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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 ...201424402370
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 ...201424395693
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 ...201424394195
antibacterial activity of elephant garlic and its effect against u2os human osteosarcoma cells.the present study was designed to investigate the antibacterial function and pharmacological effect of elephant garlic (allium ampeloprasum var. ampeloprasum) on u2os human osteosarcoma cells.201324379966
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 ...201424375189
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 ...201424374720
pre-feeding of a glycolipid binding protein lec-8 from caenorhabditis elegans revealed enhanced tolerance to cry1ac toxin in helicoverpa armigera.crystal toxins from bacillus thuringiensis bind to glycolipids and glycoproteins using two different lectin domains in the toxin protein. our previous observations suggested that the sequestration of crystal toxin depends on the functional interaction of a toxin lectin with glycolipids. given the finding that competition of a galectin lec-8 with cry5b for binding to glycolipids resulting in reduced bt toxicity in nematode, it is interesting to explore the role of lec-8 in insects. here, we repor ...201224371572
molecular characterization of bacillus thuringiensis using rep-pcr.the genetic divergence of 65 strains of bacillus thuringiensis (bt) was determined using rep-pcr. based on the repetitive sequences the box primer was the most informative with 26 fragments, followed by eric (19) and rep (10), generating a total of 55 fragments. the dendogram shows that ten groups were formed when 45% was the average distance of the population: group 1 with 41,5% of the isolates, 33,8% of the isolates were distributed in other groups and 24,6% did not formed distinct group. 53,2 ...201324363981
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 ...201424355805
mechanism of killing of spores of bacillus anthracis in a high-temperature gas environment, and analysis of dna damage generated by various decontamination treatments of spores of bacillus anthracis, bacillus subtilis and bacillus thuringiensis.to determine how hydrated bacillus anthracis spores are killed in a high-temperature gas environment (htge), and how spores of several bacillus species including b. anthracis are killed by uv radiation, dry heat, wet heat and desiccation.201424344920
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 ...201424342232
bacillus thuringiensis poisoning related acute transverse myelitis. 201324340786
bacillus thuringiensis as a surrogate for bacillus anthracis in aerosol research.characterization of candidate surrogate spores prior to experimental use is critical to confirm that the surrogate characteristics are as closely similar as possible to those of the pathogenic agent of interest. this review compares the physical properties inherent to spores of bacillus anthracis (ba) and bacillus thuringiensis (bt) that impact their movement in air and interaction with surfaces, including size, shape, density, surface morphology, structure and hydrophobicity. also evaluated is ...201424338558
differential activity of autochthonous bacteria in controlling drought stress in native lavandula and salvia plants species under drought conditions in natural arid soil.the effectiveness of autochthonous plant growth-promoting rhizobacteria was studied in lavandula dentata and salvia officinalis growing in a natural arid mediterranean soil under drought conditions. these bacteria identified as bacillus megaterium (bm), enterobacter sp. (e), bacillus thuringiensis (bt), and bacillus sp. (bsp). each bacteria has different potential to meliorate water limitation and alleviating drought stress in these two plant species. b. thuringiensis promoted growth and drought ...201424337805
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 ...201424333130
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 ...201424331760
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 ...201424326206
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 ...201424325644
comprehensive analysis of gene expression profiles of the beet armyworm spodoptera exigua larvae challenged with bacillus thuringiensis vip3aa toxin.host-pathogen interactions result in complex relationship, many aspects of which are not completely understood. vip proteins, which are bacillus thuringensis (bt) insecticidal toxins produced during the vegetative stage, are selectively effective against specific insect pests. this new group of bt proteins represents an interesting alternative to the classical bt cry toxins because current data suggests that they do not share the same mode of action. we have designed and developed a genome-wide ...201324312604
