833 |
uses of plant lectins in bioscience and biomedicine. | new research directions in the last decade have led to major developments in the uses of plant lectins in bioscience and biomedicine. major advances have been made in our understanding how lectins in the diet can act on the gastrointestinal tract and the physiological consequences of their actions, and how they can modulate body- and organ metabolism, the immune system and the gut microflora. particularly striking progress has been made in unravelling the effects, often beneficial, of both orall ... | 2008 | 17981618 |
comparison and validation of methods to quantify cry1ab toxin from bacillus thuringiensis for standardization of insect bioassays. | standardization of toxin preparations derived from bacillus thuringiensis (berliner) used in laboratory bioassays is critical for accurately assessing possible changes in the susceptibility of field populations of target pests. different methods were evaluated to quantify cry1ab, the toxin expressed by 80% of the commercially available transgenic maize that targets the european corn borer, ostrinia nubilalis (hübner). we compared three methods of quantification on three different toxin preparati ... | 2008 | 17981939 |
cell wall carbohydrate compositions of strains from the bacillus cereus group of species correlate with phylogenetic relatedness. | members of the bacillus cereus group contain cell wall carbohydrates that vary in their glycosyl compositions. recent multilocus sequence typing (mlst) refined the relatedness of b. cereus group members by separating them into clades and lineages. based on mlst, we selected several b. anthracis, b. cereus, and b. thuringiensis strains and compared their cell wall carbohydrates. the cell walls of different b. anthracis strains (clade 1/anthracis) were composed of glucose (glc), galactose (gal), n ... | 2008 | 17981984 |
supercat: a supertree database for combined and integrative multilocus sequence typing analysis of the bacillus cereus group of bacteria (including b. cereus, b. anthracis and b. thuringiensis). | the bacillus cereus group of bacteria is an important group including mammalian and insect pathogens, such as b. anthracis, the anthrax bacterium, b. thuringiensis, used as a biological pesticide and b. cereus, often involved in food poisoning incidents. to characterize the population structure and epidemiology of these bacteria, five separate multilocus sequence typing (mlst) schemes have been developed, which makes results difficult to compare. therefore, we have developed a database that comp ... | 2008 | 17982177 |
changes of inheritance mode and fitness in helicoverpa armigera (hübner) (lepidoptera: noctuidae) along with its resistance evolution to cry1ac toxin. | the changes of inheritance mode and fitness of resistance in helicoverpa armigera (hübner) along with its resistance evolution to cry1ac toxin were evaluated in the laboratory. the resistance levels reached 170.0-, 209.6- and 2893.3-fold, on selection of the field population in the 16th (btr-f(16)), 34th (btr-f(34)) and 87th (btr-f(87)) generation with artificial diet containing cry1ac toxin, respectively. as the resistance levels increased, more larvae feeding on the bt cotton expressing cry1ac ... | 2008 | 17950749 |
isolation and characterization of bacillus thuringiensis strains from olive-related habitats in turkey. | to isolate bacillus thuringiensis strains from different olive-related habitats (olive groves and olive oil factories) in turkey and to characterize these strains by molecular methods. | 2008 | 17927757 |
expression of chitinase a (chia) gene from a local isolate of serratia marcescens in coleoptera-specific bacillus thuringiensis. | the present study focused on cloning and expression of chia gene from a highly chitinolytic local isolate of serratia marcescens in an anti-coleopteran bacillus thuringiensis and comparison of the characteristics of the native and recombinant chias. | 2008 | 17927758 |
the inactivation and removal of airborne bacillus atrophaeus endospores from air circulation systems using uvc and hepa filters. | to (i) evaluate the uv radiation in the 'c' band/high efficient particulate air (uvc/hepa) instrument's potential to inactivate spores of bacillus atrophaeus and selected bacillus species and (ii) test whether a titanium dioxide coating inside the cylindrical hepa filter improves the system's efficacy. | 2008 | 17927759 |
distribution and diversity of dipteran-specific cry and cyt genes in native bacillus thuringiensis strains obtained from different ecosystems of iran. | one hundred and twenty-eight bacillus thuringiensis isolates from fields of different ecological regions of iran were collected to study the distribution and diversity of dipteran-specific cry and cyt genes. the percentage of samples with bt showed significant differences between different regions and also between different fields. the most bt frequency was observed in the soil samples collected from caspianic zone (7%) and soils of cotton (17%). characterization of isolates was based on morphol ... | 2008 | 17999100 |
