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bioconversion of crude glycerol to polyhydroxyalkanoate by bacillus thuringiensis under non-limiting nitrogen conditions.glycerol has emerged as a cheap waste material due to blooming biodiesel manufacturing units worldwide. the need is to exploit the crude glycerol (cg) to produce useful products such as polyhydroxyalkanoate (pha). bacillus thuringiensis egu45 was found to produce 1.5-3.5 gp ha l(-1) from feed containing 1-10% cg (vv(-1)) and nutrient broth (nb, 125 ml) without any acclimatization. b. thuringiensis egu45 could produce pha at the rate of 1.54-1.83 g l(-1), from 1% cg (vv(-1)) on media having high ...201525840150
fulminant phlegmonitis of the esophagus, stomach, and duodenum due to bacillus thuringiensis.we report a case of phlegmonitis of the esophagus, stomach, and duodenum in patient in an immunocompromised state. culture of gastric juice and blood yielded bacillus thuringiensis. this case showed that even low-virulence bacilli can cause lethal gastrointestinal phlegmonous gastritis in conditions of immunodeficiency.201525834344
the impact of secondary pests on bacillus thuringiensis (bt) crops.the intensification of agriculture and the development of synthetic insecticides enabled worldwide grain production to more than double in the last third of the 20th century. however, the heavy dependence and, in some cases, overuse of insecticides has been responsible for negative environmental and ecological impacts across the globe, such as a reduction in biodiversity, insect resistance to insecticides, negative effects on nontarget species (e.g. natural enemies) and the development of second ...201525832330
the fate and transport of the cry1ab protein in an agricultural field and laboratory aquatic microcosms.genetically engineered crops expressing insecticidal crystalline proteins derived from bacillus thuringiensis (bt), were commercialized almost two decades ago as a means to manage agricultural pests. the bt proteins are highly specific and only lethal upon ingestion, limiting the scope of toxicity to target insects. however, concern of exposure to non-target organisms and negative public perceptions regarding bt crops has caused controversy surrounding their use. the objective of this research w ...201525828252
spatial soil heterogeneity has a greater effect on symbiotic arbuscular mycorrhizal fungal communities and plant growth than genetic modification with bacillus thuringiensis toxin genes.maize, genetically modified with the insect toxin genes of bacillus thuringiensis (bt), is widely cultivated, yet its impacts on soil organisms are poorly understood. arbuscular mycorrhizal fungi (amf) form symbiotic associations with plant roots and may be uniquely sensitive to genetic changes within a plant host. in this field study, the effects of nine different lines of bt maize and their corresponding non-bt parental isolines were evaluated on amf colonization and community diversity in pla ...201525827202
reconstitution of a prokaryotic minus end-tracking system using tubrc centromeric complexes and tubulin-like protein tubz filaments.segregation of dna is a fundamental process during cell division. the mechanism of prokaryotic dna segregation is largely unknown, but several low-copy-number plasmids encode cytomotive filament systems of the actin type and tubulin type important for plasmid inheritance. of these cytomotive filaments, only actin-like systems are mechanistically well characterized. in contrast, the mechanism by which filaments of tubulin-like tubz protein mediate dna motility is unknown. to understand polymer-dr ...201525825718
identification and characterization of a new alkaline thermolysin-like protease, btstlp1, from bacillus thuringiensis serovar sichuansis strain mc28.thermolysin and its homologs are a group of metalloproteases that have been widely used in both therapeutic and biotechnological applications. we here report the identification and characterization of a novel thermolysin-like protease, btstlp1, from insect pathogen bacillus thuringiensis serovar sichuansis strain mc28. btstlp1 is extracellularly produced in bacillus subtilis, and the active protein was purified via successive chromatographic steps. the mature form of btstlp1 has a molecule mass ...201525824434
are nematodes a missing link in the confounded ecology of the entomopathogen bacillus thuringiensis?bacillus thuringiensis, which is well known as an entomopathogen, has been accepted by the public as a safe bioinsecticide. the natural ecology of this bacterium has never been particularly clear, with views ranging from it being an obligate pathogen to an opportunist pathogen that can otherwise exist as a soil saprophyte or a plant endophyte. this confusion has recently led to it being considered as an environmental pathogen that has evolved to occupy a diverse set of environmental niches in wh ...201525818004
molecular detection and sensitivity to antibiotics and bacteriocins of pathogens isolated from bovine mastitis in family dairy herds of central mexico.thirty-two farms (n = 535 cows) located in the state of guanajuato, mexico, were sampled. pathogens from bovine subclinical mastitis (scm) and clinical mastitis (clm) were identified by 16s rdna and the sensitivity to both antibiotics and bacteriocins of bacillus thuringiensis was tested. forty-six milk samples were selected for their positive california mastitis test (cmt) (≥3) and any abnormality in the udder or milk. the frequency of scm and clm was 39.1% and 9.3%, respectively. averages for ...201525815326
autochthonous arbuscular mycorrhizal fungi and bacillus thuringiensis from a degraded mediterranean area can be used to improve physiological traits and performance of a plant of agronomic interest under drought conditions.studies have shown that some microorganisms autochthonous from stressful environments are beneficial when used with autochthonous plants, but these microorganisms rarely have been tested with allochthonous plants of agronomic interest. this study investigates the effectiveness of drought-adapted autochthonous microorganisms [bacillus thuringiensis (bt) and a consortium of arbuscular mycorrhizal (am) fungi] from a degraded mediterranean area to improve plant growth and physiology in zea mays unde ...201525813343
[expression of cry1ac gene directed by pexsypromoter of the exsy gene encoding component protein of exosporium basal layer in bacillus thuringiensis].to discover new elements for cry gene expression, pexsy, which is the promoter of the exosporium basal layer structural gene exsy, was used to express cry1ac gene in bacillus thuringiensis.201425803890
[transcriptional regulation of bkd gene cluster in bacillus thuringiensis].in order to determine the effect of bkdr deletion on cry protein production. we analyzed the transcriptional regulation of bkd gene cluster and the phenotype of bkdr mutant.201425803889
antimicrobial resistance and plasmid profile of bacterial strains isolated from the urbanized eltsovka-1 river (russia).antimicrobial resistance and plasmid profile of gram-positive and gram-negative bacterial strains isolated from the urbanized eltsovka-1 river (russia) were investigated. sequencing of the 16s rrna of of g+ strains showed 99-100% identity to that of bacillus aerophilus, bacillus altitudinis, bacillus amyloliquefaciens, bacillus anthrancis, bacillus barbaricus, bacillus cereus, bacillus flexus, bacillus indriensis, bacillus stratosphericus, bacillus subtilis subsp. subtilis, bacillus thuringiensi ...201525803299
