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[the analysis of major metabolic pathways in bacillus thuringiensis under alkaline stress].the study aimed to determine the appropriate stage for exploring the responseof bacillus thuringiensis to the alkaline stress, to profile the metabolic pathways under this stress.201627382791
crystal structure of cry6aa: a novel nematicidal clya-type α-pore-forming toxin from bacillus thuringiensis.crystal (cry) proteins from bacillus thuringiensis (bt) are globally used in agriculture as proteinaceous insecticides. numerous crystal structures have been determined, and most exhibit conserved three-dimensional architectures. recently, we have identified a novel nematicidal mechanism by which cry6aa triggers cell death through a necrosis-signaling pathway via an interaction with the host protease asp-1. however, we found little sequence conservation of cry6aa in our functional study. here, w ...201627381865
cyclic di-gmp contributes to adaption and virulence of bacillus thuringiensis through a riboswitch-regulated collagen adhesion protein.cyclic di-gmp is a ubiquitous second messenger that regulates diverse cellular processes in bacteria by binding to various protein or riboswitch effectors. in bacillus thuringiensis bmb171, a c-di-gmp riboswitch termed bc2 rna resides in the 5'-untranslated region (5'-utr) of an mrna that encodes a collagen adhesion protein (cap). the expression of cap was strongly repressed in parent strain bmb171 because of the presence of bc2 rna but was significantly promoted in the bc2 rna markerless deleti ...201627381437
toxicity of bacillus thuringiensis crystal proteins against eri silkworm, samia cynthia ricini (lepidoptera: saturniidae).ten purified crystal proteins of bacillus thuringiensis (bt) were tested at concentrations ranging from 2.93 to 3000ng/cm(2) for their toxicity to eri silkworm through protein paint bioassays using castor leaves. based on lc50 values, cry1aa (2.6ng/cm(2)) was highly toxic followed by cry1ac (29.3ng/cm(2)) and cry1ab (68.7ng/cm(2)). the cry1ca and cry1ea proteins were moderately toxic to eri silkworm larvae and resulted in 23% and 28% mortality, respectively at the highest concentration tested (3 ...201627377590
histochemical effects of some biological agents on culex pipiens larvae.the histochemical effects of the lethal concentration that kills 50% of larvae (lc50) of three biological agents, abamectin, bacillus thuringiensis and spinosad on the carbohydrates (polysaccharides), proteins, nucleic acids and lipids content of the midgut and fat bodies of culex pipiens 2nd instar larvae were studied. the results showed that the three tested compounds reduced the carbohydrates (polysaccharides), proteins, rna synthesis and lipids content after 72 hours of treatment where abame ...201627363043
adult exposure to bt toxin cry1ac reduces life span and reproduction of resistant and susceptible pink bollworm (lepidoptera: gelechiidae).insecticidal proteins from bacillus thuringiensis (bt) are used widely in sprays and transgenic plants to control insect pests. although much research has elucidated the effects of bt toxins on larvae, relatively little is known about their effects on adults. here, we evaluated the effects of exposing adults to bt toxin cry1ac on the life span and reproduction of two strains of pink bollworm (pectinophora gossypiella (saunders)). in larval diet bioassays, the concentration of cry1ac killing 50% ...201627133579
a promising hd133-like strain of bacillus thuringiensis with dual efficiency to the two lepidopteran pests: spodoptera littoralis (noctuidae) and ephestia kuehniella (pyralidae).isolation and identification of new strains with wide variety of target pests is an ever growing field. in this paper, a screening of 260 strains from tunisian soil samples was conducted by dot-blot and pcr-sequencing analysis. the screening was done on the basis of the possession of cry1d-type genes and was followed by the evaluation of the insecticidal activity against spodoptera littoralis. blb250 strain showed an lc50 value (56.2 μg g(-1)) against s. littoralis lower than those of the two ba ...201627130040
does bt maize expressing cry1ac protein have adverse effects on the parasitoid macrocentrus cingulum (hymenoptera: braconidae)?the potential effects of insect-resistant, genetically engineered (ge) crops on non-target organisms, especially on predators and parasitoids, must be evaluated before their commercial cultivation. the effects of ge maize that produces cry1ac toxin on the parasitoid macrocentrus cingulum were assessed by direct bioassay and indirect bioassay. in the indirect bioassay, parasitism rate, cocoon weight and the number of m. cingulum progeny produced per host were significantly reduced when m. cingulu ...201627126195
field-based assessment of resistance to bt corn by western corn rootworm (coleoptera: chrysomelidae).western corn rootworm, diabrotica virgifera virgifera leconte, is a serious pest of corn and is managed with corn that produces insecticidal toxins derived from the bacterium bacillus thuringiensis (bt). beginning in 2009, resistance to cry3bb1 corn, and severe injury to cry3bb1 corn in the field, was observed in iowa. however, few data exist on how cry3bb1-resistant western corn rootworm interact with various management practices in the field. using a field experiment, we measured adult emergen ...201627122498
bt toxin cry1ie causes no negative effects on survival, pollen consumption, or olfactory learning in worker honey bees (hymenoptera: apidae).the honey bee (apis mellifera l.) is a key nontarget insect in environmental risk assessments of insect-resistant genetically modified crops. in controlled laboratory conditions, we evaluated the potential effects of cry1ie toxin on survival, pollen consumption, and olfactory learning of young adult honey bees. we exposed worker bees to syrup containing 20, 200, or 20,000 ng/ml cry1ie toxin, and also exposed some bees to 48 ng/ml imidacloprid as a positive control for exposure to a sublethal con ...201627122497
continuous evolution of bacillus thuringiensis toxins overcomes insect resistance.the bacillus thuringiensis δ-endotoxins (bt toxins) are widely used insecticidal proteins in engineered crops that provide agricultural, economic, and environmental benefits. the development of insect resistance to bt toxins endangers their long-term effectiveness. here we have developed a phage-assisted continuous evolution selection that rapidly evolves high-affinity protein-protein interactions, and applied this system to evolve variants of the bt toxin cry1ac that bind a cadherin-like recept ...201627120167
frequency of cry1f non-recessive resistance alleles in north carolina field populations of spodoptera frugiperda (lepidoptera: noctuidae).fall armyworm, spodoptera frugiperda (j.e. smith) (lepidoptera: noctuidae), is a target species of transgenic corn (zea mays l.) that expresses single and pyramided bacillus thuringiensis (bt) toxin. in 2014, s. frugiperda were collected from a light trap in north carolina, and a total of 212 f1/f2 isofemale lines of s. frugiperda were screened for resistance to bt and non-bt corn. all of the 212 isolines were susceptible to corn tissue expressing cry1a.105 + cry2ab, cry1f + cry1a.105 + cry2ab, ...201627119741
experimental evolution in silico: a custom-designed mathematical model for virulence evolution of bacillus thuringiensis.most mathematical models on the evolution of virulence are based on epidemiological models that assume parasite transmission follows the mass action principle. in experimental evolution, however, mass action is often violated due to controlled infection protocols. this "theory-experiment mismatch" raises the question whether there is a need for new mathematical models to accommodate the particular characteristics of experimental evolution. here, we explore the experimental evolution model system ...201627113405
