Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| resistance and behavioural response of plutella xylostella (lepidoptera: plutellidae) populations to bacillus thuringiensis formulations. | insecticide resistance is probably the major cause of control failure of plutella xylostella (l.) in brazil. in most production regions, the use of chemicals has been the prevalent method of control, with reduced efficacy through cropping seasons, even for the most recent use of products based on bacillus thuringiensis (bt). the current status of the resistance to these products was assessed, as well as the behavioural response of p. xylostella populations to bt sprays. | 2014 | 23813721 |
| combinatorial effect of bacillus thuringiensis kurstaki and photorhabdus luminescens against spodoptera littoralis (lepidoptera: noctuidae). | spodoptera littoralis, one of the major pests of many important crop plants, is more susceptible to bacillus thuringiensis aizawai delta-endotoxins than to those of bacillus thuringiensis kurstaki. within the framework of the development of efficient bioinsecticides and the prevention against insect resistance, we tested the effect of mixing b. thuringiensis kurstaki delta-endotoxins and photorhabdus luminescens cells on s. littoralis growth. the obtained results showed that the growth inhibitio ... | 2014 | 23908000 |
| molecular characterization of a short peptidoglycan recognition protein (pgrp-s) from asian corn borer (ostrinia furnacalis) and its role in triggering propo activity. | peptidoglycan recognition proteins (pgrps) are non-specific immune molecules of insects, and vertebrates etc., but are not present in plants and nematodes. in the current experiment, a pgrp dna sequence (2,910 bp containing four exons) was identified from genomic dna library of asian corn borer, ostrinia furnacalis, and a full-length cdna programming pgrp was cloned (designed as ofpgrp-s) with an open reading frame of 579 bp, having 192 amino acid. this inferred amino acid sequence showed maximu ... | 2014 | 23907718 |
| no effects of bacillus thuringiensis maize on nontarget organisms in the field in southern europe: a meta-analysis of 26 arthropod taxa. | maize with the insecticidal properties of the entomopathogenic bacterium bacillus thuringiensis berliner, known as bt maize, has been sown in europe since 1998. for several years, eu and spanish regulations have required laboratory and field trials to assess risks of genetically modified crops for nontarget organisms prior to their authorization. thirteen field trials were conducted in spain to measure the effects of bt maize on a broad range of arthropod taxa; no effects were found in accordanc ... | 2014 | 23904218 |
| the effect of nitrogen rate on transgenic corn cry3bb1 protein expression. | combining herbicide-resistant and bacillus thuringiensis (bt) traits in corn (zea mays l.) hybrids may affect insect resistance management owing to volunteer corn. some bt toxins may be expressed at lower levels by nitrogen-deficient corn roots. corn plants with sublethal levels of bt expression could accelerate the evolution of bt resistance in target insects. the present objective was to quantify the concentration of bt (cry3bb1) in corn root tissue with varying tissue nitrogen concentrations. | 2014 | 23868342 |
| new and old microbial communities colonizing a seventeenth-century wooden church. | the north of romania is known for its wooden churches dating from the seventeenth and eighteenth centuries. their deterioration constitutes a major problem due to their value for the cultural heritage. the microbial community from a seventeenth-century wooden church (nicula, romania) was investigated by characterization of uncultivated and cultivated bacteria using 16s rdna sequence analysis. the study revealed not only the prevalence of the bacillus thuringiensis strain iam 12077 but also the p ... | 2014 | 23846554 |
| the influence of insecticides on the viability of entomopathogenic nematodes (rhabditida: steinernematidae and heterorhabditidae) under laboratory conditions. | in order to increase our knowledge on the susceptibility of entomopathogenic nematode (epn) species to agrochemicals, the compatibility of the infective juveniles (ijs) of the epn (steinernema and heterorhabditis) with eight chemical and bio-insecticides was investigated under laboratory conditions. the effect of direct ij exposure to insecticides for 6 and 24 h was tested in a petri dish at 15, 20 and 25 °c. | 2014 | 23873740 |
| narrow terahertz attenuation signatures in bacillus thuringiensis. | terahertz absorption signatures from culture-cultivated bacillus thuringiensis were measured with a thz photomixing spectrometer operating from 400 to 1200 ghz. we observe two distinct signatures centered at ∼955 and 1015 ghz, and attribute them to the optically coupled particle vibrational resonance (surface phonon-polariton) of bacillus spores. this demonstrates the potential of the thz attenuation signatures as "fingerprints" for label-free biomolecular detection. | 2014 | 23821459 |
| further research on the biological function of inclusion bodies of anomala cuprea entomopoxvirus, with special reference to the effect on the insecticidal activity of a bacillus thuringiensis formulation. | entomopoxviruses (evs) form two types of inclusion body: spheroids, which contain virions, and spindles, which do not. the authors tested whether the spindles from a coleopteran ev, anomala cuprea ev (acev), enhanced the insecticidal activity of a commercial bacillus thuringiensis (bt) formulation and the susceptibility of scarabaeid pest species in japan to the virus's spheroids, to assess whether acev inclusion bodies are potential biological control agents for pest insects. | 2014 | 23424042 |
| current status of genetic engineering in cotton (gossypium hirsutum l): an assessment. | cotton is considered as the foremost commercially important fiber crop and is deemed as the backbone of the textile industry. the productivity of cotton crop, worldwide, is severely hampered by the occurrence of pests, weeds, pathogens apart from various environmental factors. several beneficial agronomic traits, viz., early maturity, improved fiber quality, heat tolerance, etc. have been successfully incorporated into cotton varieties employing conventional hybridization and mutation breeding. ... | 2014 | 23190258 |
| intravital imaging of bacillus thuringiensis cry1a toxin binding sites in the midgut of silkworm. | identification of the resistance mechanism of insects against bacillus thuringiensis cry1a toxin is becoming an increasingly challenging task. this fact highlights the need for establishing new methods to further explore the molecular interactions of cry1a toxin with insects and the receptor-binding region of cry1a toxins for their wider application as biopesticides and a gene source for gene-modified crops. in this contribution, a quantum dot-based near-infrared fluorescence imaging method has ... | 2014 | 24252542 |
| heliothis virescens and bt cotton in the united states. | the tobacco budworm (tbw), heliothis virescens (f.), has been responsible for substantial economic losses, environmental pollution and a great challenge to the united states' economy, environment, researchers and cotton and tobacco producers during most of the past two hundred years. if a historical description of this pest problem should be written, it would necessarily be divided into two main events; the pre- and post-bacillus thuringiensis-expressing (bt)-cotton era. before the advent of bt- ... | 2014 | 22892654 |
| inducible expression of a fusion gene encoding two proteinase inhibitors leads to insect and pathogen resistance in transgenic rice. | plant proteinase inhibitors (pis) are considered as candidates for increased insect resistance in transgenic plants. insect adaptation to pi ingestion might, however, compromise the benefits received by transgenic expression of pis. in this study, the maize proteinase inhibitor (mpi), an inhibitor of insect serine proteinases, and the potato carboxypeptidase inhibitor (pci) were fused into a single open reading frame and introduced into rice plants. the two pis were linked using either the proce ... | 2014 | 24237606 |
