Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| virulent spores of bacillus anthracis and other bacillus species deposited on solid surfaces have similar sensitivity to chemical decontaminants. | to compare the relative sensitivity of bacillus anthracis and spores of other bacillus spp. deposited on different solid surfaces to inactivation by liquid chemical disinfecting agents. | 2007 | 17184315 |
| diversity of colombian strains of bacillus thuringiensis with insecticidal activity against dipteran and lepidopteran insects. | to evaluate the genetic and molecular diversity and insecticidal activity of bacillus thuringiensis isolates from all the natural regions of colombia. | 2007 | 17184322 |
| bacillus thuringiensis fermentation of hydrolyzed sludge--rheology and formulation studies. | rheology of bacillus thuringiensis fermentation of hydrolyzed sludge was investigated in bench scale fermenter. stable liquid formulations were developed and optimized for two-year based studies comprising various physical/chemical (viscosity, particle size, corrosion and suspendibility) and biological (microbial contamination, viable spores and entomotoxicity) parameters at different phs and temperatures. the hydrolyzed sludge depicted non-newtonian and pseudoplastic behaviour during fermentati ... | 2007 | 17184817 |
| mechanism of resistance to bacillus thuringiensis toxin cry1ac in a greenhouse population of the cabbage looper, trichoplusia ni. | the cabbage looper, trichoplusia ni, is one of only two insect species that have evolved resistance to bacillus thuringiensis in agricultural situations. the trait of resistance to b. thuringiensis toxin cry1ac from a greenhouse-evolved resistant population of t. ni was introgressed into a highly inbred susceptible laboratory strain. the resulting introgression strain, glen-cry1ac-bcs, and its nearly isogenic susceptible strain were subjected to comparative genetic and biochemical studies to det ... | 2007 | 17189446 |
| mode of action of bacillus thuringiensis cry and cyt toxins and their potential for insect control. | bacillus thuringiensis crystal (cry) and cytolitic (cyt) protein families are a diverse group of proteins with activity against insects of different orders--lepidoptera, coleoptera, diptera and also against other invertebrates such as nematodes. their primary action is to lyse midgut epithelial cells by inserting into the target membrane and forming pores. among this group of proteins, members of the 3-domain cry family are used worldwide for insect control, and their mode of action has been cha ... | 2007 | 17198720 |
| parasporin-1, a novel cytotoxic protein from bacillus thuringiensis, induces ca2+ influx and a sustained elevation of the cytoplasmic ca2+ concentration in toxin-sensitive cells. | parasporin-1 is a novel non-insecticidal inclusion protein from bacillus thuringiensis that is cytotoxic to specific mammalian cells. in this study, we investigated the effects of parasporin-1 on toxin-sensitive cell lines to elucidate the cytotoxic mechanism of parasporin-1. parasporin-1 is not a membrane pore-forming toxin as evidenced by measurements of lactate dehydrogenase release, propidium iodide penetration, and membrane potential in parasporin-1-treated cells. parasporin-1 decreased the ... | 2007 | 17204466 |
| genetic transformation of chickpea (cicer arietinum l.) with insecticidal crystal protein gene using particle gun bombardment. | here, we report the establishment of an efficient particle gun bombardment mediated genetic transformation in chickpea (cicer arietinum l.) using cryiac gene of bacillus thuringiensis. explants were bombarded with recombinant plasmids engineered for the expression of cryiac transgene in plants and stable transformants regenerated in presence of benzyladenine, kinetin and kanamycin. transformation frequency showed dependence on explant type, cultivars, plasmids, helium pressure and microcarrier t ... | 2007 | 17205334 |
| permeability changes of manduca sexta midgut brush border membranes induced by oligomeric structures of different cry toxins. | the pore-formation activity of monomeric and oligomeric forms of different cry1 toxins (from cry1a to cry1g) was analyzed by monitoring ionic permeability across manduca sexta brush border membrane vesicles. the membrane vesicles were isolated from microvilli structures, showing a high enrichment of apical membrane markers and low intrinsic k(+) permeability. a fluorometric assay performed with 3,3'-dipropylthiodicarbocyanine fluorescent probe, sensitive to changes in membrane potential, was use ... | 2007 | 17206518 |
| varietal effects of eight paired lines of transgenic bt maize and near-isogenic non-bt maize on soil microbial and nematode community structure. | a glasshouse experiment was undertaken to provide baseline data on the variation between conventional maize (zea mays l.) varieties and genetically modified maize plants expressing the insecticidal bacillus thuringiensis protein (bt, cry1ab). the objective was to determine whether the variation in soil parameters under a range of conventional maize cultivars exceeded the differences between bt and non-bt maize cultivars. variations in plant growth parameters (shoot and root biomass, percentage c ... | 2007 | 17207257 |
| btm-p1 polycationic peptide biological activity and 3d-dimensional structure. | the novel btm-p1 peptide interferes with energetic processes in mitochondria; its antimicrobial activity against gram-positive and gram-negative bacteria is described here. btm-p1 three-dimensional structure was determined by 1h nmr to explain its biological mechanisms and membrane activity. structural data indicated that btm-p1 can form an alpha-helix; circular dichroism analysis confirmed the peptide's propensity to behave as a typical transmembrane helix in a lipidic environment. according to ... | 2007 | 17207468 |
| insecticidal toxins from photorhabdus bacteria and their potential use in agriculture. | most of the insecticidal toxins used in agriculture come from a single bacterium bacillus thuringiensis or 'bt'. here we review our work on the array of toxins produced by photorhabdus and xenorhabdus bacteria that are symbiotic with entomopathogenic nematodes, and discuss their potential for use in agriculture as alternatives to bt. despite the fact that both photorhabdus and xenorhabdus are introduced directly into the insect blood stream by their nematode vectors, they produce a range of toxi ... | 2007 | 17207509 |
| host-plant effects the expression of resistance to bacillus thuringiensis kurstaki in trichoplusia ni (hubner): an important factor in resistance evolution. | pathogens are thought to exert strong selection on their hosts leading to increased host resistance. bacillus thuringiensis kurstaki (bkt) is a ubiquitous entomopathogen that has become the mainstay of nonchemical control of lepidopteran pests and thus, the potential exists for the evolution of resistance in targeted host insects. we have studied the expression of btk resistance in the cabbage looper, trichoplusia ni (hubner). for this generalist insect herbivore, three common host plants, tomat ... | 2007 | 17210000 |
| dimer structure of an interfacially impaired phosphatidylinositol-specific phospholipase c. | the crystal structure of the w47a/w242a mutant of phosphatidylinositol-specific phospholipase c (pi-plc) from bacillus thuringiensis has been solved to 1.8a resolution. the w47a/w242a mutant is an interfacially challenged enzyme, and it has been proposed that one or both tryptophan side chains serve as membrane interfacial anchors (feng, j., wehbi, h., and roberts, m. f. (2002) j. biol. chem. 277, 19867-19875). the crystal structure supports this hypothesis. relative to the crystal structure of ... | 2007 | 17213187 |
