Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| domain ii loop 3 of bacillus thuringiensis cry1ab toxin is involved in a "ping pong" binding mechanism with manduca sexta aminopeptidase-n and cadherin receptors. | bacillus thuringiensis cry toxins are used worldwide as insecticides in agriculture, in forestry, and in the control of disease transmission vectors. in the lepidopteran manduca sexta, cadherin (bt-r(1)) and aminopeptidase-n (apn) function as cry1a toxin receptors. the interaction with bt-r(1) promotes cleavage of the amino-terminal end, including helix alpha-1 and formation of prepore oligomer that binds to apn, leading to membrane insertion and pore formation. loops of domain ii of cry1ab toxi ... | 2009 | 19808680 |
| cadherin fragments from anopheles gambiae synergize bacillus thuringiensis cry4ba's toxicity against aedes aegypti larvae. | a peptide from cadherin agcad1 of anopheles gambiae larvae was reported as a synergist of bacillus thuringiensis subsp. israelensis cry4ba's toxicity to the anopheles mosquito (g. hua, r. zhang, m. a. abdullah, and m. j. adang, biochemistry 47:5101-5110, 2008). we report that cr11 to the membrane proximal extracellular domain (mped) (cr11-mped) and a longer peptide, cr9 to cr11 (cr9-11), from agcad1 act as synergists of cry4ba's toxicity to aedes aegypti larvae, but a diabrotica virgifera virgif ... | 2009 | 19801487 |
| identification of a polymorphic collagen-like protein in the crustacean bacteria pasteuria ramosa. | pasteuria ramosa is a spore-forming bacterium that infects daphnia species. previous results demonstrated a high specificity of host clone/parasite genotype interactions. surface proteins of bacteria often play an important role in attachment to host cells prior to infection. we analyzed surface proteins of p. ramosa spores by two-dimensional gel electrophoresis. for the first time, we prove that two isolates selected for their differences in infectivity reveal few but clear-cut differences in p ... | 2009 | 19770039 |
| dispersal and mating behavior of diabrotica virgifera virgifera (coleoptera: chrysomelidae) in bt cornfields. | understanding of the mating and dispersal behavior of the western corn rootworm, diabrotica virgifera virgifera (leconte), is essential to predicting potential resistance to bt corn technologies recently deployed to combat this pest. to quantify movement of male beetles, field studies were conducted during 2006 and 2007 in commercial bt cornfields that included the environmental protection agency-mandated 20% refuge acreage. wing traps containing a single virgin female beetle were placed along t ... | 2009 | 19791612 |
| three-year field monitoring of cry1f, event das-01507-1, maize hybrids for nontarget arthropod effects. | field studies were conducted over a 3-yr period to investigate the potential effects of cultivating transgenic maize hybrids containing a cry1f insect-resistant protein on nontarget arthropod abundance. the narrow spectrum of activity of cry1f against a subset of lepidopteran pest species would not suggest broad-spectrum effects on nontarget arthropods. however, because of the insecticidal nature of bt proteins, an alternate hypothesis is that some nontargets may be affected by exposure to the p ... | 2009 | 19791625 |
| [research of the bt crop biomass dynamics upon the invasion of bt-resistant pests. a mathematical model]. | the results of simulations of some consequences of the invasion of bt-resistant pests into an agricultural ecosystem containing a bt crop are presented. it is shown that the invasion of bt-resistant pests leads to changes in the plant biomass dynamics, a decrease in the bt crop production, and the deterioration of the predictability of the bt crop production. we show that the parameter values at which the badly predictable bt crop production takes place, occupy a minor area in the model paramete ... | 2009 | 19795797 |
| correlative effect on the toxicity of three surface-exposed loops in the receptor-binding domain of the bacillus thuringiensis cry4ba toxin. | surface-exposed loop residues, pro(389) (beta(6)-beta(7) loop), glu(417) (beta(8)-beta(9) loop), tyr(455) and asn(456) (beta(10)-beta(11) loop), in the receptor-binding domain of the bacillus thuringiensis cry4ba toxin have been previously demonstrated to be crucial for toxicity. herein, five combinations of two-loop mutants, p389a/e417a (beta(6)-beta(7)/beta(8)-beta(9) loops), p389a/y455a, p389a/n456a (beta(6)-beta(7)/beta(10)-beta(11) loops), e417a/y455a and e417a/n456a (beta(8)-beta(9)/beta(1 ... | 2009 | 19765086 |
| transgenic rice plants expressing a modified cry1ca1 gene are resistant to spodoptera litura and chilo suppressalis. | nucleotide sequence encoding the truncated insecticidal cry1ca1 protein from bacillus thuringiensis was extensively modified based on the codon usage of rice genes. the overall g + c contents of the synthetic cry1ca1 coding sequence were raised to 65% with an additional bias of enriching for g and c ending codons as preferred by monocots. the synthetic gene was introduced into the chinese japonica variety, xiushui 11, by agrobacterium-mediated transformation. transgenic rice plants harboring thi ... | 2009 | 19760523 |
| cloning and molecular characterization of a novel rolling-circle replicating plasmid, pk1s-1, from bacillus thuringiensis subsp. kurstaki k1. | bacillus thuringiensis, an entomopathogenic bacterium belonging to the b. cereus group, harbors numerous extra-chromosomal dna molecules whose sizes range from 2 to 250 kb. in this study, we used a plasmid capture system (pcs) to clone three small plasmids from b. thuringiensis subsp. kurstaki kl which were not found in b. thuringiensis subsp. kurstaki hd-1, and determined the complete nucleotide sequence of plasmid pkls-1 (5.5 kb). of the six putative open reading frames (orf2-orf7) in pkls-1, ... | 2009 | 19763421 |
| commercialized gm crops and yield. | 2009 | 19741630 | |
| anopheles gambiae alkaline phosphatase is a functional receptor of bacillus thuringiensis jegathesan cry11ba toxin. | alkaline phosphatases (alps, ec 3.1.3.1) isolated from lepidopteran and dipteran species are identified as receptors for cry1ac and cry11aa toxins, respectively [jurat-fuentes, j. l., and adang, m. j. (2004) eur. j. biochem. 7, 3127-3135; fernandez, l. e., et al. (2006) biochem. j. 396, 77-84]. in our study, an alkaline phosphatase cdna (agalp1) was cloned from the midgut of anopheles gambiae larvae. the encoded 63 kda protein has a predicted glycosylphosphatidylinositol (gpi) anchor omega-site ... | 2009 | 19747003 |
| reversed-phase high-performance liquid chromatography-electrospray mass spectrometry profiling of transgenic and non-transgenic maize for cultivar characterization. | a reversed-phase high-performance liquid chromatography-electrospray mass spectrometry (rp-hplc-esi-ms (ion trap)) method is developed, for the first time, for profiling transgenic and non-transgenic maize with the aim of cultivar characterization. to optimize chromatographic conditions the following parameters were studied: column, gradient, and ion-pairing reagent. moreover, the influence in the ms signal of the variation of the capillary voltage and the accumulated ions in the trap was also s ... | 2009 | 19748098 |
| surface display of heterologous proteins in bacillus thuringiensis using a peptidoglycan hydrolase anchor. | abstract: | 2009 | 19754974 |
