| fumonisin b(1) and implications in nursery swine productivity: a quantitative exposure assessment. | this study estimated the long-term exposure of fumonisin b(1) (fb(1)) in nursery swine diets and associated toxicological adverse effects on negative productivity potential using quantitative exposure assessment. fumonisin b(1) is a mycotoxin produced by fusarium verticillioides and fusarium proliferatum and is a common biological contaminant of corn (zea mays l.) and other grains. acute effects from fb(1) exposures are well recognized and managed in the swine industry, but practices to limit pr ... | 2010 | 20622179 |
| integration of a recombinant chitinase into bacillus thuringiensis parasporal insecticidal crystal. | chitinases have been successfully used in combination with bacillus thuringiensis delta-endotoxins forming crystals in order to enhance their insecticidal activities. in this context, we opted for promoting the chitinase integration into these crystals. thus, we engineered, for the first time, a fusion protein (cdf) consisting of the chitinase chi255 and the carboxy-terminal half of cry1ac, both from b. thuringiensis subsp. kurstaki. the constructed transcriptional fusion (chi255δsp-ctcry1ac) wa ... | 2011 | 20625731 |
| characterization of a novel bacillus thuringiensis phenotype possessing multiple appendages attached to a parasporal body. | bacillus thuringiensis is a bacterium best known for its production of crystal-like bodies comprised of one or more cry-proteins, which can be toxic to insects, nematodes or cancer cells. although strains of b. thuringiensis have occasionally been observed with filamentous appendages attached to their spores, appendages in association with their parasporal bodies are extremely rare. herein we report the characterization of bt1-88, a bacterial strain isolated from the caribbean that produces a sp ... | 2011 | 20640854 |
| cyt toxin expression reveals an inverse regulation of insect and plant virulence factors of dickeya dadantii. | the plant pathogenic bacteria dickeya dadantii is also a pathogen of the pea aphid acyrthosiphon pisum. the genome of the bacteria contains four cyt genes, encoding homologues of bacillus thuringiensis cyt toxins, which are involved in its pathogenicity to insects. we show here that these genes are transcribed as an operon, and we determined the conditions necessary for their expression. their expression is induced at high temperature and at an osmolarity equivalent to that found in the plant ph ... | 2010 | 20649641 |
| the t box regulatory element controlling expression of the class i lysyl-trna synthetase of bacillus cereus strain 14579 is functional and can be partially induced by reduced charging of asparaginyl-trnaasn. | lysyl-trna synthetase (lysrs) is unique within the aminoacyl-trna synthetase family in that both class i (lysrs1) and class ii (lysrs2) enzymes exist. lysrs1 enzymes are found in archaebacteria and some eubacteria while all other organisms have lysrs2 enzymes. all sequenced strains of bacillus cereus (except ah820) and bacillus thuringiensis however encode both a class i and a class ii lysrs. the lysk gene (encoding lysrs1) of b. cereus strain 14579 has an associated t box element, the first rep ... | 2010 | 20649968 |
| 3'-5' trnahis guanylyltransferase in bacteria. | the identity of the histidine specific transfer rna (trna(his)) is largely determined by a unique guanosine residue at position -1. in eukaryotes and archaea, the trna(his) guanylyltransferase (thg1) catalyzes 3'-5' addition of g to the 5'-terminus of trna(his). here, we show that thg1 also occurs in bacteria. we demonstrate in vitro thg1 activity for recombinant enzymes from the two bacteria bacillus thuringiensis and myxococcus xanthus and provide a closer investigation of several archaeal thg ... | 2010 | 20650272 |
| genetic manipulation in bacillus thuringiensis for strain improvement. | bacillus thuringiensis (bt) has been used as a biopesticide in agriculture, forestry and mosquito control because of its advantages of specific toxicity against target insects, lack of polluting residues and safety to non-target organisms. the insecticidal properties of this bacterium are due to insecticidal proteins produced during sporulation. despite these ecological benefits, the use of bt biopesticides has lagged behind the synthetic chemicals. genetic improvement of bt natural strains, in ... | 2010 | 20652622 |
| intramolecular proteolytic nicking and binding of bacillus thuringiensis cry8da toxin in bbmvs of japanese beetle. | bacillus thuringiensis (bt) cry8d insecticidal proteins are unique among cry8 family proteins in terms of its insecticidal activity against adult scarab beetles, such as japanese beetle (popillia japonica newman). from the sequence homology with other bt cry proteins especially those active against beetles, such as cry3aa whose 3d structure is available, the structure of the cry8d protein has been predicted to be a typical three-domain cry protein type. in addition, the activation process of cry ... | 2010 | 20655921 |
| detection of new cry genes of bacillus thuringiensis by use of a novel pcr primer system. | on the basis of the known cry gene sequences of bacillus thuringiensis, three sets of primers were designed from four conserved blocks found in the delta-endotoxin-coding region. the primer pairs designed amplify the regions between blocks 1 and 5, 2 and 5, and 1 and 4. in silico analyses indicated that 100% of the known three-domain cry gene sequences can be amplified by these sets of primers. to test their ability to amplify known and unknown cry gene sequences, 27 strains from the cinvestav ( ... | 2010 | 20656876 |
| managing resistance to bt crops in a genetically variable insect herbivore, ostrinia nubilalis. | to slow the resistance evolution of the european corn borer (ecb) to cry proteins expressed in transgenic bacillus thuringensis (bt) corn, the united states environmental protection agency (epa) has adopted an insect resistance management (irm) plan that relies on a "high dose/refuge" strategy. however, this irm plan does not consider possible ecological differences between the two ecb pheromone races (e and z). using carbon isotope analysis, we found that unstructured (non-corn) refuges contrib ... | 2010 | 20666246 |
| the role of the electrostatic force in spore adhesion. | electrostatic force is investigated as one of the components of the adhesion force between bacillus thuringiensis (bt) spores and planar surfaces. the surface potentials of a bt spore and a mica surface are experimentally obtained using a combined atomic force microscopy (afm)-scanning surface potential microscopy technique. on the basis of experimental information, the surface charge density of the spores is estimated at 0.03 microc/cm(2) at 20% relative humidity and decreases with increasing h ... | 2010 | 20666490 |
| a cry1ac toxin variant generated by directed evolution has enhanced toxicity against lepidopteran insects. | cry1ac insecticidal crystal proteins produced by bacillus thuringiensis (bt) have become an important natural biological agent for the control of lepidopteran insects. in this study, a cry1ac toxin gene from bacillus thuringiensis 4.0718 was modified by using error-prone pcr, staggered extension process (step) shuffling combined with red/et homologous recombination to investigate the insecticidal activity of delta-endotoxin cry1ac. a cry1ac toxin variant (designated as t524n) screened by insect ... | 2011 | 20669019 |
