Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| long-term evaluation of compliance with refuge requirements for bt cotton. | the success of the refuge strategy for delaying pest resistance to bt crops depends on compliance by farmers. however, the accuracy of previous estimates of compliance has been questioned. we have applied a novel approach based on the use of geographical information system (gis) technology to measure compliance with refuge requirements for bt cotton in six arizona regions from 1998 to 2003. although compliance varied among regions, overall compliance was above 88% in five of six years. with the ... | 2005 | 15714465 |
| validation of a cotton-specific gene, sad1, used as an endogenous reference gene in qualitative and real-time quantitative pcr detection of transgenic cottons. | genetically modified (gm) cotton lines have been approved for commercialization and widely cultivated in many countries, especially in china. as a step towards the development of reliable qualitative and quantitative pcr methods for detecting gm cottons, we report here the validation of the cotton (gossypium hirsutum) endogenous reference control gene, sad1, using conventional and real-time (rt)-pcr methods. both methods were tested on 15 different g. hirsutum cultivars, and identical amplicons ... | 2005 | 15726375 |
| persistence of vectobac wdg and metoprag s-2g against aedes aegypti larvae using a semi-field bioassay in rio de janeiro, brazil. | persistence of bacillus thuringiensis var. israelensis (vectobac wdg) and methoprene (metoprag s-2g) was evaluated against aedes aegypti late third instar larvae of the rockefeller strain in a semi-field bioassay. tests were performed in rio de janeiro, using containers made of plastic, iron, concrete and asbestos, placed in a shaded area. the formulations used were 0.2 g of vectobac-wdg and 1 g of metoprag s-2g per 100 liters of water in house storage containers. vectobac wdg was tested twice, ... | 2005 | 15729468 |
| degradation of cry1ab protein from genetically modified maize in the bovine gastrointestinal tract. | immunoblotting assays using commercial antibodies were established to investigate the unexpected persistence of the immunoactive cry1ab protein in the bovine gastrointestinal tract (git) previously suggested by enzyme-linked immunosorbent assay (elisa). samples of two different feeding experiments in cattle were analyzed with both elisa and immunoblotting methods. whereas results obtained by elisa suggested that the concentration of the cry1ab protein increased during the git passage, the immuno ... | 2005 | 15740023 |
| gil16, a new gram-positive tectiviral phage related to the bacillus thuringiensis gil01 and the bacillus cereus pbclin15 elements. | one of the most notable characteristics of tectiviridae resides in their double-layer coats: the double-stranded dna is located within a flexible lipoprotein vesicle covered by a rigid protein capsid. despite their apparent rarity, tectiviruses have an extremely wide distribution compared to other phage groups. members of this family have been found to infect gram-negative (prd1 and relatives) as well as gram-positive (bam35, gil01, ap50, and phins11) hosts. several reports have shown that tecti ... | 2005 | 15743944 |
| fingerprinting of bacillus thuringiensis type strains and isolates by using bacillus cereus group-specific repetitive extragenic palindromic sequence-based pcr analysis. | a total of 119 bacillus thuringiensis strains (83 type strains and 26 native isolates), as well as five b. cereus group species, were analyzed by repetitive extragenic palindromic sequence-based pcr analysis (rep-pcr) fingerprinting. primers bc-rep-1 and bc-rep-2 were specifically designed according to an extragenic 26-bp repeated sequence found in the six b. cereus group genomes reported. a total of 47 polymorphic bands were detected, and the patterns varied from 5 to 13 bands in number and fro ... | 2005 | 15746337 |
| quantitative molecular assay for fingerprinting microbial communities of wastewater and estrogen-degrading consortia. | a quantitative fingerprinting method, called the real-time terminal restriction fragment length polymorphism (real-time-t-rflp) assay, was developed for simultaneous determination of microbial diversity and abundance within a complex community. the real-time-t-rflp assay was developed by incorporating the quantitative feature of real-time pcr and the fingerprinting feature of t-rflp analysis. the assay was validated by using a model microbial community containing three pure strains, an escherich ... | 2005 | 15746346 |
| improvement of bioinsecticides production through adaptation of bacillus thuringiensis cells to heat treatment and nacl addition. | the present work aimed to increase yields of delta-endotoxin production through adaptation of bacillus thuringiensis cells to heat shock and sodium chloride and to investigate their involvements in bioinsecticides production improvement. | 2005 | 15752327 |
| purification, amino acid sequence and characterization of bacthuricin f4, a new bacteriocin produced by bacillus thuringiensis. | purification and characterization of a new bacteriocin, bacthuricin f4 of bacillus thuringiensis. | 2005 | 15752334 |
| glycolipids as receptors for bacillus thuringiensis crystal toxin. | the development of pest resistance threatens the effectiveness of bacillus thuringiensis (bt) toxins used in transgenic and organic farming. here, we demonstrate that (i) the major mechanism for bt toxin resistance in caenorhabditis elegans entails a loss of glycolipid carbohydrates; (ii) bt toxin directly and specifically binds glycolipids; and (iii) this binding is carbohydrate-dependent and relevant for toxin action in vivo. these carbohydrates contain the arthroseries core conserved in insec ... | 2005 | 15705852 |
| the cry3aa gene of bacillus thuringiensis bt886 encodes a toxin against long-horned beetles. | this report describes the identification of a new toxigenic strain of bacillus thuringiensis specific for long-horned beetles. b. thuringiensis bt866 encodes a cry3aa-like gene (bt886cry3aa) that is 1,956 bp in length and is predicted to encode an 85.78-kda protein. the gene is highly similar to cry3aa1, differing in only six nucleotides and four amino acids. the four disparate amino acids occur within the conserved domains of the cry3aa toxin. the expression of bt866cry3a in escherichia coli ce ... | 2005 | 15647932 |
| new strategy for identification of novel cry-type genes from bacillus thuringiensis strains. | we designed five degenerate primers for detection of novel cry genes from bacillus thuringiensis strains. an efficient strategy was developed based on a two-step pcr approach with these primers in five pair combinations. in the first step, only one of the primer pairs is used in the pcr, which allows amplification of dna fragments encoding protein regions that include consensus domains of representative proteins belonging to different cry groups. a second pcr is performed by using the first-step ... | 2005 | 15691928 |
| disruption of a cadherin gene associated with resistance to cry1ac {delta}-endotoxin of bacillus thuringiensis in helicoverpa armigera. | a laboratory strain (gy) of helicoverpa armigera (hubner) was established from surviving larvae collected from transgenic cotton expressing a bacillus thuringiensis var. kurstaki insecticidal protein (bt cotton) in gaoyang county, hebei province, people's republic of china, in 2001. the gybt strain was derived from the gy strain through 28 generations of selection with activated cry1ac delivered by diet surface contamination. when resistance to cry1ac in the gybt strain increased to 564-fold aft ... | 2005 | 15691952 |