| aedes aegypti cadherin serves as a putative receptor of the cry11aa toxin from bacillus thuringiensis subsp. israelensis. | cry11aa of bacillus thuringiensis subsp. israelensis is the most active toxin to aedes aegypti in this strain. we previously reported that, in addition to a 65 kda gpi (glycosylphosphatidylinositol)-anchored alp (alkaline phosphatase), the toxin also binds a 250 kda membrane protein. since this protein is the same size as cadherin, which in lepidopteran insects is an important cry toxin receptor, we developed an anti-aaecad antibody. this antibody detects a 250 kda protein in immunoblots of larv ... | 2009 | 19732034 |
| biosynthesis and transcriptional analysis of thurincin h, a tandem repeated bacteriocin genetic locus, produced by bacillus thuringiensis sf361. | thurincin h, a bacteriocin produced by bacillus thuringiensis sf361 isolated from honey, strongly inhibited the growth of bacillus cereus f4552. the bacteriocin was purified by 65% ammonium sulfate precipitation of the culture supernatant, followed by octyl-sepharose cl-4b and reverse-phase hplc. the molecular mass of the bacteriocin was determined to be 3139.51 da and the 14 amino acids of the bacteriocin at the n-terminus were identified. the complete amino acid sequence of mature thurincin h ... | 2009 | 19732155 |
| diversity of bacillus thuringiensis strains isolated from citrus orchards in spain and evaluation of their insecticidal activity against ceratitis capitata. | a survey of bacillus thuringiensis (berliner) strains isolated from spanish citrus orchards has been performed, and the strains were tested for insecticidal activity against the mediterranean fruit fly ceratitis capitata (wiedemann), a key citrus pest in spain. from a total of 150 environmental samples, 376 isolates were selected, recording a total b. thuringiensis index of 0.52. the collection was characterized by means of phase-contrast microscopy, sds-page, and pcr analysis with primer pairs ... | 2009 | 19734711 |
| promoters of crystal protein genes do not control crystal formation inside exosporium of bacillus thuringiensis ssp. finitimus strain ybt-020. | most bacillus thuringiensis parasporal crystals separate from spores after sporulation. a special phenomenon called spore-crystal association (sca) occurs in a few subspecies (e.g. ssp. finitimus) where enclosed crystals are associated with spores. in this study, the involvement of crystal protein gene promoters in sca was investigated. two crystal protein genes, cry26aa and cry28aa, were isolated from subspecies finitimus strain ybt-020, and each or both were then transferred to acrystalliferou ... | 2009 | 19735465 |
| a medium for the production of biopesticides (bacillus sphaericus and bacillus thuringiensis subsp. israelensis) in mosquito control. | chicken feathers, discarded as bioorganic wastes from poultry processing industries, are rich in keratin (structural protein). deoiled rice bran (drb), in contrast, is an agrowaste product consisting of protein, fiber, and carbohydrates. this study highlights a new medium for producing biopesticides from these bioorganic wastes, by culturing bacillus sphaericus (bs) and b. thuringiensis subsp. israelensis (bti), to synthesize mosquitocidal toxins. biochemical studies indicated that the amount of ... | 2009 | 19736752 |
| efficacy of cry1ac:cry1f proteins in cotton leaf tissue against fall armyworm, beet armyworm, and soybean looper (lepidoptera: noctuidae). | cotton, gossypium hirsutum l., plants expressing cry1ac and cry1f insecticidal crystal proteins of bacillus thuringiensis berliner (bt) were evaluated against selected lepidopteran pests including fall armyworm, spodoptera frugiperda (j. e. smith), beet armyworm, spodoptera exigua (hübner), and soybean looper, pseudoplusia includens (walker). studies were conducted in a range of environments, challenging various cotton tissue types from several varieties containing a combination of cry1ac and cr ... | 2009 | 19736762 |
| response of heliothis virescens (lepidoptera: noctuidae) strains to bacillus thuringiensis cry1ac incorporated into different insect artificial diets. | susceptibility to the cry1ac toxin from bacillus thuringiensis in tobacco budworm, heliothis virescens (f.) (lepidoptera: noctuidae), is usually measured by performing bioassays under laboratory conditions. accurate comparison of cry1ac susceptibility among h. virescens samples conducted in different places is challenged by several important methodological aspects, especially if different insect artificial diets are used to perform bioassays. in this study, we compared cry1ac susceptibility of f ... | 2009 | 19736774 |
| impact of mon863 transgenic roots is equivalent on western corn rootworm larvae for a wide range of maize phenologies. | the effects of maize, zea mays l., phenology on establishment, damage, and adult emergence of the western corn rootworm, diabrotica virgifera virgifera leconte, on mon863 transgenic maize expressing the cry3bb1 protein and its isoline was evaluated in field trials in 2002 and 2003. as expected, plant damage, western corn rootworm larval recovery, and adult emergence were significantly lower on mon863 than isoline maize. the average weight of larvae and adults recovered from mon863 and isoline ma ... | 2009 | 19736775 |
| evaluation of transgenic soybean exhibiting high expression of a synthetic bacillus thuringiensis cry1a transgene for suppressing lepidopteran population densities and crop injury. | several transgenic lines of soybean, glycine max (l.) merr., expressing a synthetic cry1a gene from bacillus thuringiensis (bt), were examined in replicated field trials in 2003-2007 for suppression of naturally occurring population densities of lepidopteran pests and the resultant crop injury that they caused. bt soybean and negative controls (isogenic segregants and parental lines) were evaluated against velvetbean caterpillar, anticarsia gemmatalis (hübner); soybean looper, pseudoplusia inclu ... | 2009 | 19736779 |
| improvement of bacillus thuringiensis bacteriocin production through culture conditions optimization. | bupm4 is a bacillus thuringiensis subsp. kurstaki strain, isolated from tunisian soil, producing an original bacteriocin named bacthuricin f4. the optimization of the latter production conditions was carried out under several physicochemical conditions. it was found that the highest bacteriocin activity was reached at low aeration while bacteriocin synthesis yields were strongly reduced at higher ones. a balance between growth and bacteriocin synthesis, both highly dependent on aeration, was tak ... | 2009 | 19739026 |
| analysis of the region for receptor binding and triggering of oligomerization on bacillus thuringiensis cry1aa toxin. | the determination of the receptor-binding region of cry toxins produced by bacillus thuringiensis is expected to facilitate an improvement in their insecticidal ability through protein engineering. we analyzed the region on cry1aa molecules involved in interactions with the cadherin-like protein receptor btr175 using cysteine-substituted mutant toxins and several synthetic peptides corresponding to the loops in domain 2. in addition, the region necessary to trigger oligomerization was analyzed u ... | 2009 | 19740106 |
| homodimeric alkaline phosphatase located at helicoverpa armigera midgut, a putative receptor of cry1ac contains alpha-galnac in terminal glycan structure as interactive epitope. | helicoverpa armigera causes massive yield loss of various crops globally. bacillus thuringiensis coded cry1ac toxin is effective against the pest. through the present investigation, an alkaline phosphatase type putative receptor of the toxin was identified in the target insect gut bbmv. lectin-ligand immunoblot assay detected the presence of alpha-galnac residue at the nonreducing terminal of the glycan structure in the membrane bound haalp protein which mediates the toxin-receptor interaction. | 2009 | 19714811 |
