Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| stability, oviposition attraction, and larvicidal activity of binary toxin from bacillus sphaericus expressed in escherichia coli. | bacillus sphaericus produces a two-chain binary toxin composed of bina (42 kda) and binb (51 kda), which are deposited as parasporal crystals during sporulation. the toxin is highly active against culex larvae and aedes and anopheles mosquitoes, which are the principal vectors for the transmission of malaria, yellow fever, encephalitis, and dengue. the use of b. sphaericus and bacillus thuringiensis in mosquito control programs is limited by their sedimentation in still water. in this study, the ... | 2011 | 22202967 |
| Bacillus thuringiensis Cry3Aa toxin increases the susceptibility of Crioceris quatuordecimpunctata to Beauveria bassiana infection. | The spotted asparagus beetle, Crioceris quatuordecimpunctata (Coleoptera: Chrysomelidae), is one of the most devastating pests of asparagus in China. Sprayed synthetic pesticides have been used to control C. quatuordecimpunctata damage, but they pose problems because of residues and harm to natural enemies. Neither the microbial coleopteran-specific toxin from Bacillus thuringiensistenebrionis, Cry3Aa, nor the fungal pathogen Beauveria bassiana have sufficient activity to effectively control C. ... | 2011 | 22200644 |
| Scanning surface potential microscopy of spore adhesion on surfaces. | The adhesion of spores of Bacillus anthracis - the cause of anthrax and a likely biological threat - to solid surfaces is an important consideration in cleanup after an accidental or deliberate release. However, because of safety concerns, directly studying B. anthracis spores with advanced instrumentation is problematic. As a first step, we are examining the electrostatic potential of Bacillus thuringiensis (Bt), which is a closely related species that is often used as a simulant to study B. an ... | 2011 | 22196463 |
| a pangenomic study of bacillus thuringiensis. | bacillus thuringiensis (b. thuringiensis) is a soil-dwelling gram-positive bacterium and its plasmid-encoded toxins (cry) are commonly used as biological alternatives to pesticides. in a pangenomic study, we sequenced seven b. thuringiensis isolates in both high coverage and base-quality using the next-generation sequencing platform. the b. thuringiensis pangenome was extrapolated to have 4196 core genes and an asymptotic value of 558 unique genes when a new genome is added. compared to the pang ... | 2011 | 22196399 |
| Laboratory and Field Evaluation of Formulated Bacillus thuringiensis var. israelensis as a Feed Additive and Using Topical Applications for Control of Musca domestica (Diptera: Muscidae) Larvae in Caged-Poultry Manure. | Infestations of house flies, Musca domestica L., are a continual problem around poultry establishments. Acute toxicity of two commercial Bacillus thuringiensis variety israelensis (Bti) formulations (water-dispersible granules and bran formulation) was evaluated against larvae in the laboratory and against natural populations of M. domestica larvae in the field applied in feed to chickens and as topical applications in the poultry houses. Bioassay data showed that susceptibility of M. domestica ... | 2011 | 22182611 |
| multi-generation effects of bt rice on anagrus nilaparvatae, a parasitoid of the nontarget pest nilapavarta lugens. | little is known about the potential cumulative long-term effects of transgenic crops on nontarget organisms. in the present laboratory study, the potential cumulative effects of transgenic bacillus thuringiensis (bt) rice on parasitoids in successive generations were observed for an egg parasitoid, anagrus nilaparvatae parasitizing eggs of nilaparvata lugens (stål) (hemiptera: delphacidae) feeding on bt rice. enzyme-linked immunosorbent assay test confirmed that cry1ab insecticidal protein coul ... | 2010 | 22182572 |
| molecular modeling of bt cry1ac (di-dii)-asal (allium sativum lectin)-fusion protein and its interaction with aminopeptidase n (apn) receptor of manduca sexta. | genetic engineering of bacillus thuringiensis (bt) cry proteins has resulted in the synthesis of various novel toxin proteins with enhanced insecticidal activity and specificity towards different insect pests. in this study, a fusion protein consisting of the di-dii domains of cry1ac and garlic lectin (asal) has been designed in silico by replacing the diii domain of cry1ac with asal. the binding interface between the di-dii domains of cry1ac and lectin has been identified using protein-protein ... | 2012 | 22182469 |
| Regulatory considerations surrounding the deployment Of Bt-expressing cowpea In Africa: Report of the deliberations of an expert panel. | Cowpea (Vigna unguiculata spp. unguiculata) is adapted to the drier agro-ecological zones of West Africa where it is a major source of dietary protein and widely used as a fodder crop. Improving the productivity of cowpea can enhance food availability and security in West Africa. Insect predation - predominately from the legume pod borer (Maruca vitrata), flower thrips (Megalurothrips sjostedti) and a complex of pod-sucking bugs (e.g., Clavigralla spp.) - is a major yield-limiting factor in West ... | 2011 | 22179194 |
| characterization of bacillus thuringiensis isolates with potential for control of aedes aegypti (linnaeus, 1762) (diptera: culicidae). | aedes aegypti (linnaeus) is the vector of dengue virus in brazil. bioinsecticides based on bacillus thuringiensis have shown satisfactory results in the control of diptera, due to the production of proteins called cry and cyt. the aim of the present study was to select b. thuringiensis isolates carrying the cry and cyt genes, which are efficient in the control of ae. aegypti. a collection of 27 isolates of b. thuringiensis, derived from various regions in brazil, was evaluated using selective bi ... | 2011 | 22178674 |
| Nanoscale imaging of Bacillus thuringiensis flagella using atomic force microscopy. | Because bacterial flagella play essential roles in various processes (motility, adhesion, host interactions, secretion), studying their expression in relation to function is an important challenge. Here, we use atomic force microscopy (AFM) to gain insight into the nanoscale surface properties of two wild-type and four mutant strains of Bacillus thuringiensis exhibiting various levels of flagellation. We show that, unlike AFM in liquid, AFM in air is a simple and reliable approach to observe the ... | 2011 | 22159046 |
| Molecular characterization of Bacillus thuringiensis isolated from diverse habitats of India. | Bacillus thuringiensis (Bt) strains were isolated from 94 samples from different geographical regions. Novel types of crystalline inclusion bodies were observed from some of the isolates. Crystalline inclusions of bipyramidal, spherical and cuboidal morphology were found produced by most of the isolates. Isolate GS12 showed crystal on one side of spore while isolate GM108 formed crystals on both termini of spore. Isolate GN31 produced large sized bipyramidal crystals. SDS-PAGE analysis of the sp ... | 2011 | 22144134 |
| A novel protein with a fibrinogen-like domain involved in the innate immune response of Marsupenaeus japonicus. | Fibrinogen-related proteins play important roles in innate immunity. We isolated a fibrinogen-related protein gene (MjFREP1) in kuruma shrimp Marsupenaeus japonicus. MjFREP1 encoded a protein of 270 amino acids, including a 223 amino acid fibrinogen-like domain. Quantitative real-time polymerase chain reaction analysis shows that MjFREP1 is mainly expressed in the gills and the expression is significantly upregulated by Vibrio anguillarum, Staphylococcus aureus, or white spot syndrome virus (WSS ... | 2012 | 22142703 |