understanding the long-lasting attraction of malaria mosquitoes to odor baits.the use of odor baits for surveillance and control of malaria mosquitoes requires robust dispensing tools. in this study, the residual activity of a synthetic mosquito attractant blend dispensed from nylon or low density polyethylene (ldpe) sachets was evaluated at weekly intervals for one year without re-impregnation. the potential role of bacteria in modulating the attraction of mosquitoes to odor-treated nylon that had been used repeatedly over the one year study period, without re-impregnati ...201525798818
identification of a new cry1i-type gene as a candidate for gene pyramiding in corn to control ostrinia species larvae.pyramiding of diverse cry toxin genes from bacillus thuringiensis with different modes of action is a desirable strategy to delay the evolution of resistance in the european corn borer (ostrinia nubilalis). considering the dependency of susceptibility to cry toxins on toxin binding to receptors in the midgut of target pests, a diverse mode of action is commonly defined as recognition of unique binding sites in the target insect. in this study, we present a novel cry1ie toxin gene (cry1ie2) as a ...201525795679
various enterotoxin and other virulence factor genes widespread among bacillus cereus and bacillus thuringiensis strains.many strains of bacillus cereus cause gastrointestinal diseases, and the closely related insect pathogen bacillus thuringiensis has also been involved in outbreaks of diarrhea. the diarrheal diseases are attributed to enterotoxins. sixteen reference strains of b. cereus and nine commercial and 12 reference strains of b. thuringiensis were screened by pcr for the presence of 10 enterotoxigenic genes (hbla, hblc, hbld, nhea, nheb, nhec, cytk, bcet, entfm, and ents), one emetogenic gene (ces), seve ...201525791850
fitness costs of cry1f resistance in two populations of fall armyworm, spodoptera frugiperda (j.e. smith), collected from puerto rico and florida.the development of resistance in target pest populations is a threat to the sustainability of transgenic crops expressing bacillus thuringiensis (bt) proteins. fall armyworm, spodoptera frugiperda (j.e. smith), is a major target pest of bt maize in north and south america. this insect is the first target pest that has developed field resistance to bt maize at multiple locations in these regions. the objective of this study was to assess the fitness costs associated with the cry1f resistance in t ...201525791021
bacterial melanin promotes recovery after sciatic nerve injury in rats.bacterial melanin, obtained from the mutant strain of bacillus thuringiensis, has been shown to promote recovery after central nervous system injury. it is hypothesized, in this study, that bacterial melanin can promote structural and functional recovery after peripheral nerve injury. rats subjected to sciatic nerve transection were intramuscularly administered bacterial melanin. the sciatic nerve transected rats that did not receive intramuscular administration of bacterial melanin served as co ...201525788932
potential of plant growth promoting traits by bacteria isolated from heavy metal contaminated soils.rhizobacteria can enhance biomass production and heavy metal tolerance of plants under the stress environment. the aim of this study was to collect soil samples from different industrial sites followed by their heavy metal analysis. after performing the icp-aes analysis of soil samples from seven different sites, bacterial strains were isolated from the soil samples of most polluted (heavy metal) site. phylogenetic analysis of isolates based on 16s rdna sequences showed that the isolates belonge ...201525782590
comparative analysis of genomics and proteomics in bacillus thuringiensis 4.0718.bacillus thuringiensis is a widely used biopesticide that produced various insecticidal active substances during its life cycle. separation and purification of numerous insecticide active substances have been difficult because of the relatively short half-life of such substances. on the other hand, substances can be synthetized at different times during development, so samples at different stages have to be studied, further complicating the analysis. a dual genomic and proteomic approach would e ...201525781161
isolation and distribution of mosquito-larvicidal cry genes in bacillus thuringiensis strains native to saudi arabia.a total of 157 environmental samples were collected from 11 ecological regions across saudi arabia to isolate native bacillus thuringiensis (bt) strains. bt isolates (n=103) were recovered by the 50% (v/v) ethanol treatment method with bt index range of 0.01 to 0.4. most of bt isolates showed spherical crystals (54%), while, irregular, bi-pyramidal, and spore-attached crystal constituted 27, 16 and 3% respectively. pcr analysis with eight general and specific dipteran primers of cry and cyt gene ...201425776587
pxo16 from bacillus thuringiensis serovar israelensis: almost 350 kb of terra incognita.bacillus thuringiensis strains usually harbor large sets of plasmids, some of which carrying the entomopathogenic δ-endotoxins. b. thuringiensis serovar israelensis, active on dipteran larvae, carries the very large conjugative plasmid pxo16 (350 kb). pxo16 displays a macroscopic aggregation phenotype when liquid cultures of conjugative partners are mixed. its conjugative apparatus is able of transferring itself and other non-conjugative and non-mobilizable plasmids in a fast and very efficient ...201525770691
chitosan/dsirna nanoparticle targeting identifies agcad1 cadherin in anopheles gambiae larvae as an in vivo receptor of cry11ba toxin of bacillus thuringiensis subsp. jegathesan.the cry11ba protein of bacillus thuringiensis subsp. jegathesan crystals has uniquely high toxicity against a spectrum of mosquito species. the high potency of cry11ba against anopheles gambiae is caused by recognition of multiple midgut proteins including glycosyl phosphatidylinositol-anchored alkaline phosphatase agalp1, aminopeptidase agapn2, α-amylase agamy1 and α-glucosidase agm3 that bind cry11ba with high affinity and function as putative receptors. the cadherin agcad2 in an. gambiae larv ...201525758367
cadherin is involved in the action of bacillus thuringiensis toxins cry1ac and cry2aa in the beet armyworm, spodoptera exigua.bacillus thuringiensis (bt) insecticidal crystal (cry) proteins are effective against some insect pests in sprays and transgenic crops, although the evolution of resistance could threaten the long-term efficacy of such bt use. one strategy to delay resistance to bt crops is to "pyramid" two or more bt proteins that bind to distinct receptor proteins within the insect midgut. the most common bt pyramid in cotton (gossypium hirsutum l.) employs cry1ac with cry2ab to target several key lepidopteran ...201525754522
bacillus halodurans strain c125 encodes and synthesizes enzymes from both known pathways to form dump directly from cytosine deoxyribonucleotides.analysis of the genome of bacillus halodurans strain c125 indicated that two pathways leading from a cytosine deoxyribonucleotide to dump, used for dtmp synthesis, were encoded by the genome of the bacterium. the genes that were responsible, the comeb gene and the dcdb gene, encoding dcmp deaminase and the bifunctional dctp deaminase:dutpase (dcd:dut), respectively, were both shown to be expressed in b. halodurans, and both genes were subject to repression by the nucleosides thymidine and deoxyc ...201525746996
pathway and kinetics of cyhalothrin biodegradation by bacillus thuringiensis strain zs-19.cyhalothrin is a common environmental pollutant which poses increased risks to non-target organisms including human beings. this study reported for the first time a newly isolated strain, bacillus thuringiensis zs-19 completely degraded cyhalothrin in minimal medium within 72 h. the bacterium transformed cyhalothrin by cleavage of both the ester linkage and diaryl bond to yield six intermediate products. moreover, a novel degradation pathway of cyhalothrin in strain zs-19 was proposed on the bas ...201525740758