| enzymatic hydrolysis of molecules associated with bacterial quorum sensing using an acyl homoserine lactonase from a novel bacillus thuringiensis strain. | n-acyl homoserine lactones are key components of quorum sensing, the bacterial communication system. this communication mechanism regulates the expression of genes, including those involved in virulence and biofilm formation. this system can be interrupted by the action of enzymes that hydrolyze the signaling molecules. in this work, we studied the enzymatic properties of a recombinant ahl-lactonase from bacillus thuringiensis strain 147-11516, using substrates with acyl chains of different leng ... | 2014 | 24233057 |
| identification of genes required by bacillus thuringiensis for survival in soil by transposon-directed insertion site sequencing. | transposon-directed insertion site sequencing was used to identify genes required by bacillus thuringiensis to survive in non-axenic plant/soil microcosms. a total of 516 genetic loci fulfilled the criteria as conferring survival characteristics. of these, 127 (24.6 %) were associated with uptake and transport systems; 227 loci (44.0 %) coded for enzymatic properties; 49 (9.5 %) were gene regulation or sensory loci; 40 (7.8 %) were structural proteins found in the cell envelope or had enzymatic ... | 2014 | 24310935 |
| the basis for rootstock resilient to capnodis species: screening for genes encoding δ-endotoxins from bacillus thuringiensis. | conventional methods often fail to control the flatheaded borers capnodis spp., major pests of stone fruit trees; the larvae are protected from insecticides and predation because they feed deep in the roots. a potential solution is transgenic trees producing in their roots toxic compounds such as cry proteins of bacillus thuringiensis (bt). | 2014 | 24293325 |
| persistence of the spores of b. thuringiensis subsp. kurstaki from foray bioinsecticide in gleysol soil and on leaves. | the aim of this study was to determine how long the spores of bacillus thuringiensis subsp. kurstaki hd-1 from foray bioinsecticide persist in soil and on leaf surface after application of the bioinsecticide in an oak forest. foray 04 ul was sprayed over a 195-hectare oak forest on the krotoszyn plateau in poland. b. thuringiensis was isolated from soil samples and tree leaves taken from randomly chosen sites. b. thuringiensis subsp. kurstaki hd-1 in the samples was identified upon clonal analys ... | 2014 | 24291630 |
| proteomics study of silver nanoparticles toxicity on bacillus thuringiensis. | emerging technologies in functional genomics and proteomics provide a way of achieving high-throughput analyses, understanding effects on protein populations and sub-populations and follow up environmental stresses. to accomplish these, the action of homemade spherical silver nanoparticles colloidal suspension (agnps) against bacillus thuringiensis (isolate from oryza sativa l. rhizosphere) was investigated by a proteomic approach (2-de and nanolc/ft-icr ms identification). thirty four responsiv ... | 2014 | 24290895 |
| bioavailability of the anti-clostridial bacteriocin thuricin cd in gastrointestinal tract. | thuricin cd is a two component narrow spectrum bacteriocin comprising two peptides with targeted activity against clostridium difficile. this study examined the bioavailability of thuricin with a view to developing it as an effective antimicrobial against intestinal infection. one of the peptides, trn-β, was found to be degraded by the gastric enzymes pepsin and α-chymotrypsin both in vitro and in vivo, whereas trn-α was resistant to digestion by these enzymes and hence was detected in the intes ... | 2014 | 24287693 |
| structural, evolutionary and functional analysis of apn genes in the lepidoptera bombyx mori. | aminopeptidases n (apns), the receptors of bacillus thuringiensis (bt) toxin in the lepidopteran midgut, are involved in the bt pathogen infection mechanism. in the present work, we screened 102 apns from silkdb, butterflybase and monarchbase; 16 apns were identified from the silkworm (bombyx mori) and 24 from the monarch butterfly (danaus plexippus). syntenic and phylogenetic tree analysis showed that apn genes have developed multi-family genes before evolutionary divergence of the lepidoptera. ... | 2014 | 24286860 |
| a novel cry9aa with increased toxicity for spodoptera exigua (hübner). | cry9aa, produced by bacillus thuringiensis is reported to be not active against spodoptera exigua (beet armyworm). in this study we have cloned a new cry9aa5 gene encoding a protoxin with increased activity against s. exigua as compared to cry9aa1. when aligned to cry9aa1, four amino acid substitutions in domain i and one substitution in the c-terminal protein extension of cry9aa5 were identified. toxicity of cry9aa5, produced in recombinant escherichia coli was assessed and compared to the acti ... | 2014 | 24286660 |
| genomic analysis of a phage and prophage from a bacillus thuringiensis strain. | bacteriophages have been found to be the most abundant and also potentially most diverse biological entities on earth. in the present study, bacillus phages were isolated rapidly and shown to have a high degree of diversity. the genomes of a newly isolated phage, phicm3, and a prophage, procm3, from the bacillus thuringiensis strain ym-03 were sequenced and characterized. comparative genome analysis showed that the phicm3 genome is highly similar to the genomes of eight other bacillus phages and ... | 2014 | 24285088 |
| uv light and urban pollution: bad cocktail for mosquitoes? | mosquito breeding sites consist of water pools, which can either be large open areas or highly covered ponds with vegetation, thus with different light exposures combined with the presence in water of xenobiotics including polycyclic aromatic hydrocarbons (pahs) generated by urban pollution. uv light and pahs are abiotic factors known to both affect the mosquito insecticide resistance status. nonetheless, their potential combined effects on the mosquito physiology have never been investigated. t ... | 2014 | 24275062 |
| characterization of four midgut aminopeptidase n isozymes from ostrinia furnacalis strains with different susceptibilities to bacillus thuringiensis. | the full-length cdna of four ofapn aminopeptidases were cloned and sequenced from susceptible and resistant ostrinia furnacalis strains. four sequences were identified as apn because they shared the common structural features with apn from lepidoptera, including the signal peptide, gpi anchor signal, the zinc binding/gluzincin motif hex2hx18e and the gluzincin aminopeptidase motif gamen. compared with apn sequences from the susceptible strain, there were 9, 5, 10 and 12 amino acid variations in ... | 2014 | 24269376 |
| increased survival in the red flour beetle after oral priming with bacteria-conditioned media. | immune priming is defined as enhanced protection upon secondary exposure to a pathogen. such enhanced resistance after prior exposure has been demonstrated for a number of insect species including the red flour beetle, tribolium castaneum. in testing this phenomenon, the majority of studies have focused on introducing the pathogen into the insect's hemocoel via septic wounding through the cuticle. although such septic injury can occur in nature, many pathogens enter their hosts via the oral rout ... | 2014 | 24216503 |