| the bacterium, lysinibacillus sphaericus, as an insect pathogen. | since the first bacteria with insecticidal activity against mosquito larvae were reported in the 1960s, many have been described, with the most potent being isolates of bacillus thuringiensis or lysinibacillus sphaericus (formerly and best known as bacillus sphaericus). given environmental concerns over the use of broad spectrum synthetic chemical insecticides and the evolution of resistance to these, industry placed emphasis on the development of bacteria as alternative control agents. to date, ... | 2012 | 22137877 |
| characterization of a new highly mosquitocidal isolate of bacillusthuringiensis - an alternative to bti? | the mosquito is a very important vector involved in the worldwide transmission of disease-causing viruses and parasites. controlling the mosquito population remains one of the best means for preventing the serious infectious diseases of malaria, yellow fever, dengue, filariasis and so on and there has been an increasing interest in developing biopesticides as a useful substitute to chemical insecticides. as a result, bacillus thuringiensis subsp. israelensis (bti) has been extensively used due t ... | 2011 | 22137876 |
| the potential of the novel mosquitocidal bacillus thuringiensis strain llp29 for use in practice. | 2011 | 22129420 | |
| [characterization of bacillus thuringiensis sigk disruption mutant and its influence on activation of cry3a promoter]. | to construct and characterize a sigk gene disruption mutant of bacillus thuringiensis and to study influence of sigk gene disruption on the activation of cry3a gene promoter. | 2011 | 22126072 |
| Genetically modified crops and aquatic ecosystems: considerations for environmental risk assessment and non-target organism testing. | Environmental risk assessments (ERA) support regulatory decisions for the commercial cultivation of genetically modified (GM) crops. The ERA for terrestrial agroecosystems is well-developed, whereas guidance for ERA of GM crops in aquatic ecosystems is not as well-defined. The purpose of this document is to demonstrate how comprehensive problem formulation can be used to develop a conceptual model and to identify potential exposure pathways, using Bacillus thuringiensis (Bt) maize as a case stud ... | 2011 | 22120952 |
| comparative proteomic analysis revealed metabolic changes and the translational regulation of cry protein synthesis in bacillus thuringiensis. | b. thuringiensis strain ybt-1520 is highly toxic to some lepidopteran pests and is used to control pests in southern part of china. the aim of this work is to uncover the metabolic changes associated with the icp synthesis. a comparative proteomic analysis on the strain was performed with 2-de and maldi-tof-ms methods with the bacterial culture grown in a modified defined minimal medium. transcriptional expression of some key enzymes for carbohydrate metabolism was also investigated with qpcr. s ... | 2011 | 22119885 |
| transcription profiling of resistance to bti toxins in the mosquito aedes aegypti using next-generation sequencing. | the control of mosquitoes transmitting infectious diseases relies mainly on the use of chemical insecticides. however, resistance to most chemical insecticides threatens mosquito control programs. in this context, the spraying of toxins produced by the bacteria bacillus thuringiensis subsp. israelensis (bti) in larval habitats represents an alternative to chemical insecticides and is now widely used for mosquito control. recent studies suggest that resistance of mosquitoes to bti toxin may occur ... | 2011 | 22115744 |
| [Effects of Bt corn straw insecticidal proteins on enzyme activities of Eisenia fetida]. | Bacillus thuringiensis (Bt) proteins released from Bt corn can enter soil ecosystem via returning straw into field, root exudation, and pollen fluttering-down. In this study, the straws of Bt corn and its near-isogenic non-Bt line were added into soil with an application rate of 5% and 7.5% to breed Eisenia fetida, and the total protein content and the activities of acetylcholine esterase (AchE), glutathione peroxidase (GSH-PX), catalase (CAT), and superoxide dismutase (SOD) in E. fetida were de ... | 2011 | 22097378 |
| bacillus thuringiensis cry2ab is active on anopheles mosquitoes: single d block exchanges reveal critical residues involved in activity. | cry2aa exhibits dual activity to lepidoptera and diptera. cry2ab differs in amino acid sequence from cry2aa by 13% and has shown significant lepidopteran activity, but no mosquitocidal activity. previous studies implicate 23 cry2aa specificity-conferring residues of domain ii, which differ in cry2ab. nine residues are putatively involved in conferring cry2aa dipteran specificity. to explore cry2ab dipteran toxicity, site-directed mutagenesis was employed to exchange cry2ab residues with cry2aa d ... | 2011 | 22092857 |
| the 20-kda chaperone-like protein of bacillus thuringiensis ssp. israelensis enhances yield, crystal size and solubility of cry3a. | aims: to determine whether the 20-kda chaperone-like protein of bacillus thuringiensis ssp. israelensis enhances synthesis, crystallization and solubility of the cry3a coleopteran toxin and whether the crystalline inclusions produced are toxic to neonates of the colorado potato beetle, leptinotarsa decemlineata. methods and results: the cry3a gene was expressed in the 4q7 strain of b. thuringiensis ssp. israelensis in the absence or presence of the 20-kda gene. the 20-kda protein enhanced cry3 ... | 2011 | 22085291 |
| Diagnostic properties of three conventional selective plating media for selection of Bacillus cereus, B. thuringiensis and B. weihenstephanensis. | The aim of this study was to assess the diagnostic properties of the two selective plating media and a chromogenic medium for identification of Bacillus cereus. The 324 isolates were B. cereus (37%), Bacillus weihenstephanensis (45%) or Bacillus thuringiensis (18%), as identified by a new combination of techniques. All isolates were growing on mannitol-egg yolk-polymyxin agar (MYP), and they did not form acid from mannitol. However, a significant lower number of B. thuringiensis isolates did not ... | 2011 | 22083787 |
| differential protection of cry1fa toxin against spodoptera frugiperda larval gut proteases by cadherin orthologs correlates with increased synergism. | the cry proteins produced by bacillus thuringiensis (bt) are the most widely used biopesticides effective against a range of crop pests and disease vectors. like chemical pesticides, development of resistance is the primary threat to the long-term efficacy of bt toxins. recently discovered cadherin-based bt cry synergists showed the potential to augment resistance management by improving efficacy of cry toxins. however, the mode of action of bt cry synergists is thus far unclear. here we elucida ... | 2012 | 22081566 |
| The impact of the Bacillus subtilis SPB1 biosurfactant on the midgut histology of Spodoptera littoralis (Lepidoptera: Noctuidae) and determination of its putative receptor. | SPB1 is a Bacillus subtilis strain producing a lipopeptide biosurfactant. The insecticidal activity of this biosurfactant was evaluated against the Egyptian cotton leaf worm (Spodoptera littoralis). It displayed toxicity with an LC(50) of 251ng/cm(2). The histopathological changes occurred in the larval midgut of S. littoralis treated with B. subtilis SPB1 biosurfactant were vesicle formation in the apical region, cellular vacuolization and destruction of epithelial cells and their boundaries. L ... | 2011 | 22079884 |
| Gene clusters located on two large plasmids determine spore crystal association (SCA) in Bacillus thuringiensis subsp. finitimus strain YBT-020. | Crystals in Bacillus thuringiensis are usually formed in the mother cell compartment during sporulation and are separated from the spores after mother cell lysis. In a few strains, crystals are produced inside the exosporium and are associated with the spores after sporulation. This special phenotype, named 'spore crystal association' (SCA), typically occurs in B. thuringiensis subsp. finitimus. Our aim was to identify genes determining the SCA phenotype in B. thuringiensis subsp. finitimus stra ... | 2011 | 22076131 |
