Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| method for the detection of synthetic cry3a in transgenic potatoes. | all transgenic cultivars of potatoes registered in canada and the united states have been modified to express a synthetic cry3a gene as a means of conferring resistance against the colorado potato beetle, an important economic pest of potatoes. a pcr method was developed to amplify a 499 bp region of the synthetic cry3a gene. using this method, synthetic cry3a could be detected in six different transgenic cultivars. positive results could be confirmed with pvuii restriction digestion of the pcr- ... | 2004 | 14969535 |
| long-term selection for resistance to transgenic cotton expressing bacillus thuringiensis toxin in helicoverpa armigera (hübner) (lepidoptera: noctuidae). | selection experiments for resistance to transgenic bt cotton expressing cry1ac toxin in helicoverpa armigera (hübner) were conducted using a leaf-feeding method with 42 selection episodes over 45 generations. the cotton bollworm developed resistance to transgenic bt cotton after 12 generations (f12) of selection. the survival rate of f12 neonates feeding on leaves of seedling stage for 4 days and boll-opening stage for 5 days of r19 line were ca 34 and 72%, respectively, compared with ca 0 and 4 ... | 2004 | 14971684 |
| analysis of glycan structures on the 120 kda aminopeptidase n of manduca sexta and their interactions with bacillus thuringiensis cry1ac toxin. | the bacillus thuringiensis cry1ac toxin specifically binds to a 120 kda aminopeptidase n (apn) receptor in manduca sexta. the binding interaction is mediated by galnac, presumably covalently attached to the apn as part of an undefined glycan structure. here we detail a simple, rapid and specific chemical deglycosylation technique, applicable to glycoproteins immobilized on western blots. we used the technique to directly and unambiguously demonstrate that carbohydrates attached to 120 kda apn ar ... | 2004 | 14976987 |
| induction and transmission of bacillus thuringiensis tolerance in the flour moth ephestia kuehniella. | the use of bacillus thuringiensis (bt) endotoxins to control insect vectors of human diseases and agricultural pests is threatened by the possible evolution of resistance in major pest species. in addition to high levels of resistance produced by receptor insensitivity (5, 16, 17), several cases of tolerance to low to medium levels of toxin have been reported in laboratory colonies of lepidopteran species (3, 18). because the molecular basis of some of these cases of tolerance to the toxin are n ... | 2004 | 14978282 |
| a novel synthetic peptide derivative from lactoferrin exhibiting antimicrobial activity. | a tetrapeptide derivative boc-l-lys(boc)-l-arg-l-asp-l-ser(bu(t))-obu(t) (pep 1261; boc is butoxycarbonyl, bu(t) is t-butyl and obu(t) is t-butyl ester), synthesized by a solution-phase strategy, exhibited antimicrobial activity against a broad spectrum of micro-organisms at an optimal concentration of 500 mug/ml. whereas the tetrapeptide salt (l-lys-l-arg-l-asp-l-ser.hcl) was found to be fairly effective against bacterial cultures, it was not effective against fungal cultures. comparative growt ... | 2004 | 14992693 |
| novel cry gene from paenibacillus lentimorbus strain semadara inhibits ingestion and promotes insecticidal activity in anomala cuprea larvae. | a positive clone was selected from a library of total cell dna of paenibacillus lentimorbus strain semadara that reacted with an antiserum that was raised against parasporal crystal proteins produced by this strain. the positive clone had a dna insert containing two whole cry genes (cry43aa1, cry43ba1), one partial cry gene (cry43-like), and three smaller genes located upstream. eight blocks that are conserved in the cry proteins of bacillus thuringiensis [microbiol. mol. biol. rev. 62 (1998) 77 ... | 2004 | 14992857 |
| detection and quantitation of genetically modified maize (bt-176 transgenic maize) by applying ligation detection reaction and universal array technology. | we have applied the ligation detection reaction (ldr) combined with a universal array approach to the detection and quantitation of the polymerase chain reaction (pcr) amplified cry1a(b) gene from bt-176 transgenic maize. we demonstrated excellent specificity and high sensitivity. down to 0.5 fmol (nearly 60 pg) of pcr amplified transgenic material was unequivocally detected with excellent linearity within the 0.1-2.0% range with respect to wild-type maize. we suggest the feasibility of extendin ... | 2004 | 14995096 |
| lower fumonisin mycotoxin levels in the grain of bt corn grown in the united states in 2000-2002. | fumonisins were monitored in corn grain collected from bt hybrids grown in 107 locations across the united states in 2000-2002. bt corn hybrids contain the cry1ab protein from bacillus thuringiensis that controls european corn borers and other stalk-boring pests. fumonisin levels were frequently lower in grain from bt hybrids grown in field trials under conditions of natural (fact trials) or manual insect infestation (university trials). over three years of fact trials, there were 126/210 compar ... | 2004 | 14995151 |
| cross-linking phosphatidylinositol-specific phospholipase c traps two activating phosphatidylcholine molecules on the enzyme. | bacillus thuringiensis phosphatidylinositol-specific phospholipase c (pi-plc), a bacterial model for the catalytic domain of mammalian pi-plc enzymes, was cross-linked by 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride to probe for the aggregation and/or conformational changes of pi-plc when bound to activating phosphatidylcholine (pc) interfaces. dimers and higher order multimers (up to 31% of the total protein when cross-linked at ph 7) were observed when the enzyme was cross-linke ... | 2004 | 14996830 |
| interaction of two bacillus thuringiensis delta-endotoxins with the digestive system of lygus hesperus. | the active-toxin form of crylac (65 kda) or cry2ab was fed to a non-susceptible insect, lygus hesperus, in an artificial diet. biochemical and immunocytochemical methods were used to determine the distribution of ingested toxin. the toxins did not elicit a feeding deterrent response. crylac and cry2ab were ingested; small amounts were absorbed into the hemolymph as holoproteins, but most was excreted. sds-page analysis of crylac and cry2ab incubations with salivary gland homogenate showed a smal ... | 2004 | 15018095 |
| isolation and characterization of a strain of bacillus thuringiensis subsp. morrisoni pg-14 encoding delta-endotoxin cry1ac. | bacillus thuringiensis 656-3, isolated from a soil sample collected at mushroom houses, showed high toxicity to mushroom flies, lycoriella mali and coboldia fuscipes. b. thuringiensis 656-3 produced bipyramidal inclusions and reacted with the h antiserum of b. thuringiensis subsp. morrisoni (h8a8b). the plasmid and protein profiles of b. thuringiensis 656-3 were similar to those of its reference strain, subsp. morrisoni pg-14. however, pcr analysis using cry gene primers showed that b. thuringie ... | 2004 | 15018102 |
| bacillus thuringiensis toxin (cry1ab) has no direct effect on larvae of the green lacewing chrysoperla carnea (stephens) (neuroptera: chrysopidae). | earlier studies have shown that larvae of the green lacewing predator chrysoperla carnea are negatively affected when preying on lepidopteran larvae that had been fed with transgenic maize expressing the cry1ab gene from bacillus thuringiensis. to test whether the observed effects were directly caused by the cry1ab toxin, we have developed a bioassay which allows us to feed high concentrations of the toxin directly to the predator. the results of these feeding studies show no direct toxic effect ... | 2004 | 15019519 |