| knockdown of aminopeptidase-n from helicoverpa armigera larvae and in transfected sf21 cells by rna interference reveals its functional interaction with bacillus thuringiensis insecticidal protein cry1ac. | aminopeptidase-n (apn) and cadherin proteins located at the midgut epithelium of helicoverpa armigera have been implicated as receptors for the cry1a subfamily of insecticidal proteins of bacillus thuringiensis. ligand blot analysis with heterologously expressed and purified h. armigera bt receptor with three closely related cry1a proteins tentatively identified haapn1 as an interacting ligand. however, to date there is no direct evidence of apn being a functional receptor to cry1ac in h. armige ... | 2007 | 17213205 |
| characterization of the highly variable cry gene regions of bacillus thuringiensis strain ly4a3 by pcr-sscp profiling and sequencing. | characterization of cry gene contents can help to predict the insecticidal activities of bacillus thuringiensis isolates and in the searching of new cry genes. pcr-single-strand conformation polymorphism (sscp) profiling and sequencing of the highly variable cry gene regions were used to characterize cry gene content of b. thuringiensis strain ly4a3. the highly variable regions with about 1100 bp in sizes were amplified using a degenerate primer pair for cry genes, ol2(d) and ol5(r). a library o ... | 2007 | 17151960 |
| co-expression of the mosquitocidal toxins cyt1aa and cry11aa from bacillus thuringiensis subsp. israelensis in asticcacaulis excentricus. | the cyt1aa gene from bacillus thuringiensis subsp. israelensis (bti), whose product synergizes other mosquitocidal toxins, and functions as a repressor of resistance developed by mosquitoes against bacilli insecticides, was introduced into the aquatic gram-negative bacterium asticcacaulis excentricus alongside the cry11aa gene. the genes were introduced as an operon, but although mrna was detected for both genes, no cyt1aa toxin was detected. both proteins were expressed using a construct in whi ... | 2007 | 17160360 |
| a gene encoding alanine racemase is involved in spore germination in bacillus thuringiensis. | alanine racemase is a major component of the exosporium of bacillus cereus spores. a gene homologous to that of alanine racemase (alra) was cloned from bacillus thuringiensis subsp. kurstaki, and rt-pcr showed that alra was transcribed only in the sporulating cells. disruption of alra did not affect the growth and sporulation of b. thuringiensis, but promoted l-alanine-induced spore germination. when the spore germination rate was measured by monitoring dpa release, complementation of the alra d ... | 2007 | 17165028 |
| kinetics of plasmid transfer among bacillus cereus group strains within lepidopteran larvae. | the cry toxin encoding plasmid pht73 was transferred from bacillus thuringiensis subspecies kurstaki kt0 to six b. cereus group strains in three lepidopteran (spodoptera exigua, plutella xyllostella and helicoverpa armigera) larvae by conjugation. the conjugation kinetics of the plasmid was precisely studied during the larval infection using a new protocol. the infections were performed with both vegetative and sporulated strains. however, larval death only occurred when infections were made wit ... | 2007 | 17216168 |
| fusion of the genes for ahl-lactonase and s-layer protein in bacillus thuringiensis increases its ability to inhibit soft rot caused by erwinia carotovora. | two genes, ctc and ctc2, responsible for surface layer (s-layer) protein synthesis in bacillus thuringiensis ctc, were mutated and resulted in b. thuringiensis tr5. to synthesize and express the n-acyl-homoserine lactonase (ahl-lactonase) in the extracellular space of b. thuringiensis, the aiia ( 4q7 ) gene (an ahl-lactonase gene from b. thuringiensis 4q7), which confers the ability to inhibit plant soft rot disease in b. thuringiensis 4q7, was fused with the upstream sequence of the ctc gene, w ... | 2007 | 17216466 |
| identification of three zwittermicin a biosynthesis-related genes from bacillus thuringiensis subsp. kurstaki strain ybt-1520. | zwittermicin a (zwa) is a novel, broad-spectrum linear aminopolyol antibiotic produced by some bacillus cereus and bacillus thuringiensis. however, only part of its biosynthesis cluster has been identified and characterized from b. cereus uw85. to better understand the biosynthesis cluster of zwa, a bacterial artificial chromosome (bac) library of b. thuringiensis subsp. kurstaki strain ybt-1520, a zwa-producing strain, was constructed. two bac clones, 1f8 and 5e2, were obtained by pcr, which ov ... | 2007 | 17225146 |
| occurrence and persistence of bacillus thuringiensis (bt) and transgenic bt corn cry1ab gene from an aquatic environment. | genetically modified corn crops and suspensions of bacillus thuringiensis (bt) are currently used to control pest infestations of insects of the lepidoptera family. for this purpose, the cry1ab gene coding for protein delta-endotoxin derived from b. thuringiensis kurstaki (btk), which is highly toxic to these insects, was inserted and expressed in corn. the aims of this study were to examine the occurrence and persistence of the cry1ab gene from btk and bt corn in aquatic environments near field ... | 2007 | 16499967 |
| a reliable bioassay procedure to evaluate per os toxicity of bacillus thuringiensis strains against the rice delphacid, tagosodes orizicolus (homoptera: delphacidae). | a reliable bioassay procedure was developed to test ingested bacillus thuringiensis (bt) toxins on the rice delphacid tagosodes orizicolus. initially, several colonies were established under greenhouse conditions, using rice plants to nurture the insect. for the bioassay, an in vitro feeding system was developed for third to fourth instar nymphs. insects were fed through parafilm membranes on sugar (10 % sucrose) and honey bee (1:48 vol/vol) solutions, observing a natural mortality of 10-15 % an ... | 2007 | 19069752 |
| frequency of alleles conferring resistance to the bt toxins cry1ac and cry2ab in australian populations of helicoverpa armigera (lepidoptera: noctuidae). | helicoverpa armigera (hübner) (lepidoptera: noctuidae) is an important lepidopteran pest of cotton (gossypium spp.) in australia and the old world. from 2002, f2 screens were used to examine the frequency of resistance alleles in australian populations of h. armigera to bacillus thuringiensis (bt) crylac and cry2ab, the two insecticidal proteins present in the transgenic cotton bollgard ii. at that time, ingard (expressing cry1ac) cotton had been grown in australia for seven seasons, and bollgar ... | 2007 | 18232402 |
| dipel-selected ostrinia nubilalis larvae are not resistant to transgenic corn expressing bacillus thuringiensis cry1ab. | the survival of ks-sc dipel-resistant and -susceptible european corn borer, ostrinia nubilalis (hübner), was evaluated on different tissues from corn, zea mays l., hybrids, including a nontransgenic and two transgenic corn plants (events mon810 and bt11) expressing high doses of bacillus thuringiensis (bt) cry1ab. the survival of bt-resistant and -susceptible third instars was similar after a 5-d exposure to transgenic plant tissues. survivors eventually died when returned to bt corn tissues, bu ... | 2007 | 18232404 |
| evaluation of transgenic bacillus thuringiensis corn hybrids against cry1ab-susceptible and -resistant sugarcane borer (lepidoptera: crambidae). | a louisiana strain of the sugarcane borer, diatraea saccharalis (f.) (lepidoptera: crambidae), was selected for resistance to the crylab protein of bacillus thuringiensis (bt) by using an f2 screening procedure. survival of bt-resistant, -susceptible, and -heterozygous genotypes of sugarcane borer was evaluated on vegetative and reproductive stages of five non-bt and seven bt field corn, zea mays l., hybrids in a greenhouse study. larval survival was recorded 21 d after infestation of neonates o ... | 2007 | 18232406 |