reproductive isolation between two populations of diatraea saccharalis (f.) (lepidoptera: crambidae) from different host plant species and regions in argentina.the sugarcane borer, diatraea saccharalis (f.), has a widespread distribution throughout the western hemisphere and is a pest of many crop plants including sugarcane, corn, sorghum and rice. the use of bacillus thuringiensis (bt) corn has been the primary tool for managing this species in corn fields. sugarcane borer control has been recently threatened by observations of susceptibility and/or resistance to certain varieties of bt corn and the protein used in many newer varieties. this has led t ...201627112423
biological activity of bacillus thuringiensis in drosophila suzukii (diptera: drosophilidae).whole-culture extracts of bacillus thuringiensis berliner strains were assayed against larval and adult drosophila suzukii (matsumura), an important invasive pest of many thin-skinned soft fruit crops in north america. of the 22 serovars tested versus larval d. suzukii, strains of bacillus thuringiensis var. thuringiensis, kurstaki, thompsoni, bolivia, and pakistani caused high (75 to 100%) first-instar mortalities. pupal mortality, measured as a failure of adults to emerge, varied with serovar. ...201627106227
multiple assays indicate varying levels of cross resistance in cry3bb1-selected field populations of the western corn rootworm to mcry3a, ecry3.1ab, and cry34/35ab1.minnesota populations of diabrotica virgifera virgifera leconte, the western corn rootworm, surviving cry3bb1-expressing corn in the field and western corn rootworm populations assumed to be susceptible to all bt proteins were evaluated for susceptibility to cry3bb1, mcry3a, ecry3.1ab, and cry34/35ab1 in diet assays and three different plant-based assays. rootworm populations originating from cry3bb1 fields and that consistently experienced greater than expected damage had increased survival and ...201627106225
assessment of potential adjuvanticity of cry proteins.genetically modified (gm) crops have achieved success in the marketplace and their benefits extend beyond the overall increase in harvest yields to include lowered use of insecticides and decreased carbon dioxide emissions. the most widely grown gm crops contain gene/s for targeted insect protection, herbicide tolerance, or both. plant expression of bacillus thuringiensis (bt) crystal (cry) insecticidal proteins have been the primary way to impart insect resistance in gm crops. although deemed s ...201627105772
impact of violated high-dose refuge assumptions on evolution of bt resistance.transgenic crops expressing bacillus thuringiensis (bt) toxins have been widely and successfully deployed for the control of target pests, while allowing a substantial reduction in insecticide use. the evolution of resistance (a heritable decrease in susceptibility to bt toxins) can pose a threat to sustained control of target pests, but a high-dose refuge (hdr) management strategy has been key to delaying countervailing evolution of bt resistance. the hdr strategy relies on the mating frequency ...201627099624
application of a dense genetic map for assessment of genomic responses to selection and inbreeding in heliothis virescens.adaptation of pest species to laboratory conditions and selection for resistance to toxins in the laboratory are expected to cause inbreeding and genetic bottlenecks that reduce genetic variation. heliothis virescens, a major cotton pest, has been colonized in the laboratory many times, and a few laboratory colonies have been selected for bacillus thuringiensis (bt) resistance. we developed 350-bp double-digest restriction-site associated dna-sequencing (ddrad-seq) molecular markers to examine a ...201627097739
characterization of the resistance to vip3aa in helicoverpa armigera from australia and the role of midgut processing and receptor binding.crops expressing genes from bacillus thuringiensis (bt crops) are among the most successful technologies developed for the control of pests but the evolution of resistance to them remains a challenge. insect resistant cotton and maize expressing the bt vip3aa protein were recently commercialized, though not yet in australia. we found that, although relatively high, the frequency of alleles for resistance to vip3aa in field populations of h. armigera in australia did not increase over the past fo ...201627095284
use of redundant exclusion pcr to identify a novel bacillus thuringiensis cry8 toxin gene from pooled genomic dna.with the aim of optimizing the cloning of novel genes from a genomic pool containing many previously identified homologous genes, we designed a redundant exclusion pcr (re-pcr) technique. in re-pcr, a pair of generic amplification primers are combined with additional primers that are designed to specifically bind to redundant, unwanted genes that are a subset of those copied by the amplification primers. during re-pcr, the specific primer blocks amplification of the full-length redundant gene. u ...201627084017
contrasting invertebrate immune defense behaviors caused by a single gene, the caenorhabditis elegans neuropeptide receptor gene npr-1.the invertebrate immune system comprises physiological mechanisms, physical barriers and also behavioral responses. it is generally related to the vertebrate innate immune system and widely believed to provide nonspecific defense against pathogens, whereby the response to different pathogen types is usually mediated by distinct signalling cascades. recent work suggests that invertebrate immune defense can be more specific at least at the phenotypic level. the underlying genetic mechanisms are as ...201627066825
heritability of wing size and shape of the rice and corn strains of spodoptera frugiperda (j.e. smith) (lepidoptera: noctuidae).spodoptera frugiperda (j.e. smith) (lepidoptera: noctuidae) represents a pest of economic importance in all western hemisphere. this polyphagous species has diverged into two populations that have been mainly recognized with various mitochondrial and nuclear molecular markers and named "the rice" and "the corn" strains. in colombia, both strains have evolved prezygotic and postzygotic isolation. they differ in tolerance to bacillus thuringiensis (cry1ac and cry1ab endotoxins) and the insecticide ...201627044394
effects of illuminance and nutrients on bacterial photo-physiology of hydrocarbon degradation.bacterial photophysiology was previously limited to photoautotrophs. the discovery of bacteriophytochromes in non-photoautotrophs raised a question whether these non-photoautotrophs are affected by the presence or absence of light? in this research work for the first time, bacterial hydrocarbon degradation and biomass production was studied under the influence of nutrients, illuminance (light flux) and time. an experimental model was designed, with six isolated bacterial strains (pseudomonas poa ...201627039061
heme sensing in bacillus thuringiensis: a supplementary hssrs-regulated heme resistance system.several gram-positive pathogens scavenge host-derived heme to satisfy their nutritional iron requirement. however, heme is a toxic molecule capable of damaging the bacterial cell. gram-positive pathogens within the phylum firmicutes overcome heme toxicity by sensing heme through hssrs, a two-component system that regulates the heme detoxification transporter hrtab. here we show that heme sensing by hssrs and heme detoxification by hrtab occur in the insect pathogen bacillus thuringiensis we find ...201627030728