| Plasmid patterns of efficient and inefficient strains of Bacillus thuringiensis against Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). | Bacillus thuringiensis harbors genes encoding Cry proteins found in chromosomes or plasmids of different sizes (4-150 Mb). Although the smaller plasmids are more abundant in B. thuringiensis, their specific function is unknown. As for the megaplasmids, their main recognized function is to harbor cry genes, although the sequencing of some of these plasmids indicates the occurrence of other important genes. This work used a new protocol for practical and rapid extraction of plasmid DNA in order to ... | 2011 | 22068947 |
| Resistance performances of transgenic bt rice lines T(2A)-1 and T1c-19 against Cnaphalocrocis medinalis (Lepidoptera: Pyralidae). | The transgenic Bacillus thuringiensis (Bt) rice, Oryza sativa L., lines T(2A)-1 and T1c-19 expressing Cry2A* and Cry1C* from 'Minhui 63' (MH63) were evaluated for resistance to newly hatched and third-instar larvae of Cnaphalocrocis medinalis (Lepidoptera: Pyralidae), by using detached leaf laboratory bioassays. Both T(2A)-1 and T1c-19 rice showed high C. medinalis resistance; however, the lethal time (LT)50 of larvae fed with T(2A)-1 rice was significantly longer than that of larvae fed with T1 ... | 2011 | 22066204 |
| mortality impact of bt transgenic maize roots expressing ecry3.1ab, mcry3a, and ecry3.1ab plus mcry3a on western corn rootworm larvae in the field. | mortality of the western corn rootworm, diabrotica virgifera virgifera leconte, larvae due to feeding on maize, zea mays l., expressing bacillus thuringiensis berliner (bt) was evaluated in five missouri sites in 2007, 2008, and 2009. specifically, ecry3.1ab (5307), mcry3a (mir604), and ecry3.1ab plus mcry3a proteins relative to survivorship on maize with the same genetic background without these genes (isoline maize) was evaluated. an average of 890.8 +/- 152.3 beetles emerged from isoline plot ... | 2011 | 22066188 |
| cross-pollination of nontransgenic corn ears with transgenic bt corn: efficacy against lepidopteran pests and implications for resistance management. | the efficacy of nontransgenic sweet corn, zea mays l., hybrids cross-pollinated by bacillus thuringiensis (bt) sweet corn hybrids expressing cry1ab toxin was evaluated in both field and laboratory studies in minnesota in 2000. non-bt and bt hybrids (maternal plants) were cross-pollinated with pollen from both non-bt and bt hybrids (paternal plants) to create four crosses. subsequent crosses were evaluated for efficacy in the field against european corn borer, ostrinia nubilalis (hübner), and cor ... | 2011 | 22066174 |
| insecticidal potency of bacterial species bacillus thuringiensis sv2 and serratia nematodiphila sv6 against larvae of mosquito species aedes aegypti, anopheles stephensi, and culex quinquefasciatus. | the tremendous worldwide efforts to isolate novel mosquito larvicidal bacteria with improved efficacy present significant promise to control vector-borne diseases of public health importance. in the present study, two native bacterial isolates, bacillus thuringiensis (bt sv2) and serratia species (sv6) were evaluated for mosquito larvicidal potential against the early fourth instar larvae of aedes aegypti, anopheles stephensi, and culex quinquefasciatus with reference to b. thuringiensis subsp. ... | 2011 | 22065062 |
| Friction and Adhesion Forces of Bacillus thuringiensis Spores on Planar Surfaces in Atmospheric Systems. | The kinetic friction force and the adhesion force of Bacillus thuringiensis spores on planar surfaces in atmospheric systems were studied using atomic force microscopy. The influence of relative humidity (RH) on these forces varied for different surface properties including hydrophobicity, roughness, and surface charge. The friction force of the spore was greater on a rougher surface than on mica, which is atomically flat. As RH increases, the friction force of the spores decreases on mica where ... | 2011 | 22059743 |
| Factors influencing the seasonal abundance of Aedes (Stegomyia) aegypti and the control strategy of dengue and dengue haemorrhagic fever in Thanlyin Township, Yangon City, Myanmar. | From June 2006 to May 2007, mosquito surveys were conducted in Thanlyin Township, Yangon City, Myanmar, to determine factors influencing the abundance of Aedes aegypti (Stegomyia aegypti) during the rainy season. Both the biological and environmental factors were included in this study. Increase in the hatchability of egg, larval survival rate, the shortened larval life-span and increased pupation rates supplemented by rainfall (i.e. continuous flooding of the containers, stimulate the ... | 2011 | 22041749 |
| Construction of Gene Library of 20 kb DNAs from Parasporal Crystal in Bacillus thuringiensis Strain 4.0718: Phylogenetic Analysis and Molecular Docking. | The 20 kb DNAs are associated with crystals in many subspecies of Bacillus thuringiensis. We isolated 20 kb DNAs from crystals of B. thuringiensis strain 4.0718, then constructed a gene library using DNA fragments of Sau3AI partial digestion and pbluescriptIISK(+) vector. We screened out 440 recombinants, yielding a genomic coverage of ten and including 99% sequence of DNA which achieved the required theoretical value to construct the gene library. Through NCBI Blast and homology analysis, the s ... | 2011 | 22038038 |
| Characterization of Type II and III Restriction-Modification Systems from Bacillus cereus Strains ATCC 10987 and ATCC 14579. | The genomes of two Bacillus cereus strains (ATCC 10987 and ATCC 14579) have been sequenced. Here, we report the specificities of type II/III restriction (R) and modification (M) enzymes. Found in the ATCC 10987 strain, BceSI is a restriction endonuclease (REase) with the recognition and cut site CGAAG 24-25/27-28. BceSII is an isoschizomer of AvaII (G/GWCC). BceSIII cleaves at ACGGC 12/14. The BceSIII C terminus resembles the catalytic domains of AlwI, MlyI, and Nt.BstNBI. BceSIV is composed of ... | 2012 | 22037402 |
| toxicity of bacillus thuringiensis cry proteins to helicoverpa armigera (lepidoptera: noctuidae) in south africa. | the susceptibility of one of the most important pests in southern africa, helicoverpa armigera (lepidoptera: noctuidae), to bacillus thuringiensis cry proteins was evaluated by bioassay. cry proteins were produced in escherichia coli bl21 cells that were transformed with plasmids containing one of six cry genes. the toxicity of each cry protein to h. armigera larvae was determined by the diet contamination method for second instar larvae and the droplet feeding method for neonate larvae. for eac ... | 2012 | 22019386 |
| Characterization of Bacillus thuringiensis soil isolates from Cuba, with insecticidal activity against mosquitoes. | Chemical insecticides may be toxic and cause environmental degradation. Consequently, biological control for insects represents an alternative with low ecological impact. In this work, three soil isolates (A21, A51 and C17) from different regions of the Cuban archipelago were identified, characterized and evaluated against Aedes aegypti and Culex quinquefasciatus. The new isolates were compared with reference IPS82 strain and two strains isolated from biolarvicides Bactivec and Bactoculicida, re ... | 2011 | 22017108 |
| antimicrobial potential of egg yolk ovoinhibitor, a multidomain kazal-like inhibitor of chicken egg. | chicken egg ovoinhibitor is a multidomain kazal-type serine protease inhibitor with unknown function. comparison of expression between different tissues indicated that ovoinhibitor is highly expressed in the magnum and liver followed by the uterus, which secrete egg white, egg yolk, and eggshell precursors, respectively. the results also revealed that ovoinhibitor expression is increased in the liver during sexual maturation followed by a subsequent decrease in mature hens. ovoinhibitor was puri ... | 2011 | 22010862 |