raft-targeting and oligomerization of parasporin-2, a bacillus thuringiensis crystal protein with anti-tumour activity. | parasporin-2 is a newly classified bacillus thuringiensis crystal toxin with strong cytocidal activities toward human liver and colon cancer cells. similar to other insecticidal b. thuringiensis crystal toxins, parasporin-2 shows target specificity and damages the cellular membrane. however, the mode of parasporin-2 actions toward the cell membrane remains unknown. here, we show that this anti-tumour crystal toxin targets lipid rafts and assembles into oligomeric complexes in the membrane of hum ... | 2008 | 18006515 |
optimization of spray-drying conditions for the large-scale preparation of bacillus thuringiensis var. israelensis after downstream processing. | reduction of water activity in the formulations of mosquito biocontrol agent, bacillus thuringiensis var. israelensis is very important for long term and successful storage. a protocol for spray drying of b. thuringiensis var. israelensis was developed through optimizing parameters such as inlet temperature and atomization type. a indigenous isolate of b. thuringiensis var. israelensis (vcrc b-17) was dried by freeze and spray drying methods and the moisture content and mosquito larvicidal activ ... | 2008 | 18023058 |
an engineered chymotrypsin/cathepsin g site in domain i renders bacillus thuringiensis cry3a active against western corn rootworm larvae. | the western corn rootworm remains one of the most important pests of corn in the united states despite the use of many pest management tools. cry3a, the first coleopteran-active bacillus thuringiensis toxin isolated, has not been useful for control of the corn rootworm pest complex. modification of cry3a so that it contained a chymotrypsin/cathepsin g protease recognition site in the loop between alpha-helix 3 and alpha-helix 4 of domain i, however, resulted in consistent activity of the toxin ( ... | 2008 | 18024675 |
production and characterization of bacillus thuringiensis cry1ac-resistant cotton bollworm helicoverpa zea (boddie). | laboratory-selected bacillus thuringiensis-resistant colonies are important tools for elucidating b. thuringiensis resistance mechanisms. however, cotton bollworm, helicoverpa zea, a target pest of transgenic corn and cotton expressing b. thuringiensis cry1ac (bt corn and cotton), has proven difficult to select for stable resistance. two populations of h. zea (ar and mr), resistant to the b. thuringiensis protein found in all commercial bt cotton varieties (cry1ac), were established by selection ... | 2008 | 18024681 |
plasmid patterns of bacillus thuringiensis type strains. | practically all bacillus thuringiensis strains contain a set of self-replicating, extrachromosomal dna molecules or plasmids, which vary in number and size in the different strains. the plasmid patterns obtained from gel electrophoresis have previously been used as a tool to characterize strains, but comparison of the plasmid patterns has been limited in the number and diversity of strains analyzed. in this report, we were able to compare the plasmid patterns of 83 type strains (out of 84) and 4 ... | 2008 | 18024687 |
evidence of the importance of the met115 for bacillus thuringiensis subsp. israelensis cyt1aa protein cytolytic activity in escherichia coli. | cyt1aa is a cytolytic toxin, found together with the delta-endotoxins in bacillus thuringiensis subsp. israelensis parasporal insecticidal crystals. the latter are used as an environmental friendly insecticide against mosquitoes and black flies. contrary to cry delta-endotoxin, the mode of action of cyt1aa is not completely understood. in the absence of direct structural data, a novel mutated cyt1aa gene was used to obtain indirect informations on cyt1aa conformation changes in the lipid membran ... | 2008 | 17989942 |
sequential transformation to pyramid two bt genes in vegetable indian mustard (brassica juncea l.) and its potential for control of diamondback moth larvae. | vegetable indian mustard (brassica juncea cv. "green wave") plants that control plutella xylostella (diamondback moth) (dbm) were produced by introduction of one or two bacillus thuringiensis (bt) genes. a cry1ac bt gene associated with the nptii gene for kanamycin selection or a cry1c bt gene with the hpt gene for hygromycin selection was introduced individually through agrobacterium-mediated transformation of seedling explants. a cry1c line was then transformed with the cry1ac gene to produce ... | 2008 | 17989981 |
coconut water as a cheap source for the production of delta endotoxin of bacillus thuringiensis var. israelensis, a mosquito control agent. | bacillus thuringiensis var. israelensis (b. t. i.) is being widely used in mosquito control programs. however, the large-scale production of this bacillus is expensive due to the high cost of the production medium. in this study, we attempted to develop a cost-effective medium, based on a locally available raw material namely coconut water which is available in plenty as waste product from coconut oil industry. the yield of cell mass, sporulation and mosquito larvicidal activity were studied by ... | 2008 | 17963708 |