| genetic similarity of eggplant shoot and fruit borer, leucinodes orbonalis, populations. | shoot and fruit borer, leucinodes orbonalis (guenee) (pyraustidae: lepidoptera), has become a production constraint in all eggplant (solanum melongena linn. [solanaceae])-growing countries. in india, transgenic eggplants expressing bacillus thuringiensis cry toxins have been tested in fields by private- and public-sector agencies. understanding population diversity is important in designing strategies for better pest management. in the present investigation, random-amplified polymorphic dna mark ... | 2009 | 19715478 |
| two epsilon glutathione s-transferase cdnas from the common cutworm, spodoptera litura: characterization and developmental and induced expression by insecticides. | two spodoptera litura glutathione s-transferase cdnas (slgste2 and slgste3) which were cloned from a midgut cdna, encoded two structurally distinct proteins with a predicted molecular mass of 25 and 24kda, respectively. slgste2 and slgste3 were single-copy genes in the s. litura genome and there was no intron within the genes. the transcripts and proteins of slgste2 and slgste3 were predominately present in the midgut of the 5th and 6th instar larvae. the apparent vmax of the purified slgste2 an ... | 2009 | 19715699 |
| an extracytoplasmic function sigma factor controls beta-lactamase gene expression in bacillus anthracis and other bacillus cereus group species. | the susceptibility of most bacillus anthracis strains to beta-lactam antibiotics is intriguing considering that the closely related species bacillus cereus and bacillus thuringiensis typically produce beta-lactamases and the b. anthracis genome harbors two beta-lactamase genes, bla1 and bla2. we show that beta-lactamase activity associated with b. anthracis is affected by two genes, sigp (ba2502) and rsip (ba2503), predicted to encode an extracytoplasmic function sigma factor and an anti-sigma f ... | 2009 | 19717606 |
| gm crops: battlefield. | 2009 | 19727179 | |
| the genome and variation of bacillus anthracis. | the bacillus anthracis genome reflects its close genetic ties to bacillus cereus and bacillus thuringiensis but has been shaped by its own unique biology and evolutionary forces. the genome is comprised of a chromosome and two large virulence plasmids, pxo1 and pxo2. the chromosome is mostly co-linear among b. anthracis strains and even with the closest near neighbor strains. an exception to this pattern has been observed in a large inversion in an attenuated strain suggesting that chromosome co ... | 2009 | 19729033 |
| bacillus thuringiensis serovar mogi (flagellar serotype 3a3b3d), a novel serogroup with a mosquitocidal activity. | the flagellated vegetative cells of the bacillus thuringiensis strain k4 were agglutinated with the h3 reference antiserum and further, agglutinated with 3b and 3d monospecific factor sera but non-reactive for 3c and 3e factor sera. this creates a new serogroup with flagellar antigenic structure of 3a3b3d: b. thuringiensis serovar mogi. the strain k4 showed high activity against dipteran larvae, anopheles sinensis and culex pipienspallens while no lepidopteran toxicity. it produced ovoidal paras ... | 2009 | 19703461 |
| functional interpretation of apn receptor from m.sexta using a molecular model. | insect pests are the major cause of damage to commercially important agricultural crops. the continuous application of synthetic pesticides resulted in severe insect resistance by plants. this causes irreversible damage to the environment. bacillus thuringiensis (bt) emerged as a valuable biological alternative in pest control. however, insect resistance against bt has been reported in many cases. insects develop resistance to insecticides through mechanisms that reduce the binding of toxins to ... | 2009 | 19707293 |
| the expression of a recombinant cry1ac gene with subtilisin-like protease cdep2 gene in acrystalliferous bacillus thuringiensis by red/et homologous recombination. | a novel cdna encoding the subtilisin-like serine protease gene cdep2 was isolated from beauveria bassiana by reverse transcription polymerase chain reaction (rt-pcr). it contained an 1137 bp orf that predicted a protein of 379 amino acids with m = 38863 da and pi = 8.21. in an attempt to improve insecticidal activity, the cdep2 gene and the cry1ac gene from bacillus thuringiensis were co-fused into the vector pht315 as phac-cdep2 plasmid by red/et homologous recombination. the co-fusion gene was ... | 2009 | 19653036 |
| evaluation of three microbial formulations against culex pipiens pipiens larvae in irrigation fields in wroclaw, poland. | two evaluations of microbial mosquito larvicides were conducted in irrigation fields located along the odra river near the city of wroclaw, poland. in the first evaluation, 3 dosages each of bacillus thuringiensis israelensis (bti)--vectobac water dispersible granule (wdg) and vectobac aqueous suspension formulation (12as)--and bacillus sphaericus (bs)--vectolex wdg--were tested against larvae of culex pipiens pipiens. there was little difference between formulations and rates of application bet ... | 2009 | 19653495 |
| larvicidal activity and influence of bacillus thuringiensis var. israelensis on aedes albopictus oviposition in ovitraps during a two-week check interval protocol. | toxicity persistence of bacillus thuringiensis var. israelensis (bti) was evaluated in laboratory and field trials to develop a new protocol for aedes albopictus monitoring. in the laboratory, the residual toxicity of 5 bti formulations was compared using the percentage mortality at days 4, 8, 12, and 16 of culex pipiens larvae exposed for 24 h to bti treatments. the results showed a good performance of all tested formulations (>97% mortality at day 14, for all the formulations), but only vectob ... | 2009 | 19653496 |
| complete sequence of three plasmids from bacillus thuringiensis inta-fr7-4 environmental isolate and comparison with related plasmids from the bacillus cereus group. | bacillus thuringiensis is an insect pathogen used worldwide as a bioinsecticide. it belongs to the bacillus cereus sensu lato group as well as bacillus anthracis and b. cereus. plasmids from this group of organisms have been implicated in pathogenicity as they carry the genes responsible for different types of diseases that affect mammals and insects. some plasmids, like paw63 and pbt9727, encode a functional conjugation machinery allowing them to be transferred to a recipient cell. they also sh ... | 2009 | 19654019 |
| addition of microbially-treated sugar beet residue and a native bacterium increases structural stability in heavy metal-contaminated mediterranean soils. | a mesocosm experiment was conducted to investigate the effect of the addition of aspergillus niger-treated sugar beet waste, in the presence of rock phosphate, and inoculation with a native, metal-tolerant bacterium, bacillus thuringiensis, on the stabilisation of soil aggregates of two mine tailings, with differing ph values, from a semiarid mediterranean area and on the stimulation of growth of piptatherum miliaceum. bacterium combined with organic amendment enhanced structural stability (38% ... | 2009 | 19660785 |
| biological properties of loop-replaced mutants of bacillus thuringiensis mosquitocidal cry4aa. | cry4aa produced by bacillus thuringiensis subsp. israelensis (bti) exhibits a specific toxicity to anopheles, aedes, and culex larvae, which are vectors of serious diseases, and formulations of bti are used worldwide for mosquito control. in general, domain ii of the cry toxin is believed to be important for target specificity, and three loops (loops 1, 2, and 3) in domain ii have been studied extensively. in this report, to analyze the biological functions of loops 1, 2, and 3 of cry4aa, mutant ... | 2009 | 19664548 |