immuno-physiological adaptations confer wax moth galleria mellonella resistance to bacillus thuringiensis.microevolutionary mechanisms of resistance to a bacterial pathogen were explored in a population of the greater wax moth, galleria mellonella, selected for an 8.8-fold increased resistance against the entomopathogenic bacterium bacillus thuringiensis (bt) compared with a non-selected (suspectible) line. defense strategies of the resistant and susceptible insect lines were compared to uncover mechanisms underpinning resistance, and the possible cost of those survival strategies. in the uninfected ...201627029421
a role for weak electrostatic interactions in peripheral membrane protein binding.bacillus thuringiensis phosphatidylinositol-specific phospholipase c (btpi-plc) is a secreted virulence factor that binds specifically to phosphatidylcholine (pc) bilayers containing negatively charged phospholipids. btpi-plc carries a negative net charge and its interfacial binding site has no obvious cluster of basic residues. continuum electrostatic calculations show that, as expected, nonspecific electrostatic interactions between btpi-plc and membranes vary as a function of the fraction of ...201627028646
transcriptional profiling analysis of spodoptera litura larvae challenged with vip3aa toxin and possible involvement of trypsin in the toxin activation.vip proteins, a new group of insecticidal toxins produced by bacillus thuringiensis, are effective against specific pests including spodoptera litura. here, we report construction of a transcriptome database of s. litura by de novo assembly along with detection of the transcriptional response of s. litura larvae to vip3aa toxin. in total, 56,498 unigenes with an n50 value of 1,853 bp were obtained. results of transcriptome abundance showed that vip3aa toxin provoked a wide transcriptional respon ...201627025647
a mixture of bacillus thuringiensis subsp. israelensis with xenorhabdus nematophila-cultured broth enhances toxicity against mosquitoes aedes albopictus and culex pipiens pallens (diptera: culicidae).xenorhabdusandphotorhabdusspp. (enterobacteriaceae) can synthesize and release secondary metabolites that play crucial roles in their pathogenicity by suppressing the immunity of target insects. the insect immunity contributes to defense against the pathogenicity ofbacillus thuringiensis(bt). this study tested a hypothesis that bacterial immunosuppresants could enhance the susceptibility of mosquitoes (aedes albopictusandculex pipiens pallens) to bt. three symbiotic bacteria [x. nematophila(xn), ...201627018440
ipm use with the deployment of a non-high dose bt pyramid and mitigation of resistance for western corn rootworm (diabrotica virgifera virgifera).recent detection of western corn rootworm resistance to bt (bacillus thuringiensis) corn prompted recommendations for the use of integrated pest management (ipm) with planting refuges to prolong the durability of bt technologies. we conducted a simulation experiment exploring the effectiveness of various ipm tools at extending durability of pyramided bt traits. results indicate that some ipm practices have greater merits than others. crop rotation was the most effective strategy, followed by inc ...201627018423
a black (white) hole in the global spread of gm cotton.bt (bacillus thuringiensis) cotton has been widely adopted, notably by smallholder farmers in developing countries. however, it has not been used in central asia, an important cotton-producing region. we discuss possible reasons and hypothesize that the most likely explanation is limited local demand for bt owing to low levels of pest infestation. this would imply that global bt cotton adoption rates may already be close to 100% when considering real demand for insect-resistant varieties.201627017312
transgenic rice expressing the cry2ax1 gene confers resistance to multiple lepidopteran pests.a chimeric bacillus thuringiensis toxin (bt) gene, cry2ax1was cloned in a bi-selectable marker free binary vector construct. the cry2ax1 gene, driven by the chrysanthemum rbcs1 promoter, was introduced into jk1044r, the restorer line (oryza sativa l. ssp. indica) of a notified commercially grown rice hybrid in india, by agrobacterium-mediated transformation. its effect against two major lepidopteran insect pests viz., yellow stem borer (ysb) scirpophaga incertulas, rice leaf folder (rlf) cnaphal ...201627017220
ingestion of bt corn pollen containing cry1ab/2aj or cry1ac does not harm propylea japonica larvae.propylea japonica (thunberg) (coleoptera: coccinellidae) is a prevalent pollen consumer in corn fields and is therefore exposed to insecticidal proteins contained in the pollen of insect-resistant transgenic corn cultivars expressing cry proteins derived from bacillus thuringiensis (bt). in the present study, the potential effect of cry1ab/2aj- or cry1ac-containing transgenic bt corn pollen on the fitness of p. japonica larvae was evaluated. the results show that the larval developmental time wa ...201627005950
a novel metalloproteinase virulence factor is involved in bacillus thuringiensis pathogenesis in nematodes and insects.the gram-positive soil bacterium bacillus thuringiensis has been developed as the leading microbial insecticide for years. the pathogenesis of b. thuringiensis requires common extracellular factors that depend on the plcr regulon, which regulates a large number of virulence factors; however, the precise role of many of these proteins is not known. in this study, we describe the complete lifecycle of a nematicidal b. thuringiensis strain in the free living nematode caenorhabditis elegans using in ...201626995589
comparison of susceptibility of chilo suppressalis and bombyx mori to five bacillus thuringiensis proteins.transformation of rice with genes encoding insecticidal cry proteins from bacillus thuringiensis (bt) should confer high resistance to target lepidopteran pests, such as chilo suppressalis, and low toxicity to non-target organisms, such as silkworm bombyx mori. five purified cry proteins that have been used for plant transformation were tested using dietary exposure assays. the susceptibility of c. suppressalis larvae to the five insecticidal proteins in the decreasing order was: cry1ca>cry1ab>c ...201626994840
daphnia magna negatively affected by chronic exposure to purified cry-toxins.cry-toxin genes originating from bacillus thuringiensis are inserted into genetically modified (gm) plants, often called bt-plants, to provide insect resistance to pests. significant amounts of bt-plant residues, and thus cry-toxins, will be shed to soil and aquatic environments. we exposed daphnia magna to purified cry1ab and cry2aa toxins for the full life-span of the animals. we used single toxins in different doses and combinations of toxins and roundup(®), another potential stressor on the ...201626993955
characterization of trypsin-like and chymotrypsin-like serine proteases from midgut of mythimna separata walker.two cdna sequences encoding a trypsin-like and a chymotrypsin-like serine protease (mst and msct, genbank accession nos. kp730443 and kp730444, respectively) were cloned from midgut of oriental armyworm, mythimna separata walker. multiple alignments revealed that the deduced amino acid sequences of mst and msct contained a serine protease catalytic motif gdsggpl and catalytic triads (his, asp, and ser). analyses of tissue and developmental expression of mst and msct showed that they were mainly ...201626988941
bacterial vegetative insecticidal proteins (vip) from entomopathogenic bacteria.entomopathogenic bacteria produce insecticidal proteins that accumulate in inclusion bodies or parasporal crystals (such as the cry and cyt proteins) as well as insecticidal proteins that are secreted into the culture medium. among the latter are the vip proteins, which are divided into four families according to their amino acid identity. the vip1 and vip2 proteins act as binary toxins and are toxic to some members of the coleoptera and hemiptera. the vip1 component is thought to bind to recept ...201626935135