| indian bt gene monoculture, potential time bomb. | 2005 | 15696133 | |
| potentiation and cellular phenotypes of the insecticidal toxin complexes of photorhabdus bacteria. | the toxin complex (tc) genes of bacteria comprise a large and growing family whose mode of action remains obscure. in the insect pathogen photorhabdus, tc genes encode high molecular weight insecticidal toxins with oral activity against caterpillar pests. one protein, tcda, has recently been expressed in transgenic plants and shown to confer insect resistance. these toxins therefore represent alternatives to toxins from bacillus thuringiensis (bt) for deployment in transgenic crops. levels of tc ... | 2005 | 15679840 |
| sequence variation in the cadherin gene of ostrinia nubilalis: a tool for field monitoring. | toxin-binding proteins of insect midgut epithelial cells are associated with insect resistance to bacillus thuringiensis (bt) cry toxins. a 5378 nt cdna encoding a 1717 amino acid putative midgut cadherin-like glycoprotein and candidate cry1ab toxin-binding protein was characterized from ostrinia nubilalis. intraspecific alignment of partial o. nubilalis cadherin gene sequences identified variance within proposed cry1a toxin binding region 2 (tbr2), 1328iplqtsilvvt[i/v] n1340, and flanking cry1a ... | 2005 | 15681223 |
| cellular fatty-acid analysis of bacillus thuringiensis var. kurstaki commercial preparations. | cellular fatty acid (cfa) composition of bacillus thuringiensis var. kurstaki (btk) preparations was determined by use of the midi sherlock microbial identification system on a hewlett-packard 5890 gas chromatograph. four commercial preparations--one btk sample obtained from the u.s. forest service, one btk sample obtained from dugway proving ground, and btk and bacillus thuringiensis var. israelensis (bti) preparations obtained from american type culture collection (atcc)--were analyzed and eva ... | 2005 | 15686395 |
| isolation, characterization and expression of a novel vegetative insecticidal protein gene of bacillus thuringiensis. | twenty-four serovars of bacillus thuringiensis (bt) were screened by polymerase chain reaction to detect the presence of vegetative insecticidal protein gene (vip)-like sequences by using vip3aa1-specific primers. vip-like gene sequences were identified in eight serovars. these genes were cloned and sequenced. the deduced amino acid sequence of the vip3aa14 gene from bacillus thuringiensis tolworthi showed considerable differences as compared to those of vips reported so far. the vip3aa14 gene f ... | 2005 | 15686851 |
| insect-resistant transgenic pinus radiata. | transgenic radiata pine (pinus radiata d. don) plants containing a bacillus thuringiensis (bt) toxin gene, crylac, were produced by means of biolistic transformation of embryogenic tissue. using the selectable marker gene nptii and corresponding geneticin selection, 20 independent transgenic lines from five genotypes were established. over 200 plants regenerated from ten transgenic lines were successfully transferred to soil. the integration and expression of the introduced genes in transgenic t ... | 2005 | 15668791 |
| [construction of bacillus thuringiensis labeled recombinant strain and horizontal transfer of its cry1ac10 gene]. | a recombinant plasmid pbmbzgc10 was obtained by the ligation of gfp-cry1ac10 fusion gene and vector plasmid pad4412, which was then introduced by gene pulser into acrystalliferous strain cryb, and a recombinant strain cryb(pbmbzgc10) was obtained. different fermentative solutions of recombinant strain were used for multi-spraying on brassica pekinesis, ipomoea aquatica and lycopersicon esculentum leaves. the results of fluorescent detection and pcr amplification revealed that cry1ac10 gene did n ... | 2005 | 15852975 |
| insect-resistant gm rice in farmers' fields: assessing productivity and health effects in china. | although no country to date has released a major genetically modified (gm) food grain crop, china is on the threshold of commercializing gm rice. this paper studies two of the four gm varieties that are now in farm-level preproduction trials, the last step before commercialization. farm surveys of randomly selected farm households that are cultivating the insect-resistant gm rice varieties, without the aid of experimental station technicians, demonstrate that when compared with households cultiv ... | 2005 | 15860626 |
| impact of environmental factors on the toxicity of bacillus thuringiensis var. israelensis ips82 to chironomus kiiensis. | to determine the feasibility of microbiological control of chironomid larvae in water sources for the city of shenzhen, china, the toxicity characteristics of bacillus thuringiensis var. israelensis (bti) ips82 on chironomus kiiensis tokunaga were studied. tests on fermentation products of ips82 showed good correlations between toxicity, cell density, dissolved oxygen, and the spore-forming phase. in this study, bioassays were carried out with different stage larvae. results showed that the lc50 ... | 2005 | 15825763 |
| integration of bacillus thuringiensis h-14 formulations and pyriproxyfen for the control of larvae of aedes aegypti and aedes albopictus. | studies were carried out on the bioefficacy and residual activity of bacillus thuringiensis israelensis h-14 (bti) (water-dispersible granules of vectobac abg 6511 and liquid formulations of vectobac 12as) and pyriproxyfen (insect growth regulator, sumilarv 0.5%) as direct applications for control of larvae of aedes aegypti and aedes albopictus. two dosages of each bti formulation (285 and 570 international toxic units [itu]/liter) and the integration of both bti formulations and pyriproxyfen we ... | 2005 | 15825767 |
| [the chemotactic characteristics of the s and r dissociants of bacillus thuringiensis]. | the chemotactic responses of bacillus thuringiensis subsp. dendrolimus (strain 49) and thuringiensis (strain 2002) and their morphological dissociants were studied by using some natural and artificial substances as effectors. the 12-h-old wild-type cells (s variants) of both strains were found to be motile and similar in their chemotactic responses, whereas the chemotactic responses of r variants were different. | 2005 | 15835783 |
| transfer and expression of the mosquitocidal plasmid pbtoxis in bacillus cereus group strains. | the toxicity of bacillus thuringiensis subsp. israelensis to dipteran larvae (mosquitoes and black flies) depends on the presence of the pbtoxis plasmid. in this paper, two antibiotic resistance tagged pbtoxis were transferred by conjugation to other bacillus cereus group strains. among 15 potential recipients, only a lepidopteran active b. thuringiensis subspecies kurstaki and a b. cereus strain received the plasmid pbtoxis with a low transfer rate of about 10(-8) transconjugants/recipient. the ... | 2005 | 15837378 |
| plasmid-encoded regulator of extracellular proteases in bacillus anthracis. | bacillus anthracis sterne cured of the pxo1 plasmid had enhanced secreted protease activity during the postexponential phase but no change in hemolytic or lecithinase activities. a zymogen profile revealed at least six proteases, including serine, metal, and perhaps cysteine types. there were similar amounts of protease secreted by the closely related species bacillus cereus and bacillus thuringiensis, but the patterns differed. among the pxo1 plasmid-encoded proteins, there is a tetratricopepti ... | 2005 | 15838040 |