cloning and analysis of a large plasmid pbmb165 from bacillus thuringiensis revealed a novel plasmid organization.in this study, we report a rapid cloning strategy for large native plasmids via a contig linkage map by bac libraries. using this method, we cloned a large plasmid pbmb165 from bacillus thuringiensis serovar tenebrionis strain ybt-1765. complete sequencing showed that pbmb165 is 77,627 bp long with a gc-content of 35.36%, and contains 103 open reading frames (orfs). sequence analysis and comparison reveals that pbmb165 represents a novel plasmid organization: it mainly consists of a pxo2-like re ...201324312580
purification, biochemical characterization and self-assembled structure of a fengycin-like antifungal peptide from bacillus thuringiensis strain sm1.an antifungal lipopeptide fengycin, producing strain sm1 was isolated from farm land soil sample and identified as bacillus thuringiensis strain sm1 by using 16s rdna analysis. fengycin detected in the culture extract was further purified using hplc and showed a molecular mass of 1492.8 da by maldi-tof-ms analysis. purified fengycin was allowed to construct their self-assembled structure onto a hydrophobic surface showing a clear improvement of antibacterial activity. in self-assembly, fengycin ...201324312083
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 ...201424310935
complete genome sequence of bacillus thuringiensis serovar israelensis strain hd-789.bacillus thuringiensis is an important microbial insecticide for controlling agricultural pests. we report the finished genome sequence of bacillus thuringiensis serovar israelensis strain hd-789, which contains genes encoding 7 parasporal crystals consisting of cry4aa3, cry4ba5 (2 genes), cry10aa3, cry11aa3, cry60ba3, and cry60aa3, plus 3 cyt toxin genes and 1 hemagglutinin gene.201324309743
complete genome of bacillus thuringiensis myophage spock.bacillus thuringiensis is a gram-positive, sporulating soil microbe with valuable pesticide-producing properties. the study of bacteriophages of b. thuringiensis could provide new biotechnological tools for the use of this bacterium. here, we present the complete annotated genome of spock, a myophage of b. thuringiensis, and describe its features.201324309729
complete genome of bacillus thuringiensis myophage bigbertha.bigbertha is a myophage of bacillus thuringiensis, a widely used biocontrol agent that is active against many insect pests of plants. here, we present the complete annotated genome of bigbertha. the genome shares 85.9% sequence identity with bacillus cereus phage b4.201324309723
domain wise docking analyses of the modular chitin binding protein cbp50 from bacillus thuringiensis serovar konkukian s4.this paper presents an in silico characterization of the chitin binding protein cbp50 from b. thuringiensis serovar konkukian s4 through homology modeling and molecular docking. the cbp50 has shown a modular structure containing an n-terminal cbm33 domain, two consecutive fibronectin-iii (fn-iii) like domains and a c-terminal cbm5 domain. the protein presented a unique modular structure which could not be modeled using ordinary procedures. so, domain wise modeling using modeller and docking anal ...201324307767
ingestibility, digestibility, and engineered biological control potential of flavobacterium hibernum, isolated from larval mosquito habitats.flavobacterium hibernum, isolated from larval habitats of the eastern tree hole mosquito, a. triseriatus, remained suspended in the larval feeding zone much longer (8 days) than other bacteria. autofluorescent protein markers were developed for the labeling of f. hibernum with a strong flavobacterial expression system. green fluorescent protein (gfp)-tagged f. hibernum cells were quickly consumed by larval mosquitoes at an ingestion rate of 9.5 × 10(4)/larva/h. the ingested f. hibernum cells wer ...201424296502
bacillus thuringiensis strain 199 can induce systemic resistance in tomato against fusarium wilt.the research work was performed to investigate the potential of bacillus thuringiensis strain 199 to induce systemic resistance in tomato against fusarium wilt. roots of two-week-old seedlings of tomato plants were primed with bacterial strain. after 10 days of transplantation, some pots of tomato seedlings were provided with inoculum of fusarium oxysporum lycopersici according to experimental design to induce disease. after 15 days of incubation period, plants challenged with f. oxysporum lycop ...201324294498
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).201424293325
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 ...201424291630
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 ...201424290895
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 ...201424287693
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. ...201424286860
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 ...201424286660