| a bacillus thuringiensis crystal protein with selective cytocidal action to human cells. | bacillus thuringiensis crystal proteins, well known to be toxic to certain insects but not pathogenic to mammals, are used as insecticidal proteins in agriculture and forest management. we here identified a crystal protein that is non-insecticidal and non-hemolytic but has strong cytocidal activity against various human cells with a markedly divergent target specificity, e.g. highly cytotoxic to hepg2 and jurkat and less cytotoxic to the normal hepatocyte (hc) and hela. in slices of liver and co ... | 2004 | 15026424 |
| bacillus thuringiensis delta-endotoxin binding to brush border membrane vesicles of rice stem borers. | the receptor binding step in the molecular mode of action of five delta-endotoxins (cry1ab, cry1ac, cry1c, cry2a, and cry9c) from bacillus thuringiensis was examined to find toxins with different receptor sites in the midgut of the striped stem borer (ssb) chilo suppressalis (walker) and yellow stem borer (ysb) scirpophaga incertulas (walker) (lepidoptera: pyralidae). homologous competition assays were used to estimate binding affinities (k(com)) of (125)i-labelled toxins to brush border membran ... | 2004 | 15027071 |
| identification of bacillus anthracis specific chromosomal sequences by suppressive subtractive hybridization. | bacillus anthracis, bacillus thuringiensis and bacillus cereus are closely related members of the b. cereus-group of bacilli. suppressive subtractive hybridization (ssh) was used to identify specific chromosomal sequences unique to b. anthracis. | 2004 | 15028116 |
| bacillus thuringiensis var. israelensis production involving re-use of the supernatant. | the supernatant arising after biomass separation of bacillus thuringiensis var. israelensis by flocculation/sedimentation was re-used after being supplemented with 25, 50 and 75% (w/v) of the original culture medium, based on corn steep liquor, glucose and mineral salts. supplementation at 75% gave a spore concentration (1 x 10(10) c.f.u. ml(-1)) five times greater than that obtained with the other supplements. | 2004 | 15000482 |
| reconstruction of bacillus thuringiensis ssp. israelensis cry11a endotoxin from fragments corresponding to its n- and c-moieties restores its original biological activity. | subtilisin hydrolyzes cry11a endotoxin (of 70 kd) produced by bacillus thuringiensis ssp. israelensis to fragments of 33- and 36-kd, which correspond to n- and c-terminal halves of the endotoxin molecule. thermitase (a serine protease from thermoactinomyces vulgaris) and insect gut proteases from diptera and lepidoptera exhibit the same hydrolytic effect on cry11a. hydrolyzates maintain high toxicity with respect to larvae of aedes aegypti, anopheles stephensi, and culex pipiens. the 33- and 36- ... | 2004 | 15000685 |
| interaction of bacillus thuringiensis toxins with larval midgut binding sites of helicoverpa armigera (lepidoptera: noctuidae). | in 1996, bt-cotton (cotton expressing a bacillus thuringiensis toxin gene) expressing the cry1ac protein was commercially introduced to control cotton pests. a threat to this first generation of transgenic cotton is the evolution of resistance by the insects. second-generation bt-cotton has been developed with either new b. thuringiensis genes or with a combination of cry genes. however, one requirement for the "stacked" gene strategy to work is that the stacked toxins bind to different binding ... | 2004 | 15006756 |
| the naturally derived insecticide spinosad is highly toxic to aedes and anopheles mosquito larvae. | spinosad is a naturally derived biorational insecticide with an environmentally favourable toxicity profile, so we investigated its potency against mosquito larvae (diptera: culicidae). by laboratory bioassays of a suspension concentrate formulation of spinosad (tracer), the 24 h lethal concentration (lc50) against aedes aegypti (l.) third and fourth instars was estimated at 0.025 p.p.m. following logit regression. the concentration-mortality response of third- and fourth-instar anopheles albima ... | 2004 | 15009445 |
| colloidal chitin stained with remazol brilliant blue r, a useful substrate to select chitinolytic microorganisms and to evaluate chitinases. | a simple and sensitive method based on the use of colloidal chitin stained with remazol brilliant blue r (rbb) is proposed to evaluate chitinase activity. if this colloidal-stained substrate is included as a carbon source in a liquid medium, this technique allows the selection or the comparison of chitinolytic microorganisms. the colloidal substrate is proportionally solubilized and the dye released is spectrophotometrically quantified at 595 nm. the procedures used for the staining and fixing o ... | 2004 | 14744450 |
| the bacillus thuringiensis cry1aa toxin: effects of trypsin and chymotrypsin site mutations on toxicity and stability. | the objective of the present work was to create an active cry1aa toxin showing enhanced resistance to degradation by spruce budworm (choristoneura fumiferana) midgut proteases by mutating potential chymotrypsin and trypsin sites. fourteen cry1aa mutants were created in an escherichia coli-bacillus shuttle vector and expressed in a crystal minus bacillus thuringiensis host. using spruce budworm gut juice, commercial bovine trypsin and chymotrypsin we performed protease resistance assays with cry1 ... | 2004 | 15050842 |
| evaluation of bt (bacillus thuringiensis) corn on mouse testicular development by dual parameter flow cytometry. | the health safety of bt (bacillus thuringiensis) corn (zea mays l.) was studied using mouse testes as a sensitive biomonitor of potential toxic effects. pregnant mice were fed a bt corn or a nontransgenic (conventional) diet during gestation and lactation. after they were weaned, young male mice were maintained on the respective diets. at 8, 16, 26, 32, 63, and 87 days after birth, three male mice and an adult reference mouse were killed, the testes were surgically removed, and the percentage of ... | 2004 | 15053558 |
| functional analysis of two processed fragments of bacillus thuringiensis cry11a toxin. | the 70-kda protoxin of cry11a, a dipteran-specific insecticidal protein, was processed by trypsin into 36- and 32-kda fragments. to investigate the potent function of the two processed fragments, a gst (glutathione-s-transferase) fusion protein of each polypeptide was constructed. while neither the 36- nor the 32-kda fragment was toxic to culex pipiens larvae, coexpression of the two fragments restored the insecticidal activity. furthermore, the coprecipitation experiment demonstrated that the 3 ... | 2004 | 15056882 |
| in vivo binding of the cry11bb toxin of bacillus thuringiensis subsp. medellin to the midgut of mosquito larvae (diptera: culicidae). | bacillus thuringiensis subsp. medellin produces numerous proteins among which 94 kda known as cry11bb, has mosquitocidal activity. the mode of action of the cry11 proteins has been described as similar to those of the cry1 toxins, nevertheless, the mechanism of action is still not clear. in this study we investigated the in vivo binding of the cry11bb toxin to the midgut of the insect species anopheles albimanus, aedes aegypti, and culex quinquefasciatus by immunohistochemical analysis. spodopte ... | 2004 | 15057351 |