| cadherin gene expression and effects of bt resistance on sperm transfer in pink bollworm. | cadherin proteins bind bacillus thuringiensis (bt) toxins in lepidopteran midguts but their inherent function remains unclear. in pink bollworm, pectinophora gossypiella, three recessive mutations in a cadherin gene (btr) are tightly linked with resistance to bt toxin cry1ac. here we examined patterns of transcription of this gene and the association between cadherin genotype and sperm transfer in pink bollworm. cadherin rna was most abundant in larvae, but was also found in adults and embryos. ... | 2009 | 19666026 |
| an investigation of bacillus thuringiensis in rectal-collected fecal samples of cows. | in order to better understand the range and role of bacillus thuringiensis (bt) and its toxins in nature, we have undertaken a study of bt taken directly from the rectum of 117 cows from 37 farms on the caribbean island of trinidad. thirty-seven fecal samples (32%) were found to contain at least one bt. generally only one or two isolates with a particular crystal morphology were isolated from any one sample, however, a few samples contained more, up to 11 isolates, suggesting post-ingestion ampl ... | 2009 | 19688377 |
| frequency of bt resistance alleles in h. armigera during 2006-2008 in northern china. | helicoverpa armigera is an important lepidopteran pest of cotton in china. from 2002, the frequency of bt resistance alleles and quantitative shifts in larval cry1ac tolerance of field h. armigera population were monitored using bioassays of f(1) and f(2) offspring of isofemale lines from xiajin county of shandong province (an intensive bt cotton planting area) and anci county of hebei province (a multiple-crop system including corn, soybean, peanut, and bt cotton) in northern china. during 2006 ... | 2009 | 19689916 |
| characterization of native bacillus thuringiensis strains and selection of an isolate active against spodoptera frugiperda and peridroma saucia. | twelve bacillus thuringiensis (bt) strains, isolated from larvae and soil samples in argentina, were molecularly and phenotypically characterized and their insecticidal activities against spodoptera frugiperda and peridroma saucia were determined. one isolate--bt rt--produced more than 93% mortality on first instar larvae of both species, which was higher than that produced by the reference strain bt 4d1. bt rt carried a different cry gene profile than bt 4d1. scanning electron microscopy showed ... | 2009 | 19693442 |
| field effectiveness of bacillus thuringiensis israelensis (bti) against aedes (stegomyia) aegypti (linnaeus) in ornamental ceramic containers with common aquatic plants. | this study was undertaken to determine the impact of larvaciding using a bti (bacillus thuringiensis israelensis) formulation (vectobac wg) against aedes aegypti larvae in earthen jars containing aquatic plants. aquatic plants commonly used for landscaping, pistia stratiotes (l.) (liliopsida: araceae) and sagittaria sp. (liliopsida: alismataceae) were placed inside earthen jars filled with 50 l tap water. all earthen jars were treated with bti formulation at 8g/1000l. untreated jars with and wit ... | 2009 | 19696734 |
| cloning and epitope mapping of cry11aa-binding sites in the cry11aa-receptor alkaline phosphatase from aedes aegypti. | cry11aa is the most active bacillus thuringiensis israelensis toxin against aedes aegypti larvae. ae. aegypti alkaline phosphatase (alp) was previously identified as a cry11aa receptor mediating toxicity. here we report the cloning and functional characterization of this ae. aegypti cry11aa-alp receptor. of three alp's cdna clones, the recombinant produced alp1 isoform was shown to bind cry11aa and p1.bbmv peptide phage that specifically binds the midgut alp-cry11aa receptor. an anti-alp1 antibo ... | 2009 | 19697959 |
| identification and characterization of aedes aegypti aminopeptidase n as a putative receptor of bacillus thuringiensis cry11a toxin. | bacillus thuringiensis subsp. israelensis, which is used worldwide to control aedes aegypti larvae, produces cry11aa and other toxins during sporulation. in this study, pull-down assays were performed using biotinylated cry11aa toxin and solubilized brush border membrane vesicles prepared from midguts of aedes larvae. three of the eluted proteins were identified as aminopeptidase n (apn), one of which was a 140 kda protein, named aaeapn1 (aael012778 in vectorbase). this protein localizes to the ... | 2009 | 19698787 |
| parasporin-2 requires gpi-anchored proteins for the efficient cytocidal action to human hepatoma cells. | parasporin-2 (ps2) is a bacillus thuringiensis inclusion protein that reacts intensively with human hepatoma cells. this antitumour toxin oligomerizes at the cell surface via binding to lipid rafts, leading to the cell lysis with typical blebs around peripheral cells. we find here that glycosylphosphatidylinositol (gpi)-anchored proteins are involved in the cytocidal actions. depletion of the cellular cholesterol and loss of sphingolipid in lipid rafts slightly decreased cytolysis by ps2. beyond ... | 2009 | 19646502 |
| genetic basis for alkaline activation of germination in bacillus thuringiensis subsp. israelensis. | differences in activation between spores from strains of bacillus thuringiensis subsp. israelensis with and without the toxin-encoding plasmid pbtoxis are demonstrated. following alkaline activation, the strain bearing pbtoxis shows a significantly greater germination rate. expression of just three genes constituting a previously identified, putative ger operon from this plasmid is sufficient to produce the same phenotype and characterizes this operon as a genetic determinant of alkaline activat ... | 2009 | 19648359 |
| novel and unique diagnostic biomarkers for bacillus anthracis infection. | a search for bacterium-specific biomarkers in peripheral blood following infection with bacillus anthracis was carried out with rabbits, using a battery of specific antibodies generated by dna vaccination against 10 preselected highly immunogenic bacterial antigens which were identified previously by a genomic/proteomic/serologic screen of the b. anthracis secretome. detection of infection biomarkers in the circulation of infected rabbits could be achieved only after removal of highly abundant s ... | 2009 | 19648366 |
| biofilm formation and cell surface properties among pathogenic and nonpathogenic strains of the bacillus cereus group. | biofilm formation by 102 bacillus cereus and b. thuringiensis strains was determined. strains isolated from soil or involved in digestive tract infections were efficient biofilm formers, whereas strains isolated from other diseases were poor biofilm formers. cell surface hydrophobicity, the presence of an s layer, and adhesion to epithelial cells were also examined. | 2009 | 19648377 |
| fluorescence cross sections of bioaerosols and suspended biological agents. | laser-induced fluorescence is used to investigate fluorescence properties of unwashed bacillus thuringiensis and bacillus subtilis spores, ovalbumin, and washed bacteriophage ms2. a fluorescence detector is calibrated to obtain absolute fluorescence cross sections. fluorescence maps of biological aerosols and suspensions are measured at a wide excitation range from 210 to 419 nm and a wide detection range from 315 to 650 nm. the dominant features of the measured spectra are the amino acid peaks, ... | 2009 | 19649034 |