| effects of infection with nosema pyrausta on survival and development of offspring of laboratory selected bt-resistant and bt-susceptible european corn borers. | infection with nosema pyrausta paillot lengthens developmental period of bt-susceptible ostrinia nubilalis (hübner) to a similar extent as feeding on cry1ab-incorporated diet in cry1ab-resistant o. nubilalis, and these two factors combined lengthen developmental period further than either alone. resistant o. nubilalis mating with infected susceptible, or infected resistant partners would produce partially- and fully-resistant offspring, respectively, infected with n. pyrausta. to investigate the ... | 2010 | 20673768 |
| mosquito fauna and perspectives for integrated control of urban vector-mosquito populations in southern benin (west africa). | this study aims at an integrated vector management (ivm) concept of implementing biological control agents against vector mosquito larvae as a cost-effective and scalable control strategy. in the first step, the mosquito species composition fauna of southern benin was studied using standard entomological procedures in natural and man-made habitats. altogether, 24 species belonging to 6 genera of mosquitoes aedes, anopheles, culex, mansonia, uranotaenia, ficalbia were recorded. five species, cx. ... | 2010 | 20684480 |
| molecular characterization and rna interference of three midgut aminopeptidase n isozymes from bacillus thuringiensis-susceptible and -resistant strains of sugarcane borer, diatraea saccharalis. | aminopeptidase n (apn) proteins located at the midgut epithelium of some lepidopteran species have been implicated as receptors for insecticidal proteins from bacillus thuringiensis. cdnas of three apn isoforms, dsapn1, dsapn2, and dsapn3, from cry1ab-susceptible (cry1ab-ss) and -resistant (cry1ab-rr) strains of the sugarcane borer, diatraea saccharalis (f.) (lepidoptera: crambidae), were identified and sequenced using reverse transcriptase polymerase chain reaction (rt-pcr) and 5' rapid amplifi ... | 2010 | 20685334 |
| analytical particle measurements in an optical microflume. | in this work, microscopic particles in a fluid flow are manipulated using forces generated by a high power laser beam. the resulting manipulations on the particles are imaged using a microscope lens connected to a ccd camera. differential forces on particles of varying physical and chemical composition have been measured. the goal is to measure the optical forces on a diverse range of particles and catalog the associated chemical and physical differences to understand which properties and mechan ... | 2010 | 20685420 |
| [heterogeneous expression of chitinase gene from bcillus licheniformis my75 and the characterization of expressed chimy]. | to heterogeneously express the chitinase gene of bacillus licheniformis strain my75 in e. coli, and to characterize the recombinant chitinase chimy. | 2010 | 20687339 |
| [comparison of midgut bacterial community between bt-resistant and sensitive helicoverpa armigera]. | to investigate the midgut bacterial community of sensitive and resistant helicoverpa armigera for the emergence of resistance to bacillus thuringiensis. | 2010 | 20687351 |
| pore formation by cry toxins. | bacillus thuringiensis (bt) bacteria produce insecticidal cry and cyt proteins used in the biological control of different insect pests. in this review, we will focus on the 3d-cry toxins that represent the biggest group of cry proteins and also on cyt toxins. the 3d-cry toxins are pore-forming toxins that induce cell death by forming ionic pores into the membrane of the midgut epithelial cells in their target insect. the initial steps in the mode of action include ingestion of the protoxin, act ... | 2010 | 20687486 |
| decaplex and real-time pcr based detection of mon531 and mon15985 bt cotton events. | the genetically modified (gm) bt crops expressing delta-endotoxins from bacillus thuringiensis provide protection against a wide range of lepidopteron insect pests throughout the growing season of the plant. bt cotton is the only commercialized crop in india that is planted on an area of 7.6 million hectares. with the increase in development and commercialization of transgenic crops, it is necessary to develop appropriate qualitative and quantitative methods for detection of different transgenic ... | 2010 | 20687600 |
| activation of the latent plcr regulon in bacillus anthracis. | many genes in bacillus cereus and bacillus thuringiensis are under the control of the transcriptional regulator plcr and its regulatory peptide, papr. in bacillus anthracis, the causative agent of anthrax, plcr is inactivated by truncation, and consequently genes having plcr binding sites are expressed at very low levels when compared with b. cereus. we found that activation of the plcr regulon in b. anthracis by expression of a plcr-papr fusion protein does not alter sporulation in strains cont ... | 2010 | 20688829 |
| protection against naegleria fowleri infection in mice immunized with cry1ac plus amoebic lysates is dependent on the stat6 th2 response. | we previously reported that intranasal administration of cry1ac protoxin alone or in combination with amoebic lysates increases protection against naegleria fowleri meningoencephalitis in mice. those results suggested that both antibody responses and innate immune mechanisms may be participating in the protective effects observed. the present study was aimed to investigate whether the stat6-induced th2 immune response is essential for the resistance to n. fowleri infection, conferred by immuniza ... | 2010 | 20691018 |
| residue 544 in domain iii of the bacillus thuringiensis cry1ac toxin is involved in protein structure stability. | a unique residue w544 in the beta18-beta19 loop of the bacillus thuringiensis cry1ac toxin has been implicated in its toxicity. in this study, the effects of mutations at this residue on protein stability during protease treatment, uv irradiation, and preservation were examined. residue 544 of cry1ac was involved in maintaining structural stability, and substitution of a polar group at this position was unfavorable to protein stability. one mutant, w544f, produced larger crystals and was more st ... | 2010 | 20694575 |
| genetic stability in two commercialized transgenic lines (mon810). | | 2010 | 20697396 |
| possible role of plant allelochemical in clearance of bacteria from the gut of spruce budworm, choristoneura fumiferana. | field results, using bacillus thuringiensis delta-endotoxin in controlling spruce budworms, choristoneura fumiferana, are far less satisfactory than those from the laboratoriesthe role of septicemia has also been shown to be important in mortality. however its relationship with insect diet has not been studied. insect gut juice from spruce budworm fed on balsam foliage inhibited bacterial growth. such activity has not been observed in the gut juice from insects fed on artificial diet. moreover, ... | 2010 | 20700395 |
| quantification of toxins in a cry1ac + cpti cotton cultivar and its potential effects on the honey bee apis mellifera l. | transgenic cry1ac + cpti cotton (ccri41) is increasingly planted throughout china. however, negative effects of this cultivar on the honey bee apis mellifera l., the most important pollinator for cultivated ecosystem, remained poorly investigated. the objective of our study was to evaluate the potential side effects of transgenic cry1ac + cpti pollen from cotton on young adult honey bees a. mellifera l. two points emphasized the significance of our study: (1) a higher expression level of insecti ... | 2010 | 20700762 |