functional characterizations of residues arg-158 and tyr-170 of the mosquito-larvicidal bacillus thuringiensis cry4ba.the insecticidal activity of bacillus thuringiensis (bt) cry toxins involves toxin stabilization, oligomerization, passage across the peritrophic membrane (pm), binding to midgut receptors and pore-formation. the residues arg-158 and tyr-170 have been shown to be crucial for the toxicity of bt cry4ba. we characterized the biological function of these residues. in mosquito larvae, the mutants r158a/e/q (r158) could hardly penetrate the pm due to a significantly reduced ability to alter pm permeab ...024286331
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 ...201424285088
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 ...201424275062
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 ...201424269376
prohibitin, an essential protein for colorado potato beetle larval viability, is relevant to bacillus thuringiensis cry3aa toxicity.bacillus thuringienesis (bt) cry toxins constitute the most extensively used environmentally safe biopesticide and their mode of action relies on the interaction of the toxins with membrane proteins in the midgut of susceptible insects that mediate toxicity and insect specificity. therefore, identification of bt cry toxin interacting proteins in the midgut of target insects and understanding their role in toxicity is of great interest to exploit their insecticidal action. using ligand blot, we d ...201324267691
plant defenses: chlorogenic acid and polyphenol oxidase enhance toxicity ofbacillus thuringiensis subsp.kurstaki toheliothis zea.two chemicals implicated in resistance of the tomato plant, chlorogenic acid and polyphenol oxidase, are known to form orthoquinones in damaged plant tissue. orthoquinones have been reported to alkylate -nh2 and -sh groups of proteins and amino acids, altering solubility, digestibility, and, for some pathogenic viruses, infectivity. here we explore effects of quinone alkylation on toxicity of an important microbial insecticide,bacillus thuringiensis subsp.kurstaki (btk), to larvalheliothis zea. ...199124258447
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 ...201424252542
efficacy of genetically modified bt toxins alone and in combinations against pink bollworm resistant to cry1ac and cry2ab.evolution of resistance in pests threatens the long-term efficacy of insecticidal proteins from bacillus thuringiensis (bt) used in sprays and transgenic crops. previous work showed that genetically modified bt toxins cry1abmod and cry1acmod effectively countered resistance to native bt toxins cry1ab and cry1ac in some pests, including pink bollworm (pectinophora gossypiella). here we report that cry1abmod and cry1acmod were also effective against a laboratory-selected strain of pink bollworm re ...201324244692
isolation and characterization of a novel native bacillus thuringiensis strain brc-hzm2 capable of degrading chlorpyrifos.studies were carried out to isolate chlorpyrifos degrading bacillus thuringiensis (bt) strains from chlorpyrifos-contaminated samples. six bt strains (isolation rate 2.7%) were isolated by modified sodium acetate antibiotic heat treatment, and one novel strain (brc-hzm2) was selected for further analysis. phenotype and phylogeny analysis of this strain was conducted on the basis of biochemical reactions, antibiotic sensitivity, 16s rrna genes, plasmid profile, insecticidal crystal protein profil ...201524243520
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 ...201424237606
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 ...201424233057
in silico modeling and functional interpretations of cry1ab15 toxin from bacillus thuringiensis btb-hm-16.the theoretical homology based structural model of cry1ab15 δ-endotoxin produced by bacillus thuringiensis btb-hm-16 was predicted using the cry1aa template (resolution 2.25 å). the cry1ab15 resembles the template structure by sharing a common three-domain extending conformation structure responsible for pore-forming and specificity determination. the novel structural differences found are the presence of β0 and α3, and the absence of α7b, β1a, α10a, α10b, β12, and α11a while α9 is located spati ...201324228249
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 ...201424225445
applying an integrated refuge to manage western corn rootworm (coleoptera: chrysomelidae): effects on survival, fitness, and selection pressure.the refuge strategy can delay resistance of insect pests to transgenic maize producing toxins from bacillus thuringiensis (bt). this is important for the western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), because of its history of adaptation to several management practices. a 2-yr study across four locations was conducted to measure the effects of integrated refuge (i.e., blended refuge) on western corn rootworm survival to adulthood, fitness characteristi ...201324224265
effect of bt maize and soil insecticides on yield, injury, and rootworm survival: implications for resistance management.a 2-yr field experiment was conducted to determine the effects on diabrotica spp. (coleoptera: chrysomelidae) of an insecticidal seed treatment (poncho 1250, (ai)/clothianidin) and a granular insecticide (aztec 2.1g, (ai)/tebupirimphos and cyfluthrin) alone and in combination with maize producing the insectidical toxin cry3bb1 derived from the bacterium bacillus thuringiensis (bt). yields for bt maize plots were significantly greater than for non-bt maize; however, insecticides did not significa ...201324224233