no association between the use of bti for mosquito control and the dynamics of non-target aquatic invertebrates in french coastal and continental wetlands.the environmental safety of bacillus thuringiensis subsp. israelensis (bti) is still controversial, mainly because most of the previous field studies on its undesired effects were spatially limited and did not address the relationship between community similarity and application time and frequency. no general statement can therefore be drawn on the usage conditions of bti that insure protection of non-target organisms. the present study was conducted in eight sites distributed over the main geog ...201626930319
single amino acid insertions in extracellular loop 2 of bombyx mori abcc2 disrupt its receptor function for bacillus thuringiensis cry1ab and cry1ac but not cry1aa toxins.in a previous report, seven cry1ab-resistant strains were identified in the silkworm, bombyx mori; these strains were shown to have a tyrosine insertion at position 234 in extracellular loop 2 of the abc transporter c2 (bmabcc2). this insertion was confirmed to destroy the receptor function of bmabcc2 and confer the strains resistance against cry1ab and cry1ac. however, these strains were susceptible to cry1aa. in this report, we examined the mechanisms of the loss of receptor function of the tr ...201626928903
expression of an engineered synthetic cry2aa (d42/k63f/k64p) gene of bacillus thuringiensis in marker free transgenic tobacco facilitated full-protection from cotton leaf worm (s. littoralis) at very low concentration.emergence of resistant insects limits the sustainability of bacillus thuringiensis (bt) transgenic crop plants for insect management. beside this, the presence of unwanted marker gene(s) in the transgenic crops is also a major environmental and health concern. thus, development of marker free transgenic crop plants expressing a new class of toxin having a different mortality mechanism is necessary for resistance management. in a previous study, we generated an engineered cry2aa (d42/k63f/k64p) t ...201626925624
bacillus thuringiensis peptidoglycan hydrolase sleb171 involved in daughter cell separation during cell division.whole-genome analyses have revealed a putative cell wall hydrolase gene (sleb171) that constitutes an operon with two other genes (ypebandyhcn) of unknown function inbacillus thuringiensisbmb171. the putative sleb171 protein consists of 259 amino acids and has a molecular weight of 28.3 kda. gene disruption ofsleb171in the bmb171 genome causes the formation of long cell chains during the vegetative growth phase and delays spore formation and spore release, although it has no significant effect o ...201626922318
the use of aedes aegypti larvae attractants to enhance the effectiveness of larvicides.aedes aegypti (l.) is an important dengue, chikungunya, and yellow fever vector. immature stages of this species inhabit human-made containers placed in residential landscapes, and the application of larvicides inside containers that cannot be eliminated is still considered a priority in control programs. larvicidal efficacy is influenced by several factors, including the formulation used, the water quality, and the susceptibility of larvae, among others. if an attractant can be incorporated int ...201626922177
diffusible signal factor family signals provide a fitness advantage to xanthomonas campestris pv. campestris in interspecies competition.diffusible signal factor (dsf) represents a new class of widely conserved quorum sensing signals, which regulates various biological functions through intra- or interspecies signaling. the previous studies identified that there is an antagonistic interaction between xanthomonas and bacillus species bacteria in natural ecosystem, but the detailed molecular mechanism of interspecies competition is not clear. this study showed that xanthomonas campestris pv. campestris (xcc) interfered with morphol ...201626913592
cloning, characterization and expression of a novel haplotype cry2a-type gene from bacillus thuringiensis strain swk1, native to himalayan valley kashmir.bacillus thuringiensis (bt) is a gram positive bacterium which is effectively being used in pest management strategies as an eco-friendly bioinsecticide. in the present study a new cry2a gene was cloned from a promising indigenous b. thuringiensis swk1 strain previously characterized for its toxicity against spodoptera litura and helicoverpa armigera larvae. the nucleotide sequence of the cloned cry2a gene pointed out that the open reading frame has 1902 bases encoding a polypeptide of 634 amino ...201626906447
investigation of larvae digestive β-glucosidase and proteases of the tomato pest tuta absoluta for inhibiting the insect development.the tomato leaf miner tuta absoluta is one of the most devastating pests for tomato crops. digestive proteases and β-glucosidase enzymes were investigated using general and specific substrates and inhibitors. maximal β-glucosidase and proteolytic activities occurred at temperature and ph optima of 30 and 40°c, 5 and 10-11 unit of ph, respectively. zymogram analysis showed the presence of distinguished β-glucosidase exhibiting a specific activity of about 183 ± 15 µmol min-1 mg-1. in vitro inhibi ...201626898349
effect of adding amino acids residues in n- and c-terminus of vip3aa16 (l121i) toxin.to study the importance of n- and c-terminus of bacillus thuringiensis vip3aa16 (l121i) toxin (88 kda), a number of mutants were generated. the addition of two (2r: rs) or eleven (11r: rsrpghhhhhh) amino acid residues at the vip3aa16 (l121i) c-terminus allowed to an unappropriated folding illustrated by the abundant presence of the 62 kda proteolytic form. the produced vip3aa16 (l121i) full length form was less detected when increasing the number of amino acids residues in the c-terminus. bioass ...201626876111
novel actin filaments from bacillus thuringiensis form nanotubules for plasmid dna segregation.here we report the discovery of a bacterial dna-segregating actin-like protein (btparm) from bacillus thuringiensis, which forms novel antiparallel, two-stranded, supercoiled, nonpolar helical filaments, as determined by electron microscopy. the btparm filament features of supercoiling and forming antiparallel double-strands are unique within the actin fold superfamily, and entirely different to the straight, double-stranded, polar helical filaments of all other known parms and of eukaryotic f-a ...201626873105
resistance to bacillus thuringiensis mediated by an abc transporter mutation increases susceptibility to toxins from other bacteria in an invasive insect.evolution of pest resistance reduces the efficacy of insecticidal proteins from the gram-positive bacterium bacillus thuringiensis (bt) used widely in sprays and transgenic crops. recent efforts to delay pest adaptation to bt crops focus primarily on combinations of two or more bt toxins that kill the same pest, but this approach is often compromised because resistance to one bt toxin causes cross-resistance to others. thus, integration of bt toxins with alternative controls that do not exhibit ...201626872031
effect of crop plants on fitness costs associated with resistance to bacillus thuringiensis toxins cry1ac and cry2ab in cabbage loopers.fitness costs associated with resistance to bacillus thuringiensis (bt) toxins critically impact the development of resistance in insect populations. in this study, the fitness costs in trichoplusia ni strains associated with two genetically independent resistance mechanisms to bt toxins cry1ac and cry2ab, individually and in combination, on four crop plants (cabbage, cotton, tobacco and tomato) were analyzed, in comparison with their near-isogenic susceptible strain. the net reproductive rate ( ...201626868936