| expression of bt-cry3a in transgenic populus alba × p. glandulosa and its effects on target and non-target pests and the arthropod community. | during the growing seasons of 2006-2008, feeding tests and field studies were conducted in beijing, china, to investigate the effects of transgenic bacillus thuringiensis (bt) poplar (bga-5) expressing the cry3a protein (0.0264-0.0326% of the total soluble protein) on target and non-target pests and the arthropod community. the effects of bga-5 on the target pest plagiodera versicolora (coleoptera, chrysomelidae) and a non-target pest clostera anachoreta (lepidoptera, notodontidae), were assesse ... | 2011 | 20703808 |
| [effects of transgenic bt crops on non-target soil animals]. | transgenic bt crops are widely planted around the world. with the quick development and extension of genetically modified crops, it is needed to make a deep study on the effects of bt crops on soil ecosystem. this paper reviewed the research progress on the effects of transgenic bt crops on the population dynamics and community structure of soil animals, e.g., earthworm, nematode, springtail, mite, and beetle, etc. the development history of bt crops was introduced, the passway the bt protein co ... | 2010 | 20707123 |
| generation of marker-free bt transgenic indica rice and evaluation of its yellow stem borer resistance. | we report on generation of marker-free (‘clean dna’) transgenic rice (oryza sativa), carrying minimal gene-expression-cassettes of the genes of interest, and evaluation of its resistance to yellow stem borer scirpophaga incertulas (lepidoptera: pyralidae). the transgenic indica rice harbours a translational fusion of 2 different bacillus thuringiensis (bt) genes, namely cry1b-1aa, driven by the green-tissue-specific phosphoenol pyruvate carboxylase (pepc) promoter. mature seed-derive ... | 2010 | 20720299 |
| histopathology and the lethal effect of cry proteins and strains of bacillus thuringiensis berliner in spodoptera frugiperda j.e. smith caterpillars (lepidoptera, noctuidae). | among the phytophagous insects which attack crops, the fall armyworm, spodoptera frugiperda (j.e. smith, 1797) (lepidoptera, noctuidae) is particularly harmful in the initial growth phase of rice plants. as a potential means of controlling this pest, and considering that the entomopathogen bacillus thuringiensis berliner demonstrates toxicity due to synthesis of the cry protein, the present study was undertaken to evaluate this toxic effect of b. thuringiensis thuringiensis 407 (ph 408) and b. t ... | 2010 | 20730357 |
| wide-scale application of bti/bs biolarvicide in different aquatic habitat types in urban and peri-urban malindi, kenya. | larval control is a major component in mosquito control programs. this study evaluated the wide-scale application of bti/bs biolarvicide (bacillus thuringiensis var. israelensis [bti] and bacillus sphaericus [bs]) in different aquatic habitats in urban and peri-urban malindi, kenya. this study was done from june 2006 to december 2007. the urban and peri-urban area of malindi town was mapped and categorized in grid cells of 1 km(2). a total of 16 1-km(2) cells were selected based on presence comm ... | 2011 | 20730445 |
| cyt1aa protein from bacillus thuringiensis (berliner) serovar israelensis is active against the mediterranean fruit fly, ceratitis capitata (wiedemann). | ceratitis capitata (wiedemann) is one of the world's most destructive fruit pests. the aim of this study was to ascertain insecticidal activity of bacillus thuringiensis (berliner) delta-endotoxins to c. capitata. | 2010 | 20730986 |
| characterization of an environmental strain of bacillus thuringiensis from a hot spring in western himalayas. | bacillus anthracis, the etiological agent of anthrax, is responsible for a serious and often fatal disease of mammalian livestock and humans and is an important biological warfare agent. bacillus sp. akg was isolated from a hot spring in western himalayas and species-specific primers targeting gyrb gene identified the strain as b. anthracis within cereus-group. cloning, sequencing, and phylogenetic analysis of the partial gyrb sequence from strain akg indicated a close affiliation with b. anthra ... | 2011 | 20737272 |
| cry genes profiling and the toxicity of isolates of bacillus thuringiensis from soil samples against american bollworm, helicoverpa armigera. | the aim of this study was to search for bacillus thuringiensis (bt) harbouring cry1a gene which could effectively control cotton pest, american bollworm, helicoverpa armigera. | 2010 | 20738439 |
| laboratory toxicity studies demonstrate no adverse effects of cry1ab and cry3bb1 to larvae of adalia bipunctata (coleoptera: coccinellidae): the importance of study design. | scientific studies are frequently used to support policy decisions related to transgenic crops. schmidt et al., arch environ contam toxicol 56:221-228 (2009) recently reported that cry1ab and cry3bb were toxic to larvae of adalia bipunctata in direct feeding studies. this study was quoted, among others, to justify the ban of bt maize (mon 810) in germany. the study has subsequently been criticized because of methodological shortcomings that make it questionable whether the observed effects were ... | 2011 | 20740377 |
| safety assessment of cry1c protein from genetically modified rice according to the national standards of pr china for a new food resource. | the cry1c protein produced in escherichia coli was used for in vitro evaluation and animal studies to support the safety assessment of gm food or feed products containing the cry1c protein. the cry1c protein does not have any sequence homology with known allergens or toxins. although the cry1c protein was heat stable it was rapidly degraded in vitro with simulated gastric or intestinal fluids. it did not cause adverse effects in mice as administered by gavage at a high level dosage of 5 g (cry1c ... | 2010 | 20801181 |
| histopathology and ultrastructure of midgut of alabama argillacea (hübner) (lepidoptera: noctuidae) fed bt-cotton. | the interaction of cry toxins from bacillus thuringiensis in the midgut of some insect larvae determines their efficacies as insecticides, due to the expression and availability of sites of action of the toxin in the midgut. researches point out cases of resistance to cry toxin due to alterations in the binding sites in columnar cell membrane. we analyzed the effects of cry1ac toxin expressed by bt-cotton plants on alabama argillacea midgut morphophysiology clarifying in levels of morphological ... | 2010 | 20804764 |
| synergistic and inhibitory effects of aminopeptidase peptides on bacillus thuringiensis cry11ba toxicity in the mosquito anopheles gambiae. | cry11ba produced by bacillus thuringiensis subsp. jegathesan is an active toxin for larvae of the mosquito anopheles gambiae. a 106-kda aminopeptidase n (apn), called agapn2, was previously identified as a cry11ba receptor in a. gambiae. a 70-kda fragment of agapn2 expressed in escherichia coli binds cry11ba with high affinity (k(d) = 6.4 nm) and inhibits cry11ba activity by 98% in bioassays [zhang et al. (2008) biochemistry 47, 11263-11272]. to identify regions involved in toxicity, we truncate ... | 2010 | 20809561 |
| metal displacement and stoichiometry of protein-metal complexes under native conditions using capillary electrophoresis/mass spectrometry. | increases in the study of protein-metal complexes, as well as in metal displacement in protein-metal complexes under native conditions for optimum catalytic properties in drug research and catalyst design, demands a separation/detection technology that can accurately measure metal displacement and stoichiometry in protein-metal complexes. both nuclear magnetic resonance (nmr) and x-ray diffraction techniques have been used for this purpose; however, these techniques lack sensitivity. electrospra ... | 2010 | 20814979 |