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 ...201424216503
expression profile and regulation of spore and parasporal crystal formation-associated genes in bacillus thuringiensis.bacillus thuringiensis, a gram-positive endospore-forming bacterium, is characterized by the formation of parasporal crystals consisting of insecticidal crystal proteins (icps) during sporulation. we reveal gene expression profiles and regulatory mechanisms associated with spore and parasporal crystal formation based on transcriptomics and proteomics data of b. thuringiensis strain ct-43. during sporulation, five icp genes encoded by ct-43 were specifically transcribed; moreover, most of the spo ...201324215520
laboratory tests on the efficacy of vbc60035, a combined larvicidal formulation of bacillus thuringiensis israelensis (strain am65-52) and bacillus sphaericus (strain 2362) against aedes albopictus in simulated catch basins.catch basins are a common breeding site for mosquito larvae in urban areas. the arrival in spain of the asian tiger mosquito, aedes albopictus, has turned catch basins into a challenging public health issue in some areas such as the baix llobregat region, where more than 135,000 units are treated per year in a large-scale application program. although biorational larvicides are used, modern formulations providing longer efficacy periods could lead to manpower savings. laboratory indoor trials ar ...201324199503
transformation of liquidambar styraciflua using agrobacterium tumefaciens.we describe the molecular transformation of liquidambar styraciflua using agrobacterium tumefaciens. a binary ti-plasmid vector containing a chimeric neomycin phosphotransferagene which confers resistance to kanamycin and either a chimeric bacillus thuringiensis toxin gene, a chimeric e. coli β-glucuronida(gus), or a chimeric tobacco anionic peroxidase gene was introduced into sweetgum by co-cultivation with agrobacterium tumefaciens. sweetgum shoots regenerated in the presence of kanamycin were ...199324197252
receptors and lethal effect of bacillus thuringiensis insecticidal crystal proteins to the anticarsia gemmatalis (lepidoptera, noctuidae).bioassays with insecticidal crystal proteins (icps) from bacillus thuringiensis have demonstrated that cry1aa, cry1ac, and cry1ba are the most active toxins on larvae of the anticarsia gemmatalis. the toxins cry1da and cry1ea are less toxic, and toxins cry2aa are not active. binding of these icps to midgut sections of the a. gemmatalis larvae was studied using streptavidin-mediated detection. the observed staining patterns showed that cry1aa and cry1ac bound to the brush border throughout the wh ...201324195006
production of virus resistant and insect tolerant transgenic tobacco plants.the cucumber mosaic virus coat protein (cmv-cp) gene and a modified bacillus thuringiensis δ-endotoxin (bt toxin) gene were cloned into plant expression vector pe3. tobacco (nicotiana tabacum cv. g28) leaf discs were transformed with agrobacterium tumefaciens a12 carrying recombinant pe14. transgenic r0 and r1 tobacco plants expressing cmv-cp and bt toxin genes were protected from cmv infection as well as feeding damage of manduca sexta (tobacco hornworm) larvae. these results demonstrate that i ...199424192882
potential of sugarcane bagasse (agro-industrial waste) for the production of bacillus thuringiensis israelensis.sugarcane bagasse is a renewable resource that can be used to produce biopesticide for the control of mosquito vectors. in the present study, we demonstrated that cane processed bagasse could be used to produce bacillus thuringiensis serovar israelensis (bti) for control of mosquito vectors viz: culex quinquefasciatus, anopheles stephensi and aedes aegypti. biochemical studies indicated that the bti spore/crystal toxins produced from the test culture medium (bagasse, bg + soybean, sb) are higher ...201324189680
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 ...201424189038
investigating the genetics of bti resistance using mrna tag sequencing: application on laboratory strains and natural populations of the dengue vector aedes aegypti.mosquito control is often the main method used to reduce mosquito-transmitted diseases. in order to investigate the genetic basis of resistance to the bio-insecticide bacillus thuringiensis subsp. israelensis (bti), we used information on polymorphism obtained from cdna tag sequences from pooled larvae of laboratory bti-resistant and susceptible aedes aegypti mosquito strains to identify and analyse 1520 single nucleotide polymorphisms (snps). of the 372 snps tested, 99.2% were validated using d ...201324187584