| toward the physiological basis for increased agrotis ipsilon multiple nucleopolyhedrovirus infection following feeding of agrotis ipsilon larvae on transgenic corn expressing cry1fa2. | larvae of the black cutworm, agrotis ipsilon hufnagel, were more susceptible to infection by a. ipsilon multiple nucleopolyhedrovirus (agipmnpv: baculoviridae) after feeding on herculex i, a transgenic corn hybrid expressing the bacillus thuringiensis (bt)-derived toxin cry1fa2 compared to larvae fed on isoline corn. we investigated the physiological basis for increased susceptibility to virus infection following exposure to herculex i by analyzing the midgut ph, gut protease activity and peritr ... | 2009 | 19651136 |
| asymmetrical cross-resistance between bacillus thuringiensis toxins cry1ac and cry2ab in pink bollworm. | transgenic crops producing bacillus thuringiensis (bt) toxins kill some key insect pests and can reduce reliance on insecticide sprays. sustainable use of such crops requires methods for delaying evolution of resistance by pests. to thwart pest resistance, some transgenic crops produce 2 different bt toxins targeting the same pest. this "pyramid" strategy is expected to work best when selection for resistance to 1 toxin does not cause cross-resistance to the other toxin. the most widely used pyr ... | 2009 | 19581574 |
| peritrophic membrane contribution to bt cry d-endotoxin susceptibility in lepidoptera and the effect of calcofluor. | in an effort to determine a reason for differing susceptibilities to bacillus thuringiensis (bt) cry d-endotoxins amongst lepidopteran species, the peritrophic membrane (pm), and a number of agents that target the pm, were investigated to determine their effect on the efficacy of bt toxins. in particular calcofluor is able to disrupt the pm that acts as a barrier to microorganisms. although bt toxins have been shown to traverse the pm in some lepidopteran species, new data shows that toxins can ... | 2009 | 19567227 |
| synthesis and antibacterial activity of some new heterocycles incorporating phthalazine. | 3-(1,4-dioxo-3,4,4e,5,10,10a-hexahydro-1h-5,10-benzeno-benzo[g]phthalazin-2-yl)-3-oxo-propiononitrile (1) was utilized as key intermediate for the synthesis of some new iminocoumarin 2, chromenone 3, aminothiazole 4, triazepine 5a, b and 6, hydrazono-propiononitrile 7, pyridopyrazotriazine 8, monobromo 9, dibromo 10 quinoxaline 11, ketene n,s-acetal 13, ketene s,s-diacetal 17 and 18a, b and methyl dithioate 20 derivatives, respectively. the newly synthesized compounds were characterized by ir, ( ... | 2009 | 19570595 |
| report claims no yield advantage for bt crops. | 2009 | 19587654 | |
| synergistic interactions between cry1ac and natural cotton defenses limit survival of cry1ac-resistant helicoverpa zea (lepidoptera: noctuidae) on bt cotton. | larvae of the bollworm helicoverpa zea (boddie) show some tolerance to bacillus thuringiensis (bt) cry1ac, and can survive on cry1ac-expressing bt cotton, which should increase resistance development concerns. however, field-evolved resistance has not yet been observed. in a previous study, a population of h. zea was selected for stable resistance to cry1ac toxin. in the present study, we determined in laboratory bioassays if larvae of the cry1ac toxin-resistant h. zea population show higher sur ... | 2009 | 19588197 |
| the pattern of toxin genes and expression of diarrheal enterotoxins in bacillus thuringiensis strains isolated from commercial bioinsecticides. | 2009 | 19588259 | |
| a molecular dynamics model of the bt toxin cyt1a and its validation by resonance energy transfer. | cyt1a is a cytolytic toxin from bacillus thuringiensis var. israelensis. a computer model of the toxin in solution was generated and validated by resonance energy transfer (ret). the average distance between the two tryptophans (residues 158 and 161) and the fluorescently labeled cysteine 190 was 2.16 nm, which closely matched the distance predicted in computer simulations, 2.2 nm. the simulation results were able to explain two previous experimental observations: (i) amino-acid sequences of all ... | 2009 | 19589636 |
| protease-resistant core form of bacillus thuringiensis cry1ie: monomeric and oligomeric forms in solution. | cry1ie is encoded by cry1ie, a gene that is silent in bacillus thuringiensis strains but can be over-expressed in escherichia coli. a protease-resistant core form of cry1ie with a molecular weight of approx. 55 kda was found among the products of trypsin digestion. the oligomer and monomer of the protease-resistant core form were purified separately. the oligomer fraction contained a small quantity of dimer and a large amount of aggregates larger than tetramers. the 50% lethal concentrations (lc ... | 2009 | 19590825 |
| crystal structure of bacillus thuringiensis cry8ea1: an insecticidal toxin toxic to underground pests, the larvae of holotrichia parallela. | crystal (cry) proteins belong to an insect toxin family encoded and expressed by a variety of bacillus thuringiensis isolates, and are named due to their in vivo auto-crystallization abilities. to kill the infected host insects, protease-activated cry toxins should firstly be recognized by certain membrane receptors on the surface of insect midgut epithelial cells and consequently assemble together as lethal transmembrane pores. here we report the 2.2-a crystal structure of cry8ea1 toxin, a cry ... | 2009 | 19591941 |
| modified bacillus thuringiensis toxins and a hybrid b. thuringiensis strain counter greenhouse-selected resistance in trichoplusia ni. | resistance of greenhouse-selected strains of the cabbage looper, trichoplusia ni, to bacillus thuringiensis subsp. kurstaki was countered by a hybrid strain of b. thuringiensis and genetically modified toxins cry1abmod and cry1acmod, which lack helix alpha-1. resistance to cry1abmod and cry1acmod was >100-fold less than resistance to native toxins cry1ab and cry1ac. | 2009 | 19592525 |
| trichogramma (hymenoptera: trichogrammatidae) ecology in a tropical bt transgenic cotton cropping system: sampling to improve seasonal pest impact estimates in the ord river irrigation area, australia. | trichogramma westwood (hymenoptera: trichogrammatidae) cause high mortality rates in the potentially resistant pest species, helicoverpa armigera (hübner) (lepidoptera: noctuidae), and are considered integral to the resistance management plan for bacillus thuringiensis transgenic cotton, gossypium hirsutum l., production in the ord river irrigation area (oria), western australia. measured as percentage of parasitism, trichogramma activity seems highly variable over time; yet, it contributes sign ... | 2009 | 19610415 |
| cry2ab tolerance response of helicoverpa armigera (lepidoptera: noctuidae) populations from crylac cotton planting region. | helicoverpa armigera (hübner) (lepidoptera: noctuidae) is an important lepidopteran pest of cotton, gossypium hirsutum l., in asia. transgenic cotton expressing the cry1ac gene from bacillus thuringiensis (bt) has been widely planted for control of this pest. for managing the potential risk from resistance evolution in this pest, a new transgenic bt cotton containing cry1ac and cry2ab genes (gene pyramided strategy) was designed as a successor of cry1ac cotton. this article reports on levels of ... | 2009 | 19610441 |