| sub-chronic lung inflammation after airway exposures to bacillus thuringiensis biopesticides in mice. | the aim of the present study was to assess possible health effects of airway exposures to bacillus thuringiensis (bt) based biopesticides in mice. endpoints were lung inflammation evaluated by presence of inflammatory cells in bronchoalveolar lavage fluid (balf), clearance of bacteria from the lung lumen and histological alterations of the lungs. hazard identifications of the biopesticides were carried out using intratracheal (i.t.) instillation, followed by an inhalation study. the two commerci ... | 2010 | 20815884 |
| cotton bollworm resistance to bt transgenic cotton: a case analysis. | cotton bollworm (helicoverpa armigera) is one of the most serious insect pests of cotton. transgenic cotton expressing cry toxins derived from a soil bacterium, bacillus thuringiensis (bt), has been produced to target this pest. bt cotton has been widely planted around the world, and this has resulted in efficient control of bollworm populations with reduced use of synthetic insecticides. however, evolution of resistance by this pest threatens the continued success of bt cotton. to date, no fiel ... | 2010 | 20821292 |
| a decade of bt cotton in chinese fields: assessing the direct effects and indirect externalities of bt cotton adoption in china. | the objective of this study is to examine whether or not the gains from reduced spraying for bollworms are being sustained more than one decade after the initial adoption in 2007. based on farm-level data collected by the authors in 1999-2007 in 16 villages from 4 provinces, this study shows that insecticides applied for controlling bollworms have declined. this analysis supports chinese policy makers' decision to not require refuges of non-bt cotton fields. it also suggests that past studies ma ... | 2010 | 20821297 |
| cry1ab toxin production of mon 810 transgenic maize. | levels of cry1ab toxin were detected in genetically modified maize of genetic event mon 810 against near isogenic maize as negative control by two commercial immunoassays. the immunoassays were characterized for their cross-reactivity (cr) between cry1ab protoxin and activated toxin, and were compared with each other for toxin detection in a reference plant sample. cry1ab toxin levels, corrected for active toxin content using the cr values obtained, were monitored in maize dk-440 bty through the ... | 2010 | 20821434 |
| influence of selected antibiotics on the response of black fly (simulium vittatum) larvae to insecticidal proteins produced by bacillus thuringiensis subsp. israelensis. | a controlled current toxicity test (cctt) was developed to evaluate the response of black fly (simulium vittatum) larvae to insecticidal proteins following exposure to various antibiotics. the bacterium, bacillus thuringiensis subsp. israelensis (bti), produces proteins that are toxic to nemotoceran diptera, such as black flies and mosquitoes, when ingested. these insecticidal crystalline proteins (icps) are highly efficacious in controlling black flies; however, speculation has arisen regarding ... | 2010 | 20821641 |
| a multiplex real-time pcr for identifying and differentiating b. anthracis virulent types. | bacillus anthracis is closely related to the endospore forming bacteria bacillus cereus and bacillus thuringiensis. for accurate detection of the life threatening pathogen b. anthracis, it is essential to distinguish between these three species. here we present a novel multiplex real-time pcr for simultaneous specific identification of b. anthracis and discrimination of different b. anthracis virulence types. specific b. anthracis markers were selected by whole genome comparison and different se ... | 2011 | 20826037 |
| development and validation of a real-time quantitative pcr assay for rapid identification of bacillus anthracis in environmental samples. | a real-time polymerase chain reaction (pcr) assay was developed for rapid identification of bacillus anthracis in environmental samples. these samples often harbor bacillus cereus bacteria closely related to b. anthracis, which may hinder its specific identification by resulting in false positive signals. the assay consists of two duplex real-time pcr: the first pcr allows amplification of a sequence specific of the b. cereus group (b. anthracis, b. cereus, bacillus thuringiensis, bacillus weihe ... | 2010 | 20827474 |
| a quadruple-enterotoxin-deficient mutant of bacillus thuringiensis remains insecticidal. | bacillus thuringiensis is the leading biopesticide used to control insect pests worldwide. although they have a long record of safe use, under certain conditions commercial strains of b. thuringiensis have the ability to produce numerous putative enterotoxins that have been associated with food poisoning attributed to bacillus cereus. therefore, we designed a strategy to delete the genes encoding these toxins. b. thuringiensis strain vbts 2477 contained genes encoding nhe, cytk-2 and three homol ... | 2010 | 20829288 |
| incipient resistance of helicoverpa punctigera to the cry2ab bt toxin in bollgard ii cotton. | combinations of dissimilar insecticidal proteins ("pyramids") within transgenic plants are predicted to delay the evolution of pest resistance for significantly longer than crops expressing a single transgene. field-evolved resistance to bacillus thuringiensis (bt) transgenic crops has been reported for first generation, single-toxin varieties and the cry1 class of proteins. our five year data set shows a significant exponential increase in the frequency of alleles conferring cry2ab resistance i ... | 2010 | 20830203 |
| binding of bacillus thuringiensis cry1a toxins with brush border membrane vesicles of maize stem borer (chilo partellus swinhoe). | maize stem borer (chilo partellus) is a major insect pest of maize and sorghum in asia and africa. bacillus thuringiensis (bt) δ-endotoxins have been found effective against c. partellus, both in diet-overlay assay and in transgenic plants. gene stacking as one of the resistance management strategies in bt maize requires an understanding of receptor sharing and binding affinity of δ-endotoxins. in the present study, binding affinity of three fluorescein isothiocyanate labeled cry1a toxins showed ... | 2011 | 20831871 |
| interaction of bacillus thuringiensis vegetative insecticidal protein with ribosomal s2 protein triggers larvicidal activity in spodoptera frugiperda. | vegetative insecticidal protein (vip3a) is synthesized as an extracellular insecticidal toxin by certain strains of bacillus thuringiensis. vip3a is active against several lepidopteran pests of crops. polyphagous pest, spodoptera frugiperda, and its cell line sf21 are sensitive for lyses to vip3a. screening of cdna library prepared from sf21 cells through yeast two-hybrid system with vip3a as bait identified ribosomal protein s2 as a toxicity-mediating interacting partner protein. the vip3a-ribo ... | 2010 | 20833785 |
| optimization of spray drying process for bacillus thuringiensis fermented wastewater and wastewater sludge. | response surface methodology was used to optimize spray drying process for producing biopesticide powders of bacillus thuringiensis by using fermented broth of starch industry wastewater and wastewater sludge. analysis of variance was carried out using number of viable spores in the powder as dependent variable. the determination coefficients of models were 92 and 94% for fermented broth of starch industry wastewater and wastewater sludge, respectively. under the optimal conditions of the operat ... | 2011 | 20835715 |