| comparison of broiler performance when fed diets containing corn grain with insect-protected (corn rootworm and european corn borer) and herbicide-tolerant (glyphosate) traits, control corn, or commercial reference corn. | a 42-d feeding experiment with growing ross x ross 508 broilers showed that the nutritional value of insect-protected and herbicide-tolerant corn was comparable to that of the genetically similar control and 5 commercial reference corn hybrids. mon 88017 provides protection from feeding damage by coleopteran pest corn rootworm and is tolerant to the action of glyphosate, the active ingredient in the roundup family of agricultural herbicides. mon 88017 x mon 810 was developed by the traditional b ... | 2005 | 15844815 |
| comparison of the localization of bacillus thuringiensis cry1a delta-endotoxins and their binding proteins in larval midgut of tobacco hornworm, manduca sexta. | tobacco hornworm, manduca sexta, is a model insect for studying the action of bacillus thuringiensis (bt) cry toxins on lepidopterans. the proteins, which bind bt toxins to midgut epithelial cells, are key factors involved in the insecticidal functions of the toxins. three cry1a-binding proteins, viz., aminopeptidase n (apn), the cadherin-like bt-r1, and membrane-type alkaline phosphatase (m-alp), were localized, by immunohistochemistry, in sections from the anterior, middle, and posterior regio ... | 2005 | 15902495 |
| field studies on the environmental fate of the cry1ab bt-toxin produced by transgenic maize (mon810) and its effect on bacterial communities in the maize rhizosphere. | field studies were done to assess how much of the transgenic, insecticidal protein, cry1ab, encoded by a truncated cry1ab gene from bacillus thuringiensis (bt), was released from bt-maize mon810 into soil and whether bacterial communities inhabiting the rhizosphere of mon810 maize were different from those of the rhizosphere of nontransgenic maize cultivars. bacterial community structure was investigated by sscp (single-strand conformation polymorphism) of pcr-amplified 16s rrna genes from commu ... | 2005 | 15969733 |
| the plasmid pbmbt1 from bacillus thuringiensis subsp. darmstadiensis (inta mo14-4) replicates by the rolling-circle mechanism and encodes a novel insecticidal crystal protein-like gene. | this work describes a novel rolling-circle replicating (rcr) plasmid pbmbt1 from bacillus thuringiensis subsp. darmstadiensis (inta mo14-4) encoding an insecticidal crystal protein-like gene. pbmbt1 (6700 bp) contains three orfs and their putative transcription initiation sites and shine-dalgarno sequences were localized. orf1 encodes a 34.6 kda protein which showed identity with the protein cryc53 from b. thuringiensis subsp. cameroun (24.6%), the cry15aa insecticidal crystal protein from b. th ... | 2005 | 15970328 |
| evaluation of transgenic cotton varieties and a glyphosate application on seedling disease incidence. | a study was conducted to determine whether stand densities of transgenic cotton (gossypium hirsutum) varieties, with or without glyphosate, were similar to conventional varieties of the same lineage group in georgia and mississippi. transgenic and conventional cotton varieties were placed into five lineage groups of related varieties and seedling disease was evaluated in three greenhouse tests and a field trial using rhizoctonia solani ag-4. seed vigor was determined by standard germination stud ... | 2005 | 15973787 |
| location of the bombyx mori aminopeptidase n type 1 binding site on bacillus thuringiensis cry1aa toxin. | we analyzed the binding site on cry1aa toxin for the cry1aa receptor in bombyx mori, 115-kda aminopeptidase n type 1 (bmapn1) (k. nakanishi, k. yaoi, y. nagino, h. hara, m. kitami, s. atsumi, n. miura, and r. sato, febs lett. 519:215-220, 2002), by using monoclonal antibodies (mabs) that block binding between the binding site and the receptor. first, we produced a series of mabs against cry1aa and obtained two mabs, mabs 2c2 and 1b10, that were capable of blocking the binding between cry1aa and ... | 2005 | 16000811 |
| bt toxin not guilty by association. | 2005 | 16003355 | |
| influence of bacillus thuringiensis var. israelensis on oviposition of aedes albopictus (skuse). | the effect of bacillus thuringiensis var israelensis (b.t.i.) on the oviposition behavior of aedes albopictus was evaluated in the field and laboratory in clemson, sc, u.s.a. in the field, water taken from containers in which mosquito larvae were reared (conditioned water) was placed in 16 containers. eight containers received 50 jld of b.t.i., and eight with water only were kept as controls. in the laboratory, field-collected females of ae. albopictus were placed in rearing chambers and provide ... | 2005 | 16007954 |
| toxicity and effects of microbial mosquito larvicides and larvicidal oil on the development and fecundity of the tadpole shrimp triops newberryi (packard) (notostraca: triopsidae). | tadpole shrimp (tps), triops newberryi (packard) (notostraca: triopsidae), is a predatory agent for immature mosquitoes breeding in aquatic habitats. this biological control agent could be used with other larvicides in mosquito control programs. in order to elucidate compatibility of the tps and commonly used mosquito larvicides, studies were initiated to investigate effects of bacillus thuringiensis ssp. israelensis (b.t.i.) de barjac, bacillus sphaericus neide and golden bear-1111 larvicidal o ... | 2005 | 16007963 |
| evaluation of various control agents against mosquito larvae in rice paddies in taiwan. | a field test was conducted in rice paddies adjacent to wufeng, taichung county in central taiwan to evaluate the efficacy of control agents against mosquito larvae. the agents included bacillus thuringienesis israelensis (bti), two lagenidium giganteum products (lg product a and t), and temephos. the major mosquito species found in the rice paddies were culex tritaeniorhynchus/vishnui and anopheles sinensis. compared to controls, a 7-day treatment with bti or lg products a and t caused overall r ... | 2005 | 16007966 |
| non-larvicidal effects of bacillus thuringiensis israelensis and bacillus sphaericus on oviposition and adult mortality of culex quinquefasciatus say (diptera: culicidae). | two microbial mosquito larvicides, bacillus thuringiensis ssp. israelensis (bti) and bacillus sphaericus (bsph), have been shown to be highly effective in controlling mosquito larvae and have been used in larvicidal programs for many years. in exploring other modes of action of these agents, we studied the ovipositional response of bsph susceptible and resistant culex quinquefasciatus to aqueous suspensions of bti and bsph water dispersible granules (wdg). we quantified the level of mortality of ... | 2005 | 16007971 |
| genes and environment interact to determine the fitness costs of resistance to bacillus thuringiensis. | genes which provide resistance to novel challenges such as pesticides, toxins or pathogens often impose fitness costs on individuals with a resistant phenotype. studies of resistance to bacillus thuringiensis and its insecticidal cry toxins indicate that fitness costs may be variable and cryptic. using two field populations (karak and serd4) of the diamondback moth, plutella xylostella, we tested the hypothesis that the costs associated with resistance to the b. thuringiensis toxin cry1ac would ... | 2005 | 16011928 |
| association analysis between serotype, cry gene content, and toxicity to helicoverpa armigera larvae among bacillus thuringiensis isolates native to spain. | serotyping, cry gene content, and toxicity to helicoverpa armigera were determined for 178 isolates of bacillus thuringiensis native to spain. a total of 13 different cry1 and cry2 genes were detected when isolates were screened by pcr analysis. results showed that cry2 and cry1ia were the most frequent cry genes in the collection (74 and 57%, respectively); whereas cry1d, cry1aa, cry1ab, and cry1c were only moderately abundant (49, 48, 47, and 36%, respectively). the most uncommon cry genes wer ... | 2005 | 16019024 |