| single molecule fluorescence study of the bacillus thuringiensis toxin cry1aa reveals tetramerization. | pore-forming toxins constitute a class of potent virulence factors that attack their host membrane in a two- or three-step mechanism. after binding to the membrane, often aided by specific receptors, they form pores in the membrane. pore formation either unfolds a cytolytic activity in itself or provides a pathway to introduce enzymes into the cells that act upon intracellular proteins. the elucidation of the pore-forming mechanism of many of these toxins represents a major research challenge. a ... | 2011 | 22006922 |
| green synthesis and antimicrobial evaluation of some new trifluoromethyl-substituted hexahydropyrimidines by grinding. | a series of trifluoromethyl-substituted hexahydropyrimidine derivatives were efficiently synthesized in excellent yields via one-pot three-component reaction of aromatic aldehydes, ethyl trifluoroacetoacetate and thiourea(urea) in presence of p-toluenesulfonic acid under solvent-free conditions at room temperature by grinding. the present method does not involve any hazardous organic solvent and has proven to be simple, efficient, environmentally benign and cost-effective compared with the class ... | 2011 | 22000920 |
| [Cloning of a large plasmid pBMB28 in Bacillus thuringiensis]. | Bacillus thuringiensis serovar. finitimus strain YBT-020 is a typical strain with the spore-crystal association (SCA) phenotype. In our previous studies, plasmid curing experiment suggested that native plasmid pBMB28 of strain YBT-020 might contribute to the SCA phenotype. Thus, plasmid pBMB28 was cloned in order to isolate the genes related to SCA on pBMB28. Using shuttle vector pEMB0557, a shuttle genomic bacterial artificial chromosome (BAC) library of B. thuringiensis strain YBT-020 was cons ... | 2011 | 21993289 |
| down regulation of a gene for cadherin, but not alkaline phosphatase, associated with cry1ab resistance in the sugarcane borer diatraea saccharalis. | the sugarcane borer, diatraea saccharalis, is a major target pest of transgenic corn expressing bacillus thuringiensis (bt) proteins (i.e., cry1ab) in south america and the mid-southern region of the united states. evolution of insecticide resistance in such target pests is a major threat to the durability of transgenic bt crops. understanding the pests' resistance mechanisms will facilitate development of effective strategies for delaying or countering resistance. alterations in expression of c ... | 2011 | 21991350 |
| compositional equivalence of insect-protected glyphosate-tolerant soybean mon 87701 × mon 89788 to conventional soybean extends across different world regions and multiple growing seasons. | the soybean product mon 87701 × mon 89788 expresses both the cry1ac gene derived from bacillus thuringiensis and the cp4 epsps (5-enolpyruvylshikimate-3-phosphate synthase) gene derived from agrobacterium sp. strain cp4. each biotechnology-derived trait confers specific benefits of insect resistance and glyphosate tolerance, respectively. the purpose of this study was to compare the composition of seed and forage from this combined-trait product to those of conventional soybean grown in geog ... | 2011 | 21985102 |
| efficacy of genetically modified bt toxins against insects with different genetic mechanisms of resistance. | transgenic crops that produce bacillus thuringiensis (bt) toxins are grown widely for pest control, but insect adaptation can reduce their efficacy. the genetically modified bt toxins cry1abmod and cry1acmod were designed to counter insect resistance to native bt toxins cry1ab and cry1ac. previous results suggested that the modified toxins would be effective only if resistance was linked with mutations in genes encoding toxin-binding cadherin proteins. here we report evidence from five major cro ... | 2011 | 21983521 |
| monalysin, a novel ß-pore-forming toxin from the drosophila pathogen pseudomonas entomophila, contributes to host intestinal damage and lethality. | pseudomonas entomophila is an entomopathogenic bacterium that infects and kills drosophila. p. entomophila pathogenicity is linked to its ability to cause irreversible damages to the drosophila gut, preventing epithelium renewal and repair. here we report the identification of a novel pore-forming toxin (pft), monalysin, which contributes to the virulence of p. entomophila against drosophila. our data show that monalysin requires n-terminal cleavage to become fully active, forms oligomers in vit ... | 2011 | 21980286 |
| occurrence, characterization and insecticidal activity of bacillus thuringiensis strains isolated from argan fields in morocco. | soils collected from five locations in the argan forest (an endemic plant) in morocco were used to form the first collection of bacillus thuringiensis (bt) strains from this area (58 strains). here we found that the argan forest is a major source of bt, as 90.62% of the samples contained bt strains. these strains produced mainly spherical or irregular crystals that in some cases remained adhered to the spore after cell lysis. there was no strain producing bipyramidal crystals, suggesting the abs ... | 2011 | 21970180 |
| an improved system for the surface immobilisation of proteins on bacillus thuringiensis vegetative cells and spores through a new spore cortex-lytic enzyme anchor. | an improved surface-immobilisation system was engineered to target heterologous proteins onto vegetative cells and spores of bacillus thuringiensis plasmid-free recipient strain bmb171. the sporulation-dependent spore cortex-lytic enzyme from b. thuringiensis ybt-1520, scea, was expressed in vegetative cells and used as the surface anchoring motif. green fluorescent protein (gfp) and a bacillus endo-β-1,3-1,4-glucanase (bgls) were used as the fusion partners to test the binding efficiency and th ... | 2011 | 21968393 |
| use of mixed cultures of biocontrol agents to control sheep nematodes. | biological control is a promising non-chemical approach for the control of gastrointestinal nematodes of sheep. use of combinations of biocontrol agents have been reported to be an effective method to increase the efficacy of biological control effects. in this study, combinations of either two bacillus thuringiensis (bt) or clonostachys rosea (c. rosea) isolates and bt+c. rosea isolates were evaluated in vitro in microtitre plates for their biocontrol activity on sheep nematodes. the baermann t ... | 2011 | 21962967 |
| cyt1aa toxin: crystal structure reveals implications for its membrane-perforating function. | during sporulation, bacillus thuringiensis subsp. israelensis produces a mosquito larvicidal protein complex containing several crystalline and cytolytic (cyt) toxins. here, the activated monomeric form of cyt1aa, the most toxic cyt family member, was isolated and crystallized, and its structure was determined for the first time at 2.2 å resolution. cyt1aa adopts a typical cytolysin fold containing a β-sheet held by two surrounding α-helical layers. the absence of a β-strand (between residues v2 ... | 2011 | 21959261 |
| The presence of Bacillus thuringiensis (Bt) protein in earthworms Eisenia fetida has no deleterious effects on their growth and reproduction. | Earthworms Eisenia fetida, bred in substances with stover of two genetically-engineered Bacillus thuringiensis (Bt) corns (5422Bt1 (Event Bt11) and 5422CBCL (MON810)) expressing Cry1Ab and their near-isogenic non-Bt corn (5422), were used to investigate the non-target effects of Bt corn on soil-dwelling organisms. Cry1Ab concentrations in substances, casts and guts of E. fetida were also investigated by Enzyme-linked immunosorbent assay (ELISA). More than 90% individuals of E. fetida survived ov ... | 2011 | 21955355 |