agrobacterium tumefaciens-mediated transformation of broccoli (brassica oleracea var. italica) and cabbage (b. oleracea var. capitata).transgenic broccoli (brassica oleracea var. italica) was produced by two agrobacterium tumefaciens-mediated transformation methods. one used flowering stalk explants from mature plants; the other used hypocotyl and petiole explants from in vitro-grown seedlings. several hundred transformants containing a bacillus thuringiensis ∂-endotoxin gene (cryia(c)-type) and the neomycin phosphotransferase gene were recovered. rooted transformants were obtained in as little as 3 months using seedling explan ...199524185794
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 ...201424185745
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 ...201424173811
immunostimulation by poly-β hydroxybutyrate-hydroxyvalerate (phb-hv) from bacillus thuringiensis in oreochromis mossambicus.the present study was designed to test the immunostimulatory efficacy of poly-β hydroxybutyrate-hydroxyvalerate (phb-hv) extracted from bacillus thuringiensis b.t.a102 on the immune system of oreochromis mossambicus. fish were fed with 0%, 1%, 3% or 5% phb-hv supplemented feed and were bled at regular intervals of 5 days. the specific immune response was measured in terms of antibody response to sheep red blood cells, the nonspecific immune mechanisms were analysed in terms of serum lysozyme act ...201424161774
a bumblebee (bombus ignitus) venom serine protease inhibitor that acts as a microbial serine protease inhibitor.serine protease inhibitors from bumblebee venom have been shown to block plasmin activity. in this study, we identified the protein bivspi from the venom of bombus ignitus to be a serine protease inhibitor and an antimicrobial factor. bivspi is a 55-amino acid mature peptide with ten conserved cysteine residues and a p1 methionine residue. bivspi is expressed in the venom gland and also found in the venom as an 8-kda peptide. recombinant bivspi that was expressed in baculovirus-infected insect c ...201424158004
green synthesis of silver nanoparticles, their characterization, application and antibacterial activity.our research focused on the production, characterization and application of silver nanoparticles (agnps), which can be utilized in biomedical research and environmental cleaning applications. we used an environmentally friendly extracellular biosynthetic technique for the production of the agnps. the reducing agents used to produce the nanoparticles were from aqueous extracts made from the leaves of various plants. synthesis of colloidal agnps was monitored by uv-visible spectroscopy. the uv-vis ...201324157517
cry1ac protoxin from bacillus thuringiensis promotes macrophage activation by upregulating cd80 and cd86 and by inducing il-6, mcp-1 and tnf-α cytokines.bacillus thuringiensis cry1ac protoxin (pcry1ac) is a promising mucosal adjuvant, but its action mechanism is unknown. we examined in vivo whether pcry1ac promotes the activation of macrophages in the peritoneum, spleen and mesenteric lymph nodes or in the lungs and bronchoalveolar lavage after intraperitoneal or intranasal pcry1ac administration, respectively, in balb/c mice. pcry1ac upregulated the costimulatory molecules cd80 and cd86 in these macrophages, but with distinct kinetics. in vitro ...201324157331
structural analysis and molecular dynamics simulations of novel δ-endotoxin cry1id from bacillus thuringiensis to pave the way for development of novel fusion proteins against insect pests of crops.the theoretical three-dimensional structure of a novel δ-endotoxin cry1id (81 kda) belonging to cry1i class, toxic to many of the lepidopteran pests has been investigated through comparative modeling. molecular dynamics (md) simulations was carried out to characterize its structural and dynamical features at 10 ns in explicit solvent using the gromacs version 4.5.4. finally the simulated model was validated by the saves, what if, metamqap, proq, modfold and molprobity servers. despite low sequen ...201324154610
dissipation of insecticidal cry1ac protein and its toxicity to nontarget aquatic organisms.the widespread cultivation of bacillus thuringiensis crops has raised public concerns on their risk to nontarget organisms. persistence of cry1ac protein in soil, sediment and water and its toxicity to nontarget aquatic organisms were determined. the dissipation of cry1ac toxin was well described using first order kinetics, with the half-lives (dt50) ranging from 0.8 to 3.2, 2.1 to 7.6 and 11.0 to 15.8 d in soil, sediment and water, respectively. microbial degradation played a key role in the di ...201324151928
mtx toxins from lysinibacillus sphaericus enhance mosquitocidal cry-toxin activity and suppress cry-resistance in culex quinquefasciatus.the interaction of mtx toxins from lysinibacillus sphaericus (formerly bacillus sphaericus) with bacillus thuringiensis subsp. israelensis cry toxins and the influence of such interactions on cry-resistance were evaluated in susceptible and cry-resistant culex quinquefasciatus larvae. mtx-1 and mtx-2 were observed to be active against both susceptible and resistant mosquitoes; however varying levels of cross-resistance toward mtx toxins were observed in the resistant mosquitoes. a 1:1 mixture of ...201324144574