new cyt-like δ-endotoxins from dickeya dadantii: structure and aphicidal activity.in the track of new biopesticides, four genes namely cyta, cytb, cytc and cytd encoding proteins homologous to bacillus thuringiensis (bt) cyt toxins have been identified in the plant pathogenic bacteria dickeya dadantii genome. here we show that three cyt-like δ-endotoxins from d. dadantii (cyta, cytb and cytc) are toxic to the pathogen of the pea aphid acyrthosiphon pisum in terms of both mortality and growth rate. the phylogenetic analysis of the comprehensive set of cyt toxins available in g ...201525740111
binding analysis of bacillus thuringiensis cry1 proteins in the sugarcane borer, diatraea saccharalis (lepidoptera: crambidae).sugarcane borer (diatraea saccharalis, f.) is an important corn pest in south america and united states. the aim of the present study was to analyze the susceptibility and binding interactions of three cry1a proteins and cry1fa in a brazilian d. saccharalis population. the results showed that cry1ab was the most active, followed by cry1ac, cry1fa and cry1aa. all cry1-biotinylated proteins tested bound specifically to the d. saccharalis brush border membrane vesicles (bbmv). heterologous competit ...201525736726
effects of bacillus thuringiensis israelensis and spinosad on adult emergence of the non-biting midges polypedilum nubifer (skuse) and tanytarsus curticornis kieffer (diptera: chironomidae) in coastal wetlands.to optimize their efficacy, some insecticides used for mosquito control are introduced into aquatic ecosystems where mosquito larvae develop (marshes, ponds, sanitation devices) and cannot escape from the treated water. however, this raises the question of possible effects of mosquito larvicides on non-target aquatic species. bacillus thuringiensis var. israelensis (bti), which is well-known for its selectivity for nematocera dipterans, is widely used for mosquito control all over the world. spi ...201525728359
4-hydroxyisoleucine production of recombinant corynebacterium glutamicum ssp. lactofermentum under optimal corn steep liquor limitation.4-hydroxyisoleucine (4-hil) is a nonproteinogenic amino acid that exhibits insulinotropic biological activity. here, l-isoleucine dioxygenase gene (ido) derived from bacillus thuringiensis ybt-1520 was cloned and expressed in an l-isoleucine-producing strain, corynebacterium glutamicum ssp. lactofermentum sn01, in order to directly convert its endogenous l-isoleucine (ile) into 4-hil through single-step fermentation. the effects of corn steep liquor limitation as well as ido and truncated idoδ6 ...201525725632
distinguishing the dominant species of pathogen in maxillary sinusitis by sequencing dna dataset analysis.this study determined the microbial composition in maxillary sinusitis and determined the predominant fungal and bacterial species. samples were obtained from 11 patients with fungal sinusitis and 2 healthy patients. the 13 samples were sequenced using an illumina hi-seq 2000, and mapping to the human, bacterial, and the fungal genomes were based on several steps. bioinformatics and statistical analyses were then performed for bacterial and fungal expressions in the samples. all samples were cul ...201525724392
high resistance of transgenic cabbage plants with a synthetic cry1ia8 gene from bacillus thuringiensis against two lepidopteran species under field conditions.plutella xylostella (linnaeus) has become the most destructive pest in cabbage throughout the world. cry1ia8 cabbage has been developed to reduce pest attacks. to gain a better understanding of the efficacy of cry1ia8 cabbage, a homozygous cry1ia8 cabbage line a14-5 was produced, and its resistance to p. xylostella, pieris rapae (linnaeus) and other lepidopteran pests was evaluated in the field in 2011, 2012 and 2013.201625721816
enhancement of bacillus thuringiensis insecticidal activity by combining cry1ac and bi-functional toxin hwtx-xi from spider.in order to assess the potency of bi-functional hwtx-xi toxin from spider ornithoctonus huwena in improving the insecticidal activity of bacillus thuringiensis, a fusion gene of cry1ac and hwtx-xi was constructed and expressed in an acrystalliferous b. thuringiensis strain cry(-)b. western blot analysis and microscopic observation revealed that the recombinant strain could express 140-kda cry1ac-hwtx-xi fusion protein and produce parasporal inclusions during sporulation. bioassay using the larva ...201625721170
overlapping and unique signatures in the proteomic and transcriptomic responses of the nematode caenorhabditis elegans toward pathogenic bacillus thuringiensis.pathogen infection can activate multiple signaling cascades that ultimately alter the abundance of molecules in cells. this change can be measured both at the transcript and protein level. studies analyzing the immune response at both levels are, however, rare. here, we compare transcriptome and proteome data generated after infection of the nematode and model organism caenorhabditis elegans with the gram-positive pathogen bacillus thuringiensis. our analysis revealed a high overlap between abun ...201525720978
spore prevalence and toxigenicity of bacillus cereus and bacillus thuringiensis isolates from u.s. retail spices.recent incidents of foodborne illness associated with spices as the vehicle of transmission prompted this examination of u.s. retail spices with regard to bacillus cereus. this study focused on the levels of aerobic-mesophilic spore-forming bacteria and b cereus spores associated with 247 retail spices purchased from five states in the united states. samples contained a wide range of aerobic-mesophilic bacterial spore counts (< 200 to 8.3 × 10(7) cfu/g), with 19.1% of samples at levels above 10( ...201525719886
the distribution pattern of dna and protoxin in bacillus thuringiensis as revealed by laser confocal microscopy analysis.it was reported that the parasporal crystal from bacillus thuringiensis contained dna fragments. to investigate the distribution of protoxin and dna in b. thuringiensis cells at different growth stages, a cry1ac-gfp fusion gene was constructed and expressed in an acrystalliferous b. thuringiensis strain, in which the localization of dna and protoxin were indicated by dna-specific dye and green fluorescent protein, respectively. when the recombinant cells were at the vegetative growth stage, the ...201525715783
maintenance of residual activity of bt toxin by using natural and synthetic dyes: a novel approach for sustainable mosquito vector control.mosquito control protein from bacillus thuringiensis gets inactivated with exposure to sunlight. to address this issue, the potential of synthetic and natural dye was investigated as sunlight protectants. bt sv2 in absence of dyes when exposed to sunlight showed reduced effectiveness against the fourth instars of mosquito larvae. whereas acriflavin, congo red and violacein were able to maintain 86.4%, 91.6% and 82.2% mosquito larvicidal efficacy of bt sv2 against ivth instars larvae of anopheles ...201525699646
identification of bacillus thuringiensis cry3aa toxin domain ii loop 1 as the binding site of tenebrio molitor cadherin repeat cr12.bacillus thuringiensis cry toxins exert their toxic effect by specific recognition of larval midgut proteins leading to oligomerization of the toxin, membrane insertion and pore formation. the exposed domain ii loop regions of cry toxins have been shown to be involved in receptor binding. insect cadherins have shown to be functionally involved in toxin binding facilitating toxin oligomerization. here, we isolated a vhh (vhha5) antibody by phage display that binds cry3aa loop 1 and competed with ...201525698611