| toxicity and mode of action of insecticidal cry1a proteins from bacillus thuringiensis in an insect cell line, cf-1. | bacillus thuringiensis cry toxins are insecticidal proteins used to control insect pests. the interaction of cry toxins with the midgut of susceptible insects is a dynamic process involving activation of the toxin, binding to midgut receptors in the apical epithelium and conformational changes in the toxin molecule, leading to pore formation and cell lysis. an understanding of the molecular events underlying toxin mode of action is essential for the continued use of cry toxins. in this work, we ... | 2014 | 24189038 |
| bacillus thuringiensis subsp. sichuansis strain mc28 produces a novel crystal protein with activity against culex quinquefasciatus larvae. | the bacillus thuringiensis subsp. sichuansis mc28 strain produces spherical parasporal crystals during sporulation and exhibits remarkable insecticidal activity against dipteran and lepidopteran pests. we characterized a novel cry gene (cry69aa1), which was found in the pmc95 plasmid of the mc28 strain. the cry69aa1 gene was inserted into a shuttle vector (pstk) and expressed in an acrystalliferous mutant b. thuringiensis hd73⁻. in this transformant, a large number of spherical parasporal crysta ... | 2014 | 24185745 |
| biosynthesis of silver nanoparticles using bacillus thuringiensis against dengue vector, aedes aegypti (diptera: culicidae). | the present study reveals the larvicidal activity of silver nanoparticles (agnps) synthesized by bacillus thuringiensis (bt) against aedes aegypti responsible for the diseases of public health importance. the bt-agnps were characterized by using uv-visible spectrophotometer followed by scanning electron microscopy (sem) and energy-dispersive x-ray (edx) spectroscopy. a surface plasmon resonance spectrum of agnps was obtained at 420 nm. the particle sizes were measured through sem imaging ranging ... | 2014 | 24173811 |
| single and fused transgenic bacillus thuringiensis rice alter the species-specific responses of non-target planthoppers to elevated carbon dioxide and temperature. | the approval of transgenic bacillus thuringiensis (bt) rice by china was momentous for biotech crops, although it has yet to be approved for commercial production. non-target pest problems in rice paddies, such as the three ecologically similar species of planthoppers nilaparvata lugens, laodelphax striatellus and sogatella furcifera, could become increasingly serious under global climate change. fused (cry1ab/cry1ac) and single (cry1ab) transgenic bt rice were evaluated for effects on species-s ... | 2014 | 24136625 |
| estimating the frequency of cry1f resistance in field populations of the european corn borer (lepidoptera: crambidae). | transgenic corn hybrids that express toxins from bacillus thuringiensis (bt) have suppressed european corn borer populations and reduced the pest status of this insect throughout much of the us corn belt. a major assumption of the high-dose/refuge strategy proposed for insect resistance management and bt corn is that the frequency of resistance alleles is low so that resistant pests surviving exposure to bt corn will be rare. | 2014 | 24124030 |
| selection and characterisation of an hd1-like bacillus thuringiensis isolate with a high insecticidal activity against spodoptera littoralis (lepidoptera: noctuidae). | spodoptera littoralis (boisduval) larvae are known by their susceptibility to bacillus thuringiensis subsp. aizawai strains. in order to prevent the appearance of b. thuringiensis (bt) resistance and to develop economical bt-based biopesticides, the selection and the characterisation of a b. thuringiensis isolate toxic against s. littoralis larvae and overproducing δ-endotoxins were investigated. | 2014 | 24124020 |
| detection of minimum activity fragment of a novel cry7ab3 protein specific to henosepilachna vigintioctomaculata (coleopteran: coccinellidae). | bacillus thuringiensis cry7ab3 toxin has insecticidal activity against larvae of henosepilachna vigintioctomaculata. cry7ab3 toxin is solubilized under alkaline condition and activated by proteases within the larval gut. in order to assess the functions of the n- and c-terminal regions, several n- and c-terminal truncated forms of cry7ab3 were constructed. it was determined that amino acid removal at the n-terminal, which disrupt the α-helico structure, resulted in the inactivation of the protei ... | 2014 | 24123206 |
| transcriptional profile of tomato roots exhibiting bacillus thuringiensis-induced resistance to ralstonia solanacearum. | activation of sa-dependent signaling pathway and suppression of ja-dependent signaling pathway seem to play key roles inb. thuringiensis-induced resistance tor. solanacearumin tomato plants. bacillus thuringiensis, a well-known and effective bio-insecticide, has attracted considerable attention as a potential biological control agent for the suppression of plant diseases. treatment of tomato roots with a filter-sterilized cell-free filtrate (cf) of b. thuringiensis systemically suppresses bacter ... | 2014 | 24121643 |
| midgut transcriptome response to a cry toxin in the diamondback moth, plutella xylostella (lepidoptera: plutellidae). | to investigate the response of plutella xylostella transcriptome in defending against a bt toxin, high-throughput rna-sequencing was carried out to examine cry1ac-susceptible and -resistant strains. the comparative analysis indentified over 2900 differentially expressed unigenes (deus) between these two strains. gene ontology analysis placed these unigenes primarily into cell, cell part, organelle, binding, catalytic, cellular process, metabolic process, and response to stimulus categories. base ... | 2014 | 24120626 |
| importance of polarity of the α4-α5 loop residue-asn(166) in the pore-forming domain of the bacillus thuringiensis cry4ba toxin: implications for ion permeation and pore opening. | bacillus thuringiensis cry4ba toxin is lethal to mosquito-larvae by forming ion-permeable pores in the target midgut cell membrane. previously, the polarity of asn(166) located within the α4-α5 loop composing the cry4ba pore-forming domain was shown to be crucial for larvicidal activity. here, structurally stable-mutant toxins of both larvicidal-active (n166d) and inactive (n166a and n166i) mutants were fplc-purified and characterized for their relative activities in liposomal-membrane permeatio ... | 2014 | 24120447 |
| construction and characterization of the interdomain chimeras using cry11aa and cry11ba from bacillus thuringiensis and identification of a possible novel toxic chimera. | three structural domains of mosquitocidal cry11aa and cry11ba from bacillus thuringiensis were exchanged to produce interdomain chimeras [baa (11ba/11aa/11aa), aba (11aa/11ba/11aa), aab (11aa/11aa/11ba), abb (11aa/11ba/11ba), bab (11ba/11aa/11ba), bba (11ba/11ba/11aa]. chimeras bab, baa, bba, and aab formed inclusion bodies in the crystal-negative b. thuringiensis host and produced expected protein bands on sds-page gel. however, no inclusion body or target protein could be found for chimeras ab ... | 2014 | 24068502 |
| characterization and potential application in mercury bioremediation of highly mercury-resistant marine bacterium bacillus thuringiensis pw-05. | bacillus thuringiensis pw-05 was isolated from the odisha coast and was found to resist 50 ppm of hg as hgcl2 as well as higher concentrations of cdcl2, znso4, pbno3 and na2haso4. resistance towards several antibiotics, viz amoxycillin, ampicillin, methicillin, azithromycin and cephradine (cv) was also observed. the mer operon possessed by most of the mercury-resistant bacteria was also found in this isolate. atomic absorption spectroscopy revealed that the isolate can volatilize >90 % of inorga ... | 2014 | 24114385 |
| cadherin adcad1 in alphitobius diaperinus larvae is a receptor of cry3bb toxin from bacillus thuringiensis. | bacillus thuringiensis (bt) cry proteins are used as components of biopesticides or expressed in transgenic crops to control diverse insect pests worldwide. these cry toxins bind to receptors on the midgut brush border membrane and kill enterocytes culminating in larval mortality. cadherin proteins have been identified as cry toxin receptors in diverse lepidopteran, coleopteran, and dipteran species. in the present work we report a 185 kda cadherin (adcad1) from larvae of the lesser mealworm (al ... | 2014 | 24225445 |