| effects of pink bollworm resistance to bacillus thuringiensis on phenoloxidase activity and susceptibility to entomopathogenic nematodes. | widespread planting of crops genetically engineered to produce insecticidal toxins from the bacterium bacillus thuringiensis (bt) imposes selection on many key agricultural pests to evolve resistance to bt. fitness costs can slow the evolution of bt resistance. we examined effects of entomopathogenic nematodes on fitness costs of bt resistance in the pink bollworm, pectinophora gossypiella (saunders) (lepidoptera: gelechiidae), a major pest of cotton, gossypium hirsutum l., in the southwestern u ... | 2009 | 19610442 |
| quantification of cry1ac and cry1f bacillus thuringiensis insecticidal proteins in selected transgenic cotton plant tissue types. | quantitative enzyme-linked immunosorbent assays were used to characterize the geographical (locations) and temporal (through 6 wk) expression of crylac, from bacillus thuringiensis variety kurstaki, and cry1f, from b. thuringiensis variety aizawai, in transgenic cotton, gossypium hirsutum l., plant structures. terminal leaves, squares (flower buds), flowers, bolls (fruit), and mature leaves located five and eight nodes below the terminal apex were sampled during weeks 2, 4, and 6 after the initi ... | 2009 | 19610451 |
| supplemental control of lepidopterous pests on bt transgenic sweet corn with biologically-based spray treatments. | biologically-based spray treatments, including nucleopolyhedroviruses, neem, and spinosad, were evaluated as supplemental controls for the fall armyworm, spodoptera frugiperda (j. e. smith), and corn earworm, helicoverpa zea (boddie) (lepidoptera: noctuidae), on transgenic sweet corn, zea mays (l.) (poales: poaceae), expressing a cry1ab toxin from bacillus thuringiensis berliner (bacillales: bacillaceae) (bt). overall, transgenic corn supported lower densities of both pests than did nontransgeni ... | 2009 | 19611255 |
| novel pink bollworm resistance to the bt toxin cry 1ac: effects on mating, oviposition, larval development and survival. | bt cotton plants are genetically engineered to produce insecticidal toxins from the bacillus thuringiensis (bt) berliner (bacillales: bacillaceae) bacterium and target key lepidopteran pests. in all previous strains of pink bollworm, pectinophora gossypiella (saunders) (lepidoptera: gelechiidae) selected in the laboratory for resistance to insecticidal cry1ac toxin using an artificial diet containing the toxin, resistance to cry1ac and to bt cotton is linked to three cadherin alleles (r1, r2, an ... | 2009 | 19613847 |
| concurrent degradation of dimethyl phthalate (dmp) during production of bacillus thuringiensis based biopesticides. | bacillus thuringiensis var. kurstaki (btk) predominantly used as a microbial insecticide was tested for concomitant degradation of dimethyl phthalate (dmp). different concentrations of dmp, 100, 200, 500, 1000 and 2000 mg/l were initially spiked in tryptic soya broth medium. a control of tryptic soya broth without dmp was also included. the experiments were carried out for 48 h at 30 degrees c and 250 rpm and growth, enzyme and biocontrol assay was evaluated. dmp concentration until 500 mg/l did ... | 2009 | 19615820 |
| a three-domain kazal-type serine proteinase inhibitor exhibiting domain inhibitory and bacteriostatic activities from freshwater crayfish procambarus clarkii. | in crustaceans, kazal-type serine proteinase inhibitors in hemolymph are believed to function as regulators of the host-defense reactions or inhibitors against proteinases from microorganisms. in this study, we report a kazal-type serine proteinase inhibitor, named hcpcspi1, from freshwater crayfish (procambarus clarkii). we found that hcpcspi1 is composed of a putative signal peptide, an rgd motif, and three tandem kazal-type domains with the domain p1 residues l, l and e, respectively. mainly, ... | 2009 | 19616577 |
| the small acid soluble proteins (sasp alpha and sasp beta) of bacillus weihenstephanensis and bacillus mycoides group 2 are the most distinct among the bacillus cereus group. | the bacillus cereus group includes bacillus anthracis, b. cereus, bacillus thuringiensis, bacillus mycoides and bacillus weihenstephanensis. the small acid soluble spore protein (sasp) beta has been previously demonstrated to be among the biomarkers differentiating b. anthracis and b. cereus; sasp beta of b. cereus most commonly exhibits one or two amino acid substitutions when compared to b. anthracis. sasp alpha is conserved in sequence among these two species. neither sasp alpha nor beta for ... | 2009 | 19616612 |
| [genetic transformation of bt gene into sorghum (sorghum bicolor l.) mediated by agrobacterium tumefaciens]. | sorghum (sorghum bicolor l.) was one of the most important crops in the world next to wheat, rice, maize, soybean and barley. using the callus derived from immature inflorescence as the recipients, we efficiently transformed sorghum varieties 115, ics21b and 5-27 with the insecticidal bacillus thuringiensis (bt) cry1ab gene carried in the t-dna of binary vectors which contained hygromycin resistance gene and gus gene via agrobacterium tumefaciens. after gradient selection with hygromycin, a tota ... | 2009 | 19621584 |
| [characterization of insecticidal crystal protein cry gene of bacillus thuringiensis from soil of sichuan basin and cloning of novel holotype cry gene]. | in order to systematically investigate the cry gene resources from bacillus thuringiensis (bt) in different ecological regions in sichuan basin and further clone novel cry genes. | 2009 | 19623955 |
| coleopteran-specific and putative novel cry genes in iranian native bacillus thuringiensis collection. | the characterization of the strains containing coleopteran-specific and also putative novel cry genes in iranian native bacillus thuringiensis collection is presented. characterization was based on pcr analysis using 31 general and specific primers for cry1b, cry1i, cry3a, cry3b, cry3c, cry7a, cry8a, cry8b, cry8c, cry14, cry18, cry26, cry28, cry34 and cry35 genes, protein band patterns as well as their insecticidal activity on xanthogaleruca luteola mull. larvae. forty six isolates (65.7%) conta ... | 2009 | 19631215 |
| a caenorhabditis elegans glycolipid-binding galectin functions in host defense against bacterial infection. | galectins are a family of beta-galactoside-binding proteins that are widely found among animal species and that regulate diverse biological phenomena. to study the biological function of glycolipid-binding galectins, we purified recombinant caenorhabditis elegans galectins (lec-1-11) and studied their binding to c. elegans glycolipids. we found that lec-8 binds to glycolipids in c. elegans through carbohydrate recognition. it has been reported that cry5b-producing bacillus thuringiensis strains ... | 2009 | 19635802 |
| cry1 genes from bacillus thuringiensis: specificity determination and implications for primer design. | some pest management programs employ pcr to identify cry1 genes from bacillus thuringiensis to predict bacterial toxicity towards different insect pests. however, due to changes on the mode of action of the cry proteins, new primers had to be designed to detect the new genes. therefore, an 'in-silico' study of genetic sequences from five cry1 subclasses was carried out and characterized by molecular tools. the design of new primers allows for more precise selection of b. thuringiensis isolates, ... | 2009 | 19636520 |