bacillus thuringiensis b1(2015b) is a gram-positive bacteria able to degrade naproxen and ibuprofen.a gram-positive bacterium, designated as strain b1(2015b), was isolated from the soil of the chemical factory "organika-azot" in jaworzno, poland. on the basis of 16s rrna gene sequence analysis, the isolated strain was classified as a bacillus thuringiensis species. strain b1(2015b) is able to degrade ibuprofen and naproxen, however, these compounds are not sufficient carbon sources for this strain. in the presence of glucose, bacillus thuringiensis b1(2015b) degrades ibuprofen and naproxen wit ...201727358504
selection and characterization of bacillus thuringiensis (berliner) (eubacteriales: bacillaceae) strains for ecdytolopha aurantiana (lima) (lepidoptera: tortricidae) control.the citrus fruit borer, ecdytolopha aurantiana (lima, 1927) (lepidoptera: tortricidae), is responsible for major losses to the citrus industry because it causes rot and drop of fruits. the current study aimed to select and characterize bacillus thuringiensis (berliner, 1911) strains toxic to e. aurantiana. for this purpose, 47 b. thuringiensis strains were evaluated in selective bioassays using first instar larvae of e. aurantiana. the lethal concentration (lc50) of the most toxic strains was es ...201727406593
microbial biofertilizer decreases nicotine content by improving soil nitrogen supply.biofertilizers have been widely used in many countries for their benefit to soil biological and physicochemical properties. a new microbial biofertilizer containing phanerochaete chrysosporium and bacillus thuringiensis was prepared to decrease nicotine content in tobacco leaves by regulating soil nitrogen supply. soil no3(-)-n, nh4(+)-n, nitrogen supply-related enzyme activities, and nitrogen accumulation in plant leaves throughout the growing period were investigated to explore the mechanism o ...201727439003
conditions for homogeneous preparation of stable monomeric and oligomeric forms of activated vip3a toxin from bacillus thuringiensis.bacillus thuringiensis vegetative insecticidal proteins like vip3a have been used for crop protection and to delay resistance to existing insecticidal cry toxins. however, little is known about vip3a's behavior or its mechanism of action, and a structural model is required. herein, in an effort to facilitate future crystallization and functional studies, we have used the orthogonal biophysical techniques of light scattering and sedimentation to analyze the aggregation behavior and stability of t ...201727473845
multi stakeholders' attitudes toward bt rice in southwest, iran: application of tpb and multi attribute models.organisms that have been genetically engineered and modified (gm) are referred to as genetically modified organisms (gmos). bt crops are plants that have been genetically modified to produce certain proteins from the soil bacteria bacillus thuringiensis (bt), which makes these plants resistant to certain lepidopteran and coleopteran species. genetically modified (gm) rice was produced in 2006 by iranian researchers from tarom mowla'ii and has since been called 'bt rice'. as rice is an important ...201727498978
the use of structural modelling to infer structure and function in biocontrol agents.homology modelling can provide important insights into the structures of proteins when a related protein structure has already been solved. however, for many proteins, including a number of invertebrate-active toxins and accessory proteins, no such templates exist. in these cases, techniques of ab initio, template-independent modelling can be employed to generate models that may give insight into structure and function. in this overview, examples of both the problems and the potential benefits o ...201727498218
safety considerations derived from cry34ab1/cry35ab1 structure and function.insecticidal proteins developed for in-plant protection against crop pests undergo extensive safety testing during the product development process. safety considerations for insecticidal proteins expressed in crops follow recommended, science-based guidelines and specific studies are conducted on a case by case basis. corn events expressing bacillus thuringiensis (bt) cry34ab1 and cry35ab1 were developed to protect maize from diabrotica virgifera virgifera (western corn rootworm) feeding damage. ...201727480405
specificity determinants for cry insecticidal proteins: insights from their mode of action.insecticidal proteins from the bacterium bacillus thuringiensis (bt) are used as active components of biopesticides and as plant incorporated protectants in transgenic crops. one of the most relevant attributes of these bt protein-based insecticidal technologies is their high specificity, which assures lack of detrimental effects on non-target insects, vertebrates and the environment. the identification of specificity determinants in bt insecticidal proteins could guide risk assessment for novel ...201727480404
structural classification of insecticidal proteins - towards an in silico characterisation of novel toxins.the increasing rate of discovery of new toxins with potential for the control of invertebrate pests through next generation sequencing, presents challenges for the identification of the best candidates for further development. a consideration of structural similarities between the different toxins suggest that they may be functionally less diverse than their low sequence similarities might predict. this is encouraging from the prospective of being able to use computational tools to predict toxin ...201727480403
evaluation of the recovery rate of different swabs for microbial environmental monitoring.contact plates, dipslides, and swabs are used for the microbiological monitoring of surfaces in controlled environments such as pharmaceutical clean rooms. in the present study, three different swab types using two different methods (direct streaking on agar versus elution followed by membrane filtration) were evaluated. in a first study, representative surfaces in pharmaceutical clean rooms were artificially inoculated using three different environmental strains (in vitro study). in a second st ...201727516491
towards novel cry toxins with enhanced toxicity/broader: a new chimeric cry4ba / cry1ac toxin.attempts have been made to express or to merge different cry proteins in order to enhance toxic effects against various insects. cry1a proteins of bacillus thuringiensis form a typical bipyramidal parasporal crystal and their protoxins contain a highly conserved c-terminal region. a chimerical gene, called cry(4ba-1ac), formed by a fusion of the n-terminus part of cry4ba and the c-terminus part of cry1ac, was constructed. its transformation to an acrystalliferous b. thuringiensis strain showed t ...201727538933
parasporins 1 and 2: their structure and activity.parasporins are novel protein toxins preferentially cytotoxic against human cancer cells. they are obtained from parasporal inclusions of bacillus thuringiensis and, accordingly, are considered congeners of the insecticidal cry toxins. two types of parasporins have been identified: the three-domain cry toxin type and the β-pore-forming-toxin (β-pft) type. crystal structures of representative members of the two types, ps1aa1 and ps2aa1, have been determined and compared with those of well-studied ...201727769815