| residual effect of two bacillus thuringiensis var. israelensis products assayed against aedes aegypti (diptera: culicidae) in laboratory and outdoors at rio de janeiro, brazil. | resistance of the dengue vector to temephos stimulated its substitution for bacillus thuringiensis var. israelensis (bti) since 2001 in brazil. the persistence of the two bti formulations employed at that time by the health ministry, vectobac g and aquabac g, was assayed under laboratory and outdoor conditions. both formulations were tested at 0.2 g/10 liters of water, the same concentration applied in the field for vector control. the tests were done against ae. aegypti third instar larvae (roc ... | 2005 | 16021284 |
| association between resistance to bt cotton and cadherin genotype in pink bollworm. | two strains of pink bollworm, pectinophora gossypiella (saunders), each derived in 1997 from a different field population, were selected for resistance to bacillus thuringiensis (bt) toxin cry1ac in the laboratory. one strain (mov97-r) originated from mohave valley in western arizona; the other strain (saf97-r) was from safford in eastern arizona. relative to a susceptible laboratory strain, cry1ac resistance ratios were 1700 for mov97-r and 520 for saf97-r. for the two resistant strains, larval ... | 2005 | 16022286 |
| suitability of commercially available insect traps and pheromones for monitoring dusky sap beetles (coleoptera: nitidulidae) and related insects in bt sweet corn. | two trap types and pheromone sources for the dusky sap beetle, carpophilus lugubris murray (coleoptera: nitidulidae), were compared in bacillus thuringiensis (bt) and non-bt sweet corn fields over a 3-yr period. overall, commercial traps and pheromones were equally effective as experimental traps and pheromones used previously for capturing c. lugubris and other sap beetle species. the commercial trap often caught significantly more glischrochilus quadrisignatus say than the experimental trap th ... | 2005 | 16022314 |
| effects of cotton cultivar on fitness costs associated with resistance of pink bollworm (lepidoptera: gelechiidae) to bt cotton. | fitness costs associated with insect resistance to transgenic crops producing toxins from bacillus thuringiensis (bt) reduce the fitness on non-bt refuge plants of resistant individuals relative to susceptible individuals. because costs may vary among host plants, choosing refuge cultivars that increase the dominance or magnitude of costs could help to delay resistance. specifically, cultivars with high concentrations of toxic phytochemicals could magnify costs. to test this hypothesis, we compa ... | 2005 | 16022327 |
| economic analysis of dynamic management strategies utilizing. transgenic corn for control of western corn rootworm (coleoptera: chrysomelidae). | we studied management strategies for western corn rootworm, diabrotica virgifera virgifera leconte, using transgenic corn, zea mays l., from both a biological and an economic perspective. in areas with and without populations adapted to a 2-yr rotation of corn and soybean (rotation-resistant), the standard management strategy was to plant 80% of a cornfield (rotated and continuous) to a transgenic cultivar each year. in each area, we also studied dynamic management strategies where the proportio ... | 2005 | 16022329 |
| season-long variation in expression of cry1ac gene and efficacy of bacillus thuringiensis toxin in transgenic cotton against helicoverpa armigera (lepidoptera: noctuidae). | the insertion of genes encoding insecticidal cry1a delta-endotoxins from the bacterium bacillus thuringiensis berliner variety kurstaki (bt) into varieties of cotton (gossypium spp.) was undertaken to assist in the control of a range of lepidopteran pests. in australia, where helicoverpa armigera (hübner) and helicoverpa punctigera (wallengren) are major pests, the level of control is useful, but not complete, because efficacy declines as the crop matures. fluctuations in the efficacy of bt cott ... | 2005 | 16022333 |
| effects of bt maize-fed prey on the generalist predator poecilus cupreus l. (coleoptera: carabidae). | we investigated the effects of transgenic maize (zea mays) expressing bacillus thuringienses toxin (bt maize) on larval and adult poecilus cupreus carabid beetles in laboratory studies. in no-choice trials, neonate p. cupreus larvae were fed exclusively with spodoptera littoralis caterpillars, which had been raised on bt maize. s. littoralis raised on conventional maize or "high quality" calliphora sp. pupae were fed to the beetle larvae in two control treatments. bt-maize-fed caterpillar prey i ... | 2005 | 16022384 |
| effects of bt maize on the herbivore spodoptera littoralis (lepidoptera: noctuidae) and the parasitoid cotesia marginiventris (hymenoptera: braconidae). | recent studies have shown that transgenic insect resistant plants can have negative effects on non-target herbivores as well as on beneficial insects. the study of tritrophic interactions gives insight into the complex mechanisms of food webs in the field and can easily be incorporated into a tiered risk assessment framework. we investigated the effects of transgenic maize (zea mays) expressing insecticidal proteins derived from bacillus thuringiensis (bt maize) on spodoptera littoralis, a non-t ... | 2005 | 16022385 |
| the cost of resistance to bacillus thuringiensis varies with the host plant of trichoplusia ni. | selection for resistance to insecticides, diseases and parasitoids is assumed to be costly and often requires tradeoffs with reproductive fitness. the costs of resistance, however, are often difficult to measure. cabbage looper, trichoplusia ni, a generalist lepidopteran herbivore, has become highly resistant following the extensive use of the microbial insecticide, bacillus thuringiensis kurstaki (bt) in vegetable greenhouses. we compared the growth rate, pupal size and survival of resistant, s ... | 2005 | 16024361 |
| detection of genetically modified corn (bt176) in spiked cow blood samples by polymerase chain reaction and immunoassay methods. | the fate of dna and protein transgenic sequences in products derived from animals fed transgenic crops has recently raised public interest. sensitive molecular tests targeting the bt176 genetic construct and the transgenic cry1ab protein were developed to determine whether plant sequences, especially transgenic sequences, are present in animal products. a protocol for total dna extraction and purification from cow whole blood samples was first drawn up and assessed by spiking with known amounts ... | 2005 | 15861534 |
| the linear double-stranded dna of phage bam35 enters lysogenic host cells, but the late phage functions are suppressed. | bam35, a temperate double-stranded dna bacteriophage with a 15-kb linear genome, infects gram-positive bacillus thuringiensis cells. bam35 morphology and genome organization resemble those of prd1, a lytic phage infecting gram-negative bacteria. bam35 and prd1 have an outer protein coat surrounding a membrane that encloses the viral dna. we used electrochemical methods to investigate physiological changes of the lysogenic and nonlysogenic hosts during bam35 dna entry and host cell lysis. during ... | 2005 | 15866940 |
| new resistance mechanism in helicoverpa armigera threatens transgenic crops expressing bacillus thuringiensis cry1ac toxin. | in australia, the cotton bollworm, helicoverpa armigera, has a long history of resistance to conventional insecticides. transgenic cotton (expressing the bacillus thuringiensis toxin cry1ac) has been grown for h. armigera control since 1996. it is demonstrated here that a population of australian h. armigera has developed resistance to cry1ac toxin (275-fold). some 70% of resistant h. armigera larvae were able to survive on cry1ac transgenic cotton (ingard) the resistance phenotype is inherited ... | 2005 | 15870346 |