| a genetically modified broad-spectrum strain of bacillus thuringiensis toxic against holotrichia parallela, anomala corpulenta and holotrichia oblita. | cry8ea1 from bacillus thuringiensis strain bt185 has insecticidal activity against holotrichia parallela. cry8ca2 from strain hbf-1 is effective against anomala corpulenta. cry8ga1 from strain hbf-18 is toxic to h. oblita. given the need to broaden the spectrum of b. thuringiensis, a broad-spectrum coleopteran active strain of b. thuringiensis, biot185, engineered to express multiple cry genes, including cry8ea1, cry8fa1 and cry8ca2, was created by homologous recombination introducing the cry8ca ... | 2014 | 24030167 |
| eliminating host-mediated effects demonstrates bt maize producing cry1f has no adverse effects on the parasitoid cotesia marginiventris. | the fall armyworm, spodoptera frugiperda (j. e. smith) (lepidoptera: noctuidae), is an important pest of maize in the united states and many tropical areas in the western hemisphere. in 2001, herculex i(®) (cry1f) maize was commercially planted in the united states to control lepidoptera, including s. frugiperda. in 2006, a population of s. frugiperda was discovered in puerto rico that had evolved resistance to cry1f maize in the field, making it the first well-documented case of an insect with ... | 2014 | 24026808 |
| validation of an extraction method for cry1ab protein from soil. | corn expressing insecticidal proteins derived from bacillus thuringiensis (bt corn) has increased in usage in the united states from 8% of total corn acreage in 1996 to 67% in 2012. because of this increase, it is important to be able to monitor the fate and transport of the insecticidal bt proteins to evaluate environmental exposure and effects. accurate and validated methods are needed to quantify these proteins in environmental matrices. a method to extract bt cry1ab proteins from 3 soil type ... | 2014 | 23996731 |
| tolerance to individual and joint effects of arsenic and bacillus thuringiensis subsp. israelensis or lysinibacillus sphaericus in culex mosquitoes. | arsenic contamination of global water supplies has come to the forefront in policy decisions in recent decades. however, the effects of arsenic on lower trophic levels of insects inhabiting contaminated ecosystems are not well understood. one approach to document both acute and sublethal effects of toxicants like arsenic is to assay them in combination with microbial pathogens to evaluate shifts in survival curves of the test organisms. larvae of culex quinquefasciatus and culex tarsalis were re ... | 2014 | 23956096 |
| insecticide resistance status in the major west nile virus vector culex pipiens from greece. | one of the largest west nile virus outbreaks in europe occurred in greece in 2010. use of insecticides against culex pipiens was substantially scaled up, as an emergency tool. although mosquito control has been based on insecticides for several decades in greece, insecticide resistance data are not available. | 2014 | 23788440 |
| emira: ecologic malaria reduction for africa - innovative tools for integrated malaria control. | background malaria control is based on early treatment of cases and on vector control. the current measures for malaria vector control in africa are mainly based on long-lasting insecticide treated nets (llins) and to a much smaller extent on indoor residual spraying (irs). a third pillar in the fight against the malaria vector, larval source management (lsm), has virtually not been used in africa since the ban of ddt in the 1960s. within the light of recent who recommendations for bacillus thur ... | 2014 | 28672461 |
| understanding successful resistance management: the european corn borer and bt corn in the united states. | the european corn borer, ostrinia nubilalis hübner (lepidoptera: crambidae) has been a major pest of corn and other crops in north america since its accidental introduction nearly a hundred years ago. wide adoption of transgenic corn hybrids that express toxins from bacillus thuringiensis, referred to as bt corn, has suppressed corn borer populations and reduced the pest status of this insect in parts of the corn belt. continued suppression of this pest, however, will depend on managing potentia ... | 2014 | 22688691 |
| the design and implementation of insect resistance management programs for bt crops. | cotton and corn plants with insect resistance traits introduced through biotechnological methods and derived from the bacterium bacillus thuringiensis (bt) have been widely adopted since they were first introduced in 1996. because of concerns about resistance evolving to these bt crops, they have been released with associated irm programs that employ multiple components and reflect the input of academic, industrial and regulatory experts. this paper summarizes the current status of bt crop techn ... | 2014 | 22688689 |
| western corn rootworm and bt maize: challenges of pest resistance in the field. | crops genetically engineered to produce insecticidal toxins from the bacterium bacillus thuringiensis (bt) manage many key insect pests while reducing the use of conventional insecticides. one of the primary pests targeted by bt maize in the united states is the western corn rootworm, diabrotica virgifera virgifera leconte. beginning in 2009, populations of western corn rootworm were identified in iowa, usa that imposed severe root injury to cry3bb1 maize. subsequent laboratory bioassays reveale ... | 2014 | 22688688 |
| extended monitoring of resistance to bacillus thuringiensis cry1ab maize in diatraea saccharalis (lepidoptera: crambidae). | the sugarcane borer, diatraea saccharalis (f.), is a major target of transgenic maize expressing bacillus thuringiensis (bt) proteins in south america and the mid-southern region of the united states. during 2007-2009, a total of 986 feral individuals of d. saccharalis were collected from maize fields in six locations of louisiana and mississippi and examined for resistance to cry1ab maize using f 1/f 2 screens. major resistance alleles to cry1ab maize in the populations sampled from non-bt maiz ... | 2014 | 22688686 |
| sustained susceptibility of pink bollworm to bt cotton in the united states. | evolution of resistance by pests can reduce the benefits of transgenic crops that produce toxins from bacillus thuringiensis (bt) for insect control. one of the world's most important cotton pests, pink bollworm (pectinophora gossypiella), has been targeted for control by transgenic cotton producing bt toxin cry1ac in several countries for more than a decade. in china, the frequency of resistance to cry1ac has increased, but control failures have not been reported. in western india, pink bollwor ... | 2014 | 22572905 |
| genetically engineered vegetables expressing proteins from bacillus thuringiensis for insect resistance: successes, disappointments, challenges and ways to move forward. | genetically engineered (ge) insect-resistant crops that express proteins from bacillus thuringiensis (bt) have been widely adopted in the two field crops currently commercially available, bt cotton and bt corn. however, the development and commercialization of bt vegetables has lagged in comparison, which is unfortunate since vegetables tend to be insecticide-intensive crops due to high pest pressure and cosmetic standards required for the market. while it is often stated that consumer choice ha ... | 2014 | 22538234 |
| toxicity and cross-resistance of insecticides to cry2ab-resistant and cry2ab-susceptible helicoverpa armigera and helicoverpa punctigera (lepidoptera: noctuidae). | since 2004-2005 cotton expressing cry1ac and cry2ab insecticidal proteins from the bacterium bacillus thuringiensis has been commercially available in australia to manage the target pests helicoverpa armigera (hübner) and helicoverpa punctigera (wallengren). in both target species, the frequency of alleles conferring resistance to cry2ab is unexpectedly high in field populations. a significant challenge for managing these pests would occur if resistance to cry2ab toxins inadvertently selected fo ... | 2014 | 26309283 |