| dissection of cry gene profiles of bacillus thuringiensis isolates in taiwan. | on the basis of the newly revised nomenclature system of cry genes, the pcr amplification method has been adopted to resolve the cry gene combinations of 294 bacillus thuringiensis isolates from five selected areas of taiwan. our results indicate that cry1 (especially cry1a + 1b + 1f) and cry2 were the most abundant cry genes in taiwan. in contrast, cry3 and cry6 genes were detected only on yang ming mountain, while the cry13 gene was found only on snow mountain. in addition, some distinctive co ... | 2004 | 15057451 |
| expression of chitinase-encoding genes in bacillus thuringiensis and toxicity of engineered b. thuringiensis subsp. aizawai toward lymantria dispar larvae. | chitinase genes from aeromonas hydrophila and bacillus circulans no.4.1 were cloned into the plasmid phy300plk and designated as phya2 and phyb43, respectively. both plasmids were introduced into various strains of b. thuringiensis by electroporation. plasmid phyb43 was generally structurally stable, but showed lower segregrational stability than phya2 in b. thuringiensis subsp. aizawai when grown under nonselective conditions. the production of chitinase from b. thuringiensis subsp. aizawai har ... | 2004 | 15057461 |
| endospore degradation in an oligosporogenic, crystalliferous mutant of bacillus thuringiensis. | we isolated a new oligosporogenic mutant from bacillus thuringiensis var. kurstaki hd73 that retains the ability to produce insecticidal crystal inclusions. sporulation in this mutant initiates in a manner similar to the wild-type strain, and under the electron microscope endospores are seen, but these do not reach maturity (except for 0.2% of them). at a late stage, the coat surrounding the forespore seems to lack shape and to be empty. most mutant cells exhibit a well-formed bipyramidal crysta ... | 2004 | 15057485 |
| expression and characterization of a recombinant cry1ac crystal protein with enhanced green fluorescent protein in acrystalliferous bacillus thuringiensis. | to investigate fusion expression between bacillus thuringiensis crystal protein and a foreign protein, the expression of a fusion protein comprised of cry1ac, and enhanced green fluorescent protein (egfp) in b. thuringiensis cry(-)b strain was examined. | 2004 | 15059210 |
| why bt cotton pays for small-scale producers in south africa. | 2004 | 15060543 | |
| enhanced expression of insecticidal crystal proteins in wild bacillus thuringiensis strains by a heterogeneous protein p20. | p20 is a small chaperone-like protein encoded by a cry11a operon in bacillus thuringiensis subsp. israelensis (bti); it is essential to cyt1aa expression. in this report, the gene p20 was transformed into wild strains of subsp. kurstaki to raise the yield of crystal proteins. as a result, larger crystals were produced by the transformant than by the wild control, and most were in the form of a big bipyramid (average 2.4 microm long); some were irregular because of too high expression, while the ... | 2004 | 15060726 |
| designing better probes: effect of probe size, mismatch position and number on hybridization in dna oligonucleotide microarrays. | dna microarrays represent a powerful technology whose use has been hampered by the uncertainty of whether the same principles, established on a scale typical for membrane hybridizations, apply when using the smaller, rigid support of microarrays. our goal was to understand how the number and position of base pair mismatches, probe length and their g+c content affect the intensity and specificity of the hybridization signal. one set of oligonucleotides (50-mers) based on three regions of the baci ... | 2004 | 15063067 |
| shared genetic basis of resistance to bt toxin cry1ac in independent strains of pink bollworm. | classical and molecular genetic analyses show that two independently derived resistant strains of pink bollworm, pectinophora gossypiella (saunders), share a genetic locus at which three mutant alleles confer resistance to bacillus thuringiensis (bt) toxin cry1ac. one laboratory-selected resistant strain (azp-r) was derived from individuals collected in 1997 from 10 arizona cotton fields, whereas the other (aphis-98r) was derived from a long-term susceptible laboratory strain. both strains were ... | 2004 | 15279243 |
| two new bacterial pathogens of colorado potato beetle coleoptera: chrysomelidae). | other than bacillus thuringiensis berliner, few bacteria are lethal to the colorado potato beetle (leptinotarsa decemlineata [say]), a major pest of potatoes and eggplant. expanded use of biologicals for the control of colorado potato beetle will improve resistance management, reduce pesticide use, and produce novel compounds for potential use in transgenic plants. using freeze-dried, rehydrated artificial diet in pellet form to screen bacteria lethal to other insects, we determined that strains ... | 2004 | 15279252 |
| role of egg density on establishment and plant-to-plant movement by western corn rootworm larvae (coleoptera: chrysomelidae). | the effect of egg density on establishment and dispersal of larvae of the western corn rootworm, diabrotica virgifera virgifera leconte, was evaluated in a 3-yr field study. implications of these data for resistance management plans for bt crops are discussed. viable egg levels of 100, 200, 400, 800, and 1600 eggs per infested plant were evaluated in 2000, 2001, and 2002. a 3200 viable egg level was also tested in 2001 and 2002. all eggs were infested on one plant per subplot in a field that was ... | 2004 | 15279266 |
| cross-resistance of cry1ab-selected ostrinia nubilalis (lepidoptera: crambidae) to bacillus thuringiensis delta-endotoxins. | corn plants expressing the toxin from bacillus thuringiensis (berliner) have proven to be effective in controlling lepidopteran pests such as the european corn borer, ostrinia nubilalis (hübner) (lepidoptera: crambidae). several bt toxins are being tested and incorporated into crop genomes, although tests for cross-resistance among different toxins have been limited by a lack of resistant colonies. four different colonies of o. nubilalis selected with full-length cry1ab incorporated into artific ... | 2004 | 15279290 |
| genetics of resistance to transgenic bacillus thuringiensis poplars in chrysomela tremulae (coleoptera: chrysomelidae). | the area under genetically engineered plants producing bacillus thuringiensis (bt) toxins is steadily increasing. this increase has magnified the risk of alleles conferring resistance to these toxins being selected in natural populations of target insect pests. the speed at which this selection is likely to occur depends on the genetic characteristics of bt resistance. we selected a strain of the beetle chrysomela tremulae fabricius on a transgenic bt poplar clone populus tremula l. x populus tr ... | 2004 | 15279291 |
| cloning and partial characterization of zwittermicin a resistance gene cluster from bacillus thuringiensis subsp. kurstaki strain hd1. | the study seeks to shed light on the aminopolyol, broad-spectrum antibiotic zwittermicin a gene cluster of bacillus thuringiensis subsp. kurstaki hd1 and to identify any new uncharacterized genes with an eventual goal to establish a better understanding of the resistance gene cluster. | 2004 | 15281929 |
| potentiation of insecticidal activity of bacillus thuringiensis subsp. kurstaki hd-1 by proteinase inhibitors in the american bollworm, helicoverpa armigera (hübner). | the effect of crude proteinase inhibitor extracts from seeds of different crop plants (black gram, chickpea, chickling vetch, finger millet, french bean, green gram, horse gram, lentil, pea and soybean) on the insecticidal activity of b. thuringiensis var. kurstaki hd-1 was investigated against neonate larvae of h. armigera by diet incorporation method. the larval mortality due to crude proteinase inhibitors alone (5% seed weight equivalent) ranged from 4.1 to 19.1%; the maximum mortality with f ... | 2004 | 15282948 |