| Molecular characterization of a novel vegetative insecticidal protein from Bacillus thuringiensis effective against sap-sucking insect pest. | Several isolates of Bacillus thuringiensis (Bt) were screened for the vegetative insecticidal protein (Vip) effective against sap-sucking insect pests. Screening results were based on LC(50) values against cotton aphid (Aphis gossypii), one of the dangerous pests of various crop plants including cotton. Among the isolates, the Bt#BREF24 showed promising results, and upon purification the aphidicidal protein was recognized as a binary toxin. One of the components of this binary toxin was identifi ... | 2011 | 21952370 |
| activation of the caenorhabditis elegans foxo family transcription factor daf-16 by pathogenic bacillus thuringiensis. | the foxo family of transcription factors have recently been implicated in innate immunity, especially in case of daf-16 from the nematode caenorhabditis elegans. however, previous studies with this nematode proposed that daf-16 is not directly activated by pathogens. rather, daf-16 mediates resistance if activated by some other cue as part of a general stress response. we specifically tested this notion by analysis of daf-16 nuclear translocation and thus regulatory activity upon exposure to pat ... | 2011 | 21945834 |
| Recombinant Gluconacetobacter diazotrophicus containing Cry1Ac gene codes for 130-kDa toxin protein. | Recombinant Gluconacetobacter diazotrophicus containing Cry1Ac gene from Bacillus thuringiensis var. kurstaki borne on pKT230, shuttle vector, was generated. PCR amplification of Cry1Ac gene present in recombinant G. diazotrophicus yielded a 278-bp DNA product. The nitrogenase assay has revealed that the recombinant G. diazotrophicus in sugarcane stem produced similar levels of nitrogenase compared to wild-type G. diazotrophicus. The presence of 130-kDa protein in apoplastic fluid from sugarcane ... | 2011 | 21934327 |
| Protist-type lysozymes of the nematode Caenorhabditis elegans contribute to resistance against pathogenic Bacillus thuringiensis. | Pathogens represent a universal threat to other living organisms. Most organisms express antimicrobial proteins and peptides, such as lysozymes, as a protection against these challenges. The nematode Caenorhabditis elegans harbours 15 phylogenetically diverse lysozyme genes, belonging to two distinct types, the protist- or Entamoeba-type (lys genes) and the invertebrate-type (ilys genes) lysozymes. In the present study we characterized the role of several protist-type lysozyme genes in defence a ... | 2011 | 21931778 |
| persistence of bacillus thuringiensis subsp. kurstaki in urban environments following spraying. | bacillus thuringiensis subsp. kurstaki is applied extensively in north america to control the gypsy moth, lymantria dispar. since b. thuringiensis subsp. kurstaki shares many physical and biological properties with bacillus anthracis, it is a reasonable surrogate for biodefense studies. a key question in biodefense is how long a biothreat agent will persist in the environment. there is some information in the literature on the persistence of bacillus anthracis in laboratories and historical test ... | 2011 | 21926205 |
| Insect tolerance to the crystal toxins Cry1Ac and Cry2Ab is mediated by the binding of monomeric toxin to lipophorin glycolipids causing oligomerization and sequestration reactions. | Endotoxins from the soil bacterium Bacillus thuringiensis are used worldwide to control insect pests and vectors of diseases. Despite extensive use of the toxins as sprays and in transgenic crops, their mode of action is still not completely known. Here we show that two crystal toxins binding to different glycoprotein receptors have similar glycolipid binding properties. The glycolipid binding domain was identified in a recombinant peptide representing the domain II of the crystal toxin Cry1Ac ( ... | 2011 | 21925538 |
| RNA interference of an antimicrobial peptide, gloverin, of the beet armyworm, Spodoptera exigua, enhances susceptibility to Bacillus thuringiensis. | Gloverin is known to be an inducible antimicrobial peptide. This study reports a gloverin gene (Seglv) identified from the beet armyworm, Spodoptera exigua. Seglv encodes 175 amino acids with a signal peptide. Its amino acid sequence is highly homologous (>95%) to other known gloverins. Seglv was expressed from egg to adult stages even without immune challenge. Especially, in larval stage, it was expressed in all tested tissues, such as hemocyte, fat body, gut, and epidermis. However, the consti ... | 2011 | 21925182 |
| synergistic activity between bacillus thuringiensis cry6aa and cry55aa toxins against meloidogyne incognita. | plant-parasitic nematodes are the most destructive group of plant pathogens worldwide and are extremely challenging to control. some bacillus thuringiensis crystal proteins are highly toxic to the plant-parasitic nematode meloidogyne incognita. in this study, the nematicidal crystal proteins cry6aa, cry5ba and cry55aa were tested against m. incognita to select the best toxin combination for its management. the results showed that a combination of cry6aa and cry55aa showed significant synergistic ... | 2011 | 21923640 |
| fumonisin b1 toxicity in grower-finisher pigs: a comparative analysis of genetically engineered bt corn and non-bt corn by using quantitative dietary exposure assessment modeling. | in this study, we investigate the long-term exposure (20 weeks) to fumonisin b(1) (fb(1)) in grower-finisher pigs by conducting a quantitative exposure assessment (qea). our analytical approach involved both deterministic and semi-stochastic modeling for dietary comparative analyses of fb(1) exposures originating from genetically engineered bacillus thuringiensis (bt)-corn, conventional non-bt corn and distiller's dried grains with solubles (ddgs) derived from bt and/or non-bt corn. results from ... | 2011 | 21909298 |
| improving cry8ka toxin activity towards the cotton boll weevil (anthonomus grandis). | the cotton boll weevil (anthonomus grandis) is a serious insect-pest in the americas, particularly in brazil. the use of chemical or biological insect control is not effective against the cotton boll weevil because of its endophytic life style. therefore, the use of biotechnological tools to produce insect-resistant transgenic plants represents an important strategy to reduce the damage to cotton plants caused by the boll weevil. the present study focuses on the identification of novel molecules ... | 2011 | 21906288 |
| a quantitative immunopolymerase chain reaction method for detection of vegetative insecticidal protein in genetically modified crops. | vegetative insecticidal protein (vip) is being employed for transgenic expression in selected crops such as cotton, brinjal, and corn. for regulatory compliance, there is a need for a sensitive and reliable detection method, which can distinguish between approved and nonapproved genetically modified (gm) events and quantify gm contents as well. a quantitative immunopolymerase chain reaction (ipcr) method has been developed for the detection and quantification of vip protein in gm crops. the deve ... | 2011 | 21899299 |
| surface architecture of endospores of the bacillus cereus/anthracis/thuringiensis family at the subnanometer scale. | bacteria of the bacillus cereus family form highly resistant spores, which in the case of the pathogen b. anthracis act as the agents of infection. the outermost layer, the exosporium, enveloping spores of the b. cereus family as well as a number of clostridia, plays roles in spore adhesion, dissemination, targeting, and germination control. we have analyzed two naturally crystalline layers associated with the exosporium, one representing the "basal" layer to which the outermost spore layer ("ha ... | 2011 | 21896762 |