an ldla domain-containing c-type lectin is involved in the innate immunity of eriocheir sinensis.c-type lectins (ctls) have crucial functions in recognizing and eliminating pathogens in innate immunity. this study identified a novel low-density lipoprotein receptor class a (ldla) domain-containing ctl, designated as esctldcp, from the chinese mitten crab eriocheir sinensis. the esctldcp cdna is 1258 bp long, with a 975 bp open reading frame that encodes a 324-amino acid protein. esctldcp contains a signal peptide, an ldla, and a single c-type lectin-like domain. esctldcp was only expressed ...201424140432
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 ...201424136625
a 104 kda aedes aegypti aminopeptidase n is a putative receptor for the cry11aa toxin from bacillus thuringiensis subsp. israelensis.the cry11aa protein produced in bacillus thuringiensis subsp. israelensis, a bacterial strain used worldwide for the control of aedes aegypti larvae, binds midgut brush border membrane vesicles (bbmv) with an apparent k(d) of 29.8 nm. previously an aminopeptidase n (apn), named aaeapn2, was identified as a putative cry11aa toxin binding protein by pull-down assays using biotinylated cry11aa toxin (chen et al., 2009. insect biochem. mol. biol. 39, 688-696). here we show this protein localizes to ...201324128608
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.201424124030
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.201424124020
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 ...201424123206
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 ...201424121643
unlinked genetic loci control the reduced transcription of aminopeptidase n 1 and 3 in the european corn borer and determine tolerance to bacillus thuringiensis cry1ab toxin.transgenic expression of bacillus thuringiensis (bt) crystalline (cry) toxins by crop plants result in reduced insect feeding damage, but sustainability is threatened by the development of resistance traits in target insect populations. we investigated bt toxin resistance trait in a laboratory colony of the european corn borer, ostrinia nubilalis, selected for increased survival when exposed to cry1ab and correlated survival on cry1ab toxin with a constitutive ∼146.2 ± 17.3-fold reduction in mid ...201324121099
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 ...201424120626
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 ...201424120447
biosorption of heavy metals by bacillus thuringiensis strain osm29 originating from industrial effluent contaminated north indian soil.the study was navigated to examine the metal biosorbing ability of bacterial strain osm29 recovered from rhizosphere of cauliflower grown in soil irrigated consistently with industrial effluents. the metal tolerant bacterial strain osm29 was identified as bacillus thuringiensis following 16s rrna gene sequence analysis. in the presence of the varying concentrations (25-150 mgl(-1)) of heavy metals, such as cadmium, chromium, copper, lead and nickel, the b. thuringiensis strain osm29 showed an ob ...201324115905
draft genome sequence of bacillus thuringiensis var. thuringiensis strain t01-328, a brazilian isolate that produces a soluble pesticide protein, cry1ia.bacillus thuringiensis var. thuringiensis strain t01-328, isolated from cubatão county (são paulo state, brazil), produces a soluble pesticide protein, cry1ia, during vegetative growth. here, we report the 7.089-mbp draft genome sequence, composed of a 5.5-mb chromosome and 14 plasmids, which is the largest b. thuringiensis genome sequenced to date.201324115545
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 ...201424114385
oligomerization is a key step in cyt1aa membrane insertion and toxicity but not necessary to synergize cry11aa toxicity in aedes aegypti larvae.bacillus thuringiensis produces insecticidal cry and cyt proteins that are toxic to different insect orders. in addition, cyt toxins also display haemolytic activity. both toxins are pore-forming proteins that form oligomeric structures that insert into the target membrane to lyse cells. cyt toxins play an important role in mosquitocidal activity since they synergize cry toxins and are able to overcome resistance to cry toxins. cry and cyt toxins interact by specific epitopes, and this interacti ...201324112611
the effects of bacillus thuringiensis cry6a on the survival, growth, reproduction, locomotion, and behavioral response of caenorhabditis elegans.several families of crystal proteins from bacillus thuringiensis exhibit nematicidal activity. cry5b protein, a pore-forming toxin, has been intensively studied yielding many insights into the mode of action of crystal protein at molecular level and pathogenesis of pore-forming toxins. however, little attention was paid to cry6a, another representative nematicidal crystal protein. cry6a shares very low homology with cry5b at amino acid sequence and probably acts in a distinct pathway from cry5b ...201324100681