| development and mechanisms of resistance to bacillus thuringiensis endotoxin cry1ac in the american bollworm, helicoverpa armigera (hübner). | the american bollworm, h. armigera, evolved 31-fold resistance to selection pressure of b. thuringiensis endotoxin cry1ac within six generations. the cry1ac selected larvae of h. armigera showed cross-resistance to cry1aa and cry1ab both in terms of mortality and growth reduction. studies on mechanisms of resistance to cry1ac showed that proteases of resistant insects degraded cry1ac faster than those of susceptible insects, which led to the relative unavailability of toxin of about 58 kda for b ... | 2004 | 15282949 |
| a rapid screening method for the detection of viable spores in powder using bioluminescence. | a rapid diagnosis of a biological threat in a powder sample is important for fi rst responders who have to make decisions on-site. the present culture-based method does not provide timely results, which is a critical barrier for a quick response when a suspicious powder sample is found. the atp bioluminescence method, combined with a heat shock, was investigated to determine the presence of spores in powder. the results show that only spore-containing powder samples provided a dramatic increase ... | 2004 | 15287006 |
| characterization of a novel plasma membrane protein, expressed in the midgut epithelia of bombyx mori, that binds to cry1a toxins. | we describe the properties of a novel 252-kda protein (p252) isolated from brush border membranes of bombyx mori. p252 was found in a triton x-100-soluble brush border membrane vesicle fraction, suggesting that it may be a component of the midgut epithelial cell membrane. p252 was purified to homogeneity, and the amino acid sequence of two internal peptides was determined, but neither of the peptides matched protein sequences in the available databases. the apparent molecular mass of the purifie ... | 2004 | 15294792 |
| characterization of two bacillus thuringiensis genes identified by in vivo screening of virulence factors. | bacillus thuringiensis vegetative cells are known to be highly pathogenic when injected into the hemocoel of susceptible insect larvae. this pathogenicity is due to the capacity of b. thuringiensis to cause septicemia in the host. we screened a b. thuringiensis mini-tn10 insertion library for loss of virulence against bombyx mori larvae on injection into the hemocoel. three clones with attenuated virulence were isolated, corresponding to two different mini-tn10 insertions mapping to the yqgb/yqf ... | 2004 | 15294815 |
| binary toxins from bacillus thuringiensis active against the western corn rootworm, diabrotica virgifera virgifera leconte. | the western corn rootworm, diabrotica virgifera virgifera leconte, is a significant pest of corn in the united states. the development of transgenic corn hybrids resistant to rootworm feeding damage depends on the identification of genes encoding insecticidal proteins toxic to rootworm larvae. in this study, a bioassay screen was used to identify several isolates of the bacterium bacillus thuringiensis active against rootworm. these bacterial isolates each produce distinct crystal proteins with ... | 2004 | 15294828 |
| signal peptide of potato pinii enhances the expression of cry1ac in transgenic tobacco. | the modified cry1ac was expressed in transgenic tobacco plants. to allow secretion of the cry1ac protein into the intercellular space, the signal peptide sequence of potato proteinase inhibitor ii (pinii) was n-terminally fused to the cry1ac encoding region. expression of cry1ac in transgenic tobacco plants was assayed with elisa. the results showed that pinii signal peptide sequence enhanced the expression of cry1ac protein and led to the secretion of the cry1ac protein in transgenic tobacco pl ... | 2004 | 15295648 |
| evaluation of sampling plans to detect cry9c protein in corn flour and meal. | starlink is a genetically modified corn that produces an insecticidal protein, cry9c. studies were conducted to determine the variability and cry9c distribution among sample test results when cry9c protein was estimated in a bulk lot of corn flour and meal. emphasis was placed on measuring sampling and analytical variances associated with each step of the test procedure used to measure cry9c in corn flour and meal. two commercially available enzyme-linked immunosorbent assay kits were used: one ... | 2004 | 15295890 |
| mics of selected antibiotics for bacillus anthracis, bacillus cereus, bacillus thuringiensis, and bacillus mycoides from a range of clinical and environmental sources as determined by the etest. | this paper presents etest determinations of mics of selected antimicrobial agents for 76 isolates of bacillus anthracis chosen for their diverse histories and 67, 12, and 4 cultures, respectively, of its close relatives b. cereus, b. thuringiensis, and b. mycoides derived from a range of clinical and environmental sources. nccls breakpoints are now available for b. anthracis and ciprofloxacin, penicillin, and tetracycline; based on these breakpoints, the b. anthracis isolates were all fully susc ... | 2004 | 15297508 |
| use of 16s rrna, 23s rrna, and gyrb gene sequence analysis to determine phylogenetic relationships of bacillus cereus group microorganisms. | in order to determine if variations in rrna sequence could be used for discrimination of the members of the bacillus cereus group, we analyzed 183 16s rrna and 74 23s rrna sequences for all species in the b. cereus group. we also analyzed 30 gyrb sequences for b. cereus group strains with published 16s rrna sequences. our findings indicated that the three most common species of the b. cereus group, b. cereus, bacillus thuringiensis, and bacillus mycoides, were each heterogeneous in all three gen ... | 2004 | 15297521 |
| competition of bacillus thuringiensis cry1 toxins for midgut binding sites: a basis for the development and management of transgenic tropical maize resistant to several stemborers. | binding and competition of five bacillus thuringiensis toxins--cry1ab, cry1ac, cry1ba, cry1ca, and cry1ea--for midgut binding sites from three pests, spodoptera frugiperda, diatraea saccharalis, and diatraea grandiosella, were investigated as part of a strategy to develop tropical transgenic maize resistant to several stemborers. on s. frugiperda, cry1ab and cry1ac compete for the same binding site; cry1ba and cry1ca compete for a second binding site. cry1ea recognizes a third specific binding s ... | 2004 | 15297925 |
| activity of bacillus thuringiensis toxins against cocoa pod borer larvae. | twelve cry proteins from bacillus thuringiensis berliner were tested in bioassays on cacao plantations in indonesia for activity against the larvae of cocoa pod borer (conopomorpha cramerella (snellen)), an insect pest of the cacao tree. through the damage caused by their feeding, the larvae of cocoa pod borer cause the pods of the cocoa tree to ripen prematurely. they are difficult to control with conventional measures. preliminary assays identified five toxins that were more active than others ... | 2004 | 15307664 |
| genetics of spinosad resistance in a multi-resistant field-selected population of plutella xylostella. | resistance to the bacteria-derived insecticides spinosad (conserve), abamectin (vertimec), bacillus thuringiensis var kurstaki (btk) (dipel), b thuringiensis var aizawai (bta) (xentari), b thuringiensis crystal endotoxins cry1ac and cry1ca, and to the synthetic insecticide fipronil was estimated in a freshly-collected field population (ch1 strain) of plutella xylostella (l) from the cameron highlands, malaysia. laboratory bioassays at g1 indicated significant levels of resistance to spinosad, ab ... | 2004 | 15307676 |