| geographical and temporal variability in susceptibility to cry1f toxin from bacillus thuringiensis in spodoptera frugiperda (lepidoptera: noctuidae) populations in brazil. | the genetically modified maize tc1507 event with the cry1f gene (cry1f maize) has been used to control spodoptera frugiperda (j.e. smith) (lepidoptera: noctuidae) in brazil since the 2009-2010 cropping season. as part of the insect resistance management program, we conducted studies to determine the baseline susceptibility to cry1f before the widespread planting of cry1f maize. subsequently, we evaluated the geographical and temporal variability of susceptibility to this toxin in populations of ... | 2014 | 26470084 |
| thuringiensin: a thermostable secondary metabolite from bacillus thuringiensis with insecticidal activity against a wide range of insects. | thuringiensin (thu), also known as β-exotoxin, is a thermostable secondary metabolite secreted by bacillus thuringiensis. it has insecticidal activity against a wide range of insects, including species belonging to the orders diptera, coleoptera, lepidoptera, hymenoptera, orthoptera, and isoptera, and several nematode species. the chemical formula of thu is c22h32o19n5p, and it is composed of adenosine, glucose, phosphoric acid, and gluconic diacid. in contrast to the more frequently studied ins ... | 2014 | 25068925 |
| synthetic fusion-protein containing domains of bt cry1ac and allium sativum lectin (asal) conferred enhanced insecticidal activity against major lepidopteran pests. | different transgenic crop plants, developed with δ-endotoxins of bacillus thuringiensis (bt) and mannose-specific plant lectins, exhibited significant protection against chewing and sucking insects. in the present study, a synthetic gene (cry-asal) encoding the fusion-protein having 488 amino acids, comprising di and dii domains from bt cry1ac and allium sativum agglutinin (asal), was cloned and expressed in escherichia coli. ligand blot analysis disclosed that the fusion-protein could bind to m ... | 2014 | 24355805 |
| dermal toxicity, eye and dermal irritation and skin sensitization evaluation of a new formulation of bacillus thuringiensis var israelensis sh-14. | bacillus thuringiensis (bt) is the best known and most widely used of all pesticidal microbes. the aim of this study was to assess the toxicity of a new formulation of bacillus thuringiensis var israelensis sh-14 in rats through acute dermal toxicity, dermal and eye irritation experiments. the acute dermal toxicity and dermal and eye irritation studies were performed using rabbits according to the united states environmental protection agency guidelines 885.3100, 870.2500 and 870.2500, respectiv ... | 2014 | 24342232 |
| complete genome sequence of bacillus thuringiensis ybt-1518, a typical strain with high toxicity to nematodes. | bacillus thuringiensis is a ubiquitous spore-forming bacterium and has been widely used as a biopesticide for controlling agricultural insects by the production of insecticidal crystal proteins (icps). b. thuringiensis ybt-1518 displays effective toxicity to nematodes. this strain harbors three nematicidal crystal protein genes, including cry55aa1, cry6aa2 and cry5ba2, and also contains multiple potential virulence factors. here, we report the complete genome sequence of b. thuringiensis ybt-151 ... | 2014 | 24333130 |
| delivery of intrahemocoelic peptides for insect pest management. | the extensive use of chemical insecticides for insect pest management has resulted in insecticide resistance now being recorded in >500 species of insects and mites. although gut-active toxins such as those derived from bacillus thuringiensis (bt) have been successfully used for insect pest management, a diverse range of insect-specific insecticidal peptides remains an untapped resource for pest management efforts. these toxins act within the insect hemocoel (body cavity) and hence require a del ... | 2014 | 24331760 |
| up-regulated death-associated lim-only protein contributes to fitness costs of bacillus thuringiensis cry1ac resistance in helicoverpa armigera. | the evolution of bacillus thuringiensis (bt) resistance provides a useful pathway for the study of fitness trade-offs associated with stress adaptation. in a previous study, we used cdna-amplification fragment length polymorphism (cdna-alfp) analysis to identify differentially expressed genes (degs) in cry1ac-susceptible (96s) and -resistant (bt-r) helicoverpa armigera larvae. among these degs, a death-associated lim-only protein (hadalp) was identified. in the current study, the full-length cdn ... | 2014 | 24326206 |
| the glycosyltransferase involved in thurandacin biosynthesis catalyzes both o- and s-glycosylation. | the s-glycosyltransferase suns is a recently discovered enzyme that selectively catalyzes the conjugation of carbohydrates to the cysteine thiol of proteins. this study reports the discovery of a second s-glycosyltransferase, thus, and shows that thus catalyzes both s-glycosylation of the thiol of cysteine and o-glycosylation of the hydroxyl group of serine in peptide substrates. thus-catalyzed s-glycosylation is more efficient than o-glycosylation, and the enzyme demonstrates high tolerance wit ... | 2014 | 24325644 |
| coexpression of the silent cry2ab27 together with cry1 genes in bacillus thuringiensis subsp. aizawai sp41 leads to formation of amorphous crystal toxin and enhanced toxicity against helicoverpa armigera. | the unexpressed cry2ab27 gene of bacillus thuringiensis subsp. aizawai sp41 (sp41) consists of a single open reading frame (orf) of 1902bp encoding for 634 amino acid residues. the cry2ab27 gene appears to be silent due to the lack of promoter and terminator sequences. in this study we fused the cry2ab27 orf with the cry1ab promoter (500bp) and the terminator (300bp) in vector pht304-18z in order to drive the expression of cry2ab27 in both sp41 and an acrystaliferous, b. thuringiensis subsp. thu ... | 2014 | 24412546 |
| persistence and recycling of bioinsecticidal bacillus thuringiensis subsp. israelensis spores in contrasting environments: evidence from field monitoring and laboratory experiments. | sprays of commercial preparations of the bacterium bacillus thuringiensis subsp. israelensis are widely used for the control of mosquito larvae. despite an abundant literature on b. thuringiensis subsp. israelensis field efficiency on mosquito control, few studies have evaluated the fate of spores in the environment after treatments. in the present article, two complementary experiments were conducted to study the effect of different parameters on b. thuringiensis subsp. israelensis persistence ... | 2014 | 24402370 |
| hexamerin a novel protein associated with bacillus sphaericus resistance in culex quinquefasciatus. | bacterial insecticides like, bacillus sphaericus and bacillus thuringiensis serovar israelensis, have been used for the control of nuisance and vector mosquitoes for more than two decades. for many years, it was assumed that the use of microbial larvicides based on b. sphaericus would not lead to resistance in mosquitoes. however, recent reports have shown that b. sphaericus toxins are not free from this problem. therefore, the resistance of mosquito populations to be will seriously threaten the ... | 2014 | 24395693 |