| tolerance of bt corn (mon 810) to maize stem borer, chilo partellus (lepidoptera: pyralidae). | transgenic corn (mon 810), expressing the bacillus thuringiensis (bt) protein, cry1ab, was evaluated under greenhouse conditions for its tolerance to the maize stem borer, chilo partellus. bt corn (mon 810) provided effective protection against the stem borer even under a high level of larval infestation in the greenhouse. the observed tolerance is examined and discussed in the light of the susceptibility of c. partellus to the cry1ab protein in laboratory bioassays. the implications of the tiss ... | 2005 | 15875192 |
| discovery and utilization of qtls for insect resistance in soybean. | insect resistance in soybean has been an objective in numerous breeding programs, but efforts to develop high yielding cultivars with insect resistance have been unsuccessful. three japanese plant introductions, pis 171451, 227687 and 229358, have been the primary sources of insect resistance alleles, but a combination of quantitative inheritance of resistance and poor agronomic performance has hindered progress. linkage drag caused by co-introgression of undesirable agronomic trait alleles link ... | 2005 | 15881690 |
| assessment of cone-damaging insects in a swedish spruce seed orchard and the efficacy of large-scale application of bacillus thuringiensis variety aizawai x kurstaki against lepidopterans. | in a 2-yr study, we investigated the efficacy of large-scale application of the biological insecticide bacillus thuringiensis variety aizawai x kurstaki (btk) in a swedish spruce, picea abies l. (karst.), seed orchard for controlling damage caused by four lepidopteran species: dioryctria abietella den et. schiff. (pyralidae), eupithecia abietaria götze, e. analoga djakonov (geometridae), and cydia strobilella (l.) (tortricidae). the frequencies of these species, and strobilomyia anthracina czern ... | 2005 | 15889731 |
| hymenopteran parasitoids of diamondback moth (lepidoptera: ypeunomutidae) in northern thailand. | larvae of the diamondback moth, plutella xylostella (l.) (lepidoptera: ypeunomutidae), cause severe economic damage to cabbage, brassica oleracea l. variety capitata (brassicaceae) and related vegetables in thailand. overuse of broad-spectrum insecticides for diamondback moth control is a serious problem and has obscured the contributions of indigenous parasitoids. our objectives were to identify indigenous diamondback moth parasitoids in northern thailand and to assess their potential for natur ... | 2005 | 15889737 |
| effects of sublethal concentrations of bacillus thuringiensis on larval development of sesamia nonagrioides. | in the mediterranean basin, developed diapausing larvae of the borer sesamia nonagrioides lefèbvre are found consistently during autumn in transgenic corn, zea mays l., expressing bacillus thuringiensis berliner (bt) toxins derived from event 176. these larvae can feed on sublethal concentrations of bt toxins because the expression of this corn toxin declines after flowering. to evaluate the possible consequences of this phenomenon, the effect of sublethal concentrations of the natural toxin pro ... | 2005 | 15889739 |
| laboratory and field evaluations of transgenic soybean exhibiting high-dose expression of a synthetic bacillus thuringiensis cry1a gene for control of lepidoptera. | transgenic lines of soybean, glycine max (l.) merrill, expressing a synthetic cry1a gene (tic107) from bacillus thuringiensis (bt), were evaluated in screenhouse and conventional field trials for efficacy against lepidopteran pests. in screenhouse trials, bt soybean and negative checks (isogenic segregants and parental lines) were evaluated against anticarsia gemmatalis hübner and pseudoplusia includens (walker) in the united states and against a. gemmatalis, epinotia aporema (walsingham), rachi ... | 2005 | 15889751 |
| comprehensive assignment of mass spectral signatures from individual bacillus atrophaeus spores in matrix-free laser desorption/ionization bioaerosol mass spectrometry. | we have fully characterized the mass spectral signatures of individual bacillus atrophaeus spores obtained using matrix-free laser desorption/ionization bioaerosol mass spectrometry (bams). mass spectra of spores grown in unlabeled, 13c-labeled, and 15n-labeled growth media were used to determine the number of carbon and nitrogen atoms associated with each mass peak observed in mass spectra from positive and negative ions. to determine the parent ion structure associated with fragment ion peaks, ... | 2005 | 15889924 |
| many roads to resistance: how invertebrates adapt to bt toxins. | the cry family of bacillus thuringiensis insecticidal and nematicidal proteins constitutes a valuable source of environmentally benign compounds for the control of insect pests and disease agents. an understanding of cry toxin resistance at a molecular level will be critical to the long-term utility of this technology; it may also shed light on basic mechanisms used by other bacterial toxins that target specific organisms or cell types. selection and cross-resistance studies have confirmed that ... | 2005 | 15892110 |
| the synergistic activity between cry1aa and cry1c from bacillus thuringiensis against spodoptera exigua and helicoverpa armigera. | to investigate the interaction between two crystal proteins, cry1aa and cry1c, for future development of biopesticides based on bacillus thuringiensis, toxicities of the two individual proteins and in combinations have been determined against spodoptera exigua and helicoverpa armigera larvae, and synergism between the proteins has been evaluated using synergistic factor. | 2005 | 15892743 |
| is the mature endotoxin cry1ac from bacillus thuringiensis inactivated by a coagulation reaction in the gut lumen of resistant helicoverpa armigera larvae? | bacillus thuringiensis endotoxins (bt-toxins) are the most important biopesticides used in controlling insect pests and vectors of diseases. the emergence of widespread resistance to bt in some insect species is a serious threat to agricultural production. analysis of bt-resistant and susceptible laboratory strains of helicoverpa armigera revealed elevated immune responses involving increased melanization and the presence of a soluble toxin-binding glycoprotein in the hemolymph and gut lumen of ... | 2005 | 15894190 |
| crystallization and preliminary crystallographic analysis of bacillus thuringiensis ahl-lactonase. | the quorum sensing (qs) systems in gram-negative bacteria are mostly associated with diffusible n-acyl-l-homoserine lactones (ahls). ahl-degrading enzymes hydrolyze the ahls into inactive molecules, thereby blocking the qs systems that are closely linked to virulence factor production and biofilm formation. consequently, these enzymes have recently attracted intense interest for the development of anti-infection therapies for plants and animals. however, despite significant progress in the inves ... | 2005 | 15894524 |
| the quorum-quenching lactonase from bacillus thuringiensis is a metalloprotein. | lactonases from bacillus species hydrolyze the n-acylhomoserine lactone (ahl) signaling molecules used in quorum-sensing pathways of many gram-negative bacteria, including pseudomonas aeruginosa and erwinia carotovora, both significant pathogens. because of sequence similarity, these ahl lactonases have been assigned to the metallo-beta-lactamase superfamily of proteins, which includes metalloenzymes of diverse activity, mechanism, and metal content. however, a recent study claims that ahl lacto ... | 2005 | 15895999 |