| susceptibility of culex pipiens (diptera: culicidae) field populations in cyprus to conventional organic insecticides, bacillus thuringiensis subsp. israelensis, and methoprene. | culex pipiens pipiens l. populations on cyprus were sampled over a 6-yr period from 2002 to 2008 to evaluate the status of insecticide resistance toward the insecticides temephos, chlorpyrifos, and permethrin and to study susceptibility levels toward the recently introduced bacterial insecticide bacillus thuringiensis subsp. israelensis de barjac and the juvenile hormone analog, methoprene. susceptibility to the three conventional chemical insecticides varied between different collections, with ... | 2009 | 19645293 |
| current procedures of the integrated urban vector-mosquito control as an example in cotonou (benin, west africa) and wrocław area (poland). | current strategy of integrated vector management (ivm) comprises the general approach of environmentally friendly control measures. with regard to mosquitoes it includes first of all application of microbial insecticides based on bacillus thuringiensis israelensis (bti) and b. sphaericus (bs) delta-endotoxins as well as the reduction of breeding habitats and natural enemy augmentation. it can be achieved thorough implementation of the interdisciplinary program, i. e., understanding of mosquito v ... | 2009 | 20209805 |
| cloning, expression and characterisation of a promising mosquitocidal gene. | a new mosquitocidal gene, cyt1aa6, was isolated and cloned from the novel bacillus thuringiensis strain llp29, previously isolated from the phylloplane of magnolia denudata. nucleotide sequence analysis of cyt1aa6 indicated that the open reading frame consisted of 750 base pairs, encoding 249 amino acid sequences with a calculated molecular weight of 27.3681 kda and a pi value of 4.77. an homological comparison revealed that the cyt1aa6 amino acid sequence was 99% identical with those of known c ... | 2009 | 20112806 |
| efficacy of bacillus thuringiensis var. kurstaki in the control of two mosquito species (anopheles stephensi and culex quinquefasciatus). | bioinsecticide bacillus thuringiensis var. kurstaki (btk) was used for controlling the mosquito species (anopheles stephensi and culex quinquefasciatus) which gave a significant (p<0.05) mortality in both species. the higher concentration of btk was highly effective compared to the control ones. the controlling effect was dose and time dependent. among the studied mosquitoes the c. quinquefasciatus (lc5 0.154%) was more susceptible than a. stephensi (lc50 0.372%) towards the bioinsecticide btk. | 2009 | 20120473 |
| field-evolved insect resistance to bt crops: definition, theory, and data. | transgenic crops producing bacillus thuringiensis (bt) toxins for insect pest control have been successful, but their efficacy is reduced when pests evolve resistance. here we review the definition of field-evolved resistance, the relationship between resistance and field control problems, the theory underlying strategies for delaying resistance, and resistance monitoring methods. we also analyze resistance monitoring data from five continents reported in 41 studies that evaluate responses of fi ... | 2009 | 20069826 |
| european corn borer (lepidoptera: crambidae) infestation level and plant growth stage on whole-plant corn yield grown for silage in virginia. | field experiments were conducted in 2004 and 2005 to determine the effect of different levels of hand-infested third instar european corn borer, ostrinia nubilalis (hiibner) (lepidoptera: crambidae), on whole-plant yield and plant growth stage in corn, zea mays l., grown for silage. in 2004 and 2005, european corn borer infestation level had a significant negative impact on whole-plant yield (grams of dry matter per plant) with increasing infestation; however, whole-plant yield was not significa ... | 2009 | 20069843 |
| assessing the susceptibility of cruciferous lepidoptera to cry1ba2 and cry1ca4 for future transgenic cruciferous vegetables. | advances in transgenic plants expressing bacillus thuringiensis (bt) insecticidal gene(s) offer a promising alternative to traditional insecticides for control of lepidopteran pests on important cruciferous vegetable crops such as cabbage and cauliflower. a public-private partnership, the collaboration on insect management for brassicas in asia and africa (cimbaa), was formed in 2005 with the goal of developing dual-gene bt cauliflower and cabbage, initially for india, to replace the use of broa ... | 2009 | 20069851 |
| susceptibility of helicoverpa armigera (lepidoptera: noctuidae) to cry1ac and cry2ab2 insecticidal proteins in four countries of the west african cotton belt. | transgenic cotton, gossypium hirsutum l., producing cry1ac and cry2ab2 insecticidal proteins from bacillus thuringiensis (bt) was first planted in burkina faso (west africa) in 2008. here, we provide the first baseline data on susceptibility of helicoverpa armigera (hübner) (lepidoptera: noctuidae) populations collected in west africa (benin, cameroon, nigeria, and chad) to cry1ac and cry2ab2 toxins incorporated separately or in combination in a semisynthetic diet. for populations collected in 2 ... | 2009 | 20069861 |
| presence and significance of bacillus thuringiensis cry proteins associated with the andean weevil premnotrypes vorax (coleoptera: curculionidae). | the andean weevil premnotrypes vorax represents an important cause of damage to colombian potato crops. due to the impact of this plague on the economy of the country, we searched for new alternatives for its biological control, based on the entomopathogenic bacteria bacillus thuringiensis. a total of 300 b. thuringiensis strains obtained from potato plantations infested with p. vorax were analyzed through crystal morphology, sds-page, pcr and bioassays. we used site-directed mutagenesis to modi ... | 2009 | 20073348 |
| cry-bt identifier: a biological database for pcr detection of cry genes present in transgenic plants. | we describe the development of a user friendly tool that would assist in the retrieval of information relating to cry genes in transgenic crops. the tool also helps in detection of transformed cry genes from bacillus thuringiensis present in transgenic plants by providing suitable designed primers for pcr identification of these genes. the tool designed based on relational database model enables easy retrieval of information from the database with simple user queries. the tool also enables users ... | 2009 | 20461155 |
| evaluation of community-based strategies for aedes aegypti control inside houses. | dengue viruses transmitted principally by the urban mosquito aedes aegypti, cause one of the major public health problems confronting tropical cities. insecticide spraying has been the mainstay of mosquito control; however, its continuous use has selected for resistance. other important methods of control involve community participation. | 2009 | 20128353 |
| [bt toxic protein expression in insect-resistant transgenic corns and its transfer to and accumulation in ostrinia furnacalis]. | taking the insect-resistant transgenic corn varieties g03-2396 and g03-2739 and the conventional corn variety suyu 16 as test materials, a bioassay in laboratory was conducted to test their resistance against ostrinia furnacalis. the bt toxin expression in different tissues of the two transgenic corns, the ingestion of bt toxin by the 3rd and 5th instar of o. furnacalis, and the bt toxin amount in feces of o. furnacalis larvae fed with bt corns were analyzed by using enzyme-linked-immunosorbent- ... | 2009 | 20136015 |
| binding affinity and larvicidal activity of a novel vegetative insecticidal protein vip3v. | bacillus thuringiensis (bt) is a well-known entomo-pathogen. strains of bt. that are toxic to a variety of insects belonging to various orders such as lepidoptera, diptera and coleoptra have been identified, their larvicidal proteins isolated, characterized and used extensively in agriculture for protecting the economically important crops against these pests. recently a novel group of vegetative insecticidal genes, vip3s and vip3v coding for 789-amino acid (88.5 kda) protein in bacillus thuring ... | 2009 | 20237448 |