| development of a high efficient "dual bt-plus" insecticide using a primary form of an entomopathogenic bacterium, xenorhabdus nematophila. | a phase variation has been reported in an entomopathogenic bacterium, xenorhabdus nematophila. compared with a wild-type primary form, a secondary form usually loses several physiological and biochemical characters. this study showed that the phase variation of x. nematophila caused a significant alteration in its immunosuppressive activity and subsequent entomopathogenicity. a secondary form of x. nematophila was detected in laboratory colonies and exhibited significant differences in dye absor ... | 2014 | 24394195 |
| improved insecticidal toxicity by fusing cry1ac of bacillus thuringiensis with av3 of anemonia viridis. | av3, a neurotoxin of anemonia viridis, is toxic to crustaceans and cockroaches but inactive in mammals. in the present study, av3 was expressed in escherichia coli origami b (de3) and purified by reversed-phase liquid chromatography. the purified av3 was injected into the hemocoel of helicoverpa armigera, rendering the worm paralyzed. then, av3 was expressed alone or fusion expressed with the cry1ac in acrystalliferous strain cry(-)b of bacillus thuringiensis. the shape of cry1ac was changed by ... | 2014 | 24375189 |
| genotoxic evaluation in oreochromis niloticus (fish: characidae) of recombinant spore-crystal complexes cry1ia, cry10aa and cry1ba6 from bacillus thuringiensis. | bioinsecticides from bacillus thuringiensis (bt) are widely used around the world in biological control against larval stages of many insect species. bt has been considered a biopesticide that is highly specific to different orders of insects, non-polluting and harmless to humans and other vertebrates, thus becoming a viable alternative for combating agricultural pests and insect vectors of diseases. the family of bt δ-endotoxins are crystal-protein inclusions showing toxicity to insects' midgut ... | 2014 | 24374720 |
| characterization of parasporin gene harboring indian isolates of bacillus thuringiensis. | bacillus thuringiensis (bt) is popularly known as insecticidal bacterium. however, non-insecticidal bt strains are more extensively available in natural environment than the insecticidal ones. parasporin (ps) is a collection of genealogically heterogeneous cry proteins synthesized in non-insecticidal isolates of bt. an important character generally related with ps proteins is their strong cytocidal activity preferentially on human cancer cells of various origins. identification and characterizat ... | 2014 | 28324389 |
| proposed measures of control management of the grape moth, lobesia botrana den and schiff (lepidoptera: tortricidae), in reference to infestation percentages, yield loss and economics of control in egypt. | this study aims to evaluate the efficacy of five measures; including the release of two strains of trichogramma, bacillus thuringiensis (b.t.). sweetened b.t. and the environmentally friend insecticide (tracer®), to manage the grape moth, lobesia botrana that infested the grape vines c.v. "thompson seedless " in egypt severely during the two successive years of 2011 and 2012. in concern to the release of the worldwide, trichogramma evanescens westwood., the mean total grape yield ranged from 8.0 ... | 2014 | 26084105 |
| a screening of five bacillus thuringiensis vip3a proteins for their activity against lepidopteran pests. | five bacillus thuringiensis vip3a proteins (vip3aa, vip3ab, vip3ad, vip3ae and vip3af) and their corresponding trypsin-activated toxins were tested for their toxicity against eight lepidopteran pests: agrotis ipsilon, helicoverpa armigera, mamestra brassicae, spodoptera exigua, spodoptera frugiperda, spodoptera littoralis, ostrinia nubilalis and lobesia botrana. toxicity was first tested at a high dose at 7 and 10 days. no major differences were found when comparing protoxins vs. trypsin-activat ... | 2014 | 24508583 |
| potency of insect-specific scorpion toxins on mosquito control using bacillus thuringiensis cry4aa. | two insect-specific scorpion toxins, bjαit and aahit were produced as alkali-soluble protein inclusions in escherichia coli. the inclusion bodies themselves exhibited no toxicity against culex pipiens larvae. however, coadministration with cry4aa toxin enhanced the mosquitocidal activity by 2-3 fold. insect-specific scorpion toxins can be good supplements for cry toxin-based bioinsecticides. | 2014 | 24508022 |
| fitness costs and stability of cry1ab resistance in sugarcane borer, diatraea saccharalis (f.). | the sugarcane borer, diatraea saccharalis (f.), is a major target species of transgenic corn expressing bacillus thuringiensis (bt) proteins in south america and the u.s. mid-south region. in this study, the fitness of seven insect genotypes of d. saccharalis were assayed on non-toxic diet, which included a cry1ab-susceptible strain (ss-2009), two cry1ab-resistant strains (rr-43a(bc), rr-l5b(bc)), and four f1 hybrids (f1-r43a(m)s(f), f1-r43a(f)s(m), f1-r5b(m)s(f), and f1-r5b(f)s(m)). the f1 hybr ... | 2014 | 24503242 |
| market forces and technological substitutes cause fluctuations in the value of bat pest-control services for cotton. | critics of the market-based, ecosystem services approach to biodiversity conservation worry that volatile market conditions and technological substitutes will diminish the value of ecosystem services and obviate the "economic benefits" arguments for conservation. to explore the effects of market forces and substitutes on service values, we assessed how the value of the pest-control services provided by mexican free-tailed bats (tadarida brasiliensis mexicana) to cotton production in the southwes ... | 2014 | 24498400 |
| sinr controls enterotoxin expression in bacillus thuringiensis biofilms. | the entomopathogen bacillus thuringiensis produces dense biofilms under various conditions. here, we report that the transition phase regulators spo0a, abrb and sinr control biofilm formation and swimming motility in b. thuringiensis, just as they control biofilm formation and swarming motility in the closely related saprophyte species b. subtilis. however, microarray analysis indicated that in b. thuringiensis, in contrast to b. subtilis, sinr does not control an eps operon involved in exopolys ... | 2014 | 24498128 |
| nondestructive determination of transgenic bacillus thuringiensis rice seeds (oryza sativa l.) using multispectral imaging and chemometric methods. | crop-to-crop transgene flow may affect the seed purity of non-transgenic rice varieties, resulting in unwanted biosafety consequences. the feasibility of a rapid and nondestructive determination of transgenic rice seeds from its non-transgenic counterparts was examined by using multispectral imaging system combined with chemometric data analysis. principal component analysis (pca), partial least squares discriminant analysis (plsda), least squares-support vector machines (ls-svm), and pca-back p ... | 2014 | 24491704 |
| coadministration of protoxin cry1ac from bacillus thuringiensis with metacestode extract confers protective immunity to murine cysticercosis. | the bacillus thuringiensis cry1ac protoxin (pcry1ac) is a promising mucosal immunogen and adjuvant that induces protective immunity against naegleria fowleri and malaria infection models. we determined whether pcry1ac acted as a protective adjuvant against infection with taenia crassiceps. balb/c mice were thrice i.p. immunized with (i) pcry1ac, (ii) metacestode extract, (iii) extract + pcry1ac or (iv) vehicle, challenged with metacestodes on day 26 and then sacrificed 35 days later. cysticerci ... | 2014 | 24484070 |
| draft genome sequence of bacillus thuringiensis strain brmgv02-jm63, a chitinolytic bacterium isolated from oil-contaminated mangrove soil in brazil. | here, we report the draft genome sequence and the automatic annotation of bacillus thuringiensis strain brmgv02-jm63. this genome comprises a set of genes involved in the metabolism of chitin and n-acetylglucosamine utilization, thus suggesting the possible role of this strain in the cycling of organic matter in mangrove soils. | 2014 | 24482524 |