insecticidal spectrum and mode of action of the bacillus thuringiensis vip3ca insecticidal protein.the vip3ca protein, discovered in a screening of spanish collections of bacillus thuringiensis, was known to be toxic to chrysodeixis chalcites, mamestra brassicae and trichoplusia ni. in the present study, its activity has been tested with additional insect species and we found that cydia pomonella is moderately susceptible to this protein. vip3ca (of approximately 90kda) was processed to an approximately 70kda protein when incubated with midgut juice in all tested species. the kinetics of prot ...201727756652
immunological mechanisms of synergy between fungus metarhizium robertsii and bacteria bacillus thuringiensis ssp. morrisoni on colorado potato beetle larvae.the synergistic effect between the entomopathogenic fungus metarhizium robertsii and a sublethal dose of the bacterium bacillus thuringiensis ssp. morrisoni var. tenebrionis was studied in terms of immune defense reactions and detoxification system activity of the colorado potato beetle, leptinotarsa decemlineata, fourth instar larvae. bacterial infection led to more rapid germination of fungal conidia on integuments. we found a significant decrease of cellular immunity parameters, including tot ...201727751890
how well will stacked transgenic pest/herbicide resistances delay pests from evolving resistance?resistance has evolved to single transgenic traits engineered into crops for arthropod and herbicide resistances, and can be expected to evolve to the more recently introduced pathogen resistances. combining transgenes against the same target pest is being promoted as the solution to the problem. this solution will work if used pre-emptively, but where resistance has evolved to one member of a stack, resistance should easily evolve for the second gene in most cases. we propose and elaborate crit ...201727598030
rapid thermostabilization of bacillus thuringiensis serovar konkukian 97-27 dehydroshikimate dehydratase through a structure-based enzyme design and whole cell activity assay.thermostabilization of an enzyme with complete retention of catalytic efficiency was demonstrated on recombinant 3-dehydroshikimate dehydratase (dhsase or wtasbf) from bacillus thuringiensis serovar konkukian 97-27 (hereafter, b. thuringiensis 97-27). the wtasbf is relatively unstable at 37 °c, in vitro (t1/2(37) = 15 min), in the absence of divalent metal. we adopted a structure-based design to identify stabilizing mutations and created a combinatorial library based upon predicted mutations at ...201727548779
toxicity of cry1a toxins from bacillus thuringiensis to cf1 cells does not involve activation of adenylate cyclase/pka signaling pathway.bacillus thuringiensis (bt) bacteria produce cry toxins that are able to kill insect pests. different models explaining the mode of action of these toxins have been proposed. the pore formation model proposes that the toxin creates pores in the membrane of the larval midgut cells after interaction with different receptors such as cadherin, aminopeptidase n and alkaline phosphatase and that this pore formation activity is responsible for the toxicity of these proteins. the alternative model propo ...201727867074
biosterilant effects of bacillus thuringiensis kurstaki hd-73 extract on male wistar albino rats.chemosterilants have long been used in sterilization programs for managing pet, stray, and wild animals but adverse effects such as trauma, incomplete responses to treatment, and complete abolition of gonadal sources of testosterone often occurs. this study describes the biosterilant effects of administering three doses of bacillus thuringiensis kurstaki hd-73 (bt 5, 50, and 250 mg/kg; 20 rats/dose) extract in adult male wistar albino rats on testicular parameters, function, histology, and a num ...201727865415
glycan region of gpi anchored-protein is required for cytocidal oligomerization of an anticancer parasporin-2, cry46aa1 protein, from bacillus thuringiensis strain a1547.parasporin-2 (ps2), alternatively named cry46aa1, an anticancer protein derived from bacillus thuringiensis strain a1547, causes specific cell damage via ps2 oligomerization in the cell membrane. although ps2 requires glycosylphosphatidylinositol (gpi)-anchored proteins for its cytocidal action, their precise role is unknown. here, we report that the glycan of gpi induces ps2 oligomerization, which causes cell death. cytotoxicity, cell-binding and oligomerization of the toxin were not observed i ...201727863961
ephestia kuehniella tolerance to bacillus thuringiensis cry1aa is associated with reduced oligomer formation.the basis of the different susceptibility of ephestia kuehniella to the cry1aa and cry1ac δ-endotoxins from bacillus thuringiensis kurstaki bns3 was studied. both toxins bound specifically to the bbmv of e. kuehniella. the result of the ligand blot showed that cry1ac bound to three putative receptors of about 100, 65 and 80 kda and cry1aa interacted only with a 100 kda protein. pronase digestion of the bbmv-bound toxins was used to analyze the toxin insertion. both toxins inserted into the bbmv ...201727888109
the domain ii loops of bacillus thuringiensis cry1aa form an overlapping interaction site for two bombyx mori larvae functional receptors, abc transporter c2 and cadherin-like receptor.information about the receptor-interaction region of cry toxins, insecticidal proteins produced by bacillus thuringiensis, is needed to elucidate the mode of action of cry toxins and improve their toxicity through protein engineering. we analyzed the interaction sites on cry1aa with abc transporter c2 (abcc2), one of the most important cry1a toxin receptors. a competitive binding assay revealed that the bombyx mori abcc2 (bmabcc2) cry1a binding site was the same as the btr175 binding site, sugge ...201727888075
interactions among triphenyltin degradation, phospholipid synthesis and membrane characteristics of bacillus thuringiensis in the presence of d-malic acid.degradation pathway and surface biosorption of triphenyltin (tpt) by effective microbes have been investigated in the past. however, unclear interactions among membrane components and tpt binding and transport are still obstacles to understanding tpt biotransformation. to reveal the mechanism involved, the phospholipid expression, membrane potential, cellular mechanism and molecular dynamics between tpt and fatty acids (fas) during the tpt degradation process in the presence of d-malic acid (dma ...201727886543
dr. alois huger - laying the foundations for an integrated insect pathology.dr. rer. nat. alois m. huger had a long and distinguished career at the institut für biologische schädlingsbekämpfung (institute for biological pest control) darmstadt, germany, where he became one of the world's leading insect pathologists. he applied his experience and understanding of insect tissues and specialist skills in microscopy to diagnosis and elucidation of the pathology of insect diseases. during his career he discovered the oryctes nudivirus and bacillus thuringiensis subsp. tenebr ...201727871814
validation of adam10 metalloprotease as a bacillus thuringiensis cry3aa toxin functional receptor in colorado potato beetle (leptinotarsa decemlineata).bacillus thuringiensis parasporal crystal proteins (cry proteins) are insecticidal pore-forming toxins that bind to specific receptor molecules on the brush border membrane of susceptible insect midgut cells to exert their toxic action. in the colorado potato beetle (cpb), a coleopteran pest, we previously proposed that interaction of cry3aa toxin with a cpb adam10 metalloprotease is an essential part of the mode of action of this toxin. here, we annotated the gene sequence encoding an adam10 me ...201727918112