the insecticidal crystal protein cry2ab10 from bacillus thuringiensis: cloning, expression, and structure simulation. | the cry2ab-type gene was cloned from bacillus thuringiensis and designated as cry2ab10. the recombinant cry2ab10 protein expressed in e. coli cells shows high toxicity against plutella xylostella. the protein structure was constructed by homology modeling, and the receptor-binding sites were predicted by a molecular docking method. | 2008 | 17973088 |
the ecology of bacillus thuringiensis on the phylloplane: colonization from soil, plasmid transfer, and interaction with larvae of pieris brassicae. | seedlings of clover (triflorium hybridum) were colonized by bacillus thuringiensis when spores and seeds were co-inoculated into soil. both a strain isolated in the vegetative form from the phylloplane of clover, 2810-s-4, and a laboratory strain, hd-1, were able to colonize clover to a density of about 1000 cfu/g leaf when seeds were sown in sterile soil and to a density of about 300 cfu/g leaf in nonsterile soil. a strain lacking the characteristic insecticidal crystal proteins produced a simi ... | 2008 | 17973155 |
effects of defoliating insect resistance qtls and a cry1ac transgene in soybean near-isogenic lines. | the crystal proteins coded by transgenes from bacillus thuringiensis (bt) have shown considerable value in providing effective insect resistance in a number of crop species, including soybean, glycine max (l.) merr. additional sources of soybean insect resistance would be desirable to manage the development of tolerance/resistance to crystal proteins by defoliating insects and to sustain the deployment of bt crops. the objective of this study was to evaluate the effects and interactions of three ... | 2008 | 18064435 |
effects of transgenic corn and cry1ab protein on the nematode, caenorhabditis elegans. | the effects of the insecticidal cry1ab protein from bacillus thuringiensis (bt) on the nematode, caenorhabditis elegans, were studied with soil from experimental fields cultivated with transgenic bt corn (mon810) and with trypsinized cry1ab protein expressed in escherichia coli. the content of cry1ab protein was above the detection limit of an elisa test in only half of the soil samples obtained from transgenic plots, ranging from 0.19 to 1.31 ng g(-1) dry weight. in a laboratory bioassay, c. el ... | 2008 | 18068780 |
broad distribution of enterotoxin genes (hblcda, nheabc, cytk, and entfm) among bacillus thuringiensis and bacillus cereus as shown by novel primers. | eight new pairs of pcr primers were designed and efficiently detect eight toxin genes (hblc, hbld, hbla, nhea, nheb, nhec, cytk, and entfm) in 411 b. cereus strains (121 food- and 290 soil isolates) and 205 b. thuringiensis strains (43 serovars, 10 food- and 152 soil isolates). according to the presence of these eight toxin genes, they were divided into four groups among the total 616 isolates. in group i, all eight genes occurred simultaneously in 403 (65.42%) isolates, while group ii (134 isol ... | 2008 | 18068844 |
endospore dipicolinic acid detection during bacillus thuringiensis culture. | the aim of this work was to detect bacillus thuringiensis endospore production during fermentation under conditions hindering endospore detection, i.e. in a complex undefined industrial medium with a high content of solids in suspension. | 2008 | 18069985 |
isolation and characterization of nonrhizobial plant growth promoting bacteria from nodules of kudzu (pueraria thunbergiana) and their effect on wheat seedling growth. | the leguminous vine kudzu (pueraria thunbergiana) is an introduction into the n. w. himalayan region of india. despite its value as a fodder and cover crop, little is known about the nature of the nodule microflora. in an attempt to study the nodule bacteria, we isolated and characterized three nonrhizobial plant growth promoting bacteria from surface sterilized nodules of kudzu. based on the sequencing of the 16 s r rna gene, the isolates were designated as bacillus thuringiensis kr-1, enteroba ... | 2008 | 18074178 |
the occurrence of bacillus cereus, b. thuringiensis and b. mycoides in chinese pasteurized full fat milk. | in 2006, a total of 54 samples of pasteurized full fat milk packaged in cartons were collected in spring and in autumn from chain supermarkets in wuhan, china. the samples were examined and enumerated by mpn methods strictly according to guidelines laid out in us fda/cfsan bam chapter 14. among 102 isolated b. cereus-like bacteria, 92 isolates were identified to be b. cereus, 9 b. thuringiensis and 1 b. mycoides. it was found that the occurrences of b. cereus were 71.4% and 33.3% in spring and i ... | 2008 | 18077041 |
molecular and biochemical characterization of an endochitinase (chia-hd73) from bacillus thuringiensis subsp. kurstaki hd-73. | an endochitinase gene (chia-hd73) from the insecticidal bacterium bacillus thuringiensis subsp. kurstaki hd-73 was cloned, sequenced, and expressed in escherichia coli dh5alphaf'. the chitinase activity of the encoded protein was studied in assays with different fluorogenic substrates. the chia-hd73 gene contained an open-reading frame that encoded an endochitinase with a deduced molecular weight and an isoelectric point of, respectively, 74.5 kda and 5.75. a putative signal peptide with cleavag ... | 2008 | 18080218 |