| established a new double antibodies sandwich enzyme-linked immunosorbent assay for detecting bacillus thuringiensis (bt) cry1ab toxin based single-chain variable fragments from a naïve mouse phage displayed library. | scfvs are composed of the variable regions of the heavy and light chains via a short linker that maintain the specific antigen binding abilities of antibodies. in this study, we constructed a naïve mouse phage displayed library to generate scfvs against cry1ab toxin. after affinity panning, positive phage-scfvs were isolated, sequenced and characterized by elisa. the best binding ability scfv-g9 was expressed and purified. sds-page indicated that the relative molecular mass of scfv was estimated ... | 2014 | 24472345 |
| using resistant prey demonstrates that bt plants producing cry1ac, cry2ab, and cry1f have no negative effects on geocoris punctipes and orius insidiosus. | geocoris punctipes (say) and orius insidiosus (say) are generalist predators found in a wide range of crops, including cotton (gossypium hirsutum l.) and maize (zea mays l.), where they provide important biological control services by feeding on an array of pests, including eggs and small larvae of caterpillars. a high percentage of cotton and maize in the united states and several other countries are transgenic cultivars that produce one or more of the insecticidal cry proteins of bacillus thur ... | 2014 | 24472212 |
| target and nontarget effects of novel "triple-stacked" bt-transgenic cotton 1: canopy arthropod communities. | transgenic cotton varieties (bollgard ii) expressing two proteins (cry1ac and cry2ab) from bacillus thuringiensis (bt) have been widely adopted in australia to control larvae of helicoverpa. a triple-stacked bt-transgenic cotton producing cry1ac, cry2ab, and vip3a proteins (genuity bollgard iii) is being developed to reduce the chance that helicoverpa will develop resistance to the bt proteins. before its introduction, nontarget effects on the agro-ecosystem need to be evaluated under field cond ... | 2014 | 24472211 |
| impacts of bt rice expressing cry1c or cry2a protein on the performance of nontarget leafhopper, nephotettix cincticeps (hemiptera: cicadellidae), under laboratory and field conditions. | transgenic rice expressing bacillus thuringiensis berliner (bt) protein can effectively control target insects including stem borers and leaf folders. however, the potential effects of bt rice on nontarget organisms including nontarget herbivores have not been fully evaluated. in the current study, ecological fitness parameters of the nontarget herbivore, nephotettix cincticeps (uhler) (hemiptera: cicadellidae), fed on t1c-19 (cry1c) or t2a-1 (cry2a) rice were compared with non-bt rice (mh63) un ... | 2014 | 24472210 |
| genetic resistance to bacillus thuringiensis alters feeding behaviour in the cabbage looper, trichoplusia ni. | evolved resistance to xenobiotics and parasites is often associated with fitness costs when the selection pressure is absent. resistance to the widely used microbial insecticide bacillus thuringiensis (bt) has evolved in several insect species through the modification of insect midgut binding sites for bt toxins, and reports of costs associated with bt resistance are common. studies on the costs of bt-resistance restrict the insect to a single artificial diet or host-plant. however, it is well d ... | 2014 | 24465656 |
| bacillus thuringiensis subsp. kurstaki hd1 as a factory to synthesize alkali-labile chia74∆sp chitinase inclusions, cry crystals and spores for applied use. | the endochitinase chia74 is a soluble secreted enzyme produced by bacillus thuringiensis that synergizes the entomotoxigenecity of cry proteins that accumulate as intracellular crystalline inclusion during sporulation. the purpose of this study was to produce alkaline-soluble chia74∆sp inclusions in b. thuringiensis, and to determine its effect on cry crystal production, sporulation and toxicity to an important agronomical insect, manduca sexta. to this end we deleted the secretion signal peptid ... | 2014 | 24460864 |
| bacillus thuringiensis: a specific gamma-cyclodextrin producer strain. | an anaerobic microbial isolate bacillus species, designated b. thuringiensis gu-2, was isolated from soil as a specific γ-cyclodextrin (cd) producer strain in alkaline medium under anaerobic conditions. the optimum ph and temperature for bacterial growth and γ-cd production were estimated to be ph 8.5 and 37°c in the presence of 1.0% starch substrate, respectively. a high purity yield >95% of γ-cd from the total cd yield in the reaction mixture was obtained from starch that was supposed to be co ... | 2014 | 24456970 |
| activation of map kinase pathways in galleria mellonella infected with bacillus thuringiensis. | we followed changes in the level of phospho-map kinases in the greater wax moth galleria mellonella after infection with bacillus thuringiensis. we observed an enhanced level of phosphorylated p38 and jnk in fat bodies of the infected larvae. in hemocytes, injection of b. thuringiensis caused the highest increase in phospho-jnk, however, all pathways were activated after aseptic injection. we report that galleria mellonella larvae exposed to heat shock before infection showed an enhanced level o ... | 2014 | 24455757 |
| bacillus thuringiensis cry6a exhibits nematicidal activity to caenorhabditis elegans bre mutants and synergistic activity with cry5b to c. elegans. | the group of nematicidal crystal protein cry6a shares very low identity and exhibits different structure with cry5b, another well-studied group of nematicidal crystal protein produced by bacillus thuringiensis. in this study, we assayed the susceptibility of bre mutants (caenorhabditis elegans with resistance to cry5b) to cry6aa2 and examined the synergistic activity between cry6aa2 and cry5ba2. our results show that all bre mutants are susceptible to cry6aa2 on the lethal activity, growth inhib ... | 2014 | 24450432 |
| new bacillus thuringiensis toxin combinations for biological control of lepidopteran larvae. | cyt1aa from bacillus thuringiensis israelensis is known by its synergistical activity with b. thuringiensis and bacillus sphaericus toxins. it is able to improve dipteran specific toxins activity and can prevent or overcome larval resistance to those proteins. the objective of the current study was to investigate the possible improvement of larvicidal activity of b. thuringiensis kurstaki expressing heterogeneous proteins cyt1a and p20. cyt1a98 and p20 genes encoding the cytolytic protein (cyt1a ... | 2014 | 24444881 |
| insilico structural 3d modelling of novel cry1ib9 and cry3a toxins from local isolates of bacillus thuringiensis. | three-dimensional (3d) models for the 79.2 kda activated cry1ib9 and 77.4 kda activated cry3a δ-endotoxins from bacillus thuringiensis (bt) native isolates that are specifically toxic to coleopteran insect pests were constructed by utilizing homology modeling online tool. evidences presented here, based on the identification of structural equivalent residues of cry1ib9 and cry3a toxin through homology modelling indicate that, they share a common bt toxin tridimensional structure. the main differ ... | 2014 | 24426173 |
| development of a homologous expression system for and systematic site-directed mutagenesis analysis of thurincin h, a bacteriocin produced by bacillus thuringiensis sf361. | thurincin h is an antimicrobial peptide produced by bacillus thuringiensis sf361. with a helical back bone, the 31 amino acids of thurincin h form a hairpin structure maintained by four pairs of very unique sulfur-to-α-carbon thioether bonds. the production of thurincin h depends on a putative gene cluster containing 10 open reading frames. the gene cluster includes three tandem structural genes (thna1, thna2, and thna3) encoding three identical 40-amino-acid thurincin h prepeptides and seven ot ... | 2014 | 24682301 |