| resistance to spodoptera frugiperda (lepidoptera: noctuidae) and euxesta stigmatias (diptera: ulidiidae) in sweet corn derived from exogenous and endogenous genetic systems. | field trials using spodoptera frugiperda (j. e. smith) (lepidoptera: noctuidae) and euxesta stigmatias loew (diptera: ulidiidae) were conducted to evaluate resistance and potential damage interactions between these two primary corn, zea mays l., pests against lepidoptera-resistant corn varieties derived from both endogenous and exogenous sources. the endogenous source of resistance was maysin, a c-glycosyl flavone produced in high concentrations in varieties 'zapalote chico 2451' and 'zapalote c ... | 2007 | 18232407 |
| antifungal activities of bacillus thuringiensis isolates on barley and cucumber powdery mildews. | fourteen bacillus thuringiensis isolates having both insecticidal activity and in vitro antifungal activity were selected and tested for in vivo antifungal activity against tomato late blight, wheat leaf rust, tomato gray mold, and barley powdery mildew in growth chambers. all the isolates represented more than 70% disease control efficacy against at least one of four plant diseases. specifically, 12 isolates exhibited strong control activity against barley powdery mildew. under glasshouse condi ... | 2007 | 18167458 |
| a highly pathogenic strain of bacillus thuringiensis serovar kurstaki in lepidopteran pests. | in order to detect and identify the most toxic bacillus thuringiensis strains against pests, we isolated a b. thuringiensis strain (bn1) from balaninus nucum (coleoptera: curculionidae), the most damaging hazelnut pest. bn1 was characterized via morphological, biochemical, and molecular techniques. the isolate was serotyped, and the results showed that bn1 was the b. thuringiensis serovar, kurstaki (h3abc). the scanning electron microscopy indicated that bn1 has crystals with cubic and bipyramid ... | 2007 | 18176540 |
| detection of bacillus cereus virulence factors in commercial products of bacillus thuringiensis and expression of diarrheal enterotoxins in a target insect. | we examined isolates from 4 commercial bioinsecticides based on different strains of bacillus thuringiensis subspecies (kurstaki, israelensis, aizawai, and tenebrionis) for the presence of genes encoding proteins with known enterotoxigenicity (nhe, hbl, cytk, ces) and various other putative virulence genes (piplc, sph, bcet, entfm, ents, entt). the piplc and bcet sequences were present in all the isolates; sph was found in aizawai and israelensis; entfm only in israelensis; and ents in kurstaki, ... | 2007 | 18059560 |
| [association of bioassays and molecular characterization to select new bacillus thuringiensis isolates effective against spodoptera frugiperda (j. e. smith) (lepidoptera: noctuidae)]. | the fall armyworm, spodoptera frugiperda (j. e. smith), is one of the main corn pests and bacillus thuringiensis is important in its control because of its entomopathogenic property. the objective of this study was the molecular characterization of b. thuringiensis isolates for cry1 locus presence and the assessment of the efficiency of these isolates in controlling s. frugiperda caterpillars. gral-cry1 was used in the pcr analyses to confirm the presence of the cry1 locus in 15 isolates. a 3 x ... | 2007 | 18060300 |
| isolation and characterization of strain of bacillus thuringiensis subsp. kenyae containing two novel cry1-type toxin genes. | to identify novel crystal proteins, bacillus thuringiensis 2385-1 was isolated from korean soil samples and characterized. the h-serotype of 2385-1 was identical to that of subsp. kenyae (h4a4c), and its crystal toxin was bipyramidal-shaped. however, 2385-1 showed a much higher toxicity towards plutella xylostella and spodoptera exigua larvae than subsp. kenyae. in addition, the crystal protein profile and plasmid dna pattern of 2385-1 differed from those of subsp. kenyae. to verify the crystal ... | 2007 | 18062228 |
| [cloning, expression and sequence analysis of chia, chib in bacillus thuringiensis subsp. colmeri 15a3]. | two dna fragments encoding chitinase a and b were amplified from total genomic dna of bacillus thuringiensis subsp. colmeri 15a3, and then ligated with pucm-t cloning vector. the recombinant plasmids pucm-chia and pucm-chib were transformed into escherichia coli xl-blue respectively. both chia and chib were successfully expressed in e. coli with their natural promoters independent of any chitin. additionally, the expressed chia and chib could be secreted from e. coli cells. it was proved that tw ... | 2007 | 18062260 |
| [cloning and expression of nematicidal crystal protein gene cry6aa of bacillus thuringiensis]. | on the basis of the sequencing of the n-terminal amino acid of the crystal protein, a nucleotide acid fragment harboring a novel nematicidal gene cry6aa2 was obtained from bacillus thuringiensis strain ybt-1518. this fragment contains two orfs: orf1 and orf2, while a "stem-loop" exists between orf1 and orf2. blast showed the similarity of orf1 nucleotide acid sequence with cry6aa1 is 98%, and has been deposited in the genbank database (acc. no. af499736). the cloning fragment was transferred to ... | 2007 | 18062264 |
| bacillus thuringiensis as a specific, safe, and effective tool for insect pest control. | bacillus thuringiensis (bt) was first described by berliner [10] when he isolated a bacillus species from the mediterranean flour moth, anagasta kuehniella, and named it after the province thuringia in germany where the infected moth was found. although this was the first description under the name b. thuringiensis, it was not the first isolation. in 1901, a japanese biologist, ishiwata shigetane, discovered a previously undescribed bacterium as the causative agent of a disease afflicting silkwo ... | 2007 | 18051264 |
| production of recombinant polyhedra containing cry1ac fusion protein in insect cell lines. | insect cell lines and the control of infection for obtaining the maximum amount of polyhedrin-crylac-polyhedrin fusion protein from bactrus in monolayer and suspension culture systems were tested. growth rates of the trichoplusia ni (high-five) cell line in both culture systems were better than the other insect cell lines, spodoptera fiugiferda (sf-9, sf-21), trichoplusia ni (tn5), and spodoptera exigua (se301). the expression of the fusion protein in a monolayer culture showed that se301 cells ... | 2007 | 18051294 |
| generation of a specific marker to discriminate gacillus anthracis from other bacteria of the bacillus cereus group. | bacillus anthracis is a soil pathogen capable of causing anthrax that is closely related to several environmental species, including b. cereus, b. mycoides, and b. thuringiensis. dna homology studies showed that b. anthracis, b. cereus, b. mycoides, and b. thuringiensis are closely related, with a high sequence homology. to establish a method to specifically detect b. anthracis in situations such as environmental contamination, we initially performed rapd-pcr with a 10-mer random primer and conf ... | 2007 | 18051303 |
| simultaneous detection and identification of bacillus cereus group bacteria using multiplex pcr. | bacillus cereus group bacteria share a significant degree of genetic similarity. thus, to differentiate and identify the bacillus cereus group efficiently, a multiplex pcr method using the gyrb and groel genes as diagnostic markers is suggested for simultaneous detection. the assay yielded a 400 bp amplicon for the groel gene from all the b. cereus group bacteria, and a 253 bp amplicon from b. anthracis, 475 bp amplicon from b. cereus, 299 bp amplicon from b. thuringiensis, and 604 bp amplicon f ... | 2007 | 18051330 |