do biopesticides affect the demographic traits of a parasitoid wasp and its biocontrol services through sublethal effects?pesticide risk assessments are usually based on short-term acute toxicity tests, while longer-term population dynamic related traits, critical to the success of biological control and integrated pest management (ipm) programs, are often overlooked. this is increasingly important with respect to new biopesticides that frequently cause no short-term acute effects, but that can induce multiple physiological and behavioral sublethal effects, leading to a decrease in population growth and ecosystem s ...201324098793
sequence-based analysis of the intestinal microbiota of sows and their offspring fed genetically modified maize expressing a truncated form of bacillus thuringiensis cry1ab protein (bt maize).the aim was to investigate transgenerational effects of feeding genetically modified (gm) maize expressing a truncated form of bacillus thuringiensis cry1ab protein (bt maize) to sows and their offspring on maternal and offspring intestinal microbiota. sows were assigned to either non-gm or gm maize dietary treatments during gestation and lactation. at weaning, offspring were assigned within sow treatment to non-gm or gm maize diets for 115 days, as follows: (i) non-gm maize-fed sow/non-gm maize ...201324096421
larvicidal efficacy of catharanthus roseus linn. (family: apocynaceae) leaf extract and bacterial insecticide bacillus thuringiensis against anopheles stephensi liston.to explore the larvicidal activity of catharanthus roseus (c. roseus) leaf extract and bacillus thuringiensis (b. thuringiensis) against the malarial vector anopheles stephensi (an. stephensi), when being used alone or together.201324083578
a rapid knockdown effect of penicillium citrinum for control of the mosquito culex quinquefasciatus in thailand.twenty local isolates of entomopathogenic fungi were determined for control of the larvae and adults of culex quinquefasciatus. in a laboratory experiment, a penicillium sp. cm-010 caused 100% mortality of third-instar larvae within 2 h using a conidial suspension of 1 × 10⁶ conidia ml⁻¹. its lc₅₀ was 3 × 10⁵ conidia ml⁻¹, and the lethal time (lt₅₀) was 1.06 h. cloning and sequencing of its internal transcribed spacer region indicated that this penicillium species is penicillium citrinum (100% i ...201424078109
insecticidal activity of bacillus thuringiensis cry1bh1 against ostrinia nubilalis (hubner) (lepidoptera: crambidae) and other lepidopteran pests.bacillus thuringiensis is an important source of insect resistance traits in commercial crops. in an effort to prolong b. thuringiensis trait durability, insect resistance management programs often include combinations of insecticidal proteins that are not cross resistant or have demonstrable differences in their site of action as a means to mitigate the development of resistant insect populations. in this report, we describe the activity spectrum of a novel b. thuringiensis cry protein, cry1bh1 ...201324077715
antimicrobial activity of a honeybee (apis cerana) venom kazal-type serine protease inhibitor.insect-derived kazal-type serine protease inhibitors exhibit thrombin, elastase, plasmin, proteinase k, or subtilisin a inhibition activity, but so far, no functional roles for bee-derived kazal-type serine protease inhibitors have been identified. in this study, a bee (apis cerana) venom kazal-type serine protease inhibitor (acktspi) that acts as a microbial serine protease inhibitor was identified. acktspi contained a single kazal domain that displayed six conserved cysteine residues and a p1 ...201324076031
use of silkworms to evaluate the pathogenicity of bacteria attached to cedar pollen.injection of a japanese cedar pollen suspension into silkworm hemolymph kills the silkworms. a certain species of bacteria proliferated in the hemolymph of the dead silkworms. a 16s rdna analysis demonstrated that the proliferating bacteria were bacillus cereus, bacillus thuringiensis, bacillus weihenstephanensis, and bacillus amyloliquefaciens. among them, b. cereus, b. thuringiensis, and b. weihenstephanensis exhibited hemolysis against sheep red blood cells and were lethal to mice. a culture ...201324071577
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 ...201424068502
[expression optimization and characterization of tenebrio molitor antimicrobiol peptides tmamp1m in escherichia coli].to improve the expression level of tmamp1m gene from tenebrio molitor in escherichia coli, we studied the effects of expression level and activity of the fusion protein his-tmamp1m by conditions, such as culture temperature, inducing time and the final concentration of inductor isopropyl beta-d-thiogalactopyranoside (iptg). we analyzed the optimum expression conditions by tricine-sds-page electrophoresis, meanwhile, detected its antibacterial activity by using agarose cavity diffusion method. th ...201324063242