| biopesticides. | the term 'biopesticide' encompasses a broad array of microbial pesticides, biochemicals derived from micro-organisms and other natural sources, and processes involving the genetic incorporation of dna into agricultural commodities that confer protection against pest damage (plant-incorporated protectants). some microbial pesticides, such as bacillus thuringiensis, have a long history of safe and effective use as a biological insecticide. more recent developments in microbial pest control include ... | 2003 | 15071818 |
| [detection of genetic modification in maize and maize products by elisa-test]. | enzyme immunoassay methods--trait test--was applied for detection of genetic modification in maize seeds and foodstuffs, which have been produced from this crop. trait test is based on the identification gmo protein cry 1ab produced by a gene derived from bacillus thuringiensis (bt) incorporated into insect resistant corn grain. the experiment was carried out on maize standards and foodstuffs from warsaw market. the positive result was obtained for one maize product, which was not labelled as gm ... | 2003 | 15052732 |
| occurrence and linkage between secreted insecticidal toxins in natural isolates of bacillus thuringiensis. | little is known about the occurrence and linkage between secreted insecticidal virulence factors in natural populations of bacillus thuringiensis (bt). we carried out a survey of 392 bt strains isolated from various samples originating from 31 countries. the toxicity profile of the culture supernatants of these strains was determined individually against anthonomus grandis (coleoptera) and spodoptera littoralis (lepidoptera). we analyzed beta-exotoxin i production and searched for the genes enco ... | 2003 | 14756535 |
| [effect of transgenic bt rice planting on soil enzyme activities]. | a pot experiment was conducted with silty loam agrodolf as test soil and with transgenic bt rice and non-bt rice as test crops to study the effect of transgenic bt rice planting on soil urease, phophatase, arylsulfatase, invertase, and dehydrogenase activities. the results showed that bt toxin could be introduced into soil through root exudates of transgenic bt rice, and its survival amount in soil varied with time. compared with non-bt rice treatment, transgenic bt rice treatment had a signific ... | 2003 | 15031930 |
| aerosols from insect control measures show dangers of bioterrorism. | 2003 | 15040200 | |
| [advances in safety studies of soil bt toxin proteins released from transgenic bt crops]. | commercialized transgenic bt (bacillus thuringiensis) crops are permitted for field growth in a large scale, which leads to significant issues of ecological risk assessment in soil ecosystem. in this paper, some general safety problems involving in the soil bt active toxins released from insect-resistant transgenic bt crops in the forms of plant residues, root exudates and pollens were reviewed, including their adsorption by soil active-particles, their insecticidal activity, persistence, and bi ... | 2003 | 14997678 |
| lethal and sublethal effects of single and double applications of bacillus thuringiensis variety kurstaki on spruce budworm (lepidoptera: tortricidae) larvae. | we conducted laboratory experiments to examine the effects of single versus double exposures of spruce budworm, choristoneura fumiferana (lepidoptera: tortricidae) female larvae to various concentrations of a bacillus thuringiensis variety kurstaki (btk) commercial formulation (foray 48b). our main objective was to document the vulnerability to btk and the sublethal responses of fifth-instar larvae that survived from a first ingestion of btk during their fourth stadium and to compare them with i ... | 2003 | 14994791 |
| preparation of spray-dried wettable powder formulations of bacillus thuringiensis-based biopesticides. | bacillus thuringiensis is the most widely used biopesticide among many methods available to control insects. to make a saleable product, b. thuringiensis must be substantially concentrated by removal of water and formulated to improve longevity, efficacy, and ease of transport of the product. b. thuringiensis subsp. aizawai culture broth as an active ingredient was mixed with various adjuvants and then spray dried. the optimum conditions for spray drying were found to be an outlet temperature of ... | 2003 | 14994793 |
| design and evaluation of an aerial spray trial with true replicates to test the efficacy of bacillus thuringiensis insecticide in a boreal forest. | a field trial using true replicates was conducted successfully in a boreal forest in 1996 to evaluate the efficacy of two aerially applied bacillus thuringiensis formulations, abg 6429 and abg 6430. a complete randomized design with four replicates per treatment was chosen. twelve to 15 balsam fir (abies balsamea [l.] mill.) per plot were randomly selected as sample trees. interplot buffer zones, > or = 200 m wide, adequately prevented cross contamination from sprays that were atomized with four ... | 2003 | 14994805 |
| laboratory and field evaluation of tebufenozide, diflubenzuron, and bacillus thurengiensis var. kurstaki for suppression of douglas-fir tussock moth (orgyia pseudotsugata (mcdunnough)) in idaho: a case study. | the insect growth regulator tebufenozide (mimic 2lv) was tested to examine its impact on the douglas-fir tussock moth, orgyia pseudotsugata (mcdunnough) (lepidoptera: lymantriidae). laboratory tests gave an estimated concentration of 1.26 ppm of the compound to achieve 50% population mortality (lc50) for second-instar o. pseudotsugata. at the highest concentration tested, tebufenozide resulted in significant larval mortality within 7 d with an estimated time to 50% population mortality (lt50) of ... | 2003 | 14994806 |
| evaluation of oils and microbial pathogens for control of lepidopteran pests of sweet corn in new england. | vegetable and mineral oil, beauveria bassiana (balsamo) and bacillus thuringiensis subsp. kurstaki berliner were evaluated for control of ostrinia nubilalis (hübner) (lepidoptera: pyralidae), helicoverpa zea (boddie) (lepidoptera: noctuidae) and spodoptera frugiperda (j. e. smith) (lepidoptera: noctuidae) in sweet corn (zea mays l.). field experiments in maine and massachusetts during 1993 and 1994 evaluated oils and pathogens singly or in combinations, using a single application directly to the ... | 2003 | 14977100 |
| increased mortality of gypsy moth lymantria dispar (l.) (lepidoptera: lymantriidae) exposed to gypsy moth nuclear polyhedrosis virus in combination with the phenolic gycoside salicin. | second instar gypsy moth, lymantria dispar (l.) (lepidoptera: lymantriidae), larvae suffered significantly greater mortality from aerially applied gypsy moth nuclear polyhedrosis virus (gypchek) when the virus was consumed on quaking aspen, populus tremuloides michx., versus red oak, quercus spp. l., foliage. laboratory assays in which various doses of gypchek and salicin (a phenolic glycoside present in aspen foliage) were tested in combination demonstrated that salicin significantly increased ... | 2003 | 14977101 |
| use of transgenic plants to measure insect herbivore movement. | use of ingested transgenic corn tissue as a marker for measuring movement of adult diabrotica virgifera virgifera (leconte) (coleoptera: chrysomelidae; western corn rootworm) was investigated. laboratory observations of beetles feeding on corn foliage, pollen, silks, or soybean foliage provided background on feeding patterns. the interval between food consumption and its appearance in feces (gut passage time) ranged from 102.7 +/- 11 min for soybean foliage to 56.7 +/- 2.9 min for corn silks. in ... | 2003 | 14977111 |