| bacillus thuringiensis protein cry6b (bgsc id 4d8) is toxic to larvae of hypera postica. | insecticidal proteins produced by strains of bacillus thuringenesis are specific toward target pests. one of the bt proteins, cry 1ac has been used successfully for controlling crop predation by polyphagous pests helicoverpa armigera. structurally, bt proteins consist of three domains; domain i and iii are fairly homologous in various bt proteins while domain ii is hypervariable. the hypervariable domain ii is believed to be responsible for specificity toward target pest. successful deployment o ... | 2011 | 20835830 |
| non-target organism effects tests on vip3a and their application to the ecological risk assessment for cultivation of mir162 maize. | transgenic crops producing insecticidal proteins from bacillus thuringiensis (bt) provide economic, environmental and health benefits by maintaining or increasing crop yields with fewer applications of insecticide. to sustain these benefits, it is important to delay the evolution of insect resistance to the proteins, and to ensure that the proteins do not harm non-target organisms, particularly those that may control secondary pests that would otherwise flourish because of reduced insecticide ap ... | 2011 | 20839052 |
| structural characteristics and phylogenetic analysis of the mitochondrial genome of the sugarcane borer, diatraea saccharalis (lepidoptera: crambidae). | the sugarcane borer, diatraea saccharalis (f.), is an economically important pest of several major crops in north and south america. there is great concern over potential resistance development to the valuable transgenic bacillus thuringiensis corn. cost-effective monitoring methods, especially regarding molecular markers that could detect early changes in resistance allele frequency in field populations of d. saccharalis, are needed. this article reports the complete mitochondrial genome sequen ... | 2011 | 20849253 |
| mosquito biolarvicide production by sequential fermentation with dual strains of bacillus thuringiensis subsp. israelensis and bacillus sphaericus using sewage sludge. | this study demonstrated the bioconversion of sewage sludge into a composite biolarvicide for mosquito control based on sequential fermentation with dual strains of bacillus thuringiensis subsp. israelensis (bti) and bacillus sphaericus (bs). results showed that sewage sludge was a suitable fermentation substrate for supporting growth, sporulation and mosquitocidal proteins synthesis by bti and bs. through sequential fermentation with dual strains, a 10-l bench-scale fermentor was capable of prod ... | 2011 | 20855197 |
| discovery and characterization of field resistance to bt maize: spodoptera frugiperda (lepidoptera: noctuidae) in puerto rico. | transgenic maize, zea mays l., event tc1507 produces the cry1f protein to provide protection from feeding by several important lepidopteran pests, including spodoptera frugiperda (j.e. smith) (lepidoptera: noctuidae). reports of reduced field performance against this species in puerto rico were investigated, and laboratory bioassays showed that s. frugiperda collected from the affected area exhibited lower sensitivity to the cry1f protein compared with typical colonies from other regions. the re ... | 2010 | 20857709 |
| potential impact of differential production of the cry2ab and cry1ac proteins in transgenic cotton in response to cold stress. | transgenic bollgard ii cotton, gossypium hirsutum l., expresses cry1ac and cry2ab proteins that provide control of lepidopteran larvae, including helicoverpa and heliothis species (lepidoptera: noctuidae) worldwide. experiments conducted at katherine, northern territory, australia evaluated the impact of night minimum temperatures on cry1ac and cry2ab protein levels in bollgard ii cotton. in both 2003 and 2004, potted plants were either grown outside continuously or protected from cold in a glas ... | 2010 | 20857729 |
| fitness costs of cry1ab resistance in a field-derived strain of ostrinia nubilalis (lepidoptera: crambidae). | the study of fitness costs associated with resistance to toxins from bacillus thuringiensis berliner (bt) in ostrinia nubilalis (hübner) (lepidoptera: crambidae) is important for understanding resistance evolution and for evaluating resistance management practices that prevent or mitigate resistance to transgenic corn, zea mays l. resistant individuals identified from a field collection in kandiyohi, mn, were used to generate a cry1ab-resistant strain. we used susceptible and resistant strains w ... | 2010 | 20857752 |
| transgenic rice plants expressing a fused protein of cry1ab/vip3h has resistance to rice stem borers under laboratory and field conditions. | six transgenic rice, oryza sativa l., lines (g6h1, g6h2, g6h3, g6h4, g6h5, and g6h6) expressing a fused cry1ab/vip3h protein, were evaluated for resistance against the asiatic rice borer, chilo suppressalis (walker) (lepidoptera: crambidae), and the stem borer sesamia inferens (walker) (lepidoptera: noctuidae) in the laboratory and field. the bioassay results indicated that the mortality of asiatic rice borer and s. inferens neonate larvae on six transgenic lines from seedling to filling stage w ... | 2010 | 20857760 |
| toxicity of seven bacillus thuringiensis cry proteins against cylas puncticollis and cylas brunneus (coleoptera: brentidae) using a novel artificial diet. | "sweetpotato weevils" cylas puncticollis (boheman) and cylas brunneus f. (coleoptera: brentidae) are the most important biological threat to sweetpotato, ipomoea batatas l. (lam), productivity in sub-saharan africa. sweetpotato weevil control is difficult due to their cryptic feeding behavior. expression of cylas-active bacillus thuringiensis (bt) cry proteins in sweetpotato could provide an effective control strategy. unfortunately, bt cry proteins with relatively high toxicity against cylas sp ... | 2010 | 20857765 |
| constitutive activation of the midgut response to bacillus thuringiensis in bt-resistant spodoptera exigua. | bacillus thuringiensis is the most effective microbial control agent for controlling numerous species from different insect orders. the main threat for the long term use of b. thuringiensis in pest control is the ability of insects to develop resistance. thus, the identification of insect genes involved in conferring resistance is of paramount importance. a colony of spodoptera exigua (lepidoptera: noctuidae) was selected for 15 years in the laboratory for resistance to xentari™, a b. thuringien ... | 2010 | 20862260 |
| short-term evaluation in growing rats of diet containing bacillus thuringiensis cry1ia12 entomotoxin: nutritional responses and some safety aspects. | the cry1ia12 entomotoxin from a brazilian bacillus thuringiensis strain is currently being expressed in cotton cultivars to confer resistance to insect-pests. the present study aimed to assess the effects of a diet containing cry1ia12 protein on growing rats. a test diet containing egg white and cry1ia12 (0.1% of total protein) as a protein source was offered to rats for ten days. in addition, an acute toxicity bioassay was performed in rats with a single oral dose of the entomotoxin (12 mg/anim ... | 2010 | 20862341 |
| genome-wide screening reveals the genetic determinants of an antibiotic insecticide in bacillus thuringiensis. | thuringiensin is a thermostable secondary metabolite in bacillus thuringiensis and has insecticidal activity against a wide range of insects. until now, the regulatory mechanisms and genetic determinants involved in thuringiensin production have remained unclear. here, we successfully used heterologous expression-guided screening in an escherichia coli-bacillus thuringiensis shuttle bacterial artificial chromosome library, to clone the intact thuringiensin synthesis (thu) cluster. then the thu c ... | 2010 | 20864531 |