functional assembly of 260-kda oligomers required for mosquito-larvicidal activity of the bacillus thuringiensis cry4ba toxin.oligomerization has been shown to contribute to the toxicity of bacillus thuringiensis cry toxins. mutations have been made in the cry4ba toxin and resulted in toxic to non-toxic mutants toward aedes aegypti larvae. in this study, cry4ba wild type and mutants were analyzed for oligomer formation in vitro, biochemical properties and their relationships with larvicidal activity. in vitro, the cry4ba forms two-main types of the oligomers including (1) the 260-kda and larger oligomers, which assembl ...201525687547
dark fermentative bioconversion of glycerol to hydrogen by bacillus thuringiensis.biodiesel manufacturing units discharge effluents rich in glycerol. the need is to convert crude glycerol (cg) into useful products such as hydrogen (h2). under batch culture, bacillusthuringiensis egu45 adapted on pure glycerol (pg, 2% v/v) resulted in an h2 yield of 0.646 mol/mol glycerol consumed on minimal media (250 ml) supplemented with 1% ammonium nitrate at 37°c over 4 days. here, h2 constituted 67% of the total biogas. under continuous culture, at 2 days of hydraulic retention time, b. ...201525686722
tribolium castaneum immune defense genes are differentially expressed in response to bacillus thuringiensis toxins sharing common receptor molecules and exhibiting disparate toxicity.in tribolium castaneum larvae we have demonstrated by rna interference knockdown that the bacillus thuringiensis cry3ba toxin receptors cadherin-like and sodium solute symporter proteins are also functional receptors of the less active cry3aa toxin. differences in susceptibility to b. thuringiensis infection might not only rely on toxin-receptor interaction but also on host defense mechanisms. we compared the expression of the immune related genes encoding apolipophorin-iii and two antimicrobial ...201525684675
lack of fitness costs and inheritance of resistance to bacillus thuringiensis cry1ac toxin in a near-isogenic strain of plutella xylostella (lepidoptera: plutellidae).resistance to bacillus thuringiensis (bt) formulations in insects may be associated with fitness costs. a lack of costs enables resistance alleles to persist, which may contribute to the rapid development and spread of resistance in populations.201625684167
molecular docking and site-directed mutagenesis of a bacillus thuringiensis chitinase to improve chitinolytic, synergistic lepidopteran-larvicidal and nematicidal activities.bacterial chitinases are useful in the biocontrol of agriculturally important pests and fungal pathogens. however, the utility of naturally occurring bacterial chitinases is often limited by their low enzyme activity. in this study, we constructed mutants of a bacillus thuringiensis chitinase with enhanced activity based on homology modeling, molecular docking, and the site-directed mutagenesis of target residues to modify spatial positions, steric hindrances, or hydrophilicity/hydrophobicity. w ...201525678849
establishment and characterization of a novel cell line from midgut tissue of helicoverpa armigera (lepidoptera: noctuidae).the midgut of lepidopteran larvae serves as a target for many pathogens such as bacillus thuringiensis (bt). cell lines originating from midgut tissues will be very helpful tools in many research fields. however, to date, no bt-susceptible midgut-derived cell lines are available. here, we reported that a novel cell line, designated as hnu-ha-mg1, was established from midgut tissue of the fourth instar larvae of helicoverpa armigera. this cell line grew well in grace's insect cell culture medium ...201525678461
evaluation of biostimulation and tween 80 addition for the bioremediation of long-term ddt-contaminated soil.the bioremediation of a long-term contaminated soil through biostimulation and surfactant addition was evaluated. the concentrations of 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (ddt) and its metabolites 1,1-dichloro-2,2-bis(4-chlorophenyl) ethane (ddd) and 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (dde) were monitored during an 8-week remediation process. physicochemical characterization of the treated soil was performed before and after the bioremediation process. the isolation and id ...201525662244
endogenous expression of a bt toxin receptor in the cry1ac-susceptible insect cell line and its synergistic effect with cadherin on cytotoxicity of activated cry1ac.although many insect cell lines derived from various tissues are available, it is unclear whether endogenous receptors of bacillus thuringiensis (bt) crystal toxins are expressed in these cell lines. in the present study, we demonstrated that the ovaries-derived spodoptera litura sl-hp cell line was susceptible to activated cry1ac although larvae of s. litura are not susceptible to the toxin. assays of the transcriptome revealed that thirteen atp-binding cassette transporter genes (abc) were exp ...201525662100
pathogenicity and characterization of a novel bacillus cereus sensu lato isolate toxic to the mediterranean fruit fly ceratitis capitata wied.the lethal and sub-lethal effects of sporulated cultures of a novel bacillus cereus sensu lato strain lacking detectable cry genes and identified through morphological and genetic analyses, have been studied on the mediterranean fruit fly ceratitis capitata. the lethal effects on young larvae were concentration dependent, with a median lethal concentration (lc50) of 4.48 × 10(8)spores/g of diet. sporulated cultures of this strain significantly extended development time and reduced immature survi ...201525659732
the expression and crystallization of cry65aa require two c-termini, revealing a novel evolutionary strategy of bacillus thuringiensis cry proteins.the insecticidal crystal protein (cry) genes of bacillus thuringiensis are a key gene resource for generating transgenic crops with pest resistance. however, many cry genes cannot be expressed or form crystals in mother cells. here, we report a novel cry protein gene, cry65aa1, which exists in an operon that contains a downstream gene encoding a hypothetical protein orf2. we demonstrated that orf2 is required for cry65aa1 expression and crystallization by function as a c-terminal crystallization ...201525656389
rotary-based platform with disposable fluidic modules for automated isolation of nucleic acids.we describe the development and evaluation of a rotary-based platform with multiple disposable fluidic modules for simultaneous automatic nucleic acid (na) isolation from up to 24 biological samples. the procedure is performed inside insulated individual disposable modules, which minimizes both the risk of infection of personnel and laboratory cross-contamination. each module is a segment of a circular cylinder containing a leak-proof inlet port for sample input, reservoirs with lyophilized chem ...201525653066
effects of refuges on the evolution of resistance to transgenic corn by the western corn rootworm, diabrotica virgifera virgifera leconte.diabrotica virgifera virgifera leconte is a major pest of corn and causes over a billion dollars of economic loss annually through yield reductions and management costs. corn producing toxins derived from bacillus thuringiensis (bt) has been developed to help manage d. v. virgifera. however, previous studies have demonstrated the ability of this species to evolve resistance to bt toxins in both laboratory and field settings.201625652190
evaluation of alternative plutella xylostella control by two isaria fumosorosea conidial formulations - oil-based formulation and wettable powder - combined with bacillus thuringiensis.entomopathogenic fungi are potential candidates for controlling the diamondback moth plutella xylostella (l.) (lepidoptera: plutellidae). the control efficacy of two isaria fumosorosea conidial formulations - wettable powder and oil-based formulation - combined with bacillus thuringiensis against p. xylostella was tested.201525641869