| efficacy of vectobac (bacillus thuringiensis variety israelensis) formulations for mosquito control in australia. | laboratory bioassays were conducted on the efficacy of a water-dispersible granule (wg) formulation of bacillus thuringiensis variety israelensis (vectobac wg; active ingredient [ai]: 3,000 bti international toxic units [itu]/mg) against third instars of six common australian mosquito species, aedes aegypti (l.), ochlerotatus vigilax (skuse), ochlerotatus notoscriptus (skuse), culex sitiens wiedemann, culex annulirostris skuse, and culex quinquefasciatus say. the normal model for log-linear mort ... | 2003 | 14977116 |
| geographic variation in susceptibility of chilo suppressalis (lepidoptera: pyralidae) to bacillus thuringiensis toxins in china. | geographic variation in the susceptibility of the striped stem borer, chilo suppressalis (walker) (lepidoptera: pyralidae), in china to bacillus thuringiensis (bt) insecticidal crystal proteins cry1ac and cry1ab was studied to establish baseline information for comparing the future response of populations with increased exposure to bt products. rice is the major host of c. suppressalis, and bt rice ma) be released in china in the near future. twelve populations of the pest were collected from th ... | 2003 | 14977124 |
| review of blackfly (diptera: simuliidae) control in south africa. | the medical, veterinary and economic importance of blackflies in south africa, and the historical development of blackfly control programmes in various south african rivers, are reviewed in this paper. in 1996 it was estimated that blackflies can cause more than r 88 million damages per annum along the middle and lower orange river where simulium chutteri is considered the main pest species. a clear link between the construction of dams and the spread of the blackfly problem was shown. four phas ... | 2003 | 14971733 |
| soil characteristics as factors governing the existence, recycling and persistence of bacillus thuringiensis in egypt. | the simple correlation and regression analyses showed that the soil sand percentage and the available copper levels had significant negative and positive contributions, respectively, to the abundance and distribution of b. thuringiensis in the egyptian agricultural soil. among the b. thuringiensis isolates, only 11.26% of strains showed larvicidal activity against culex pipiens. the larvicidal potency ld50 varied from 5.01x10(5) to 5.4x10(6) spores per milliliter among the isolates. | 2003 | 14964648 |
| detection of transgenic and endogenous plant dna in rumen fluid, duodenal digesta, milk, blood, and feces of lactating dairy cows. | the objective was to determine the presence or absence of transgenic and endogenous plant dna in ruminal fluid, duodenal digesta, milk, blood, and feces, and if found, to determine fragment size. six multiparous lactating holstein cows fitted with ruminal and duodenal cannulas received a total mixed ration. there were two treatments (t). in t1, the concentrate contained genetically modified (gm) soybean meal (cp4epsps gene) and gm corn grain (cry1a[b] gene), whereas t2 contained the near isogeni ... | 2003 | 14740846 |
| comparative delta-endotoxins of bacillus thuringiensis against mosquito vectors (aedes aegypti and culex pipiens). | pure crystals of seven bacillus thuringiensis field isolates from the lower silesia region (poland) were tested against larvae of aedes aegypti l. and culex pipiens l. (culicidae, diptera). the crystals of opq3 phylloplane isolate (belonging to the first biochemical type of b. thuringiensis subsp. japonensis, yoso, jinghongiensis) killed from 68 +/- 7% to 84 +/- 7% of the fourth instar larvae of a. aegypti. the crystals of two other strains (kpf3 and kpc1) of this group caused mortality between ... | 2003 | 14743982 |
| analysis of the properties of bacillus thuringiensis insecticidal toxins using a potential-sensitive fluorescent probe. | a potential-sensitive fluorescent probe, 3,3'-dipropylthiadicarbocyanine iodide, was used to analyze, at ph 7.5 and 10.5, the effects of bacillus thuringiensis toxins on the membrane potential generated by the efflux of k(+) ions from brush border membrane vesicles purified from the midgut of the tobacco hornworm, manduca sexta. fluorescence levels were strongly influenced by the ph and ionic strength of the media. therefore, characterization of the effects of the toxins was conducted at constan ... | 2003 | 14724756 |
| [displaying polyhistidine peptide on the cell surface of bacillus thuringiensis by s-layer protein]. | cell surface layer (s-layer) is the outmost structure of bacterium cell and covers the intact cell. s-layer protein of bacillus thuringiensis strain ctc (ctc protein) was used as carrier protein to display polyhistidine (polyhis) peptides on the cell surface. series fusion protein genes were constructed by inserting dna fragments encoding (6his)1, (6his)2, (6his)3, (6his)9 and (6his)15 polyhis peptides into ctc protein gene at the site of downstream of slh domain. with the help of recombinant pl ... | 2003 | 14724939 |
| comparison of broiler performance when fed diets containing grain from yieldgard rootworm (mon863), yieldgard plus (mon810 x mon863), nontransgenic control, or commercial reference corn hybrids. | two 42-d experiments compared the nutritional value of yieldgard rootworm corn (mon863; experiment 1) and yieldgard plus corn (mon810 x mon863; experiment 2) to their respective nontransgenic controls and 6 commercial reference corn hybrids when fed to growing broilers. for each experiment, a randomized complete block design was used with 8 dietary treatments in each of 5 replicated blocks of pens. in experiment 1, no differences among diets were observed (p > 0.05) for final live weights and fe ... | 2003 | 14717553 |
| the action of cu2+ on bacillus thuringiensis growth investigated by microcalorimetry. | by using an lkb-2277 bioactivity monitor, ampoule mode, the heat output of bacillus thuringiensis growth metabolism has been determined at 28 degrees c and effect of cu2+ on b. thuringiensis growth was studied. copper has been regarded as an essential trace element for life. its deficiency may be the cause of diseases. cu2+ of different concentration have different effects on b. thuringiensis growth metabolism, cu2+ of low concentration (0-30 micrograms/ml) can promote the growth of b. thuringie ... | 2003 | 14714479 |
| development and use of an elisa test to detect ige antibody to cry9c following possible exposure to bioengineered corn. | starlink(tm), a variety of corn genetically engineered to contain the insecticidal protein cry9c, had not been approved for human consumption because it possessed some characteristics associated with allergenic proteins. however, in the fall of 2000 cry9c dna was detected in several corn-containing products, suggesting that starlink corn had entered the human food supply. subsequently, consumers, following consumption of corn products, reported a number of adverse health events, possibly consist ... | 2003 | 14707463 |
| a semifield evaluation of vectobac dt (abg-6499), a new formulation of bacillus thuringiensis israelensis for control of aedes albopictus. | we evaluated the effectiveness and duration of effectiveness of a new formulation of bacillus thuringiensis var. israelensis (bti) for control of larval aedes albopictus. the product tested was vectobac dt (abg-6499), a bti tablet formulation containing 3.4% of active ingredient (3,400 itu/mg) supplied by scae valent biosciences italy s.r.l. the study was conducted at the botanical garden of the university of rome "la sapienza" between june and september 2002, the most favorable season for the d ... | 2003 | 14710747 |