| identification and molecular characterization of novel cry1-type toxin genes from bacillus thuringiensis k1 isolated in korea. | to clone novel cry1-type genes from the bacillus thuringiensis k1 isolate, about 2.4-kb-long pcr fragments were amplified with two primer sets of atg1-f/n400-r and 1beatg1-f/n400-r. using pcr-rflp, three novel cry1-type genes, cry1-1, cry1-7, and cry1-44, were obtained from b. thuringiensis k1 and the complete coding sequences of these novel genes were analyzed. the cry1-1, cry1-7, and cry1-44 proteins showed maximum similarities of about 78.0%, 99.7%, and 91.0% with the cry1ha1, cry1be1, and cr ... | 2007 | 18051348 |
| aggregates of bacteriophage 0305phi8-36 seed future growth. | lytic bacteriophage 0305phi8-36 forms visually observed aggregates during plaque formation. aggregates intrinsically lower propagation potential. in the present study, the following observations indicate that lost propagation potential is regained with time: (1) aggregates sometimes concentrate at the edge of clear plaques. (2) a semi-clear ring sometimes forms beyond the plaques. (3) formation of a ring is completely correlated with the presence of aggregates at the same angular displacement al ... | 2007 | 18053210 |
| in situ fluorescence microscopy of bacteriophage aggregates. | virus aggregation is analyzed because of its potential use for both classifying viruses and understanding virus ecology and evolution. virus aggregation is, however, problematic because aggregation causes loss of virions during processing for microscopy of any type. thus, here we detect virus aggregation by fluorescence microscopy of wet-mounted dissections of dilute gel-supported plaques (in situ fluorescence microscopy) of a test virus, the long-tail aggregating bacillus thuringiensis bacterio ... | 2007 | 18045325 |
| immigration of bacillus thuringiensis to bean leaves from soil inoculum or distal plant parts. | we addressed the process of immigration of bacillus thuringiensis from soil to leaves and its capacity to grow on bean diffusate medium (bdm), a medium designed to simulate the nutrient composition of the phylloplane. | 2007 | 18045443 |
| prediction-based protein engineering of domain i of cry2a entomocidal toxin of bacillus thuringiensis for the enhancement of toxicity against lepidopteran insects. | issues relating to sustenance of the usefulness of genetically modified first generation bt crop plants in the farmer's field are of great concern for crop scientists. additional biotechnological strategies need to be in place to safeguard the possibility for yield loss of bt crop by other lepidopteran insects that are insensitive to the cry1a toxin, and also against the possibility for emergence of resistant insects. in this respect, cry2a toxin has figured as a prospective candidate to be the ... | 2007 | 18048477 |
| identification and expression of gh-8 family chitosanases from several bacillus thuringiensis subspecies. | the gram-positive spore-forming bacterium, bacillus thuringiensis, a member of the bacillus cereus group, produces chitosanases that catalyze the hydrolysis of chitosan to chitosan-oligosaccharides (cos). although fungal and bacterial chitosanases belonging to other glycoside hydrolase (gh) families have been characterized in a variety of microorganisms, knowledge on the genetics and phylogeny of the gh-8 chitosanases remains limited. nine genes encoding chitosanases were cloned from 29 differen ... | 2007 | 18031332 |
| discovery of crystalline inclusions in bacillus licheniformis that resemble parasporal crystals of bacillus thuringiensis. | crystalline inclusions were discovered in stationary and sporulating cells of the spore-forming bacterium bacillus licheniformis atcc 9945a. as detected by electron microscopy, dying or sporulating bacterial cells contain a single crystal of strikingly large size. the crystals in sporulating cells are located next to nascent spores and can be several times larger than the spores. morphologically, most crystals are rhomboid with uniformly spaced grids. these newly discovered crystalline inclusion ... | 2007 | 18026233 |
| development of a thermostable glucose dehydrogenase by a structure-guided consensus concept. | instability under non-native processing conditions, especially at elevated temperatures, is a major factor preventing the widespread adoption of biocatalysts for industrial synthesis. a crucial distinction of many redox enzymes used to synthesize chiral compounds is the need for cofactors (e.g., nad(p)(h)) for function. because of the prohibitively high prices of nicotinamide cofactors, a robust cofactor-regenerating enzyme is required for the economical synthesis of fine chemicals by biocatalys ... | 2007 | 17990264 |
| comparison of nutritional quality between chinese indica rice with sck and cry1ac genes and its nontransgenic counterpart. | nutritional assessment of transgenic crops used for human food and animal feed is an important aspect of safety evaluations. an insect-resistant rice (irr) was generated by the stable insertion of sck, a modified cowpea trypsin inhibitor gene, and cry1ac, encoding a crystal protein from bacillus thuringiensis into the genome of a common variety of chinese indica rice. the composition of the brown and milled rice grain from the resulted irr line designated liangyou kefeng no. 6 was compared with ... | 2007 | 17995700 |
| temporal detection of cry1ab-endotoxins in coccinellid predators from fields of bacillus thuringiensis corn. | the area planted to genetically engineered crops has increased dramatically in the last ten years. this has generated many studies examining non-target effects of bioengineered plants expressing bacillus thuringiensis endotoxins. to date, most have focused on population-level effects in the field or laboratory evaluation of specific plant-herbivore or plant-herbivore-predator trophic pathways. using a post-mortem enzyme-linked immunosorbent assay, we examined the uptake of cry1ab-endotoxins by p ... | 2007 | 17997879 |
| control of coleopteran insect pests through rna interference. | commercial biotechnology solutions for controlling lepidopteran and coleopteran insect pests on crops depend on the expression of bacillus thuringiensis insecticidal proteins, most of which permeabilize the membranes of gut epithelial cells of susceptible insects. however, insect control strategies involving a different mode of action would be valuable for managing the emergence of insect resistance. toward this end, we demonstrate that ingestion of double-stranded (ds)rnas supplied in an artifi ... | 2007 | 17982443 |
| [analysis of the morphological variants arising during s <--> r dissociation in bacillus thuringiensis]. | physiological, biochemical, and serologic characteristics of 24 clones of r variants spontaneously emerging from the wild type strain of bacillus thuringiensis biotype dendrolimus and of 25 clones of s revertants resulting from the plating of one of the r variants are investigated. it is shown that the efficiency of spore formation is the only characteristic among those investigated which correlated with colony morphology of the s or r type. all r variants were oligo- or asporogenous; they usual ... | 2007 | 17974208 |
| engineering modified bt toxins to counter insect resistance. | the evolution of insect resistance threatens the effectiveness of bacillus thuringiensis (bt) toxins that are widely used in sprays and transgenic crops. resistance to bt toxins in some insects is linked with mutations that disrupt a toxin-binding cadherin protein. we show that susceptibility to the bt toxin cry1ab was reduced by cadherin gene silencing with rna interference in manduca sexta, confirming cadherin's role in bt toxicity. native cry1a toxins required cadherin to form oligomers, but ... | 2007 | 17975031 |