[influence of coordination compounds of germanium (iv) and stannum (iv) on activity of some microbial enzymes with glycolytic and proteolytic action].influence of coordinative compounds of germanium (iv) and stanum (iv) (complexes of germanium (iv) with nicotinamide (nad) [gecl2(nad)4]cl2 (1) and complexes of stanum (iv) with 2-hydroxybenzoilhydrazone 4-dimetylaminobenzaldehide (2-oh-hbdb) [sncl4(2-oh-bdb-h)] (2), 3-hydroxy-2-naphtoilhydrazone 2-hydroxynaphtaldehide (3-oh-h2lnf) [sncl3(3-oh-hlnf)] (3) and izonicotinoilhydrazone 2-hydroxyibenzaldehide [sncl3 (is·h)] (4) on activity of peptidases 1 and 2 bacillus thuringiensis, α-l-rhamnosidase ...201525639038
down-regulation of a novel abc transporter gene (pxwhite) is associated with cry1ac resistance in the diamondback moth, plutella xylostella (l.).biopesticides or transgenic crops based on cry toxins from the soil bacterium bacillus thuringiensis (bt) effectively control agricultural insect pests. the sustainable use of bt biopesticides and bt crops is threatened, however, by the development of cry resistance in the target pests. the diamondback moth, plutella xylostella (l.), is the first pest that developed resistance to a bt biopesticide in the field, and a recent study has shown that the resistance of p. xylostella to cry1ac is caused ...201525636859
optimizing pyramided transgenic bt crops for sustainable pest management.transgenic crop pyramids producing two or more bacillus thuringiensis (bt) toxins that kill the same insect pest have been widely used to delay evolution of pest resistance. to assess the potential of pyramids to achieve this goal, we analyze data from 38 studies that report effects of ten bt toxins used in transgenic crops against 15 insect pests. we find that compared with optimal low levels of insect survival, survival on currently used pyramids is often higher for both susceptible insects an ...201525599179
the midgut cadherin-like gene is not associated with resistance to bacillus thuringiensis toxin cry1ac in plutella xylostella (l.).the gram-positive bacterium bacillus thuringiensis (bt) produces cry toxins that have been used to control important agricultural pests. evolution of resistance in target pests threatens the effectiveness of these toxins when used either in sprayed biopesticides or in bt transgenic crops. although alterations of the midgut cadherin-like receptor can lead to bt cry toxin resistance in many insects, whether the cadherin gene is involved in cry1ac resistance of plutella xylostella (l.) remains uncl ...201525595643
design, synthesis and biological evaluation of metronidazole-thiazole derivatives as antibacterial inhibitors.a series of metronidazole–thiazole derivatives has been designed, synthesized and evaluated as potential antibacterial inhibitors. all the synthesized compounds were determined by elemental analysis, (1)h nmr and ms. they were also tested for antibacterial activity against escherichia coli, bacillus thuringiensis, bacillus subtilis and pseudomonas aeruginosa as well as for the inhibition to fabh. the results showed that compound 5 e exhibited the most potent inhibitory activity against e. coli f ...201425587588
cross-resistance and interactions between bt toxins cry1ac and cry2ab against the cotton bollworm.to delay evolution of pest resistance to transgenic crops producing insecticidal proteins from bacillus thuringiensis (bt), the "pyramid" strategy uses plants that produce two or more toxins that kill the same pest. we conducted laboratory diet experiments with the cotton bollworm, helicoverpa armigera, to evaluate cross-resistance and interactions between two toxins in pyramided bt cotton (cry1ac and cry2ab). selection with cry1ac for 125 generations produced 1000-fold resistance to cry1ac and ...201525586723
assessing the role of non-cotton refuges in delaying helicoverpa armigera resistance to bt cotton in west africa.non-cotton host plants without bacillus thuringiensis (bt) toxins can provide refuges that delay resistance to bt cotton in polyphagous insect pests. it has proven difficult, however, to determine the effective contribution of such refuges and their role in delaying resistance evolution. here, we used biogeochemical markers to quantify movement of helicoverpa armigera moths from non-cotton hosts to cotton fields in three agricultural landscapes of the west african cotton belt (cameroon) where bt ...201225568029
adaptive management of pest resistance by helicoverpa species (noctuidae) in australia to the cry2ab bt toxin in bollgard ii® cotton.in australia, monitoring helicoverpa species for resistance to the cry2ab toxin in second generation bacillus thuringiensis (bt) cotton has precisely fulfilled its intended function: to warn of increases in resistance frequencies that may lead to field failures of the technology. prior to the widespread adoption of two-gene bt cotton, the frequency of cry2ab resistance alleles was at least 0.001 in h. armigera and h. punctigera. in the 5 years hence, there has been a significant and apparently e ...201025567948
evolutionary ecology of insect adaptation to bt crops.transgenic crops producing bacillus thuringiensis (bt) toxins are used worldwide to control major pests of corn and cotton. development of strategies to delay the evolution of pest resistance to bt crops requires an understanding of factors affecting responses to natural selection, which include variation in survival on bt crops, heritability of resistance, and fitness advantages associated with resistance mutations. the two main strategies adopted for delaying resistance are the refuge and pyra ...201025567947
consumption of bt rice pollen containing cry1c or cry2a does not pose a risk to propylea japonica (thunberg) (coleoptera: coccinellidae).as a pollen feeder, propylea japonica would be directly exposed to cry proteins in bacillus thuringiensis (bt)-transgenic rice fields. the effect of cry1c- or cry2a-containing transgenic rice pollen on the fitness of p. japonica was assessed using two dietary-exposure experiments in the laboratory. in the first experiment, larval developmental time of p. japonica was significantly longer when fed pollen from bt rice lines rather than control pollen but other life table parameters were not signif ...201525567127
genetic markers for western corn rootworm resistance to bt toxin.western corn rootworm (wcr) is a major maize (zea mays l.) pest leading to annual economic losses of more than 1 billion dollars in the united states. transgenic maize expressing insecticidal toxins derived from the bacterium bacillus thuringiensis (bt) are widely used for the management of wcr. however, cultivation of bt-expressing maize places intense selection pressure on pest populations to evolve resistance. instances of resistance to bt toxins have been reported in wcr. developing genetic ...201525566794
inheritance, fitness costs, incomplete resistance and feeding preferences in a laboratory-selected mon810-resistant strain of the true armyworm mythimna unipuncta.the low efficacy of mon810 maize against mythimna unipuncta represents a scenario of non-compliance with the 'high-dose' strategy, raising concerns about potential resistance development and outbreaks of this secondary pest. the present study offers insight into the different components related to resistance in a laboratory-selected mon810-resistant (mr) strain of m. unipuncta.201525565147