| maldi analysis of bacilli in spore mixtures by applying a quadrupole ion trap time-of-flight tandem mass spectrometer. | a novel ion trap time-of-flight hybrid mass spectrometer (qit-tof ms) has been applied for peptide sequencing in proteolytic digests generated from spore mixtures of bacilli. the method of on-probe solubilization and in situ proteolytic digestion of small, acid-soluble spore proteins has been recently developed in our laboratory, and microorganism identification in less than 20 min was accomplished. in this study, tryptic peptides were generated in situ from complex spore mixtures of b. subtilis ... | 2003 | 14710845 |
| characterization of bacillus spore species and their mixtures using postsource decay with a curved-field reflectron. | a strategy is proposed for the rapid identification of bacillus spores, which relies on the selective release of a family of proteins, referred to as small, acid-soluble spore proteins (sasps). in this work, sasps were selectively solubilized from bacillus spores on the maldi sample plate by using 10% tfa. proteolytic digests of sasps generated in situ from spores of b. subtilis 168, b. globigii, b. thuringiensis subs. kurstaki hd-1, b. cereus t, and the nonpathogenic strain b. anthracis sterne ... | 2003 | 14710846 |
| sequencing and characterization of plasmid puibi-1 from bacillus thuringiensis serovar entomocidus lbit-113. | plasmid puibi-1 from bacillus thuringiensis svr. entomocidus was sequenced and its replication mechanism analyzed. sequence analysis revealed that puibi-1 contains 4671 bp and a 32% gc content. plasmid puibi-1 also includes at least seven putative open reading frames (orfs) encoding for proteins ranging from 5 to 50 kda. orf-1 encodes for a putative 16-kda rep protein, which lacks homology with proteins of similar function. orf2 encodes for a protein of 50 kda and shows homology with mob protein ... | 2003 | 14669916 |
| distribution analysis of is231-like sequences among bacillus thuringiensis serovars inferred from restriction fragment length polymorphisms. | the distribution of is231 has been analyzed in bacillus thuringiensis serovars. a 723-bp haeii conserved fragment from is231m has been used as a probe against ecori-digested b. thuringiensis total dna to yield serovar-specific hybridization profiles. the approach was useful at revealing the extent of distribution of is231-like sequences between and within strains. of the 88 b. thuringiensis strains tested, 70 showed hybridization banding patterns that comprised between one and 20 distinct bands. ... | 2003 | 14669921 |
| [on the adaptive nature of the dissociation process in bacillus thuringiensis]. | the process of dissociation into variants differing in colony morphology occurring in batch cloned cultures of two bacillus thuringiensis strains belonging to different subspecies was studied at optimal and elevated temperatures. an increase in the cultivation temperature to 40 degrees c resulted in an increase in the fraction of r variants to 100% after 72 h of cultivation of either of the strains. this increase was not due to the selection of forms with greater resistance to elevated temperatu ... | 2003 | 14679909 |
| the ispa protease's involvement in the regulation of the sporulation process of bacillus thuringiensis is revealed by proteomic analysis. | we have observed that the process of sporulation of the ispa-deficient mutant was delayed under phase-contrast microscopy. the protein profiles of the ispa-deficient mutant have been analyzed using two-dimensional gel electrophoresis. the results of a proteomic analysis using maldi-tof ms indicated that a sporulation-associated protein, pro- [formula: see text], was upregulated, while two other sporulation-associated proteins, spovd and spovr, were downregulated in the ispa-deficient mutant. it ... | 2003 | 14680823 |
| [construction of insecticidal recombinant bacillus thuringiensis using an integrative vector]. | insecticidal crystal protein gene cry1c which is highly toxic to spodoptera exigua was cloned into an integrative vector pbmb-f7e, which was derived from bacillus thuringiensis transposon tn4430. the recombinant integrative plasmid pbmb-flc harboring the cry1c gene was gained and transformed into a wild-type bt strain ybt803-1. a transformant bmb803-a was obtained, and grown at 46 degrees c for about 120 generations, from which three recombinants with cry1c gene integrating into the chromosome w ... | 2003 | 14682242 |
| leaf ontogeny influences leaf phenolics and the efficacy of genetically expressed bacillus thuringiensis cry1a(a) d-endotoxin in hybrid poplar against gypsy moth. | we tested the hypothesis that ontogenetic variation in leaf chemistry could affect the efficacy of genetically expressed bacillus thuringiensis cry1a(a) d-endotoxin, and thus provide spatial variation in (1) foliage protection and (2) selective pressures that could delay the resistance of folivores. our model consisted of clonal hybrid populus plants (nc5339). consumption of foliage and relative growth rates of gypsy moth, lymantria dispar (l.) increased, and phenolic glycoside concentrations de ... | 2003 | 14682535 |
| production of biopesticides using wastewater sludge as a raw material--effect of process parameters. | production of bacillus thuringiensis (bt) based biopesticide was studied using hydrolysed or raw wastewater sludge as a raw material. the sludge hydrolysis was carried out at different ph (2, 4 and 6). the sludge after hydrolysis was sterilised at 121 degrees c for 30 minutes. the effect of temperature, ph and agitation speed on growth and toxin production was also investigated. the ph in the shake flask was controlled by adding 0.1 m tris buffer. the progress of the biopesticide production proc ... | 2003 | 14682592 |
| identification of bacterial spores using statistical analysis of fourier transform infrared photoacoustic spectroscopy data. | fourier transform infrared photoacoustic spectroscopy (ftir-pas) has been applied for the first time to the identification and speciation of bacterial spores. a total of forty specimens representing five strains of bacillus spores (bacillus subtilis atcc 49760, bacillus atrophaeus atcc 49337, bacillus subtilis 6051, bacillus thuringiensis subsp. kurstaki, and bacillus globigii dugway) were analyzed. spores were deposited, with minimal preparation, into the photoacoustic sample cup and their spec ... | 2003 | 14661830 |
| compaction of the escherichia coli nucleoid caused by cyt1aa. | compaction of the escherichia coli nucleoid in the cell's centre was associated with the loss of colony-forming ability; these effects were caused by induction of cyt1aa, the cytotoxic 27 kda protein from bacillus thuringiensis subsp. israelensis. cyt1aa-affected compaction of the nucleoids was delayed but eventually more intense than compaction caused by chloramphenicol. the possibility that small, compact nucleoids in cyt1aa-expressing cells resulted in dna replication run-out and segregation ... | 2003 | 14663087 |
| effect of sm(3+) ion on growth of bacillus thuringiensis by microcalorimetry. | by using an lkb-2277 bioactivity monitor, cycle-flow method, the thermogenic curves of aerobic growth for bacillus thuringiensis cry ii strain at 28 degrees c have been obtained. the metabolic thermogenic curves of b. thuringiensis cry ii contained two distinct patterns: the first reflects the changes during the bacterial growth phase and the second corresponds to the sporulation phase. from these thermogenic curves in the absence and presence of sm(3+) ions, the thermokinetic parameters such as ... | 2003 | 14665732 |