| insect-resistant genetically modified rice in china: from research to commercialization. | from the first insect-resistant genetically modified (irgm) rice transformation in 1989 in china to october 2009 when the chinese ministry of agriculture issued biosafety certificates for commercial production of two cry1ab/ac bacillus thuringiensis (bt) lines, china made a great leap forward from irgm rice basic research to potential commercialization of the world's first irgm rice. research has been conducted on developing irgm rice, assessing its environmental and food safety impacts, and eva ... | 2011 | 20868281 |
| use of an innovative t-tube maze assay and the proboscis extension response assay to assess sublethal effects of gm products and pesticides on learning capacity of the honey bee apis mellifera l. | transgenic cry1ac+cpti cotton (ccri41) is a promising cotton cultivar throughout china but side effects and especially sublethal effects of this transgenic cultivar on beneficial insects remain poorly studied. more specifically potential sublethal effects on behavioural traits of the honey bee apis mellifera l. have not been formally assessed despite the importance of honey bees for pollination. the goal of our study was to assess potential effects of ccri41 cotton pollen on visual and olfactory ... | 2010 | 20872243 |
| occurrence of maize detritus and a transgenic insecticidal protein (cry1ab) within the stream network of an agricultural landscape. | widespread planting of maize throughout the agricultural midwest may result in detritus entering adjacent stream ecosystems, and 63% of the 2009 us maize crop was genetically modified to express insecticidal cry proteins derived from bacillus thuringiensis. six months after harvest, we conducted a synoptic survey of 217 stream sites in indiana to determine the extent of maize detritus and presence of cry1ab protein in the stream network. we found that 86% of stream sites contained maize leaves, ... | 2010 | 20876106 |
| the role of β20-β21 loop structure in insecticidal activity of cry1ac toxin from bacillus thuringiensis. | the β20-β21 loop is a unique structure in the domain iii of bacillus thuringiensis cry proteins. in this study, the role of β20-β21 loop on insecticidal activity of cry1ac toxin was investigated. 10 residues in β20-β21 loop were substituted with alanine using pcr-based site-directed mutagenesis. all mutants were capable of producing diamond-shaped crystal and expressing a protein sized 130 kda. the mutants s581a and i585a enhanced toxicity against helicoverpa armigera larvae dramatically, while ... | 2010 | 20878161 |
| monitoring the commercial cultivation of bt maize in europe--conclusions and recommendations for future monitoring practice. | genetically modified (gm) maize expressing the insecticidal protein cry1ab from bacillus thuringiensis (bt maize) is the only gm crop planted commercially in the european union (eu). cultivation in accordance with directive 2001/18/ec demands post-market environmental monitoring (pmem) to ensure the detection and prevention of adverse effects on the environment possibly deriving from commercial cultivation. based on a seminar organized in berlin, germany, in april 2008 by the eu-funded biosafene ... | 2010 | 20883660 |
| participation of valine 171 in alpha-helix 5 of bacillus thuringiensis cry1ab delta-endotoxin in translocation of toxin into lymantria dispar midgut membranes. | the cry1ab δ-endotoxin v171c mutant protein exhibits a 25-fold increase in toxicity against lymantria dispar, which correlates with a faster rate of partitioning into the midgut membrane and slightly decreased protein stability. this is an insect-specific mechanism; similar results were not observed in manduca sexta, another cry1ab δ-endotoxin-susceptible insect. | 2010 | 20889788 |
| homology modeling of cry10aa toxin from b. thuringiensis israelensis and b. thuringiensis subsp. ldc-9. | a three dimensional model was developed for cry10aa protein sequence of b. thuringiensis ldc-9 and b. thuringiensis israelensis that has not been solved empirically by x-ray crystallography or nmr. homology modeling was employed for the structure prediction using cry2aa as template protein, a high-resolution x-ray crystallography structure. the model predicted for the b. thuringiensis ldc-9 cry10aa protein reveals a partial n-terminal domain only due to its partial sequence of 104 amino acids. b ... | 2010 | 20919752 |
| plant science. communal benefits of transgenic corn. | | 2010 | 20929767 |
| areawide suppression of european corn borer with bt maize reaps savings to non-bt maize growers. | transgenic maize engineered to express insecticidal proteins from the bacterium bacillus thuringiensis (bt) has become widely adopted in u.s. agriculture. in 2009, bt maize was planted on more than 22.2 million hectares, constituting 63% of the u.s. crop. using statistical analysis of per capita growth rate estimates, we found that areawide suppression of the primary pest ostrinia nubilalis (european corn borer) is associated with bt maize use. cumulative benefits over 14 years are an estimated ... | 2010 | 20929774 |
| stability of the mon 810 transgene in maize. | we analysed the dna variability of the transgene insert and its flanking regions in maize mon 810 commercial varieties. southern analysis demonstrates that breeding, since the initial transformation event more than 10 years ago, has not resulted in any rearrangements. a detailed analysis on the dna variability at the nucleotide level, using dna mismatch endonuclease assays, showed the lack of polymorphisms in the transgene insert. we conclude that the mutation rate of the transgene is not signif ... | 2010 | 20936423 |
| recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants. | this paper provides recommendations on experimental design for early-tier laboratory studies used in risk assessments to evaluate potential adverse impacts of arthropod-resistant genetically engineered (ge) plants on non-target arthropods (ntas). while we rely heavily on the currently used proteins from bacillus thuringiensis (bt) in this discussion, the concepts apply to other arthropod-active proteins. a risk may exist if the newly acquired trait of the ge plant has adverse effects on ntas whe ... | 2010 | 20938806 |
| inheritance patterns, dominance, stability, and allelism of insecticide resistance and cross-resistance in two colonies of culex quinquefasciatus (diptera: culicidae) selected with cry toxins from bacillus thuringiensis subsp, israelensis. | mendelian crosses were used to analyze the patterns of inheritance of cry-toxin resistance in two colonies of culex quinquefasciatus say larvae resistant to bacterial toxins produced by bacillus thuringiensis subsp. israelensis de barjac. resistance levels exceeded 1000-fold at 95% lethal concentration of the cryllaa-resistant colony (cq11a). f1 offspring of reciprocal crosses to a susceptible colony revealed autosomal inheritance and offspring were intermediate in resistance to the susceptible ... | 2010 | 20939376 |
| impacts of bt transgenic cotton on integrated pest management. | transgenic cotton that produced one or more insecticidal proteins of bacillus thuringiensis (bt) was planted on over 15 million hectares in 11 countries in 2009 and has contributed to a reduction of over 140 million kilograms of insecticide active ingredient between 1996 and 2008. as a highly selective form of host plant resistance, bt cotton effectively controls a number of key lepidopteran pests and has become a cornerstone in overall integrated pest management (ipm). bt cotton has led to larg ... | 2010 | 20942488 |