| plant science. the power of the pyramid. | 2007 | 17975032 | |
| exploring the evolution of the bacillus cereus group repeat element bcr1 by comparative genome analysis of closely related strains. | bcr1 is a chromosomal approximately 155 bp repeated element found uniquely and ubiquitously in the bacillus cereus group of gram-positive bacteria; it exhibits several features characteristic of mobile elements, including a variable distribution pattern between strains. here, highly similar bcr1 elements in non-conserved genomic loci are identified in a set of closely related b. cereus and bacillus thuringiensis strains near the bacillus anthracis phylogenetic cluster. it is also shown that bcr1 ... | 2007 | 17975097 |
| the requirement for early exposure of haemonchus contortus larvae to bacillus thuringiensis for effective inhibition of larval development. | the potential for a nematocidal bacillus thuringiensis (bt) to target the free-living larval stages of haemonchus contortus was examined using in vitro larval development and migration assays. bt toxicity in larval development assays decreased as the time period between egg hatch and initial exposure to the bt was increased; a time lag of 48 h resulted in a 350-fold increase in the ic(50) (from 2.6 ng/ml to 910 ng/ml). the effects on larval migration largely paralleled the effects on larval deve ... | 2007 | 17951006 |
| characterization, n-terminal sequencing and classification of cerein mrx1, a novel bacteriocin purified from a newly isolated bacterium: bacillus cereus mrx1. | to purify and characterize the bacteriocin produced by strain mrx1. | 2007 | 17953573 |
| toxins in transgenic crop byproducts may affect headwater stream ecosystems. | corn (zea mays l.) that has been genetically engineered to produce the cry1ab protein (bt corn) is resistant to lepidopteran pests. bt corn is widely planted in the midwestern united states, often adjacent to headwater streams. we show that corn byproducts, such as pollen and detritus, enter headwater streams and are subject to storage, consumption, and transport to downstream water bodies. laboratory feeding trials showed that consumption of bt corn byproducts reduced growth and increased morta ... | 2007 | 17923672 |
| control of arbovirus vector verrallina funerea (diptera: culicidae) in southeast queensland, australia. | in australia, the brackish water mosquito verrallina funerea (theobald) (diptera: culicidae) is a serious pest and vector of ross river and barmah forest viruses in coastal areas in the northeast of the continent. we report on the first extensive evaluation of the efficacy of various pesticides against this species, including laboratory dose-response assays and small plot field trials. in the laboratory, ve. funerea was susceptible to temephos (abate 100e) (lethal concentration, 95% endpoint [lc ... | 2007 | 17972627 |
| using stable isotope analysis to examine fall armyworm (lepidoptera: noctuidae) host strains in a cotton habitat. | spodoptera frugiperda (j.e. smith) (lepidoptera: noctuidae), or fall armyworm, is an important agricultural pest of several crops in the western hemisphere, including cotton (gossypium l.). two morphologically identical host strains of fall armyworm exist that differ in plant host use and habitat distribution. the corn-strain is a primary pest of corn, zea mays l., whereas the rice-strain is the majority population infesting rice (oryza spp.) and turfgrass (cynodon spp.). with the increased use ... | 2007 | 17972634 |
| susceptibility of four species of turfgrass-infesting scarabs (coleoptera: scarabaeidae) to bacillus thuringiensis serovar japonensis strain buibui. | bacillus thuringiensis serovar japonensis strain buibui experimental formulations containing cry8cal delta-endotoxin were evaluated in the field for the control of oriental beetle, anomala orientalis waterhouse; japanese beetle, popillia japonica newman; asiatic garden beetle, maladera castanea (arrow); and european chafer, rhizotrogus majalis (razoumowsky) larvae infesting turfgrasses. in 17 fall applications, control of a. orientalis and p. japonica was achieved at rates as low as 100 g of tox ... | 2007 | 17972638 |
| managing insecticide resistance by mass release of engineered insects. | transgenic crops producing insecticidal toxins are now widely used to control insect pests. the benefits of this method would be lost if resistance to the toxins spread to a significant proportion of the pest population. the primary resistance management method, mandatory in the united states, is the high-dose/ refuge strategy, requiring toxin-free crops as refuges near the insecticidal crops, and the use of toxin doses sufficiently high to kill insects heterozygous for a resistance allele, ther ... | 2007 | 17972643 |
| susceptibility of anthonomus grandis (cotton boll weevil) and spodoptera frugiperda (fall armyworm) to a cry1ia-type toxin from a brazilian bacillus thuringiensis strain. | different isolates of the soil bacterium bacillus thuringiensis produce multiple crystal (cry) proteins toxic to a variety of insects, nematodes and protozoans. these insecticidal cry toxins are known to be active against specific insect orders, being harmless to mammals, birds, amphibians, and reptiles. due to these characteristics, genes encoding several cry toxins have been engineered in order to be expressed by a variety of crop plants to control insectpests. the cotton boll weevil, anthonom ... | 2007 | 17927912 |
| binding characteristics to mosquito-larval midgut proteins of the cloned domain ii-iii fragment from the bacillus thuringiensis cry4ba toxin. | receptor binding plays an important role in determining host specificity of the bacillus thuringiensis cry delta-endotoxins. mutations in domains ii and iii have suggested the participation of certain residues in receptor recognition and insect specificity. in the present study, we expressed the cloned domain ii-iii fragment of cry4ba and examined its binding characteristics to mosquito-larval midgut proteins. the 43-kda cry4ba-domain ii-iii protein over-expressed in escherichia coli as inclusio ... | 2007 | 17927913 |
| improving the insecticidal activity against resistant culex quinquefasciatus mosquitoes by expression of chitinase gene chiac in bacillus sphaericus. | expression of a chitinase gene, chiac, from bacillus thuringiensis in b. sphaericus 2297 using the binary toxin promoter yielded a recombinant strain that was 4,297-fold more toxic than strain 2297 against resistant culex quinquefasciatus. these results show that this chitinase can synergize the toxicity of the binary toxin against mosquitoes and thus may be useful in managing mosquito resistance to b. sphaericus. | 2007 | 17933917 |
| larval gut ph profile in pestiferous chironomus crassicaudatus and glyptotendipes paripes (chironomidae: diptera) in reference to the toxicity potential of bacillus thuringiensis serovar israelensis. | gut ph and ph optimum of amylase were measured in 4th-stage larvae of 2 pestiferous chironomid species, chironomus crassicaudatus and glyptotendipes paripes. the gut ph in both species was close to neutral, varying from 6.7 to 7.4 and 6.9 to 7.6 ph units for c. crassicaudatus and g. paripes, respectively. in both species, slightly alkaline ph values were measured in the anterior part of the mesenteron, whereas slightly acidic ph values were recorded in gastric caecae and the posterior part of me ... | 2007 | 17939521 |