co-metabolism of substrates by bacillus thuringiensis regulates polyhydroxyalkanoate co-polymer composition.polyhydroxyalkanoate (pha) production by bacillus thuringiensis egu45 was studied by co-metabolism of crude glycerol (cg) (1%, v/v), glucose (0.05-0.5%, w/v) and propionic acid (0.05-0.5%, v/v) under batch (shake flask) culture conditions. glycerol+pa combination resulted in 15-100mg/l pha co-polymers with a hv content of 33-81mol%. the addition of nh4cl (0.5%, w/v) to cg+pa enhanced pha production by 1.55-fold, with a hv content of 58-70mol%. the time period of incubation of pa to the feed: cg+ ...201727914782
water influx via aquaporin directly determines necrotic cell death induced by the bacillus thuringiensis cry toxin.the bacillus thuringiensis cry toxin causes swelling and necrosis in insect cells, but the route(s) and significance of the water influx involved in its cytotoxicity are unclear. here, we assessed the role of aquaporins (aqps), known as water channels, in cry toxin intoxication. an aqp inhibitor did not interfere with any known process to form the toxin pore, but it diminished the cell swelling and loss of membrane integrity induced by the cry toxin. overexpression of aqps facilitated water infl ...201727914170
response of three cyprinid fish species to the scavenger deterrent factor produced by the mutualistic bacteria associated with entomopathogenic nematodes.the symbiotic bacteria, photorhabdus and xenorhabdus associated with entomopathogenic nematodes (epns) in the genera heterorhabditis and steinernema, respectively, produce a compound(s) called the scavenging deterrent factor (sdf). sdf deters a number of terrestrial insect scavengers and predators and one bird species from feeding on host insects killed by the nematode-bacterium complex but has not been tested against aquatic vertebrates. moreover, the heterorhabditis-photorhabdus association is ...201727908637
triphenyltin degradation and proteomic response by an engineered escherichia coli expressing cytochrome p450 enzyme.although triphenyltin (tpt) degradation pathway has been determined, information about the enzyme and protein networks involved was severely limited. to this end, a cytochrome p450 hydroxylase (cyp450) gene from bacillus thuringiensis was cloned and expressed in escherichia coli bl21 (de3), namely e. coli pet32a-cyp450, whose dosage at 1gl(-1) could degrade 54.6% tpt at 1mgl(-1) within 6 d through attacking the carbon-tin bonds of tpt by cyp450. sequence analysis verified that the cyp450 gene ha ...201727907843
improved catalytic and antifungal activities of bacillus thuringiensis cells with surface display of chi9602δsp.the cell-surface display of chitinase chi9602δsp was constructed on bacillus thuringiensis bmb171 by using two repeat n-terminal regions of autolysin (mbgn)2 as the anchoring motif. this study aimed to prepare a chitinolytic whole-cell b. thuringiensis biocatalyst with improved catalytic and antifungal activities.201727782360
genetic hitchhiking and resistance evolution to transgenic bt toxins: insights from the african stalk borer busseola fusca (noctuidae).since transgenic crops expressing bacillus thuringiensis (bt) toxins were first released, resistance evolution leading to failure in control of pests populations has been observed in a number of species. field resistance of the moth busseola fusca was acknowledged 8 years after bt maize was introduced in south africa. since then, field resistance of this corn borer has been observed at several locations, raising questions about the nature, distribution and dynamics of the resistance trait. using ...201727782120
ultrasensitive sers detection of bacillus thuringiensis special gene based on au@ag nrs and magnetic beads.highly sensitive and selective detection of specific dna sequences is of great importance in clinical diagnosis, environmental and food monitoring, but it still remains challenges to develop a facile method for real sample detection in aqueous solution. here, a simple and recyclable surface enhanced raman scattering (sers) sensor was constructed for bacillus thuringiensis (bt) special gene fragment detection by fe3o4 magnetic beads (mbs) and au-ag core-shell nanorods (au@ag nrs). a hairpin dna w ...201727839730
establishment of a sensitive time-resolved fluoroimmunoassay for detection of bacillus thuringiensis cry1ie toxin based nanobody from a phage display library.cry1ie toxin was an insect-resistant protein used in genetically modified crops (gmc). in this study, a large human vh gene nanobodies phage displayed library was employed to select anti-cry1ie toxin antibody by affinity panning. after 5 rounds of panning, total 12 positive monoclonal phage particles were obtained. one of the identified positive phage nanobody was expressed in e.coli bl21 and the purified protein was indicated as a molecular mass of approximately 20 kda by sodium dodecyl sulfate ...201727838242
comparison of chito-oligosaccharide production from three different colloidal chitosans using the endochitonsanolytic system of bacillus thuringiensis.bacillus thuringiensis is a nonhuman pathogen bacterium that is used as a fungal and insect biocontrol agent. because of its environmental interaction, it possesses several extracellular enzymes that are able to degrade chitin and chitosan, two of the most important polymers because of their application in numerous fields. however, in recent years, it has been observed that oligosaccharides from the enzymatic degradation of chitosan have important benefits for human health. comparison and explor ...201727830993
rnai in the striped stem borer, chilo suppressalis, establishes a functional role for aminopeptidase n in cry1ab intoxication.the striped stem borer, chilo suppressalis, is a major target pest of transgenic rice expressing the cry1ab protein from the bacterium bacillus thuringiensis (bt) in china. evolution of resistance in this pest is a major threat to the durability of bt rice. since bt exerts its activity through binding to specific receptors in the midgut of target insects, identification of functional cry1ab receptors in the midgut of c. suppressalis larvae is crucial to evaluate potential resistance mechanisms a ...201727823898
eco-toxicological risk and impact of pesticides on important parasitoids of cabbage butterflies in cruciferous ecosystem.eco-toxicological risk and impact of pesticides was estimated on three important parasitoids of butterflies viz., hyposoter ebeninus, cotesia glomerata and pteromalus puparum. four commonly used pesticides were evaluated using standard protocol (of iobc/wprs-group). in laboratory tests, the survival of the female wasps decreased significantly on fresh contact and ingestion of deltamethrin, spinosad and azadirachtin; whereas bacillus thuringiensis var kurstaki (btk) was found harmless pesticide. ...201727810537
[characterization and cloning of the cry2a gene from indigenous isolates of bacillus thuringiensis].discovery of novel cry genes of bacillus thuringiensis (bt) with higher toxicity is important for the development of transgenic bt crops resistant to target pests. two new indigenous isolates of bt were characterized for their colony type, crystal inclusion and toxicity with helicoverpa armigera hubner and spodoptera litura linn. screening of cry2a genes from the two new isolates of bt, t30 and t48, by pcr with cry2a family primers showed the presence of cry2a genes only in the isolate t30. furt ...201726299858
isolation and characterization of a new bacillus thuringiensis strain with a promising toxicity against lepidopteran pests.insecticides derived from bacillus thuringiensis are gaining worldwide importance as environmentally desirable alternatives to chemicals for the control of pests in public health and agriculture. isolation and characterization of new strains with higher and broader spectrum of activity is an ever growing field. in the present work, a novel tunisian b. thuringiensis isolate named blb459 was characterized and electrophoresis assay showed that among a collection of 200 b. thuringiensis strains, the ...201727242138