| detection and identification of transgenic elements by fluorescent-pcr-based capillary gel electrophoresis in genetically modified cotton and soybean. | a detection method for genetically modified foods is an essential regulatory requirement for many countries. the present study is aimed at developing a qualitative method for detection of genetically modified organisms by combining pcr methodology with capillary gel electrophoresis (pcr-cge) in a sequencing platform to detect bacillus thuringiensis (bt)-cotton (mon 531) and roundup ready (rr) soybean (gts 40-3-2). a sensitive duplex pcr-cge method was developed in which target dna sequences (35s ... | 2014 | 24672872 |
| lactonase-expressing lactobacillus plantarum nc8 attenuates the virulence factors of multiple drug resistant pseudomonas aeruginosa in co-culturing environment. | pseudomonas aeruginosa possesses an arcade of both cell-associated and extracellular cytotoxic virulence factors which are regulated by a multi-component quorum sensing system. many research studies report success of lactonase in combating the pathogenicity of p. aeruginosa but delivery of lactonase remains a challenge. the present study aims at developing a delivery vehicle for lactonase. lactobacillus plantarum nc8 was used as host for aiia (bacillus thuringiensis 4a3 lactonase gene) using psi ... | 2014 | 24671300 |
| uptake and transfer of a bt toxin by a lepidoptera to its eggs and effects on its offspring. | research on non-target effects of transgenic crop plants has focused primarily on bitrophic, tritrophic and indirect effects of entomotoxins from bacillus thuringiensis, but little work has considered intergenerational transfer of cry proteins. this work reports a lepidopteran (chlosyne lacinia) taking up a bt entomotoxin when exposed to sublethal or low concentrations, transferring the entomotoxin to eggs, and having adverse effects on the first filial generation (f1) offspring. two bioassays w ... | 2014 | 24747962 |
| multi-method approach for characterizing the interaction between fusarium verticillioides and bacillus thuringiensis subsp. kurstaki. | bacterial antagonists used as biocontrol agents represent part of an integrated management program to reduce pesticides in the environment. bacillus thuringiensis is considered a good alternative as a biocontrol agent for suppressing plant pathogens such as fusarium. in this study, we used microscopy, flow cytometry, indirect immunofluorescence, and high performance liquid chromatography to determine the interaction between b. thuringiensis subsp. kurstaki lfb-fiocruz (ccgb) 257 and f. verticill ... | 2014 | 24739804 |
| contributions of cellular and humoral immunity of galleria mellonella larvae in defence against oral infection by bacillus thuringiensis. | in this study the cellular and humoral immune reactions of the greater wax moth galleria mellonella have been investigated during bacterial infection caused by oral administration of bacillus thuringiensis. two different dose strengths were investigated to assess the contribution of immune parameters to induced bt resistance. low-dose (sublethal lc15) infection resulted in significantly elevated haemolymph phenoloxidase and lysozyme-like activity, enhanced phagocytic activity of haemocytes, and ... | 2014 | 24735783 |
| a novel recombinant baculovirus overexpressing a bacillus thuringiensis cry1ab toxin enhances insecticidal activity. | baculoviruses have been genetically modified to express foreign genes under powerful promoters in order to accelerate their speed of killing. in this study a truncated form of cry1ab gene derived from bacillus thuringinsis (bt) subsp. aegypti isolate bt7 was engineered into the genome of the baculovirus autographa californica multiple nuclearpolyhedrosis wild type virus, in place of the polyhedrin gene by using homologous recombination in spodoptera frugiperda (sf) cells between a transfer vecto ... | 2014 | 24735532 |
| mode of action and specificity of bacillus thuringiensis toxins in the control of caterpillars and stink bugs in soybean culture. | the bacterium bacillus thuringiensis (bt) produces delta-endotoxins that possess toxic properties and can be used as biopesticides, as well as a source of genes for the construction of transgenic plants resistant to insects. in brazil, the introduction of bt soybean with insecticidal properties to the velvetbean caterpillar, the main insect pest of soybean, has been seen a promising tool in the management of these agroecosystems. however, the increase in stink bug populations in this culture, in ... | 2014 | 24575310 |
| cellular responses in bacillus thuringiensis cs33 during bacteriophage btcs33 infection. | bacillus thuringiensis (bt) has been widely used for 50years as a biopesticide for controlling insect pests. however, bacteriophage infection can cause failures in 50%-80% of the batches during bt fermentation, resulting in severe losses. in the present work, the physiological and biochemical impacts of bt strain cs33 have been studied during bacteriophage infection. this study adopted a gel-based proteomics approach to probe the sequential changed proteins in phage-infected bt cells. to phage, ... | 2014 | 24565692 |
| draft genome sequence of highly nematicidal bacillus thuringiensis db27. | here, we report the genome sequence of nematicidal bacillus thuringiensis db27, which provides first insights into the genetic determinants of its pathogenicity to nematodes. the genome consists of a 5.7-mb chromosome and seven plasmids, three of which contain genes encoding nematicidal proteins. | 2014 | 24558243 |
| tradeoff between reproduction and resistance evolution to bt-toxin in helicoverpa armigera: regulated by vitellogenin gene expression. | evolution of resistance to insecticides usually has fitness tradeoffs associated with adaptation to the stress. the basic regulation mechanism of tradeoff between reproduction and resistance evolution to bacillus thuringiensis (bt) toxin in the cotton bollworm, helicoverpa armigera (ha), based on the vitellogenin (vg) gene expression was analyzed here. the full-length cdna of the vg gene havg (jx504706) was cloned and identified. havg has 5704 base pairs (bp) with an open reading frame (orf) of ... | 2014 | 24555504 |
| bacterial tubulin tubz-bt transitions between a two-stranded intermediate and a four-stranded filament upon gtp hydrolysis. | cytoskeletal filaments form diverse superstructures that are highly adapted for specific functions. the recently discovered tubz subfamily of tubulins is involved in type iii plasmid partitioning systems, facilitating faithful segregation of low copy-number plasmids during bacterial cell division. one such protein, tubz-bt, is found on the large pbtoxis plasmid in bacillus thuringiensis, and interacts via its extended c terminus with a dna adaptor protein tubr. here, we use cryo-electron microsc ... | 2014 | 24550513 |
| the ecological roles of bacillus thuringiensis within phyllosphere environments. | bacillus thuringiensis (bt) is one of the most used bio-control agents to control plant insects, but little is known about its effect on the microbial population and communities on plant leaves. with the culture dependent method, it has been observed that the dynamics of bt within the phyllosphere varied dependent on both the doses of bt sprayed on the leaves and the plant species, however, bt's population size kept stable at about 1000 cfu g(-1) after 15 d since inoculation. by comparing the ba ... | 2014 | 24534157 |
| control of diatraea saccharalis by the endophytic pantoea agglomerans 33.1 expressing cry1ac7. | despite the fact that bacillus thuringiensis (bt) is found in more than 90 % of the products used against insects, it has some difficulty reaching the internal regions where the larvae feed. to solve this problem, many genetically modified microorganisms that colonize the same pests have been developed. thus, the endophytic bacterium pantoea agglomerans (33.1), which has been recently described as a promising sugarcane growth promoter, was genetically modified with the pjtt vector (which carries ... | 2014 | 24531524 |