| toxicity of several delta-endotoxins of bacillus thuringiensis against helicoverpa armigera (lepidoptera: noctuidae) from spain. | toxicity and larval growth inhibition of 11 insecticidal proteins of bacillus thuringiensis were evaluated against neonate larvae of helicoverpa armigera, a major pest of important crops in spain and other countries, by a whole-diet contamination method. the most active toxins were cry1ac4 and cry2aa1, with lc50 values of 3.5 and 6.3 microg/ml, respectively. at the concentrations tested, cry1ac4, cry2aa1, cry9ca, cry1fa1, cry1ab3, cry2ab2, cry1da, and cry1ja1, produced a significant growth inhib ... | 2005 | 15913643 |
| cytotoxicity of bacillus thuringiensis cry1ab toxin depends on specific binding of the toxin to the cadherin receptor bt-r1 expressed in insect cells. | the specific role of cadherin receptors in cytotoxicity involving cry toxins of bacillus thuringiensis and their interactions with cell membrane has not been defined. to elucidate the involvement of toxin-membrane and toxin-receptor interactions in cytotoxicity, we established a cell-based system utilizing high five insect cells stably expressing bt-r1, the cadherin receptor for cry1ab toxin. cry1ab toxin is incorporated into cell membrane in both oligomeric and monomeric form. monomeric toxin b ... | 2005 | 15920532 |
| a simple purification and activity assay of the coagulant protein from moringa oleifera seed. | use of extracts from moringa oleifera (mo) is of great interest for low-cost water treatment. this paper discusses water and salt extraction of a coagulant protein from the seed, purification using ion exchange, its chemical characteristics, coagulation and antimicrobial properties. the coagulant from both extracts is a cationic protein with pi greater than 9.6 and molecular mass less than 6.5 kda. mass spectrometric analysis of the purified water extract indicated that it contained at least fou ... | 2005 | 15921719 |
| regulating insect resistance management: the case of non-bt corn refuges in the us. | in this paper, we analyze the insect resistance management (irm) plan put in place by the us environmental protection agency (epa) to delay the evolution of resistance to bt corn in natural populations of the european corn borer, ostrinia nubilalis hübner. this irm plan is the most impressive mandatory irm system ever developed. it forms a coherent whole and includes mandatory refuges, actions to increase growers' compliance and a program for monitoring the evolution of resistance. however, our ... | 2005 | 15922504 |
| evolutionary trade-offs of insect resistance to bacillus thuringiensis crops: fitness cost affecting paternity. | evolution of resistance to insecticides provides a useful model for examining fitness trade-offs associated with adaptation to stress. here, we examined male reproductive costs in pink bollworm (pectinophora gossypiella) resistant to an insecticidal protein of bacillus thuringiensis (bt) produced by transgenic cotton, using contrasts between two pairs of related susceptible and resistant strains. without competition for access to females, no costs affecting reproductive success of resistant male ... | 2005 | 15926701 |
| novel genetic basis of field-evolved resistance to bt toxins in plutella xylostella. | insecticidal toxins from bacillus thuringiensis (bt) are widely used to control pest insects, but evolution of resistance threatens their continued efficacy. the most common type of bt resistance ('mode 1') is characterized by recessive inheritance, > 500-fold resistance to at least one cry1a toxin, negligible cross-resistance to cry1c, and reduced binding of bt toxins to midgut membrane target sites. mutations affecting a cry1a-binding midgut cadherin protein are linked to laboratory-selected m ... | 2005 | 15926902 |
| identification of a promoter for the vegetative insecticidal protein-encoding gene vip3lb from bacillus thuringiensis. | the expression of vip3lb, one of the vegetative insecticidal protein-encoding genes of bacillus thuringiensis, was studied at the transcriptional level. by primer extension analysis, we have identified, for the first time, the transcription start point of vip3-type gene. upstream from vip3lb transcription start point, was found a nucleotide sequence partially homologous to the consensus sequence for the e sigma(e) holoenzyme of b. subtilis. thus, it was strongly suggested that the identified vip ... | 2005 | 15927753 |
| dielectric monitoring of growth and sporulation of bacillus thuringiensis. | on-line permittivity and optical density measurements have been used to monitor biomass concentration and sporulation status during growth of a spore-forming bacterium, bacillus thuringiensis, in fed-batch culture. the correlation between permittivity, optical density and other observations showed three distinct phases of growth: growth itself, transition and sporulation. the permittivity variations during the transition and sporulation phases could be related to the sporulation development: the ... | 2005 | 15928859 |
| cloning and expression of mel gene from bacillus thuringiensis in escherichia coli. | previous work from our laboratory has shown that most of bacillus thuringiensis strains possess the ability to produce melanin in the presence of l -tyrosine at elevated temperatures (42 degrees c). furthermore, it was shown that the melanin produced by b. thuringiensis was synthesized by the action of tyrosinase, which catalyzed the conversion of l -tyrosine, via l -dopa, to melanin. in this study, the tyrosinase-encoding gene (mel) from b. thuringiensis 4d11 was cloned using pcr techniques and ... | 2005 | 15928981 |
| surface display of recombinant proteins on bacillus thuringiensis spores. | the insecticidal protoxin from bacillus thuringiensis has been shown to be a major component of the spore coat. we have developed a novel surface display system using b. thuringiensis spores in which the n-terminal portion of the protoxin is replaced with a heterologous protein. the expression vector with a sporulation-specific promoter was successfully used to display green fluorescent protein and a single-chain antibody (scfv) gene that encodes anti-4-ethoxymethylene-2-phenyl-2-oxazolin-5-one ... | 2005 | 15933037 |
| concurrent use of transgenic plants expressing a single and two bacillus thuringiensis genes speeds insect adaptation to pyramided plants. | transgenic plants expressing insecticidal proteins from the bacterium bacillus thuringiensis (bt) were grown on over 13 million ha in the united states and 22.4 million ha worldwide in 2004. preventing or slowing the evolution of resistance by insects ("resistance management") is critical for the sustainable use of bt crops. plants containing two dissimilar bt toxin genes in the same plant ("pyramided") have the potential to delay insect resistance. however, the advantage of pyramided bt plants ... | 2005 | 15939892 |
| environmental fate and effects of bacillus thuringiensis (bt) proteins from transgenic crops: a review. | this paper reviews the scientific literature addressing the environmental fate and nontarget effects of the cry protein toxins from bacillus thuringiensis (bt), specifically resulting from their expression in transgenic crops. published literature on analytical methodologies for the detection and quantification of the cry proteins in environmental matrices is also reviewed, with discussion of the adequacy of the techniques for determining the persistence and mobility of the bt proteins. in gener ... | 2005 | 15941295 |