| [deletion of spoivf operon affects the sporulation and the production of crystal in bacillus thuringiensis g03]. | the spoivf operon exists in bacillus universally. two proteins encoded by the spoivf operon are essential for the sporulation of bacillus subtilis. in this study, a spoivf operon disruption mutant g03 (spoivf-), in which the spoivf operon was deleted, was constructed by homologous recombination. the result showed that the mutant strain lost the ability of sporulation. at the same time, the expression of insecticidal crystal protein (icp) was severely reduced in g03 (spoivf-) mutant strain and re ... | 2007 | 17944354 |
| carrier potential properties of bacillus thuringiensis cry1a toxins for a diphtheria toxin epitope. | the n-terminal half or toxic fragment of bacillus thuringiensis cry proteins is comprised of three structural domains. in a previous paper, we showed that this region plays an important role in the immunogenicity of the b. thuringiensis cry proteins. due to this ability and along with their stability it is worthy of investigating whether this region has carrier potential. to approach this, an eight amino acid hydrophobic motif in alpha-helix 7 of wild-type (wt) cry1a toxins was exchanged for a d ... | 2007 | 17949406 |
| adaptive evolution of cry genes in bacillus thuringiensis: implications for their specificity determination. | the cry gene family, produced during the late exponential phase of growth in bacillus thuringiensis, is a large, still-growing family of homologous genes, in which each gene encodes a protein with strong specific activity against only one or a few insect species. extensive studies are mostly focusing on the structural and functional relationships of cry proteins, and have revealed several residues or domains that are important for the target recognition and receptor attachment. in this study, we ... | 2007 | 17893075 |
| structure and specificity of a quorum-quenching lactonase (aiib) from agrobacterium tumefaciens. | n-acyl-l-homoserine lactone (ahl) mediated quorum-sensing regulates virulence factor production in a variety of gram-negative bacteria. proteins capable of degrading these autoinducers have been called "quorum-quenching" enzymes, can block many quorum-sensing dependent phenotypes, and represent potentially useful reagents for clinical, agricultural, and industrial applications. the most characterized quorum-quenching enzymes to date are the ahl lactonases, which are metalloproteins that belong t ... | 2007 | 17900178 |
| report of an expert panel on the reanalysis by of a 90-day study conducted by monsanto in support of the safety of a genetically modified corn variety (mon 863). | mon 863, a genetically engineered corn variety that contains the gene for modified bacillus thuringiensis cry3bb1 protein to protect against corn rootworm, was tested in a 90-day toxicity study as part of the process to gain regulatory approval. this study was reanalyzed by séralini et al. who contended that the study showed possible hepatorenal effects of mon 863. an expert panel was convened to assess the original study results as analyzed by the monsanto company and the reanalysis conducted b ... | 2007 | 17900781 |
| a system for the directed evolution of the insecticidal protein from bacillus thuringiensis. | theoretically, the activity of ab-type toxin molecules such as the insecticidal toxin (cry toxin) from b. thuringiensis, which have one active site and two binding site, is improved in parallel with the binding affinity to its receptor. in this experiment, we tried to devise a method for the directed evolution of cry toxins to increase the binding affinity to the insect receptor. using a commercial t7 phage-display system, we expressed cry1aa toxin on the phage surface as fusions with the capsid ... | 2007 | 17914188 |
| impact of inorganic pollutants perchlorate and hexavalent chromium on efficacy of bacillus sphaericus and bacillus thuringiensis subsp. israelensis against culex quinquefasciatus (diptera: culicidae). | the effects of two widespread environmental pollutants, perchlorate and hexavalent chromium, were assessed on the efficacy of bacillus thuringiensis subsp. israelensis (bti) and bacillus sphaericus (bsph) against fourth instars of culex quinquefasciatus say (diptera: culicidae) in 24-h laboratory bioassays. although 250 mg/liter perchlorate, a level somewhat higher than would be considered ecologically relevant, did not affect the control provided by either larvicide, presence of 1.04 mg/liter h ... | 2007 | 17915513 |
| f2 screen for resistance to a bacillus thuringiensis-maize hybrid in the sugarcane borer (lepidoptera: crambidae). | a novel f2 screening technique was developed for detecting resistance in sugarcane borer, diatraea saccharalis (f.), to transgenic bacillus thuringiensis (bt)-maize expressing the cry1ab insecticidal protein. the f2 screening method involved (i) collecting larvae from maize fields; (ii) establishing two-parent families; (iii) screening f2 neonates for survival on bt-maize leaf tissues; and (iv) confirming resistance on commercial bt-maize plants. with the f2 screening method, 213 iso-line famili ... | 2007 | 17916262 |
| repat, a new family of proteins induced by bacterial toxins and baculovirus infection in spodoptera exigua. | insect larvae spend most of their time eating and the digestive tract is the most crucial barrier for the entrance of many pathogens. in our study, suppression subtractive hybridization (ssh) was used to compare spodoptera exigua midgut gene expression between larvae exposed to the bacillus thuringiensis cry1ca toxin and non-exposed insects. based on the ssh results, full cdna sequences coding for four homologous proteins were obtained. quantitative and semi-quantitative rt-pcr showed the increa ... | 2007 | 17916497 |
| comparative genomics of bacillus thuringiensis phage 0305phi8-36: defining patterns of descent in a novel ancient phage lineage. | the recently sequenced 218 kb genome of morphologically atypical bacillus thuringiensis phage 0305phi8-36 exhibited only limited detectable homology to known bacteriophages. the only known relative of this phage is a string of phage-like genes called bti1 in the chromosome of b. thuringiensis israelensis. the high degree of divergence and novelty of phage genomes pose challenges in how to describe the phage from its genomic sequences. | 2007 | 17919320 |
| differential analysis of bacillus anthracis after px01 plasmid curing and comprehensive data on bacillus anthracis infection in macrophages and glial cells. | bacillus anthracis is a gram-positive bacterial organism responsible for anthrax. this organism has two pathogenic plasmids: px01 and px02. the genetic function of px01, which comprises about 198 kb, is not known, except for a region called the pathogenic island, which contains three genes-pag, lef, and cya-that code for three toxic proteins. a 2-d difference gel electrophoresis (2-d dige) system was used to verify the existence of proteins controlled by the px01 plasmid, and protein regulation ... | 2007 | 17880004 |
| development and characterization of a continuous cell line, afkm-on-h, from hemocytes of the european corn borer ostrinia nubilalis (hübner) (lepidoptera, pyralidae). | the corn borer, ostrinia nubilalis, is a very important pest in different countries, and the in vitro system of the insect could be a useful tool for isolation and characterization of the pathogens and physiological responses of the insect. in this context, a cell line was derived from the hemocytes of the european corn borer and was named afkm-on-h for, respectively, o. nubilalis, armand frappier, king mongkut institutes, and hemocytes. this cell line was initiated and maintained in ex-cell 400 ... | 2007 | 17846857 |