susceptibility of spodoptera exigua to 9 toxins from bacillus thuringiensis. | nine of the most common lepidopteran active cry proteins from bacillus thuringiensis have been tested for activity against spodoptera exigua. because of possible intraspecific variability, three laboratory strains (fra, hol, and mur) have been used. mortality assays were performed with the three strains. lc(50) values for the active toxins were determined to the fra and the hol strains, whereas susceptibility of the mur strain was assessed using only two concentrations. the results showed that c ... | 2008 | 18082763 |
hydrogen and polyhydroxybutyrate producing abilities of microbes from diverse habitats by dark fermentative process. | thirty five bacterial isolates from diverse environmental sources such as contaminated food, nitrogen rich soil, activated sludges from pesticide and oil refineries effluent treatment plants were found to belong to bacillus, bordetella, enterobacter, proteus, and pseudomonas sp. on the basis of 16s rrna gene sequence analysis. under dark fermentative conditions, maximum hydrogen (h(2)) yields (mol/mol of glucose added) were recorded to be 0.68 with enterobacter aerogenes egu16 followed by 0.63 w ... | 2008 | 18083024 |
novel isolate of bacillus thuringiensis subsp. thuringiensis that produces a quasicuboidal crystal of cry1ab21 toxic to larvae of trichoplusia ni. | a new isolate (is5056) of bacillus thuringiensis subsp. thuringiensis that produces a novel variant of cry1ab, cry1ab21, was isolated from soil collected in northeastern poland. cry1ab21 was composed of 1,155 amino acids and had a molecular mass of 130.5 kda, and a single copy of the gene coding for this endotoxin was located on a approximately 75-kbp plasmid. when synthesized by the wild-type strain, cry1ab21 produced a unique, irregular, bipyramidal crystal whose long and short axes were both ... | 2008 | 18083867 |
intranasal immunization with naegleria fowleri lysates and cry1ac induces metaplasia in the olfactory epithelium and increases iga secretion. | according to previous reports, intranasal administration of the cry1ac protein alone or with amoebic lysates increases protection against naegleria fowleri meningoencephalitis in mice, apparently by eliciting iga responses in the nasal mucosa. in the current study, we performed an immunohistochemical analysis of iga in the nasal mucosa of mice immunized intranasally with cry1ac, and amoebic lysates or a combination of both. the animals were sacrificed 24 h after the last immunization or after an ... | 2008 | 18086014 |
toxicological safety assessment of genetically modified bacillus thuringiensis with additional n-acyl homoserine lactonase gene. | the aim of the present study is to evaluate the toxicology safety to mammals of a genetically modified (gm) bacillus thuringiensis with an additional n-acyl homoserine lactones gene (aiia), which possesses insecticidal activity together with restraint of bacterial pathogenicity and is intended for use as a multifunctional biopesticide. safety assessments included an acute oral toxicity test and 28-d animal feeding study in wistar rats, primary eye and dermal irritation in zealand white rabbits, ... | 2008 | 18092859 |
retention of mosquito larvicidal activity of lyophilized cells and wdp formulation of bacillus thuringiensis var. israelensis on long-term storage. | lyophilized cells (sealed and unsealed) and water dispersible powders (wdps) of two indigenous isolates of bacillus thuringiensis var.israelensis were stored at -10, 4, 30 and 40 degrees c for up to 4 years and checked for activity. lyophilized cells stored in sealed condition at -10, 4 and 30 degrees c and wdps stored at -10 and 4 degrees c were found to maintain the activity fairly well. the lyophilized cells stored at 30 degrees c and wdps stored at 4 degrees c maintained their larvicidal pro ... | 2008 | 18155180 |
development and validation of a sensitive enzyme immunoassay for surveillance of cry1ab toxin in bovine blood plasma of cows fed bt-maize (mon810). | the increasing global adoption of genetically modified (gm) plant derivatives in animal feed has provoked a strong demand for an appropriate detection method to evaluate the existence of transgenic protein in animal tissues and animal by-products derived from gm plant fed animals. a highly specific and sensitive sandwich enzyme immunoassay for the surveillance of transgenic cry1ab protein from bt-maize in the blood plasma of cows fed on bt-maize was developed and validated according to the crite ... | 2008 | 18155416 |
genetic evidence for the actin homolog gene mrebh and the bacitracin resistance gene bcrc as targets of the alternative sigma factor sigi of bacillus subtilis. | the bacillus subtilis sigi gene, which is a member of the class vi heat shock genes of the b. subtilis heat shock stimulon, encodes an alternative sigma factor whose regulon is poorly defined. in this study, by using a binary vector system, we showed that b. subtilis sigi could drive expression of a transcriptional fusion between the sigi regulatory region from bacillus licheniformis, bacillus sp. strain nrrl b-14911, b. subtilis, or bacillus thuringiensis and the xyle reporter gene in b. subtil ... | 2008 | 18156261 |