| acute oral, pulmonary and intravenous toxicity/pathogenicity testing of a new formulation of bacillus thuringiensis var israelensis sh-14 in rats. | during the last decades, efforts are being made to develop microbial insecticides as biological control agents. bacillus thuringiensis has been one of the most consistent and significant biopesticides for using on crops as an insecticidal spray. the aim of this study was to assess and to compare the pathogenicity of a new formulation of b.thuringiensis var israelensis sh-14 in rats through oral, intranasal and intravenous single dosing. through 21 days after administration, clinical examinations ... | 2010 | 20946931 |
| enhanced yield performance of bt rice under target-insect attacks: implications for field insect management. | the rapid development of transgenic biotechnology has greatly promoted the breeding of genetically engineered (ge) rice in china, and many ge rice lines are in the pipeline for commercialization. to understand field performances of ge rice, key agronomic traits of two insect-resistant bt rice lines that have been granted biosafety certificates for commercial production in china were evaluated together with their nontransgenic counterparts under environmental conditions with significant differenc ... | 2010 | 20949317 |
| natural refuge crops, buildup of resistance, and zero-refuge strategy for bt cotton in china. | in the context of genetically modified crops expressing the bacillus thuringiensis (bt) toxin, a 'refuge' refers to a crop of the same or a related species that is planted nearby to enable growth and reproduction of the target pest without the selection pressure imposed by the bt toxin. the goal of this study is to discuss the role of natural refuge crops in slowing down the buildup of resistance of cotton bollworm (cbw), and to evaluate china's no-refuge policy for bt cotton. we describe in det ... | 2010 | 20953946 |
| characterization of vegetative insecticidal protein vip genes of bacillus thuringiensis from sichuan basin in china. | vegetative insecticidal proteins (vip), the second generation of insecticides, are produced during the vegetative growth stage of bacillus thuringiensis (bt). to perform a systematic study of vip genes in bt strains from different ecological regions of sichuan basin, 1,789 soil samples were collected from this basin, which is situated in the western region of china. the basin has a complicated geomorphology and contains mountains, forests, highlands, hursts, and plains. a total of 2,134 bt strai ... | 2010 | 20963416 |
| study of the bacillus thuringiensis vip3aa16 histopathological effects and determination of its putative binding proteins in the midgut of spodoptera littoralis. | the bacterium bacillus thuringiensis produces, at the vegetative stage of its growth, vip3a proteins with activity against a broad spectrum of lepidopteran insects. the egyptian cotton leaf worm (spodoptera littoralis) is an important agricultural pest that is susceptible to the vip3aa16 protein of bacillus thuringiensis kurstaki strain bupm95. the midgut histopathology of vip3aa fed larvae showed vacuolization of the cytoplasm, brush border membrane destruction, vesicle formation in the apical ... | 2010 | 20965198 |
| mega assemblages of oligomeric aerolysin-like toxins stabilized by toxin-associating membrane proteins. | most β pore-forming toxins need to be oligomerized via receptors in order to form membrane pores. though oligomerizing toxins frequently form sds-resistant oligomers, it was questionable whether sds-resistant oligomers reflected native functional toxin complexes. in order to elucidate the essence of the cytocidal assemblages, oligomers of aerolysin-like toxins, aerolysin, parasporin-2 and epsilon toxin, were examined with or without sds. on blue native page, each toxin, which had been solubilize ... | 2010 | 20971989 |
| rapid topology probing using fluorescence spectroscopy in planar lipid bilayer: the pore-forming mechanism of the toxin cry1aa of bacillus thuringiensis. | pore-forming toxins, many of which are pathogenic to humans, are highly dynamic proteins that adopt a different conformation in aqueous solution than in the lipid environment of the host membrane. consequently, their crystal structures obtained in aqueous environment do not reflect the active conformation in the membrane, making it difficult to deduce the molecular determinants responsible for pore formation. to obtain structural information directly in the membrane, we introduce a fluorescence ... | 2010 | 20974771 |
| filament structure of bacterial tubulin homologue tubz. | low copy number plasmids often depend on accurate partitioning systems for their continued survival. generally, such systems consist of a centromere-like region of dna, a dna-binding adaptor, and a polymerizing cytomotive filament. together these components drive newly replicated plasmids to opposite ends of the dividing cell. the bacillus thuringiensis plasmid pbtoxis relies on a filament of the tubulin/ftsz-like protein tubz for its segregation. by combining crystallography and electron micros ... | 2010 | 20974911 |
| persistence of bacillus thuringiensis israelensis (bti) in the environment induces resistance to multiple bti toxins in mosquitoes. | background: the simultaneous production of six different toxins by bacillus thuringiensis israelensis (bti) is thought to delay the evolution of resistance in treated mosquito populations. recent studies have shown that bti can persist and proliferate in the environment, thereby imposing continuous selective pressure on mosquito populations, raising concerns about the long-term effectiveness of this bioinsecticide. in order to evaluate the effect of bti persistence on the evolution of resistance ... | 2010 | 20981724 |
| expression of δ-endotoxin cry1ec from an inducible promoter confers insect protection in peanut (arachis hypogaea l.) plants. | spodoptera litura (f.) is a polyphagous foliage insect and a major pest on peanut (arachis hypogaea l.). constitutive expression of δ-endotoxin cry1ec gives protection against s. litura, as reported earlier. in this study, insect bites and salicylic acid induced high-level expression of cry1ec was achieved in peanut. in order to achieve this, the expression of pathogenesis responsive promoter pr-1a was enhanced by placing it downstream of the camv35s promoter in the pcambia 1300 backbone. the re ... | 2011 | 20981728 |
| heterologous overexpression, purification, and in vitro characterization of ahl lactonases. | quorum-quenching enzymes are useful as biochemical tools and possible therapeutic proteins. one of the best-characterized families of these catalysts is the n-acyl-l-homoserine lactone (ahl) lactonases, which rely on a dinuclear metal ion active site to hydrolytically cleave the autoinducer's lactone bond and inactivate signaling. a detailed understanding of how this enzyme works can help in the design of more selective and efficient reagents. to facilitate these studies, we describe a methodolo ... | 2011 | 21031319 |
| field efficacy of granular formulations of bacillus thuringiensis israelensis--strain am65-52 against floodwater mosquitoes in poland and germany. | this paper presents results of studies evaluating the efficacy of various granular formulations of vectobac (bacillus thuringiensis israelensis de barjac [bti] h-14 strain am65-52) against immature mosquitoes in 2 distinct habitats in poland and germany. meadows intermittently flooded with sewage water in the city of wroclaw, poland, provide ideal habitats for immature stages of aedes caspius, ae. vexans, and culex pipiens pipiens. helicopter applications of vectobac g and vectobac tp sand granu ... | 2010 | 21033056 |