| isolation and characterization of bacterial endophytes of chelidonium majus l. | the aim of this study was to isolate and identify endophytic bacteria from stems of chelidonium majus l. (greater celandine) and to evaluate their antifungal properties. in total, 34 bacterial endophyte strains were isolated. the fungistatic effects of these bacteria on the growth of five moulds (alternaria alternata, chaetonium sp., paecilomyces variotti, byssochlamys fulva, aureobasidium pullulans) and one species of black yeast (exophiala mesophila) were tested. the majority of the bacterial ... | 2009 | 20380146 |
| translocation and insecticidal activity of bacillus thuringiensis living inside of plants. | the major biological pesticide for the control of insect infestations of crops, bacillus thuringiensis was found to be present naturally within cotton plants from fields that had never been treated with commercial formulations of this bacterium. the ability of b. thuringiensis to colonize plants as an endophyte was further established by the introduction of a strain marked by production of green fluorescent protein (gfp). after inoculation of this preparation close to the roots of cotton and cab ... | 2009 | 21255282 |
| induction of natural competence in bacillus cereus atcc14579. | natural competence is the ability of certain microbes to take up exogenous dna from the environment and integrate it in their genome. competence development has been described for a variety of bacteria, but has so far not been shown to occur in bacillus cereus. however, orthologues of most proteins involved in natural dna uptake in bacillus subtilis could be identified in b. cereus. here, we report that b. cereus atcc14579 can become naturally competent. when expressing the b. subtilis comk prot ... | 2008 | 21261842 |
| molecular markers to determine the ecological fate of bacillus thuringiensis ssp. kurstaki. | a set of dna markers was developed that successfully identifies bacillus thuringiensis ssp. kurstaki (btk) when screened against other bacillus species and subspecies. these subspecies-specific primer sets allowed detection and characterization of btk within an environmental background that contained many bacillus species. because btk is used as an active ingredient in many commercial formulations, yet is not naturally widely distributed in north america or europe, these markers will prove usefu ... | 2008 | 21585997 |
| bacillus thuringiensis improved isolation methodology from soil samples. | bacillus thuringiensis is a sporulating bacterium, which produces parasporal inclusions toxic to insects. widely used methodologies to isolate bt from soil consist of a thermal shock treatment followed by selective germination of spores. the results presented here suggest that a preliminary 5 h dry-heat treatment largely enhance the selectivity of these procedures. | 2008 | 18619500 |
| the residual occurrences of bacillus thuringiensis biopesticides in food and beverages. | in 2006, 54 pasteurized full fat milk samples, 40 ice-cream samples, and two green-tea beverage samples were analyzed and a total of 19 bacillus thuringiensis-like strains were isolated, nine from seven pasteurized milks, one from an ice-cream with peach pulp and juice, and nine from two green-tea beverages. these strains were classified as b. thuringiensis, contained the cry1a gene and produced crystal inclusions during sporulation. all strains were characterized by a serotyping test, sds-page, ... | 2008 | 18620771 |
| mechanism of the quorum-quenching lactonase (aiia) from bacillus thuringiensis. 1. product-bound structures. | enzymes capable of hydrolyzing n-acyl- l-homoserine lactones (ahls) used in some bacterial quorum-sensing pathways are of considerable interest for their ability to block undesirable phenotypes. most known ahl hydrolases that catalyze ring opening (ahl lactonases) are members of the metallo-beta-lactamase enzyme superfamily and rely on a dinuclear zinc site for catalysis and stability. here we report the three-dimensional structures of three product complexes formed with the ahl lactonase from b ... | 2008 | 18627129 |
| mechanism of the quorum-quenching lactonase (aiia) from bacillus thuringiensis. 2. substrate modeling and active site mutations. | the n-acyl- l-homoserine lactone hydrolases (ahl lactonases) have attracted considerable attention because of their ability to quench ahl-mediated quorum-sensing pathways in gram-negative bacteria and because of their relation to other enzymes in the metallo-beta-lactamase superfamily. to elucidate the detailed catalytic mechanism of ahl lactonase, mutations are made on residues that presumably contribute to substrate binding and catalysis. steady-state kinetic studies are carried out on both th ... | 2008 | 18627130 |
| potential effects of oilseed rape expressing oryzacystatin-1 (oc-1) and of purified insecticidal proteins on larvae of the solitary bee osmia bicornis. | despite their importance as pollinators in crops and wild plants, solitary bees have not previously been included in non-target testing of insect-resistant transgenic crop plants. larvae of many solitary bees feed almost exclusively on pollen and thus could be highly exposed to transgene products expressed in the pollen. the potential effects of pollen from oilseed rape expressing the cysteine protease inhibitor oryzacystatin-1 (oc-1) were investigated on larvae of the solitary bee osmia bicorni ... | 2008 | 18628826 |
| inheritance of cry1f resistance in laboratory-selected european corn borer and its survival on transgenic corn expressing the cry1f toxin. | a major assumption of the high-dose/refuge strategy proposed for insect resistance management strategies for transgenic crop plants that express toxins from bacillus thuringiensis is that resistance traits that evolve in pest species will be recessive. the inheritance of cry1f resistance and larval survival on commercially available cry1f corn hybrids were determined in a laboratory-selected strain of european corn borer, ostrinia nubilalis (hübner), displaying more than 3000-fold resistance to ... | 2008 | 18631419 |
| all domains of cry1a toxins insert into insect brush border membranes. | a critical step in understanding the mode of action of insecticidal crystal toxins from bacillus thuringiensis is their partitioning into membranes and, in particular, the insertion of the toxin into insect brush border membranes. the umbrella and penknife models predict that only alpha-helix 5 of domain i along with adjacent helices alpha-4 or alpha-6 insert into the brush border membranes because of their hydrophobic nature. by employing fluorescent-labeled cysteine mutations, we observe that ... | 2008 | 18635544 |
| unusually high frequency of genes encoding vegetative insecticidal proteins in an australian bacillus thuringiensis collection. | of 188 australian bacillus thuringiensis strains screened for genes encoding soluble insecticidal proteins by polymerase chain reaction/restriction-length fragment polymorphism (rflp) analysis, 87% showed the presence of such genes. although 135 isolates (72%) produced an rflp pattern identical to that expected for vip3a genes, 29 isolates possessed a novel vip-like gene. the novel vip-like gene was cloned from b. thuringiensis isolate c81, and sequence analysis demonstrated that it was 94% iden ... | 2008 | 18592309 |