| [potential of bacillus thuringiensis israelensis berliner for controlling aedes aegypti]. | the importance of the entomopathogenic bacterium bacillus thuringiensis israelensis in the control of aedes aegypti is presented. the use and potential of b. thuringiensis israelensis against the mosquito vector of dengue fever is described. other aspects such as insect's resistance development against chemicals and advantages and constraints of using microbial control are discussed. emphasis is given to the importance of the use of this bacterium in brazil, which could contribute significantly ... | 2003 | 14666315 |
| effect of food processing on the fate of dna with regard to degradation and transformation capability in bacillus subtilis. | soymilk, tofu, corn masa, and cooked potato were produced from transgenic raw materials and the effect of processing on the degradation of dna was studied. major degrading factors were for soymilk and tofu the mechanical treatment of soaked soybeans and for corn masa and cooked potatoes the thermal treatment. in the processed foods no dna fragments > 1.1 kb were detected. we included in our studies the effect of the size of donor dna and length of the homologous sequence on the marker rescue tra ... | 2003 | 14666975 |
| cry29a and cry30a: two novel delta-endotoxins isolated from bacillus thuringiensis serovar medellin. | two novel crystal protein genes from a highly mosquitocidal bacillus thuringiensis serovar medellin strain were cloned and sequenced. the corresponding proteins, cry29a and cry30a, were nontoxic when tested individually against the mosquito species bioassayed (aedes aegypti, culex pipiens and anopheles stephensi). however, cry29a synergized the toxicity of cry11bb against aedes aegypti by a four-fold factor. | 2003 | 14666976 |
| bt-resistance management--theory meets data. | 2003 | 14647327 | |
| spatial and temporal patterns of green fluorescent protein (gfp) fluorescence during leaf canopy development in transgenic oilseed rape, brassica napus l. | the green fluorescent protein (gfp) holds promise as a field-level transgene marker. one obstacle to the use of gfp is fluorescence variability observed within leaf canopies. in growth chamber and field experiments, gfp fluorescence in transgenic oilseed rape ( brassica napus) was shown to be variable at each leaf position over time and among different leaves on the same plant. a leaf had its highest gfp fluorescence after emergence and, subsequently, its fluorescence intensity decreased. gfp fl ... | 2003 | 14648109 |
| fed-batch culture of bacillus thuringiensis based on motile intensity. | the operation of a fed-batch culture is more complicated than that of batch or continuous culture. thus, an appropriate feeding strategy for fed-batch cultures should be carefully designed. in this study, a simple feeding strategy for fed-batch culture of bacillus thuringiensis based on "motile intensity" is described. the feeding strategy consisted of two steps: (1) initiating feeding at the peak of motile intensity; (2) terminating feeding at low motile intensity (or non-motility) of the cells ... | 2003 | 14648344 |
| overwintering of heliothis virescens (f.) and helicoverpa zea (boddie) (lepidoptera: noctuidae) in cotton fields of northeast mississippi. | following the 1995-2001 crop seasons, population densities of pupae of tobacco budworm, heliothis virescens (f.), and corn earworm, helicoverpa zea (boddie), overwintering in cotton fields, gossypium hirsutum l., in monroe county, ms, were estimated by digging a total of 43,542 m-row. densities of pupae varied greatly among years with the highest densities occurring in years with low rainfall in the late summer and early fall. the sex ratio of pupae was variable and significantly male-biased in ... | 2003 | 14650516 |
| susceptibility profile of culex quinquefasciatus (diptera: culicidae) to bacillus sphaericus on selection with rotation and mixture of b. sphaericus and b. thuringiensis israelensis. | several strains of bacillus sphaericus (neide) (bsph), a spore-forming bacterium that produces potent mosquitocidal toxins, have been widely used against mosquito larvae globally. in some locations in the field and in the laboratory, moderate to high levels of resistance in culex pipiens complex mosquito larvae to bsph have been reported. practical strategies for dealing with the resistance problem and more importantly to delay or possibly prevent development of resistance to bsph in the first p ... | 2003 | 14596281 |
| detection of corn intrinsic and recombinant dna fragments and cry1ab protein in the gastrointestinal contents of pigs fed genetically modified corn bt11. | genetically modified corn has been approved as an animal feed in several countries, but information about the fate of genetically modified dna and protein in vivo is insufficient. genetically modified corn bt11 is developed by inserting a recombinant dna sequence encoding insecticidal cry1ab protein from bacillus thuringiensis subsp. kurstaki. we examined the presence of corn intrinsic and recombinant cry1ab gene by pcr, and the cry1ab protein by immunological tests in the gastrointestinal conte ... | 2003 | 14552382 |
| transgenic plants expressing two bacillus thuringiensis toxins delay insect resistance evolution. | preventing insect pests from developing resistance to bacillus thuringiensis (bt) toxins produced by transgenic crops is a major challenge for agriculture. theoretical models suggest that plants containing two dissimilar bt toxin genes ('pyramided' plants) have the potential to delay resistance more effectively than single-toxin plants used sequentially or in mosaics. to test these predictions, we developed a unique model system consisting of bt transgenic broccoli plants and the diamondback mot ... | 2003 | 14608363 |
| rapid evolution and the cost of resistance to bacillus thuringiensis in greenhouse populations of cabbage loopers, trichoplusia ni. | the microbial insecticide bacillus thuringiensis (bt) has become the mainstay of non-chemical control of lepidopteran pests, either as sprays or through the incorporation of bt toxins into transgenic crops. given the wide use of bt, it is striking that currently only one pest species, plutella xylostella, has been reported to have developed significant resistance to bt outside the laboratory. by contrast, we report here the frequent and rapid development of resistance to b. thuringiensis kurstak ... | 2003 | 14613613 |
| the bacillus thuringiensis linear double-stranded dna phage bam35, which is highly similar to the bacillus cereus linear plasmid pbclin15, has a prophage state. | bam35, a 15-kbp double-stranded dna phage, infects bacillus thuringiensis. recently, sequencing of the related bacillus cereus revealed a 15.1-kbp linear plasmid, pbclin15. we show that pbclin15 closely resembles bam35 and demonstrate conversion of bam35 to a prophage. this state is common, as several b. thuringiensis strains release bam35-related viruses. | 2003 | 14617663 |
| inheritance of resistance to bt canola in a field-derived population of plutella xylostella. | crops expressing bacillus thuringiensis (bt) insecticidal cry proteins are grown on millions of hectares. recommendations to delay resistance are based on a high expression/refugia strategy that aims to kill resistant heterozygotes and enable some susceptible insects to survive. leaf-dip bioassays on f1 crosses of malaysian populations of diamondback moth (plutella xylostella (l)) showed that crylac resistance was not fully recessive. the survival of ca 50% of heterozygotes on bt canola (brassic ... | 2003 | 14620045 |