| field trials with tank mixtures of bacillus thuringiensis subsp. israelensis and bacillus sphaericus formulations against culex pipiens larvae in septic tanks in antalya, turkey. | efficacy of tank mixtures of commercial bacillus thuringiensis subsp. israelensis (bti) and bacillus sphaericus (bs) water-dispersable granule (wdg) formulations was evaluated in septic tanks, against culex pipiens l. (diptera: culicidae) larvae. vectolex wdg (bs) + vectobac wdg (bti) were evaluated at various ratios from 488 g/ha vectolex + 250 g/ha vectobac up to 3,000 g/ha of each. all applications and ratios delivering vectolex wdg at a rate equal to or greater than 988 g/ha provided more th ... | 2007 | 17847848 |
| cloning and characterization of pbmb9741, a native plasmid of bacillus thuringiensis subsp. kurstaki strain ybt-1520. | a native plasmid of bacillus thuringiensis subsp. kurstaki strain ybt-1520 named pbmb9741 has been successfully cloned, sequenced, and characterized. twelve open reading frames of at least 50 amino acids were identified. blast search indicated that three of them encode conserved proteins involved in conjugative mobilization, replication initiation, and transcription regulation. the orf6 located within a 2.2-kb minimal replication region was predicted to encode a replication protein. an homologou ... | 2007 | 17849163 |
| effect of age and mating status on adult european corn borer (lepidoptera: crambidae) dispersal from small-grain aggregation plots. | the european corn borer, ostrinia nubilalis (hübner) (lepidoptera: crambidae), is often controlled with genetically modified corn, zea mays l., hybrids (bacillus thuringiensis [bt] corn) in the united states. if bt-resistant insects are detected in the field, mitigation-remediation tactics must be implemented to sustain the efficacy of insecticidal, transgenic corn. mass releasing laboratory-reared, susceptible adults near aggregation sites to mate with locally emerging resistant adults is a pos ... | 2007 | 17849859 |
| influence of plant severing on movement of ostrinia nubilalis larvae in zea mays hybrid seed production fields. | genetically engineered corn hybrids that contain a cry gene from the bacterium bacillus thuringiensis berliner (bt) are gaining popularity for controlling the corn pest ostrinia nubilalis (hübner). continuous use of bt corn, however, could select for o. nubilalis that are resistant to this corn. monitoring for insect resistance is important, because it could help maintain the bt technology. a possible monitoring method is to collect larval insects in commercial drying bins after harvest from bt ... | 2007 | 17849861 |
| feeding behavior and growth of corn earworm (lepidoptera: noctuidae) larvae on bacillus thuringiensis-treated (dipel 4l) and untreated meridic diet. | the effect of dipel 4l in artificial diet on feeding behavior, occurrence on a specific diet, and growth of corn earworm, helicoverpa zea (boddie) (lepidoptera: noctuidae), was assessed in short-term tests. third-, fourth-, and fifth-stage laboratory-reared and feral corn earworm larvae were evaluated. arenas used for each assay included a non-dipel diet, dipel-containing diet, and a combination of the two diets. larval activity was observed immediately after exposure to diet and at 6 and 18 h f ... | 2007 | 17849874 |
| effects of proportion and configuration of bacillus thuringiensis cotton on pest abundance, damage, and yield. | bacillus thuringiensis (bt) transgenic cotton, gossypium hirsutum l., kills several economically important pests, reducing injury and increasing yields. refuges of non-bt cotton are currently planted with bt cotton in different designs to slow pest resistance evolution. to compare the effects of differences in bt/non-bt plant heterogeneity found in different refuge designs on square (flower bud) damage, abscissions, sap-feeding herbivore densities, and yield in cotton, four types of 24-row cotto ... | 2007 | 17849898 |
| bacillus thuringiensis serovariety israelensis and bacillus sphaericus for mosquito control. | since the discovery of bacillus thuringiensis (berliner) serovariety israelensis de barjac (bti) and efficacious isolates of bacillus sphaericus neide, formulations of these bacteria have become the predominant non-chemical means employed for control of mosquito larvae at several locations in the united states and other countries. an overview of developments in the past 20 years is presented in this chapter regarding the toxins of bti and b. sphaericus, their modes of action, efficacy and factor ... | 2007 | 17853604 |
| developing recombinant bacteria for control of mosquito larvae. | genetic engineering techniques have been used to significantly improve mosquito larvicides based on the bacteria bacillus thuringiensis (bt) subsp. israelensis (bti) and bacillus sphaericus (bs). these new larvicides hold excellent promise for providing better and more cost-effective control of nuisance mosquitoes and vectors of important diseases, including the anopheline vectors of malaria and culicine vectors responsible for filariasis and viral encephalitides. the toxicity of bti and bs is d ... | 2007 | 17853605 |
| first example of 5/6-o-linked pseudosaccharides: synthesis of bicyclic nucleosides containing azido or extended carbohydrate moiety. | treatment of the d-glucose-derived substrate 1 with sodium hydride in tetrahydrofuran provided 3,6-anhydro monosaccharide 2, along with the 5,6-ether linked pseudodisaccharide 3, and pseudotrisaccharide 4. however, reaction of 1 with sodium ethoxide in ethanol afforded 2 as the sole product, elaborated to the bicyclic azidonucleosides 9 and 16. acetylated bicyclic nucleosides 17-19 with extended carbohydrate residues have been synthesized from 3. | 2007 | 17854784 |
| identification of vip3a-type genes from bacillus thuringiensis strains and characterization of a novel vip3a-type gene. | to search for novel vip3a proteins for controlling insect pests. | 2007 | 17868317 |
| light scattering sensing detection of pathogens based on the molecular recognition of immunoglobulin with cell wall-associated protein a. | in this contribution, we report a rapid optical detection method of pathogens using staphylococcus aureus (s. aureus) as the model analyte based on the molecular recognition of immunoglobulin with cell wall-associated protein a (spa). it was found that the molecular recognition of human immunoglobulin (igg) with protein a on the cell wall of s. aureus on glass slide sensing area could result in strong surface enhanced light scattering (sels) signals, and the sels intensity (deltai) increases pro ... | 2007 | 17870291 |
| iteron-binding orf157 and ftsz-like orf156 proteins encoded by pbtoxis play a role in its replication in bacillus thuringiensis subsp. israelensis. | we recently identified a minireplicon of pbtoxis from bacillus thuringiensis subsp. israelensis that contained an operon encoding two novel proteins (orf156 and orf157), both of which are required for replication. orf157 contains a helix-turn-helix motif and shares no homology with known plasmid replication proteins (rep), and orf156 contains the signature motif present in ftsz/tubulin proteins, the latter of which are known to function in cell division and chromosome segregation. here we show t ... | 2007 | 17873046 |
| effect of the chitin binding domain deletion from bacillus thuringiensis subsp. kurstaki chitinase chi255 on its stability in escherichia coli. | bacillus thuringiensis subsp. kurstaki bupm255 secretes a chitobiosidase chi255 having an expected molecular weight of 70.665 kda. when the corresponding gene, chi255, was expressed in e. coli, the active form, extracted from the periplasmic fraction of e. coli/pbadchi255, was of about 54 kda, which suggested that chi255 was excessively degraded by the action of e. coli proteases. therefore, in vitro progressive c-terminal chi255 deleted derivatives were constructed in order to study their stabi ... | 2007 | 17873409 |