cry1ab protein from bacillus thuringiensis and mon810 cry1ab-transgenic maize exerts no adjuvant effect after airway exposure.the genetically modified (gm) maize event mon810 has been inserted with a processed version of the transgene, cry1ab, derived from the soil bacterium bacillus thuringiensis (bt) to express proteins with insecticidal properties. such proteins may introduce new allergens and also act as adjuvants that promote allergic responses. while focus has been on safe consumption and hence the oral exposure to gm food and feed, little is known regarding inhalation of pollen and desiccated airborne plant mate ...201525564738
the diverse nematicidal properties and biocontrol efficacy of bacillus thuringiensis cry6a against the root-knot nematode meloidogyne hapla.cry6a toxin from bacillus thuringiensis is a representative nematicidal crystal protein with a variety of nematicidal properties to free-living nematode caenorhabditis elegans. cry6a shares very low homology and different structure with cry5b, another representative nematicidal crystal protein, and probably acts in a distinct pathway. all these strongly indicate that cry6a toxin is likely a potent candidate for nematicide. the present study dealt with global investigation to determine the detrim ...201525556591
complete genome sequence of bacillus thuringiensis serovar galleriae strain hd-29, a typical strain of commercial biopesticide.bacillus thuringiensis serovar galleriae is highly toxic to lepidoptera insect pests, and has been widely used as bt biopesticide in many countries. here we reported the complete genome of strain hd-29, a standard serotype strain in galleriae serovariety. more than previous work reported, it harbors ten plasmids, and three large ones carry eight insecticidal protein genes (cry1aa, cry1ac, cry1ca, cry1da, cry1ia, cry2ab, cry9ea and vip3aa) and an intact zwittermicin a biosynthetic gene cluster.201525556027
aquatic degradation of cry1ab protein and decomposition dynamics of transgenic corn leaves under controlled conditions.the increasing cultivation of genetically modified corn plants (zea mays) during the last decades is suggested as a potential risk to the environment. one of these genetically modified variety expressed the insecticidal cry1ab protein originating from bacillus thuringiensis (bt), resulting in resistance against ostrinia nubilalis, the european corn borer. transgenic litter material is extensively studied regarding the decomposition in soils. however, only a few field studies analyzed the fate of ...201525553417
chemical and biological insecticides select distinct gene expression patterns in aedes aegypti mosquito.worldwide evolution of mosquito resistance to chemical insecticides represents a major challenge for public health, and the future of vector control largely relies on the development of biological insecticides that can be used in combination with chemicals (integrated management), with the expectation that populations already resistant to chemicals will not become readily resistant to biological insecticides. however, little is known about the metabolic pathways affected by selection with chemic ...025540155
efficacy of an alphabaculovirus-based biological insecticide for control of chrysodeixis chalcites (lepidoptera: noctuidae) on tomato and banana crops.chrysodeixis chalcites (esper) is a major pest of tomato in mediterranean countries and attacks banana in the canary islands (spain). the efficacy of chrysodeixis chalcites single nucleopolyhedrovirus (chchsnpv-tf1) was evaluated in plant growth chambers and greenhouse trials performed on tomato and banana plants respectively. treatments were applied using a compressed air sprayer.201525534715
identification of micrornas by small rna deep sequencing for synthetic microrna mimics to control spodoptera exigua.beet armyworm, spodoptera exigua, is a major pest of cotton around the world. with the increase of resistance to bacillus thuringiensis (bt) toxin in transgenic cotton plants, there is a need to develop an alternative control approach that can be used in combination with bt transgenic crops as part of resistance management strategies. micrornas (mirnas), a non-coding small rna family (18-25 nt), play crucial roles in various biological processes and over-expression of mirnas has been shown to in ...201525528266
activation of gab cluster transcription in bacillus thuringiensis by γ-aminobutyric acid or succinic semialdehyde is mediated by the sigma 54-dependent transcriptional activator gabr.bacillus thuringiensis gabr is a sigma 54-dependent transcriptional activator containing three typical domains, an n-terminal regulatory domain per-arnt-sim (pas), a central aaa(+) (atpases associated with different cellular activities) domain and a c-terminal helix-turn-helix (hth) dna binding domain. gabr positively regulates the expression of the gabt gene of the gab gene cluster, which is responsible for the γ-aminobutyric acid (gaba) shunt.201425527261
analysis of resistance to cry1ac in field-collected pink bollworm, pectinophora gossypiella (lepidoptera:gelechiidae), populations.high survivorship of pink bollworrm, pectinophora gossypiella in bolls of bollgard® cotton hybrids and resistance to cry1ac protein, expressed in bollgard cotton were reported in field-populations collected from the state of gujarat (western india) in 2010. we have found cry1ac-resistance in pink bollworm populations sourced from bollgard and non-bt cotton fields in the adjoining states of maharashtra and madhya pradesh in central india. further, we observed reduced binding of labeled cry1ac pro ...201425523173
quantifying transient interactions between bacillus phosphatidylinositol-specific phospholipase-c and phosphatidylcholine-rich vesicles.bacillus thuringiensis secretes the virulence factor phosphatidylinositol-specific phospholipase c (btpi-plc), which specifically binds to phosphatidylcholine (pc) and cleaves gpi-anchored proteins off eukaryotic plasma membranes. to elucidate how btpi-plc searches for gpi-anchored proteins on the membrane surface, we measured residence times of single fluorescently labeled proteins on pc-rich small unilamellar vesicles (suvs). btpi-plc interactions with the suv surface are transient with a life ...201525517221
bacillus thuringiensis toxins: an overview of their biocidal activity.bacillus thuringiensis (bt) is a gram positive, spore-forming bacterium that synthesizes parasporal crystalline inclusions containing cry and cyt proteins, some of which are toxic against a wide range of insect orders, nematodes and human-cancer cells. these toxins have been successfully used as bioinsecticides against caterpillars, beetles, and flies, including mosquitoes and blackflies. bt also synthesizes insecticidal proteins during the vegetative growth phase, which are subsequently secrete ...201425514092
[influence of different sticky-gene composition on sporulation and protein synthesis by bacillus thuringiensis collection strains].the influence of different sticky-gene composition on sporulation and protein synthesis by b. thuringiensis collection strains has been investigated. it has been detemined that the most effective according this characteristics were b. thuringiensis collection strains 0293 and 98. it has been shown that the best on protein synthesis processes and sporulation by investigated b. thuringiensis strains influences adding to the culture medium sticky-gene compositions a and e in a concentration of from ...201425507811
large-scale test of the natural refuge strategy for delaying insect resistance to transgenic bt crops.the 'natural refuge strategy" for delaying insect resistance to transgenic cotton that produces insecticidal proteins from bacillus thuringiensis (bt) relies on refuges of host plants other than cotton that do not make bt toxins. we tested this widely adopted strategy by comparing predictions from modeling with data from a four-year field study of cotton bollworm (helicoverpa armigera) resistance to transgenic cotton producing bt toxin cry1ac in six provinces of northern china. bioassay data rev ...201525503384