microbiology of cooked and dried edible mediterranean field crickets (gryllus bimaculatus) and superworms (zophobas atratus) submitted to four different heating treatments.to increase the shelf life of edible insects, modern techniques (e.g. freeze-drying) add to the traditional methods (degutting, boiling, sun-drying or roasting). however, microorganisms become inactivated rather than being killed, and when rehydrated, many return to vegetative stadia. crickets (gryllus bimaculatus) and superworms (zophobas atratus) were submitted to four different drying techniques (t1 = 10' cooking, 24 h drying at 60℃; t2 = 10' cooking, 24 h drying at 80℃; t3 = 30' cooking, 12  ...201727235993
the sequence, structural, and functional diversity within a protein family and implications for specificity and safety: the case for etx_mtx2 insecticidal proteins.the need for sustainable insect pest control is driving the investigation and discovery of insecticidal proteins outside of the typical 3-domain cry protein family from bacillus thuringiensis (bt). examples include cry35 and cry51 that belong to protein families (toxin_10, etx_mtx2) sharing a common β-pore forming structure and function with known mammalian toxins such as epsilon toxin (etx). although β-pore forming proteins are related to mammalian toxins, there are key differences in sequence ...201727235983
fitness costs and stability of cry1fa resistance in brazilian populations of spodoptera frugiperda.the presence of fitness costs of resistance to bacillus thuringiensis (bt) insecticidal proteins in insect populations may delay or even reverse the local selection of insect resistance to bt transgenic crops, and deserves rigorous investigation. here we assessed the fitness costs associated with cry1fa resistance in two strains of fall armyworm, spodoptera frugiperda (lepidoptera: noctuidae), derived from field collections in different brazilian regions and further selected in the laboratory fo ...201727147125
expression of cry1ab gene from a novel bacillus thuringiensis strain sy49-1 active on pest insects.in this study, the cry1ab gene of previously characterized and lepidoptera-, diptera-, and coleoptera-active bacillus thuringiensis sy49-1 strain was cloned, expressed and individually tested on ephestia kuehniella (lepidoptera: pyralidae) and plodia interpunctella (lepidoptera: pyralidae) larvae. pet-cry1ab plasmids were constructed by ligating the cry1ab into pet28a (+) expression vector. constructed plasmids were transferred to an escherichia coli bl21 (de3) strain rendered competent with cac ...201727143037
proteomic analysis of cry2aa-binding proteins and their receptor function in spodoptera exigua.the bacterium bacillus thuringiensis produces crystal (cry) proteins that are toxic to a diverse range of insects. transgenic crops that produce bt cry proteins are grown worldwide because of their improved resistance to insect pests. although bt "pyramid" cotton that produces both cry1a and cry2a is predicted to be more resistant to several lepidopteran pests, including spodoptera exigua, than plants that produce cry1ac alone, the mechanisms responsible for the toxicity of cry2aa in s. exigua a ...201728067269
killing the spores of bacillus species by molecular iodine.to determine the responses of spores of bacillus subtilis and bacillus anthracis surrogate bacillus thuringiensis al hakam to i2 treatment.201727696602
characterization of yersinia species by protein profiling using automated microfluidic capillary electrophoresis.yersinia pestis is a biological agent of high risk to national security due to its ability to be easily disseminated and transmitted among humans. if y. pestis was to be utilized in a deliberate disease outbreak it would be essential to rapidly and accurately identify the agent. current identification methods for yersinia species are limited by their reliance on cultivation, the time taken to achieve results and/or the use of protocols that are not amenable for field use. faster identification m ...201728019002
dynamics of bacterial class bacilli in the deepest valley lake of kashmir-the manasbal lake.in recognition of the importance of bacteria as ecological indicators of the aquatic systems a comprehensive and systematic analysis was carried out on manasbal lake, the deepest spring fed valley lake of kashmir. the main objective envisaged was to analyze bacterial community composition (bcc) and for this purpose systematic and regular sampling of waters from ten different sampling stations, predetermined in the lake according to differences in degree of human interference and also as zones of ...201728087491
bacillus spp. isolated from puba as a source of biosurfactants and antimicrobial lipopeptides.several products of industrial interest are produced by bacillus, including enzymes, antibiotics, amino acids, insecticides, biosurfactants and bacteriocins. this study aimed to investigate the potential of two bacterial isolates (p5 and c3) from puba, a regional fermentation product from cassava, to produce multiple substances with antimicrobial and surface active properties. phylogenetic analyses showed close relation of isolates p5 and c3 with bacillus amyloliquefaciens and bacillus thuringie ...201728197131
combinatorial effect of bacillus amyloliquefaciens ag1 biosurfactant and bacillus thuringiensis vip3aa16 toxin on spodoptera littoralis larvae.spodoptera littoralis, one of the most serious and destructive agricultural pests in the world, is very susceptible to vip3 toxin. in order to develop a new efficient bioinsecticide and to prevent the development of resistance by the target pest, insecticidal activity of biosurfactant produced by bacillus amyloliquefaciens ag1 was evaluated against s. littoralis. bioassays revealed the susceptibility of the first instar larvae of this pest to ag1 biosurfactant with an lc50 of 245ng/cm(2). moreov ...201728093209
the detection and quantification of bacillus thuringiensis spores from soil and swabs using quantitative pcr as a model system for routine diagnostics of bacillus anthracis.to optimize the dna isolation for the routine detection and quantification of bacillary spores in soil and swabs. the procedure is primarily intended for diagnostics of bacillus anthracis spores, but due to its high pathogenicity b. thuringiensis served as its surrogate organism.201728294483
construction of bacillus thuringiensis simulant strains suitable for environmental release.for a surrogate bacterium to be used in outdoor studies, it is important to consider environmental and human safety, and ease of detection. recently, bacillus thuringiensis, a popular bioinsecticide bacterium, is gaining attention as a surrogate bacterium for its use in biodefense. in this study, we constructed simulant strains of b. thuringiensis with enhanced characteristics for environmental studies. through transposon mutagenesis, pigment genes were inserted into the chromosome, producing ye ...201728258144
re-aerosolization of bacillus thuringiensis spores from concrete and turf.spores of bacillus anthracis deposited on surfaces can become airborne again as a result of air currents and mechanical forces. as such they are a potential source of infection by inhalation. spores of bacillus thuringiensis were used to quantify this phenomenon in a simulation of outdoor conditions. concrete and turf surfaces were inoculated by aerosol to produce high spore densities (greater than 1 x 10(9) cfu m(-2) ) which were then subjected to the passage of air at 10 ms(-1) with and withou ...201728256003
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