| adsorption of transgenic insecticidal cry1ab protein to sio2. 2. patch-controlled electrostatic attraction. | adsorption governs the fate of cry proteins from genetically modified bt crops in soils. the effect of ionic strength (i) on the adsorption of cry1ab (isoelectric point iep(cry1ab) ≈ 6) to negatively charged quartz (sio(2)) and positively charged poly-l-lysine (pll) was investigated at ph 5 to 8, using quartz crystal microbalance with dissipation monitoring and optical waveguide lightmode spectroscopy. cry1ab adsorbed via positively and negatively charged surface patches to sio(2) and pll, respe ... | 2010 | 21033744 |
| adsorption of transgenic insecticidal cry1ab protein to sio2. 1. forces driving adsorption. | genetically modified bt crops express insecticidal cry proteins (bt toxins) that may enter agricultural soils. a mechanistic understanding of cry protein adsorption to soils is critical for risk assessment, as this process governs cry protein fate and bioavailability. we used quartz crystal microbalance and optical waveguide lightmode spectroscopy to elucidate the driving forces of the adsorption of monomeric cry1ab to negatively charged quartz (sio(2)) and positively charged poly-l-lysine (pll) ... | 2010 | 21033745 |
| bt-toxin uptake by the non-target herbivore, myzus persicae (hemiptera: aphididae), feeding on transgenic oilseed rape in laboratory conditions. | the potential non-target effects of genetically modified crops are some of the more debated topics within applied biotechnologies in agriculture and environmental risk assessment. the objective of the present research was to study the potential bt-toxin uptake by the non-target herbivore myzus persicae sulzer (hemiptera: aphididae) feeding on transgenic oilseed rape plants (brassica napus cv. 'westar' lines gt 2-4) expressing the cry1ac endotoxin. a specific aim was to replicate our previous exp ... | 2010 | 21034523 |
| effects of transgenic bt cotton on overwintering characteristics and survival of helicoverpa armigera. | the effects of transgenic bt cotton on the overwintering generation of the cotton bollworm, helicoverpa armigera (hübner) (lepidoptera: noctuidae), are unknown. we hypothesized that a bt cotton diet may adversely affect fitness of this generation and examined fresh weight, lipids, glycogens, low-molecular-weight sugars and scps (supercooling points) of pupae, as well as survival of larvae, diapausing pupae and adult emergence in comparison with controls. field and laboratory experiments showed t ... | 2010 | 21034745 |
| cadherin, alkaline phosphatase, and aminopeptidase n as receptors of cry11ba toxin from bacillus thuringiensis subsp. jegathesan in aedes aegypti. | cry11ba is one of the most toxic proteins to mosquito larvae produced by bacillus thuringiensis. it binds aedes aegypti brush border membrane vesicles (bbmv) with high affinity, showing an apparent dissociation constant (k(d)) of 8.2 nm. we previously reported that an anticadherin antibody competes with cry11ba binding to bbmv, suggesting a possible role of cadherin as a toxin receptor. here we provide evidence of specific cadherin repeat regions involved in this interaction. using cadherin frag ... | 2010 | 21037295 |
| identification of the minimal active fragment of the cry1ah toxin. | cry1ah1, a novel holo-type gene cloned from bacillus thuringiensis strain bt-8, encoded a protein exhibiting strong insecticidal activity against lepidopteran insects. to identify the minimal active fragment of the cry1ah toxin, 9 pairs of primers were designed to generate different pcr products. seven pcr products were amplified by different primers using the cry1ah1 gene as a template and cloned into a pet-21b vector. these positive clones were separately transformed into escherichia coli. ins ... | 2010 | 21046197 |
| transgenic sugarcane plants expressing high levels of modified cry1ac provide effective control against stem borers in field trials. | to improve transgene expression level, we synthesized a truncated insecticidal gene m-cry1ac by increasing its gc content from 37.4 to 54.8%, based on the codon usage pattern of sugarcane genes, and transferred it into two sugarcane cultivars (roc16 and yt79-177) by microprojectile bombardment. the integration sites and expression pattern of the transgene were determined, respectively, by southern, northern and western blot analyses. the transgenic sugarcane lines produced up to 50 ng cry1ac pro ... | 2010 | 21046242 |
| genetic diversity of cry gene sequences of bacillus thuringiensis strains analyzed by denaturing gradient gel electrophoresis. | pcr has been widely used to identify cry-type genes, to determine their distribution, to detect new such genes and to predict insecticidal activities. we describe here a molecular approach to analyze the genetic diversity of b. thuringiensis cry-like genes based on denaturing gradient gel electrophoresis (dgge). this analysis demonstrated that different b. thuringiensis isolates can be distinguished according to its pcr-dgge profile of cry-like genes. identification of the resolvable dna fragmen ... | 2010 | 21046400 |
| control of pine processionary moth, thaumetopoea pityocampa with bacillus thuringiensis in antalya, turkey. | taumetopoea pityocampa (den. and schiff) is one of the most common defoliator insects found in turkey. although several methods have been used in attempting to control this major forest pest up to now but the problem still remains largely unsolved in turkey. there is an urgent need to control and minimize the damages caused by these defoliating caterpillars. therefore, we planned and applied field treatments using by foray 76b and vbc 60074 to put forward to the efficiency of these bioinsecticid ... | 2010 | 21047011 |
| responses of stream macroinvertebrates to bt maize leaf detritus. | in the midwestern united states, maize detritus enters streams draining agricultural land. genetically modified bt maize is commonly planted along streams and can possibly affect benthic macroinvertebrates, specifically members of the order trichoptera, which are closely related to target species of some bt toxins and are important detritivores in streams. the significance of inputs of bt maize to aquatic systems has only recently been recognized, and assessments of potential nontarget impacts o ... | 2010 | 21049882 |
| trna 5'-end repair activities of trnahis guanylyltransferase (thg1)-like proteins from bacteria and archaea. | the trna(his) guanylyltransferase (thg1) family comprises a set of unique 3'-5' nucleotide addition enzymes found ubiquitously in eukaryotes, where they function in the critical g(-1) addition reaction required for trna(his) maturation. however, in most bacteria and archaea, g(-1) is genomically encoded; thus post-transcriptional addition of g(-1) to trna(his) is not necessarily required. the presence of highly conserved thg1-like proteins (tlps) in more than 40 bacteria and archaea therefore su ... | 2010 | 21051361 |
| survival of betta splendens fish (regan, 1910) in domestic water containers and its effectiveness in controlling aedes aegypti larvae (linnaeus, 1762) in northeast brazil. | objective: in northeast brazil, large domestic containers used to store water are important breeding sites of aedes aegypti, the main vector of dengue fever. the objective of this study was to estimate the survival of betta splendens (perciformes: osphronemidae) fish in domestic containers in fortaleza (ceará state), as well as its effectiveness in the control of premature a. aegypti stages. methods: the use of b. splendens was compared to bacillus thuringiensis israelensis (bti) in domestic con ... | 2010 | 21054694 |