| Single cysteine substitution in Bacillus thuringiensis Cry7Ba1 improves the crystal solubility and produces toxicity to Plutella xylostella larvae. | Many Bacillus thuringiensis isolates have no demonstrated toxicity against insects. In this study, a novel holotype crystal protein gene cry7Ba1 was isolated from a 'non-insecticidal'B. thuringiensis strain YBT-978. The Cry7Ba1 protein showed high toxicity against Plutella xylostella larvae after the crystals were dissolved at pH 12.5, suggesting that the 'non-insecticidal' properties of this protein were due to insolubility in the normal insect midgut pH environment. After the C-terminal half o ... | 2011 | 21895913 |
| A novel pathogen-binding gC1qR homolog, FcgC1qR, in the Chinese white shrimp, Fenneropenaeus chinensis. | In vertebrates, the globular "head" of complement component C1q receptor (gC1qR) is a versatile, multiligand binding protein. However, research on its function in invertebrates is limited. In the present study, a full-length cDNA sequence of a novel gC1qR homolog, FcgC1qR, from the Chinese white shrimp Fenneropenaeus chinensis was cloned. Semi-quantitative polymerase chain reaction (PCR) detected FcgC1qR in all examined tissues, with the highest level detected in the intestine. Western blot assa ... | 2012 | 21893092 |
| activity, specificity and structure of i-bth0305i: a representative of a new homing endonuclease family. | novel family of putative homing endonuclease genes was recently discovered during analyses of metagenomic and genomic sequence data. one such protein is encoded within a group i intron that resides in the reca gene of the bacillus thuringiensis 03058-36 bacteriophage. named i-bth0305i, the endonuclease cleaves a dna target in the uninterrupted reca gene at a position immediately adjacent to the intron insertion site. the enzyme displays a multidomain, homodimeric architecture and footprints a dn ... | 2011 | 21890897 |
| Phage-borne factors and host LexA regulate the lytic switch in phage GIL01. | The Bacillus thuringiensis temperate phage GIL01 does not integrate into the host chromosome but exists stably as an independent linear replicon within the cell. Similar to that of the lambdoid prophages, the lytic cycle of GIL01 is induced as part of the cellular SOS response to DNA damage. However, no CI-like maintenance repressor has been detected in the phage genome, suggesting that GIL01 uses a novel mechanism to maintain lysogeny. To gain insights into the GIL01 regulatory circuit, we isol ... | 2011 | 21890699 |
| [Coordinative compounds of zinc with N-substituted thiocarbamoil-N'-pentamethylensulfenamides--activity modifiers of enzymes of proteolytic and glycolytic action]. | The influence of a number of coordinative compounds of zinc with N-substituted thiocarbamoil-N'-pentamethylensulfenamides on activity of elastase, alpha-L-rhamnosidase and alpha-galactosidases evidence for a possibility of their usage as stimulators or inhibitors of enzymes tested have been studied. It was shown that all the compounds in concentration of 0.1 and 0.01% inhibited by 90-100% Bacillus thuringiensis 27-88Els+ elastase activity. [Zn(L2)Br2], [Zn(L1)(NCS)2] and [Zn(L3)(NCS)2] at 20 h e ... | 2011 | 21888052 |
| Identification of a novel aminopeptidase P-like gene (OnAPP) possibly involved in Bt toxicity and resistance in a major corn pest (Ostrinia nubilalis). | Studies to understand the Bacillus thuringiensis (Bt) resistance mechanism in European corn borer (ECB, Ostrinia nubilalis) suggest that resistance may be due to changes in the midgut-specific Bt toxin receptor. In this study, we identified 10 aminopeptidase-like genes, which have previously been identified as putative Bt toxin receptors in other insects and examined their expression in relation to Cry1Ab toxicity and resistance. Expression analysis for the 10 aminopeptidase-like genes revealed ... | 2011 | 21887358 |
| transport of bacillus thuringiensis var. kurstaki via fomites. | the intentional and controlled release of an aerosolized bacterium provides an opportunity to investigate the implications of a biological attack. since 2006, los alamos national laboratory has worked with several urban areas, including fairfax county, va, to design experiments to evaluate biodefense concepts of operations using routine spraying of bacillus thuringiensis var. kurstaki (btk). btk is dispersed in large quantities as a slurry to control the gypsy moth, lymantria dispar. understandi ... | 2011 | 21882970 |
| Increased responsiveness in feeding behaviour of Caenorhabditis elegans after experimental coevolution with its microparasite Bacillus thuringiensis. | Immune responses, either constitutive or induced, are costly. An alternative defence strategy may be based on behavioural responses. For example, avoidance behaviour reduces contact with pathogens and thus the risk of infection as well as the requirement of immune system activation. Similarly, if pathogens are taken up orally, preferential feeding of pathogen-free food may be advantageous. Behavioural defences have been found in many animals, including the nematode Caenorhabditis elegans. We her ... | 2011 | 21880622 |
| Ctriporin, a new anti-methicillin-resistant Staphylococcus aureus peptide from the venom of the scorpion Chaerilus tricostatus. | Antibiotic-resistant microbes, such as methicillin-resistant Staphylococcus aureus, seriously threaten human health. The outbreak of "superbugs" in recent years emphasizes once again the need for the development of new antimicrobial agents or resources. Antimicrobial peptides have an evident bactericidal effect against multidrug-resistant pathogens. In the present study, a new antimicrobial peptide, ctriporin, was cloned and characterized from the venom of the scorpion Chaerilus tricostatus, an ... | 2011 | 21876042 |
| Compatibility of garlic (Allium sativum L.) leaf agglutinin and Cry1Ac d-endotoxin for gene pyramiding. | d-Endotoxins produced by Bacillus thuringiensis (Bt) have been used as bio-pesticides for the control of lepidopteran insect pests. Garlic (Allium sativum L.) leaf agglutinin (ASAL), being toxic to several sap-sucking pests and some lepidopteran pests, may be a good candidate for pyramiding with d-endotoxins in transgenic plants for enhancing the range of resistance to insect pests. Since ASAL shares the midgut receptors with Cry1Ac in Helicoverpa armigera, there is possibility of antagonism in ... | 2011 | 21870043 |
| evaluation of dna extraction methods for bacillus anthracis spores spiked to food and feed matrices at biosafety level 3 conditions. | the dna extraction efficiency from milk, whey, soy, corn gluten meal, wheat powders and heat-treated corn grain that were spiked with bacillus anthracis and bacillus thuringiensis spores was determined. two steps were critical: lysis of the spores and binding of the free dna to the dna binding magnetic beads in the presence of the interfering powders. for the guanidine-thiocyanate based nuclisens lysis buffer from biomerieux we found that between 15 and 30% of the spores survived the lysis step. ... | 2011 | 21864928 |
| cloning, characterization and diversity of insecticidal crystal protein genes of bacillus thuringiensis native isolates from soils of andaman and nicobar islands. | bt strains were isolated from soils of andaman and nicobar islands and characterized by microscopic and molecular methods. diversity was observed both in protein and cry gene profiles, where majority of the isolates showed presence of 65 kda protein band on sds-page while rest of them showed 130, 72, 44, and 29 kda bands. pcr analysis revealed predominance of cry1i and cry7, 8 genes in these isolates. the pcr screening strategy presented here led us to identify putative novel cry genes which cou ... | 2011 | 21858696 |
| Early warning of cotton bollworm resistance associated with intensive planting of Bt cotton in China. | Transgenic crops producing Bacillus thuringiensis (Bt) toxins kill some key insect pests, but evolution of resistance by pests can reduce their efficacy. The predominant strategy for delaying pest resistance to Bt crops requires refuges of non-Bt host plants to promote survival of susceptible pests. To delay pest resistance to transgenic cotton producing Bt toxin Cry1Ac, farmers in the United States and Australia planted refuges of non-Bt cotton, while farmers in China have relied on "natural" r ... | 2011 | 21857961 |