pcr detection of cytk gene in bacillus cereus group strains isolated from food samples.a method for detection of the cytotoxin k cytk structural gene and its active promoter preceded by the plcr-binding box, controlling the expression level of this enterotoxin, was developed. the method was applied for the purpose of the analysis of 47 bacterial strains belonging to the bacillus cereus group isolated from different food products. it was found that the majority of the analyzed strains carried the fully functional cytk gene with its plcr regulated promoter. the cytk gene was not det ...201324060693
new insights into the binding and catalytic mechanisms of bacillus thuringiensis lactonase: insights into b. thuringiensis aiia mechanism.the lactonase enzyme (aiia) produced by bacillus thuringiensis serves to degrade autoinducer-1 (ai-1) signaling molecules in what is an evolved mechanism by which to compete with other bacteria. bioassays have been previously performed to determine whether the ai-1 aliphatic tail lengths have any effect on aiia's bioactivity, however, data to date are conflicting. additionally, specific residue contributions to the catalytic activity of aiia provide for some interesting questions. for example, i ...201324058683
rna interference of cadherin gene expression in spodoptera exigua reveals its significance as a specific bt target.cadherin is a calcium-dependent cell surface molecule and has been proposed to be a target molecule of bacillus thuringiensis cry proteins. based on a partial cadherin gene obtained from 454 pyrosequencing transcripts of the fifth instar spodoptera exigua midgut, a full open reading frame of cadherin gene (secad1) was cloned. its predicted amino acid sequence encodes extracellular 9 cadherin repeats, a transmembrane, and intracellular domain. secad1 gene was expressed in all developmental stages ...201324055650
pretreatment of spent mushroom substrate for enhancing the conversion of fermentable sugar.to develop a cost-effective biopesticide, spent mushroom substrate (sms) extract was studied as a potential carbon source for cultivating bacillus thuringiensis (bt). several pretreatments were compared to determine the optimal method for degrading cellulose to produce reducing sugars, including dilute sulfuric acid (0.5-2.0% v/v, 50-121°c, 1h), sodium hydroxide (0.5-2% w/v, 50-121°c, 1h), calcium hydroxide (0.2-4% w/v, 50-121°c, 1h), and hot water (50-121°c, 1h). pretreatment was followed by st ...201324047726
characterization and regulation of bacillus thuringiensis cry toxin binding aminopeptidases n (apns) from non-gut visceral tissues, malpighian tubule and salivary gland: comparison with midgut-specific apn in the moth achaea janata.bacillus thuringiensis (bt) crystal proteins (cry) bind to aminopeptidase n (apn) receptors on insect midgut membrane leading to pore formation and subsequent death. however, evolution of insect resistance to bt toxins threatens their long-term application. therefore, search for new targets which could function as cry toxin receptors is an immediate mandate. in the present study, two full-length apn cdnas were cloned from malpighian tubule and salivary gland tissues of the moth, achaea janata. b ...201324045122
isolation of an orally active insecticidal toxin from the venom of an australian tarantula.many insect pests have developed resistance to existing chemical insecticides and consequently there is much interest in the development of new insecticidal compounds with novel modes of action. although spiders have deployed insecticidal toxins in their venoms for over 250 million years, there is no evolutionary selection pressure on these toxins to possess oral activity since they are injected into prey and predators via a hypodermic needle-like fang. thus, it has been assumed that spider-veno ...201324039872
combined effect of microbial and chemical control agents on subterranean termites.termite mortality was measured when fungi were combined with bacteria or a chemical termiticide to determine whether a synergistic effect occurred. the fungus beauveria bassiana was combined with the non-repellant chemical termiticide imidacloprid. of the three b. bassiana strains tested one, b. bassiana atcc 90519, was sufficiently pathogenic on its own that the advantage of a supplementary chemical treatment was marginal. the mortality caused by another fungal strain, b. bassiana atcc 26037, w ...201324037651
monitoring resistance to bacillus thuringiensis subsp. israelensis in the field by performing bioassays with each cry toxin separately.bacillus thuringiensis subsp. israelensis (bti) is increasingly used worldwide for mosquito control and is the only larvicide used in the french rhône-alpes region since decades. the artificial selection of mosquitoes with field-persistent bti collected in breeding sites from this region led to a moderate level of resistance to bti, but to relatively high levels of resistance to individual bti cry toxins. based on this observation, we developed a bioassay procedure using each bti cry toxin separ ...024037105
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