| transgenic bacillus thuringiensis (bt) cotton (gossypium hirsutum) allomone response to cotton aphid, aphis gossypii, in a closed-dynamics co(2) chamber (cdcc). | allocation of allomones of transgenic bacillus thuringiensis gossypium hirsutum (bt cotton) (cv. gk-12) and non-bt-transgenic cotton (cv. simian-3) grown in elevated co(2) in response to infestation by cotton aphid, aphis gossypii glover, was studied in a closed-dynamics co(2) chamber. significant increases in foliar condensed tannin and carbon/nitrogen ratio for gk-12 and simian-3 were observed in elevated co(2) relative to ambient co(2,) as partially supported by the carbon nutrient balance hy ... | 2007 | 17805479 |
| improving toxicity of bacillus thuringiensis strain contains the cry8ca gene specific to anomala corpulenta larvae. | the cry8c-type gene designated cry8ca2, which was cloned and sequenced from a bacillus thuringiensis isolate hbf-1 in china, consisted of an open reading frame of 3483 bp encoding a protein of 1160 amino-acid residues. sequence analysis showed that the cry8ca2 protoxin of 130.5 kda had 99.9% sequence homology with the previously reported cry8ca1 protein, with one mismatch between the two amino-acid sequences. when the cry8ca2 toxin was expressed in a crystal-negative strain of b. thuringiensis ( ... | 2007 | 17805927 |
| [expression and insecticidal activity of a novel gene cry2ab4 from bacillus thuringiensis strain b-pr-88]. | the full length cry2ab gene was cloned by pcr-rflp method from bt strain b-pr-88, which was isolated in china with high toxicity to the lepidopteran insect pests. nucleic acid sequence analysis showed that this gene was 1902 base pairs encoding 633 amino acids. this cry gene was named cry2ab4 as a novel gene by bacillus thuringiensis delta endotoxin nomenclature committee. the full open reading frame sequence of the cry2ab4 gene was amplified with a pair of pcr primers l2ab5/l2ab3 designed accor ... | 2007 | 17822035 |
| mutated cadherin alleles from a field population of helicoverpa armigera confer resistance to bacillus thuringiensis toxin cry1ac. | the cotton bollworm helicoverpa armigera is the major insect pest targeted by cotton genetically engineered to produce the bacillus thuringiensis toxin (transgenic bt cotton) in the old world. the evolution of this pest's resistance to b. thuringiensis toxins is the main threat to the long-term effectiveness of transgenic bt cotton. a deletion mutation allele (r(1)) of a cadherin gene (ha_btr) was previously identified as genetically linked with cry1ac resistance in a laboratory-selected strain ... | 2007 | 17827322 |
| a novel cadherin-like gene from western corn rootworm, diabrotica virgifera virgifera (coleoptera: chrysomelidae), larval midgut tissue. | a cadherin-like gene associated with larval midgut tissues was cloned from western corn rootworm (diabrotica virgifera virgifera: coleoptera), an economically important agricultural pest in north america and europe and the primary target pest species for corn hybrids expressing cry3 toxins from bacillus thuringiensis (bt). the full-length cdna (5371 bp in length) encodes an open reading frame for a 1688 amino acid polypeptide. the putative protein has similar architecture to cadherin-like protei ... | 2007 | 17725800 |
| effect of insect larval midgut proteases on the activity of bacillus thuringiensis cry toxins. | to test the possibility that proteolytic cleavage by midgut juice enzymes could enhance or inhibit the activity of bacillus thuringiensis insecticidal toxins, once activated, the effects of different toxins on the membrane potential of the epithelial cells of isolated manduca sexta midguts in the presence and absence of midgut juice were measured. while midgut juice had little effect on the activity of cry1aa, cry1ac, cry1ca, cry1ea, and r233a, a mutant of cry1aa from which one of the four salt ... | 2007 | 17693568 |
| univalent binding of the cry1ab toxin of bacillus thuringiensis to a conserved structural motif in the cadherin receptor bt-r1. | the cry1ab toxin produced by bacillus thuringiensis (bt) exerts insecticidal action upon binding to bt-r1, a cadherin receptor localized in the midgut epithelium of the tobacco hornworm manduca sexta [dorsch, j. a., candas, m., griko, n. b., maaty, w. s., midboe, e. g., vadlamudi, r. k., and bulla, l. a., jr. (2002) cry1a toxins of bacillus thuringiensis bind specifically to a region adjacent to the membrane-proximal extracellular domain of bt-r1 in manduca sexta: involvement of a cadherin in th ... | 2007 | 17696320 |
| parasporin-2ab, a newly isolated cytotoxic crystal protein from bacillus thuringiensis. | a novel crystal protein that exhibited potent cytotoxicity against human leukemic t-cells was cloned from the bacillus thuringiensis tk-e6 strain. the protein, designated as parasporin-2ab (ps2ab), was a polypeptide of 304 amino acid residues with a predicted molecular weight of 33,017. the deduced amino acid sequence of ps2ab showed significant homology (84% identitiy) to parasporin-2aa (ps2aa) from the b. thuringiensis a1547 strain. upon processing of ps2ab with proteinase k, the active form o ... | 2007 | 17700988 |
| mtx toxins synergize bacillus sphaericus and cry11aa against susceptible and insecticide-resistant culex quinquefasciatus larvae. | two mosquitocidal toxins (mtx) of bacillus sphaericus, which are produced during vegetative growth, were investigated for their potential to increase toxicity and reduce the expression of insecticide resistance through their interactions with other mosquitocidal proteins. mtx-1 and mtx-2 were fused with glutathione s-transferase and produced in escherichia coli, after which lyophilized powders of these fusions were assayed against culex quinquefasciatus larvae. both mtx proteins showed a high le ... | 2007 | 17704274 |
| an adam metalloprotease is a cry3aa bacillus thuringiensis toxin receptor. | bacillus thuringiensis insecticidal proteins toxic action relies on the interaction with receptor molecules on insect midgut target cells. here, we describe an adam metalloprotease as a novel type of b. thuringiensis toxin receptor on the basis of the following data: (i) by ligand blot and n-terminal analysis, we detected a colorado potato beetle cry3aa toxin binding molecule that shares homology with an adam10 metalloprotease; (ii) colorado potato beetle brush border membrane vesicles display a ... | 2007 | 17714689 |
| effects of cultivation of genetically modified bt maize on epigeic arthropods (araneae; carabidae). | a field study was conducted in germany to determine the possible effects of transgenic maize cultivation on nontarget epigeic predator organisms. during the growing period of 2001-2003, the activity abundances of spiders and carabid beetles were recorded and compared in three treatments: (1) bt-maize (mon 810) expressing the cry1ab protein from bacillus thuringiensis (berliner), (2) an isogenic variety, and (3) the isogenic variety treated with insecticide. all three treatments were replicated i ... | 2007 | 17716489 |
| comparative safety testing of genetically modified foods in a 90-day rat feeding study design allowing the distinction between primary and secondary effects of the new genetic event. | this article discusses the wider experiences regarding the usefulness of the 90-day rat feeding study for the testing of whole foods from genetically modified (gm) plant based on data from a recent eu-project [poulsen, m., schrøder, m., wilcks, a., kroghsbo, s., lindecrona, r.h., miller, a., frenzel, t., danier, j., rychlik, m., shu, q., emami, k., taylor, m., gatehouse, a., engel, k.-h., knudsen, i., 2007a. safety testing of gm-rice expressing pha-e lectin using a new animal test design. food c ... | 2007 | 17719159 |