| identification of cry-type genes on 20-kb dna associated with cry1 crystal proteins from bacillus thuringiensis. | heterologous dna fragments (20-kb) associated with cry1 crystal proteins (protoxins) from a soil-isolated bacillus thuringiensis strain 4.0718 were isolated and analyzed. rflp patterns of the pcr products showed that the 20-kb dna fragments harbored cry1aa, cry1ac, cry2aa, and cry2ab genes. furthermore, a 4.2-kb dna fragment, which contained the promoter, the coding region, and the terminator of cry1ac gene, was cloned from the 20-kb dnas by pcr, and then the cry1ac gene was expressed in an acry ... | 2005 | 15942699 |
| characterization of cdnas encoding three trypsin-like proteinases and mrna quantitative analysis in bt-resistant and -susceptible strains of ostrinia nubilalis. | our previous studies suggested that bacillus thuringiensis (bt) resistance in a dipel-resistant strain of ostrinia nubilalis was primarily due to reduced trypsin-like proteinase activity. in this study, we demonstrated a 254-fold resistance to cry1ab protoxin but only 12-fold to trypsin-activated cry1ab toxin in the dipel-resistant strain. significantly higher resistance to cry1ab protoxin than to trypsin-activated cry1ab toxin further supports the hypothesis that reduced trypsin-like proteinase ... | 2005 | 15944081 |
| phosphatidylinositol-specific phospholipase c of bacillus anthracis down-modulates the immune response. | phosphatidylinositol-specific phospholipases (pi-plcs) are virulence factors produced by many pathogenic bacteria, including bacillus anthracis and listeria monocytogenes. bacillus pi-plc differs from listeria pi-plc in that it has strong activity for cleaving gpi-anchored proteins. treatment of murine dcs with bacillus, but not listeria, pi-plc inhibited dendritic cell (dc) activation by tlr ligands. infection of mice with listeria expressing b. anthracis pi-plc resulted in a reduced ag-specifi ... | 2005 | 15944308 |
| expanding the bactericidal action of the food color additive phloxine b to gram-negative bacteria. | phloxine b (d&c red no. 28) is a color additive for food, drugs, and cosmetics. it has been previously shown to have anti-staphylococcus aureus activities. in this work, the effect of phloxine b on various gram-negative bacteria and other gram-positive bacteria including bacillus cereus, bacillus thuringiensis, bacillus mycoides, bacillus subtilis, bacillus aureus, salmonella, escherichia coli and shigella was studied, along with the mechanism of anti-microbial activity. in the presence of fluor ... | 2005 | 15949926 |
| construction of a pseudomonas sp. derivative carrying the cry9aa gene from bacillus thuringiensis and a proposal for new standard criteria to assess entomocidal properties of bacteria. | an isolate of pseudomonas sp. (16s rdna sequence 98% homologous to p. graminis and p. lutea) was isolated from the phyllosphere of black pine in northern italy and used as a host for the gene encoding the cry9aa entomocidal toxin from bacillus thuringiensis subsp. galleriae. an expression system featuring a synthetic highest-consensus promoter specifically tailored for the regulated induction of cloned genes over a broad range of gram-negative bacteria was used to drive the production of the int ... | 2005 | 15950125 |
| a cryptic bacillus isolate exhibited narrow 16s rrna gene sequence divergence with bacillus thuringiensis and showed low maintenance requirements in hyper-osmotic complex substrate cultivations. | a cryptic bacillus (k90) isolate obtained from soil samples from the kuwait desert exhibited lower maintenance requirements in complex substrate cultivations than bacillus thuringiensis. a mathematical model was used to estimate apparent maintenance coefficients (m(c)) and these were found to be 0.336 and 0.041/h for b. thuringiensis and k90, respectively. the results also showed that the values of apparent maintenance coefficients were inversely related to the specific growth rates. furthermore ... | 2005 | 15959906 |
| laboratory studies of the effects of reduced prey choice caused by bt plants on a predatory insect. | crops transformed to express bacillus thuringiensis (bt) toxins can cause close to 100% mortality of certain target pest species. this study assessed the effect of target pest reduction on the predatory insect chrysoperla carnea (stephens) in the presence of alternative prey. numbers of lacewings recovered from bt oilseed rape (cultivar oscar, event o52) did not differ significantly from numbers of lacewings recovered from conventional oilseed rape in cage experiments with the target pest plutel ... | 2005 | 15960878 |
| synthesis of additional endotoxins in bacillus thuringiensis subsp. morrisoni pg-14 and bacillus thuringiensis subsp. jegathesan significantly improves their mosquitocidal efficacy. | a fundamental principal of resistance management is that the more complex and potent a toxin mixture, the slower resistance will develop to the mixture in an insect population. thus, to develop more complex and potent mosquitocidal bacteria, we genetically engineered bacillus thuringiensis subsp. morrisoni pg-14 and bacillus thuringiensis subsp. jegathesan, to synthesize, respectively, the binary (bin) toxin of bacillus sphaericus or a combination of bin and the cytla protein of bacillus thuring ... | 2005 | 15962784 |
| cry11aa toxin from bacillus thuringiensis binds its receptor in aedes aegypti mosquito larvae through loop alpha-8 of domain ii. | bacillus thuringiensis subs israelensis produces cry toxins active against mosquitoes. receptor binding is a key determinant for specificity of cry toxins composed of three domains. we found that exposed loop alpha-8 of cry11aa toxin, located in domain ii, is an important epitope involved in receptor interaction. synthetic peptides corresponding to exposed regions in domain ii (loop alpha-8, beta-4 and loop 3) competed binding of cry11aa to membrane vesicles from aedes aegypti midgut microvilli. ... | 2005 | 15963509 |
| toxicity of bacillus thuringiensis to parasitic and free-living life-stages of nematode parasites of livestock. | a collection of bacillus thuringiensis (bt) strains (bts) were screened for activity against the free-living larval stages of nematode parasites of livestock. two strains were identified with significant activity in inhibiting larval development of haemonchus contortus, trichostrongylus colubriformis and ostertagia circumcincta. these strains were also toxic to the adult parasitic stages of these nematode species in vitro. adult h. contortus and o. circumcincta showed complete cessation of movem ... | 2005 | 15964574 |
| recombinant larvicidal bacteria with markedly improved efficacy against culex vectors of west nile virus. | an urgent need exists for new agents to control mosquito vectors of disease. mosquito larvicides based on the bacteria bacillus thuringiensis subsp. israelensis (bti) or b. sphaericus (bs) are effective in many habitats, but use is limited by their high cost. moreover, mosquito resistance evolves rapidly to bs where it is used intensively. the efficacy of these bacteria is due to a binary protein (bsb) in bs and four proteins (cry4a, cry4b, cry11a, and cyt1a) in bti. here we report the use of cy ... | 2005 | 15964958 |
| using worms to better understand how bacillus thuringiensis kills insects. | bacillus thuringiensis is widely used as a biological pesticide to control insects that either cause damage to crops or transmit disease. that it can also target the model organism caenorhabditis elegans has not only provided exciting new insights into how the toxins produced by the bacterium target their victims but also how target insects counter the attack. modern approaches such as reverse genetics and microarray technology have revealed novel receptors for the toxins and possible signal tra ... | 2005 | 15967665 |