the protoxin cry1ac of bacillus thuringiensis improves the protection conferred by intranasal immunization with brucella abortus rb51 in a mouse model.brucellosis is a zoonotic disease affecting many people and animals worldwide. preventing this infection requires improving vaccination strategies. the protoxin cry1ac of bacillus thuringiensis is an adjuvant that, in addition to increasing the immunogenicity of different antigens, has shown to be protective in different models of parasitic infections. the objective of the present study was to test whether the intranasal co-administration of pcry1ac with the rb51 vaccine strain of brucella abort ...201525497237
production of polyclonal and monoclonal antibodies against the bacillus thuringiensis vegetative insecticidal protein vip3aa16.the aim of this study is to establish a quantitative determination of the vegetative insecticidal protein vip3a from the culture supernatant of bacillus thuringiensis either by elisa or by the conventional quantification method of the western blot band. the vip3a protein was produced by fermentation of the b. thuringiensis reference strain bupm95 in 3 l. by western blot, the vip3aa16 toxin was detected in the culture supernatant during the exponential growth phase of b. thuringiensis bupm95. how ...201525492687
highly toxic and broad-spectrum insecticidal local bacillus strains engineered using protoplast fusion.protoplast fusion was performed between a local bacillus thuringiensis uv-resistant mutant 66/1a (bt) and bacillus sphaericus ghai (bs) to produce new bacillus strains with a wider spectrum of action against different insects. bt is characterized as sensitive to polymyxin and streptomycin and resistant to rifampicin and has shown 87% mortality against spodoptera littoralis larvae at concentration of 1.5 × 10(7) cells/ml after 7 days of feeding; bs is characterized as resistant to polymyxin and s ...201525485592
apolipophorin iii from honeybees (apis cerana) exhibits antibacterial activity.apolipophorin iii (apolp-iii) is involved in lipid transport and innate immunity in insects. in this study, an apolp-iii protein that exhibits antibacterial activity was identified in honeybees (apis cerana). a. cerana apolp-iii cdna encodes a 193 amino acid sequence that shares high identity with other members of the hymenopteran insect apolp-iii family. a. cerana apolp-iii is expressed constitutively in the fat body, epidermis, and venom gland and is detected as a 23-kda protein. a. cerana apo ...201525483322
resistance of trichoplusia ni populations selected by bacillus thuringiensis sprays to cotton plants expressing pyramided bacillus thuringiensis toxins cry1ac and cry2ab.two populations of trichoplusia ni that had developed resistance to bacillus thuringiensis sprays (bt sprays) in commercial greenhouse vegetable production were tested for resistance to bt cotton (bollgard ii) plants expressing pyramided cry1ac and cry2ab. the t. ni colonies resistant to bacillus thuringiensis serovar kurstaki formulations were not only resistant to the bt toxin cry1ac, as previously reported, but also had a high frequency of cry2ab-resistant alleles, exhibiting ca. 20% survival ...201525480752
heterologous expression, purification and biochemical characterization of endochitinase chia74 from bacillus thuringiensis.chia74 is a secreted endochitinase produced by bacillus thuringiensis. previously we have partially characterized the physical parameters that affect enzymatic activity of chia74 in crude preparations of bacterial secretomes. in the present study, we cloned the chia74 open reading frame (orf) lacking the 5' sequence coding for its secretion signal peptide (chia74δsp) into a cold shock expression vector (pcoldi) for production of the enzyme in escherichia coli bl21-rosetta 2. as a result, the n-t ...201525478931
detection of toxin proteins from bacillus thuringiensis strain 4.0718 by strategy of 2d-lc-ms/ms.bacillus thuringiensis is a kind of insecticidal microorganism which can produce a variety of toxin proteins, it is particularly important to find an effective strategy to identify novel toxin proteins rapidly and comprehensively with the discovery of the wild-type strains. multi-dimensional high-performance liquid chromatography combined with mass spectrometry has become one of the main methods to detect and identify toxin proteins and proteome of b. thuringiensis. in this study, protein sample ...201525477065
identification of single nucleotide polymorphisms (snps) in the 16s rrna gene of foodborne bacillus spp.the main goal of this work was the identification of single nucleotide polymorphisms (snps) in the 16s rrna gene of foodborne bacillus spp. that may be useful for typing purposes. these species include, among others, bacillus cereus, an important pathogenic species involved in food poisoning, and bacillus licheniformis, bacillus subtilis and bacillus pumilus, which are causative agents of food spoilage described as responsible for foodborne disease outbreaks. with this purpose in mind, 52 bacill ...201525475292
uniform orientation of biotinylated nanobody as an affinity binder for detection of bacillus thuringiensis (bt) cry1ac toxin.nanobodies are the smallest natural fragments with useful properties such as high affinity, distinct paratope and high stability, which make them an ideal tool for detecting target antigens. in this study, we generated and characterized nanobodies against the cry1ac toxin and applied them in a biotin-streptavidin based double antibodies (nanobodies) sandwich-elisa (das-elisa) assay. after immunizing a camel with soluble cry1ac toxin, a phage displayed library was constructed to generate nbs agai ...201425474492
chelation, spectroscopic characterization, biological activity and crystal structure of 2,3-butanedione isonicotinylhydrazone: determination of zr(4+) after flotation separation.new metal complexes of co(ii), ni(ii) cu(ii), zn(ii), cd(ii), pd(ii) and hg(ii) with 2,3-butanedione isonicotinylhydrazone [binh] have been prepared and investigated. single crystal for binh is grown and solved as orthorhombic with p 21 21 2 space group. the formula of the ligand was assigned based on the elemental analysis, mass spectra and conductivity measurements. the complexes assigned the formulae [m(binh-h)cl]⋅nh2o (mco(ii), ni(ii), cu(ii), zn(ii); n=0 or 1); [hg(binh-h)(h2o)2cl]; [cd(bin ...201525467677
contribution of arbuscular mycorrhizal fungi and/or bacteria to enhancing plant drought tolerance under natural soil conditions: effectiveness of autochthonous or allochthonous strains.autochthonous microorganisms [a consortium of arbuscular-mycorrhizal (am) fungi and bacillus thuringiensis (bt)] were assayed and compared to rhizophagus intraradices (ri), bacillus megaterium (bm) or pseudomonas putida (psp) and non-inoculation on trifolium repens in a natural arid soil under drought conditions. the autochthonous bacteria bt and the allochthonous bacteria psp increased nutrients and the relative water content and decreased stomatal conductance, electrolyte leakage, proline and ...201525462971
toxicity of bacillus thuringiensis var. israelensis in aqueous suspension on the south american common frog leptodactylus latrans (anura: leptodactylidae) tadpoles.the effects of commercial formulations of bacillus thuringiensisvar.israelensis (bti) on non-target organisms are still a matter of debate; in amphibians, the risks of bti are little known. to evaluate the toxicity of a commercial liquid (aqueous suspension, as) formulation of bti (introban(®)) on leptodactylus latrans tadpoles, including median lethal concentration (lc50) and no-and lowest-observed-effect concentrations (noec and loec, respectively), as well as the possible effects of bti on ox ...201525460638