| aedes aegypti membrane-bound alkaline phosphatase expressed in escherichia coli retains high-affinity binding for bacillus thuringiensis cry4ba toxin. | glycosylphosphatidylinositol-linked alkaline phosphatase (gpi-alp) from the epithelial membrane of the larval midgut of aedes aegypti was previously identified as a functional receptor of the bacillus thuringiensis cry4ba toxin. here, heterologous expression in escherichia coli of the cloned alp, lacking the secretion signal and gpi attachment sequences, and assessment of its binding characteristics were further investigated. the 54-kda his tag-fused alp overexpressed as an inclusion body was so ... | 2011 | 21856837 |
| Antibacterial activity of different degree of hydrolysis of palm kernel expeller peptides against spore-forming and non-spore-forming bacteria. | The goal of this study was to determine inhibitory effect of palm kernel expeller (PKE) peptides of different degree of hydrolysis (DH %) against spore-forming bacteria Bacillus cereus, Bacillus circulans, Bacillus coagulans, Bacillus licheniformis, Bacillus megaterium, Bacillus pumilus, Bacillus stearothermophillus, Bacillus subtilis, Bacillus thuringiensis, Clostridium perfringens; and non-spore-forming bacteria Escherichia coli, Lisinibacillus sphaericus, Listeria monocytogenes, Pseudomonas a ... | 2011 | 21848644 |
| shifting paradigm on bacillus thuringiensis toxin and a natural model for enterococcus faecalis septicemia. | the bt toxin is widely used in agriculture both as a spray and in transgenic plants, yet its precise mode of action against lepidopterans is poorly understood. the study by mason et al. [mbio 2(3):e00065-11, 2011] revealed that bt toxin enables an inhabitant of the midgut, enterococcus faecalis, to enter the hemolymph of larvae and cause septicemia, leading to death. | 2011 | 21846827 |
| novel vip3a bacillus thuringiensis (bt) maize approaches high-dose efficacy against helicoverpa zea (lepidoptera: noctuidae) under field conditions: implications for resistance management. | sweet corn, zea mays l., transformed to express a novel vegetative insecticidal protein, vip3a (event mir162, syngenta seeds, inc..), produced by the bacterium, bacillus thuringiensis (bt), was evaluated over four field seasons in maryland and two field seasons in minnesota for efficacy against the corn earworm, helicoverpa zea (boddie). -áhybrids expressing the vip3a protein and pyramided in hybrids also expressing the cry1ab bt protein (event bt11, attribute (-«) , syngenta seeds, inc.) were c ... | 2010 | 21844691 |
| transgenic rice plants expressing cry1ia5 gene are resistant to stem borer (chilo agamemnon). | the stem borer,-áchilo agamemnon-ábles., is the most serious insect pest in-árice-áfields of the egyptian nile delta.-áto induce rice plant resistance to-áchilo agamemnon,-áthe-ácry1ia5-ágene was introduced to rice plants (oryza sativa-ál.).-áthe integration of the-ácry1ia5-ágene into the plant genome was confirmed using pcr and southern blot analyses. the obtained plantlets were transferred to the greenhouse until seeds were collected. northern blot analysis of the t1 plants confirmed the expre ... | 2010 | 21844686 |
| emergence of minor pests becoming major pests in ge cotton in china: what are the reasons? what are the alternatives practices to this change of status? | a recent study in china by lu et al. ( 1) shows that populations of an occasional cotton pest, mirid bugs (heteroptera: miridae), increased following the introduction of genetically engineered (ge) cotton plants. the ge cotton produces a delta-endotoxin from the bacteria bacillus thuringiensis (bt) to control the cotton bollworm. before the introduction of bt cotton in china, mirid bugs were usually controlled by broad-spectrum pesticide sprays targeted against the cotton bollworm, helicoverpa a ... | 2010 | 21844676 |
| effect on soil chemistry of genetically modified (gm) vs. non-gm maize. | the effects of genetically modified (gm) maize (zea mays l.) expressing the bacillus thuringiensis berliner cry1fa2 protein (bt) and phosphinothricin or glyphosate herbicide tolerance on soil chemistry (organic matter, n, p, k and ph), compared with non-gm controls, were assessed in field and pot experiments. in the field experiment, nh(4)(+) was significantly higher in soil under the crop modified for herbicide tolerance compared to the control (mean values of 11 and 9.6 mg n/kg respectively) w ... | 2010 | 21844670 |
| differential alteration of two aminopeptidases n associated with resistance to bacillus thuringiensis toxin cry1ac in cabbage looper. | the soil bacterium bacillus thuringiensis (bt) is the most successfully used biopesticide in agriculture, and its insecticidal protein genes are the primary transgenes used for insect control in transgenic crops. however, evolution of insect resistance to bt toxins threatens the long-term future of bt applications. to date, cases of resistance to bt toxins have been reported in agricultural situations in six insect species, but the molecular basis for these cases of resistance remains unclear. h ... | 2011 | 21844358 |
| developmental studies of transgenic maize expressing cry1ab on the african stem borer, busseola fusca; effects on midgut cellular structure. | background: busseola fusca is a major pest of maize in africa but unfortunately is difficult to control using chemical insecticides. insect-resistant transgenic crops may provide an alternative viable strategy to control this pest. results: recombinant cry1ab (1%) reduced larval weight by 60% over the trial period, while larval weight in the control group increased by 25%; no effects on mortality were observed. insect survival, developmental rate and pupal and adult weight were significantly red ... | 2011 | 21842526 |
| Bacillus thuringiensis Cry3Aa fused to a cellulase-binding peptide shows increased toxicity against the longhorned beetle. | Cry3 class toxins are used extensively for biological control of coleopteran larvae. We previously identified a peptide (PCx) from a phage display library that specifically binds Cx-cellulase from the midgut of Anoplophora glabripennis Motschulsky (Asian longhorn beetle) larvae. Here, we added a DNA fragment that encodes the peptide onto either end of the cry3Aa gene and tested the expressed PCx-Cry3Aa and Cry3Aa-PCx proteins for insecticidal activity in the longhorned beetle. An insect bioassay ... | 2011 | 21842153 |
| parallel evolution of bt toxin resistance in lepidoptera. | despite the prominent and worldwide use of bt insecticidal toxins in agriculture, knowledge of the mechanism by which they kill pests remains incomplete. here we report genetic mapping of a membrane transporter (abcc2) to a locus controlling bt cry1ac toxin resistance in two lepidopterans, implying that this protein plays a critical role in bt function. | 2011 | 21840855 |
| decrease in catalase activity of folsomia candida fed a bt rice diet. | here we report the effects of three bt-rice varieties and their non-bt conventional isolines on biological traits including survival, reproduction, and the activities of three antioxidant enzymes superoxide dismutase, catalase and peroxidase, in the collembolan, folsomia candida. the reproduction was significantly lower when fed kemingdao and huahui1 than those feeding on their non-gm near-isogenic varieties xiushui and minghui63 respectively, this can be explained by the differences of plant co ... | 2011 | 21835518 |
| harpin(pss)-mediated enhancement in growth and biological control of late leaf spot in groundnut by a chlorothalonil-tolerant bacillus thuringiensis sfc24. | chemical and biological approaches have been adopted to increase the growth and yield of crops and reduce loss due to diseases. we have adopted an integrated approach, where both direct antagonism and induced resistance were combined to reduce the incidence of late leaf spot (lls) disease in groundnut caused by phaeoisariopsis personata. chitinolytic chlorothalonil-tolerant soil bacterium bacillus thuringiensis sfc24 (bt sfc24) was manipulated in vitro to express secretable form of elicitor prot ... | 2011 | 21831618 |