| [control of culicides by using bacillus thuringiensis sh-14 var. israelensis in permanent breeding places of fomento, province of sancti spiritus, cuba]. | an ecological evaluation of retrospective and descriptive temporary trend was conducted from 1999 to 2000 .in 8 water bodies of fomento, province of sancti spiritus. to evaluate the effectiveness and permanence of the biolarvicide, there were used data of systematic samplings and of control actions of the provincial surveillance and antivectorial fight programs taken from the records of each breeding place in the municipal unit of higiene and epidemiology of the locality. doses of 10 ml of activ ... | 2005 | 17969274 |
| interactions with microbial pathogens. | a wide variety of bacterial pathogens, as well as several fungi, kill c. elegans or produce non-lethal disease symptoms. this allows the nematode to be used as a simple, tractable model host for infectious disease. human pathogens that affect c. elegans include gram-negative bacteria of genera burkholderia, pseudomonas, salmonella, serratia and yersinia; gram-positive bacteria enterococcus, staphylococcus and streptococcus; and the fungus cryptococcus neoformans. microbes that are not pathogenic ... | 2005 | 18050390 |
| laboratory evaluation of bacillus thuringiensis h-14 against aedes aegypti. | laboratory efficacy and residual activity of a water dispersible granule formulation of bacillus thuringiensis israelensis (bti) at the dosages of 3000, 6000 and 15000 itu/l were conducted in this study. the study was conducted in two different size containers, earthen jar (45 l) and glass jar (3 l) with or without daily replenishment of 6 l and 0.3 l of water in the earthen and glass jars, respectively. results indicate that for both earthen jar and glass jar evaluations, bti at the tested dosa ... | 2005 | 16880748 |
| efficient growth inhibition of bacillus anthracis by knocking out the ribonucleotide reductase tyrosyl radical. | bacillus anthracis, the causative agent of anthrax, is a worldwide problem because of the need for effective treatment of respiratory infections shortly after exposure. one potential key enzyme of b. anthracis to be targeted by antiproliferative drugs is ribonucleotide reductase. it provides deoxyribonucleotides for dna synthesis needed for spore germination and growth of the pathogen. we have cloned, purified, and characterized the tyrosyl radical-carrying nrdf component of b. anthracis class i ... | 2005 | 16322104 |
| low persistence of bacillus thuringiensis serovar israelensis spores in four mosquito biotopes of a salt marsh in southern france. | we studied the persistence of bacillus thuringiensis serovar israelensis (bti) in a typical breeding site of the mosquito ochlerotatus caspius in a particularly sensitive salt marsh ecosystem following two bti-based larvicidal applications (vectobac 12as, 1.95 l/ha). the treated area was composed of four larval biotopes that differed in terms of the most representative plant species (sarcocornia fruticosa, bolboschoenus maritimus, phragmites australis, and juncus maritimus) and the physical and ... | 2005 | 16328650 |
| spatial variation in bacillus thuringiensis/cereus populations within the phyllosphere of broad-leaved dock (rumex obtusifolius) and surrounding habitats. | the aim of this study was to determine the prevalence and toxin gene diversity of bacillus thuringiensis/b. cereus in the phyllosphere of broad-leaved dock (rumex obtusifolius) at a small spatial scale. b. thuringiensis/cereus populations were isolated from the phyllosphere of dock and neighbouring grass and in neighbouring soil using commercially available selective media which avoided the disadvantageous heat-shock selection procedure. the maximum density of b. thuringiensis/cereus in the dock ... | 2005 | 16332339 |
| distribution of genes encoding putative virulence factors and fragment length polymorphisms in the vrra gene among brazilian isolates of bacillus cereus and bacillus thuringiensis. | one hundred twenty-one strains of the bacillus cereus complex, of which 80 were isolated from a variety of sources in brazil, were screened by pcr for the presence of sequences (bcet, hbla, nhebc, plc, sph, and vip3a) encoding putative virulence factors and for polymorphisms in variable-number tandem repeats (vntr), using a variable region of the vrra open reading frame as the target. amplicons were generated from isolates of b. cereus and bacillus thuringiensis for each of the sequences encodin ... | 2005 | 16332792 |
| flha influences bacillus thuringiensis plcr-regulated gene transcription, protein production, and virulence. | bacillus thuringiensis and bacillus cereus are closely related. b. thuringiensis is well known for its entomopathogenic properties, principally due to the synthesis of plasmid-encoded crystal toxins. b. cereus appears to be an emerging opportunistic human pathogen. b. thuringiensis and b. cereus produce many putative virulence factors which are positively controlled by the pleiotropic transcriptional regulator plcr. the inactivation of plcr decreases but does not abolish virulence, indicating th ... | 2005 | 16332888 |
| rapid ped-2e9 cell-based cytotoxicity analysis and genotyping of bacillus species. | bacillus species causing food-borne disease produce multiple toxins eliciting gastroenteritis. toxin assays with mammalian cell cultures are reliable but may take 24 to 72 h to complete and also lack sensitivity. here, a sensitive and rapid assay was developed using a murine hybridoma ped-2e9 cell model. bacillus culture supernatants containing toxins were added to a ped-2e9 cell line and analyzed for cytotoxicity with an alkaline phosphatase release assay. most bacillus cereus strains produced ... | 2005 | 16333068 |
| bollworm resistance to bt cotton in india. | 2005 | 16333282 | |
| cloning and characterization of a novel gene cry9ec1 encoding lepidopteran-specific parasporal inclusion protein from a bacillus thuringiensis serovar galleriae strain. | a novel delta-endotoxin gene from a lepidopteran-specific bacillus thuringiensis serovar galleriae strain was cloned, and the full sequence of the cry gene was determined. the cloned 6.5-kb dna fragment included the full sequence of the cry gene and three open reading frames located upstream of the cry gene. the gene, designated cry9ec1, encodes a polypeptide of 1154 amino acid residues with a predicted molecular weight of 130 237. the deduced amino acid sequence of the cry9ec1 protein had the h ... | 2005 | 16333339 |
| development of a bacillus thuringiensis-based assay on lygus hesperus. | lygus hesperus knight (hemiptera: miridae) is an economically important insect pest controlled primarily by chemical pesticides. bacillus thuringiensis berliner is a gram-positive bacterium, which upon sporulation produces a parasporal inclusion body, the crystal. the latter, in some strains, exhibits specific insecticidal activities against lepidopteran, coleopteran, or dipteran pests. the aim of the present work was to develop a bacillus thuringiensis-based assay on l. hesperus. several factor ... | 2005 | 16334312 |
| spray-dried bacillus thuringiensis serovar israelensis formulations for control of aedes aegypti larvae. | suspensions containing 0.25 and 1.25 g/liter of bacillus thuringiensis subsp. israelensis (bti) spore-toxin complex were spray-dried by using maltodextrin de-6, corn starch, and nixtamalized corn flour (25 g/liter) as materials to entrap active delta-endotoxin. the inlet air temperature of the drier was kept constant at 141 degrees c and the outlet temperature was maintained at 60 or 70 degrees c. the probit analysis of the concentration-mortality response of third instars of aedes aegypti (l.) ... | 2005 | 16334315 |