lipopeptide biosurfactant from bacillus thuringiensis pak2310: a potential antagonist against fusarium oxysporum.the aims of the study were to evaluate the effects of a biosurfactant obtained from a novel bacillus thuringiensis on fusarium oxysporum to determine the morphological changes in the structure of the fungi and its biofilm in the presence of the biosurfactant and to evaluate the toxicity of the biosurfactant on hep-2 human epithelial cell lines.201525456418
quantitative proteome analysis of caenorhabditis elegans upon exposure to nematicidal bacillus thuringiensis.caenorhabditis elegans can be infected by a plethora of pathogens, most of them are also pathogenic for humans. consequently, the nematode has emerged as a powerful surrogate host to model microbial human infectious diseases in a non-vertebrate, for the study of innate immunity and host-pathogen interactions. signaling cascades are well investigated that face bacterial or fungal pathogens. we analyzed the downstream processes of these cascades, i.e. the differential expression of effector and re ...201525452134
the cultivation of bt corn producing cry1ac toxins does not adversely affect non-target arthropods.transgenic corn producing cry1ac toxins from bacillus thuringiensis (bt) provides effective control of asian corn borer, ostrinia furnacalis (guenée), and thus reduces insecticide applications. however, whether bt corn exerts undesirable effects on non-target arthropods (ntas) is still controversial. we conducted a 2-yr study in shangzhuang agricultural experiment station to assess the potential impact of bt corn on field population density, biodiversity, community composition and structure of n ...201425437213
[influence of different adhesive composition on sporulation and protein synthesis by bacillus thuringiensis collection strains].the influence of different sticky-gene composition on sporulation and protein synthesis by b. thuringiensis collection strains has been investigated. it has been detemined that the most effective according this characteristics were b. thuringiensis collection strains 0293 and 98. it has been shown that the best on protein synthesis processes and sporulation by investigated b. thuringiensis strains influences adding to the culture medium sticky-gene compositions a and e in a concentration of from ...201425434213
characterisation of novel bacillus thuringiensis isolates against aedes aegypti (diptera: culicidae) and ceratitis capitata (diptera: tephridae).bacillus thuringiensis is successfully used in pest management strategies as an eco-friendly bioinsecticide. isolation and identification of new strains with a wide variety of target pests is an ever growing field. in this paper, new b. thuringiensis isolates were investigated to search for original strains active against diptera and able to produce novel toxins that could be used as an alternative for the commercial h14 strain. biochemical and molecular characterization revealed a remarkable di ...201525433312
toxicity, activation process, and histopathological effect of bacillus thuringiensis vegetative insecticidal protein vip3aa16 on tuta absoluta.tuta absoluta is a destructive moth of solanaceae plants and especially tomatoes. here, we considered the entomopathogenic activity of the bacillus thuringiensis vip3aa16 protein heterologously produced by escherichia coli against t. absoluta. purified vip3aa16 showed lower lethal concentration 50 % against third instar larvae (toxin/tomato leaf) (335 ± 17 ng/cm(2)) compared to that of b. thuringiensis kurstaki hd1 δ-endotoxins (955 ± 4 ng/cm(2)) (p < 0.05). action mode examination showed that v ...201525432339
cis-mediated down-regulation of a trypsin gene associated with bt resistance in cotton bollworm.transgenic plants producing insecticidal proteins from the bacterium bacillus thuringiensis (bt) are useful for pest control, but their efficacy is reduced when pests evolve resistance. here we examined the mechanism of resistance to bt toxin cry1ac in the laboratory-selected lf5 strain of the cotton bollworm, helicoverpa armigera. this strain had 110-fold resistance to cry1ac protoxin and 39-fold resistance to cry1ac activated toxin. evaluation of five trypsin genes revealed 99% reduced transcr ...201425427690
pen and pal are nucleotide-sugar dehydratases that convert udp-glcnac to udp-6-deoxy-d-glcnac-5,6-ene and then to udp-4-keto-6-deoxy-l-altnac for cmp-pseudaminic acid synthesis in bacillus thuringiensis.cmp-pseudaminic acid is a precursor required for the o-glycosylation of flagellin in some pathogenic gram-negative bacteria, a process known to be critical in bacterial motility and infection. however, little is known about flagellin glycosylation in gram-positive bacteria. here, we identified and functionally characterized an operon, named bti_pse, in bacillus thuringiensis israelensis atcc 35646, which encodes seven different enzymes that together convert udp-glcnac to cmp-pseudaminic acid. in ...201425414257
expression of recombinant and mosaic cry1ac receptors from helicoverpa armigera and their influences on the cytotoxicity of activated cry1ac to spodoptera litura sl-hp cells.bacillus thuringiensis (bt) toxin receptors play important roles in the killing of pests, and investigation on characterization of the receptors is essential for utilization of bt and management of insect resistance. here, recombinant and mosaic receptors of bt cry1ac toxin from helicoverpa armigera were expressed in spodoptera litura sl-hp cells and their influences on cytotoxicity of activated cry1ac toxin were investigated. when h. armigera aminopeptidase n1 (apn1), alkaline phosphatase 2 (al ...201625412589
biphasic fermentation is an efficient strategy for the overproduction of δ-endotoxin from bacillus thuringiensis.this study illustrates a biphasic solid-state fermentation (ssf) strategy for the overproduction of δ-endotoxin from bacillus thuringiensis subsp. kurstaki (btk) and also purification of δ-endotoxin from the solid-fermented medium. the fermentation strategy had two phases (biphasic); i.e., the first short phase was semisolid state (12 h), and the remaining long phase was strict ssf. to achieve the biphasic ssf, after 12 h (150 rpm, 37 °c) fermentation of the medium [luria-bertani (lb) supplement ...201525410805
a challenge for the seed mixture refuge strategy in bt maize: impact of cross-pollination on an ear-feeding pest, corn earworm.to counter the threat of insect resistance, bacillus thuringiensis (bt) maize growers in the u.s. are required to plant structured non-bt maize refuges. concerns with refuge compliance led to the introduction of seed mixtures, also called rib (refuge-in-the-bag), as an alternative approach for implementing refuge for bt maize products in the u.s. maize belt. a major concern in rib is cross-pollination of maize hybrids that can cause bt proteins to be present in refuge maize kernels and negativel ...201425409442
cry1f resistance in fall armyworm spodoptera frugiperda: single gene versus pyramided bt maize.evolution of insect resistance to transgenic crops containing bacillus thuringiensis (bt) genes is a serious threat to the sustainability of this technology. however, field resistance related to the reduced efficacy of bt maize has not been documented in any lepidopteran pest in the mainland u.s. after 18 years of intensive bt maize planting. here we report compelling evidence of field resistance in the fall armyworm, spodoptera frugiperda (j.e. smith), to cry1f maize (tc 3507) in the southeaste ...201425401494
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