| field-evolved resistance to bt maize by western corn rootworm. | crops engineered to produce insecticidal toxins derived from the bacterium bacillus thuringiensis (bt) are planted on millions of hectares annually, reducing the use of conventional insecticides and suppressing pests. however, the evolution of resistance could cut short these benefits. a primary pest targeted by bt maize in the united states is the western corn rootworm diabrotica virgifera virgifera (coleoptera: chrysomelidae). | 2011 | 21829470 |
| specific binding of activated vip3aa10 to helicoverpa armigera brush border membrane vesicles results in pore formation. | helicoverpa armigera is one of the most harmful pests in china. although it had been successfully controlled by cry1a toxins, some h. armigera populations are building up resistance to cry1a toxins in the laboratory. vip3a, secreted by bacillus thuringiensis, is another potential toxin against h. armigera. previous reports showed that activated vip3a performs its function by inserting into the midgut brush border membrane vesicles (bbmv) of susceptible insects. to further investigate the binding ... | 2011 | 21824478 |
| a single major qtl controls expression of larval cry1f resistance trait in ostrinia nubilalis (lepidoptera: crambidae) and is independent of midgut receptor genes. | the european corn borer, ostrinia nubilalis (lepidoptera: crambidae), is an introduced crop pest in north america that causes major damage to corn and reduces yield of food, feed, and biofuel materials. the cry1f toxin from bacillus thuringiensis (bt) expressed in transgenic hybrid corn is highly toxic to o. nubilalis larvae and effective in minimizing feeding damage. a laboratory colony of o. nubilalis was selected for high levels of cry1f resistance (>12,000-fold compared to susceptible larvae ... | 2011 | 21822602 |
| characterization of bacillus thuringiensis l-isoleucine dioxygenase toward the production of useful amino acids. | we determined the enzymatic characteristics of an industrially important biocatalyst, +¦-ketoglutarate-dependent l-isoleucine dioxygenase (ido), which was found to be the enzyme responsible for the generation of (2s,3r,4s)-4-hydroxyisoleucine in bacillus thuringiensis 2e2. depending on the amino acid used as the substrate, ido catalyzed three different types of oxidation reactions: hydroxylation, dehydrogenation, and sulfoxidation. ido stereoselectively hydroxylated several hydrophobic aliphatic ... | 2011 | 21821743 |
| ultrasensitive electrochemical detection of bacillus thuringiensis transgenic sequence based on in situ ag nanoparticles aggregates induced by biotin-streptavidin system. | a novel electrochemical biosensor was developed for detecting short dna oligonucleotide of bacillus thuringiensis (bt) transgenic sequence based on ag nanoparticle aggregates. to fabricate this dna biosensor, the thiol-modified capture dna (cdna) was first anchored on gold (au) electrode, and then the target dna (tdna) was hybridized with the immobilized cdna. subsequently, the probe dna (pdna) functionalized by biotinylated ag nanoparticle was associated with the fixed tdna, and the single ag n ... | 2011 | 21821408 |
| insertion of an intact cr1 retrotransposon in a cadherin gene linked with bt resistance in the pink bollworm, pectinophora gossypiella. | three mutations in the pectinophora gossypiella cadherin gene pgcad1 are linked with resistance to bacillus thuringiensis (bt) toxin cry1ac. here we show that the r3 mutation entails recent insertion into pgcad1 of an active chicken repeat (cr1) retrotransposon, designated cr1-1_pg. unlike most other cr1 elements, cr1-1_pg is intact, transcribed by a flanking promoter, contains target site duplications and has a relatively low number of copies. examination of transcripts from the pgcad1 locus re ... | 2011 | 21815956 |
| field evaluation of bactimos pt against chironomid midge (diptera: chironomidae) larvae in residential ponds. | we evaluated bactimos pt (bacillus thuringiensis subsp. israelensis [bti]) against larval populations of glyptotendipes paripes at 30 kg/ha in man-made lakes on hilton head island, sc. three treatments were "whole-pond" treatments, while the 4th consisted of treating a "band" along the edge of a pond where significant larval populations had been observed. larval populations were reduced by an average of 95% at day 7, 70% at day 14, and 50% at day 21 posttreatment in the whole-pond treatments. in ... | 2011 | 21805856 |
| comparison of morning and evening larvicide applications on black fly (diptera: simuliidae) mortality. | the downstream movement, or drift, of larval black flies as well as many other aquatic insects has been well documented. this phenomenon has most often been associated with the dusk-to-overnight time frame. operationally, larvicide applications targeting black flies are typically initiated early in the day and can extend until near sunset. to determine if larvicide applications conducted late in the day would be affected by the drift behavior of larval black flies, 6 larvicide applications were ... | 2011 | 21805855 |
| high prevalence of bacterial spore-formers active against mosquito larvae in temporary monsoon flooded sites in orissa, india. | different ecosystems were probed in the vicinity of the city of bhubaneswar in the indian state of orissa for the presence of bacterial spore-formers with activity against mosquito larvae. the most productive sites were places that were flooded during the monsoon season, including roadside ditches and shorelines of ponds. among 630 isolates screened, 44 (7%) showed larvicidal activity against larvae of aedes aegypti. the specific activity of the bacterial spore-formers varied greatly. isolates w ... | 2011 | 21805851 |
| construction of a bacillus thuringiensis genetically-engineered strain harbouring the secreted cry1ia delta-endotoxin in its crystal. | unlike other bacillus thuringiensis cry proteins, cry1ia does not form a crystal since it is a secreted delta-endotoxin. we have engineered a cry1iac chimeric protein by substituting the c-terminal part of cry1ia by the corresponding cry1ac part. when expressed in an acrystalliferous b. thuringiensis strain, cry1iac did not crystallize, but when expressed in the crystalliferous strain bns3, the chimeric protein co-crystallized with the endogenous cry1a delta-endotoxins forming a typical bipyrami ... | 2011 | 21805183 |
| dna capturing machinery through spore-displayed proteins. | aims: the purpose of this study was to develop a general method for the facile development of a new dna biosensor which utilizes streptavidin-displayed spores as a molecular machinery. methods and results: fluorescence spectroscopy was used as a monitoring tool for the streptavidin displayed on the surface of bacillus thuringiensis spores and as a diagnosis method for dna detection. as a proof-of-concept, four pathogenic bacteria including pseudomonas aeruginosa, acinetobacter baumannii, esche ... | 2011 | 21801185 |
| site factors and management influence short-term host resistance to spruce budworm, choristoneura fumiferana (clem.), in a species-specific manner. | background: this study examined the interactions between thinning and soil drainage classes on the resistance of balsam fir, abies balsamea (l.) mill, white spruce, picea glauca (moench) voss, and black spruce, p. mariana (mill.) bsp, to spruce budworm, choristoneura fumiferana (clem.), defoliation 1 year after treatment. to estimate host tree resistance, foliage production and larval foliage consumption were determined to generate an index of resistance quantifying the amount of residual foliag ... | 2011 | 21796758 |