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risk assessment for helicoverpa zea (lepidoptera: noctuidae) resistance on dual-gene versus single-gene corn.recent environmental protection agency (epa) decisions regarding resistance management in bt-cropping systems have prompted concern in some experts that dual-gene bt-corn (cryla.105 and cry2ab2 toxins) may result in more rapid selection for resistance in helicoverpa zea (boddie) than single-gene bacillus thuringiensis (bt)-corn (crylab toxin). the concern is that bt-toxin longevity could be significantly reduced with recent adoption of a natural refuge for dual-gene bt-cotton (crylac and cry2ab2 ...201323448055
investigating alternatives to traditional insecticides: effectiveness of entomopathogenic fungi and bacillus thuringiensis against citrus thrips and avocado thrips (thysanoptera: thripidae).citrus thrips, scirtothrips citri (moulton) (thysanoptera: thripidae), is a plant-feeding pest most widely recognized for causing damage to citrus (citrus spp. l. [rutaceae]) and mango (mangifera indica l. [anacardiaceae]) fruits. this insect has recently broadened its known host range to become a significant pest of california grown blueberries. avocado thrips, scirtothrips. perseae nakahara (thysanoptera: thripidae), is a recent, invasive pest of california avocados, persea americana mill. (la ...201323448016
the effect of gamma sterilization on the insecticidal toxicity of engineered and conventional bacillus thuringiensis strains.this study evaluates the effect of gamma radiation on the spore activity, toxicity, and crystal structures of two engineered bacillus thuringiensis (bt) strains, tnx and tny, and the reference bt strain hd-1. we attempted to identify dosages of cobalt-60 gamma radiation that would inactivate bt spores but not affect its toxicity. in the radiation dosage range of 10-15 kilogray, no viable spore formation and no significant reduction of the efficiency of bt against lepidopteran larvae were observe ...201323448012
the atp-binding cassette transporter subfamily c member 2 in bombyx mori larvae is a functional receptor for cry toxins from bacillus thuringiensis.bacillus thuringiensis is the most widely used biopesticide, and its cry toxin genes are essential transgenes for the generation of insect-resistant transgenic crops. recent reports have suggested that atp-binding cassette transporter subfamily c2 (abcc2) proteins are implicated in cry intoxication, and that a single amino acid insertion results in high levels of resistance to cry1 toxins. however, there is currently no available direct evidence of functional interactions between abcc2 and cry t ...201323432933
[susceptibility of aedes aegypti (l.) strains from havana to a bacillus thuringiensis var. israelensis].the integration of chemical and biological methods is one of the strategies for the vector control, due to the existing environmental problems and the concerns of the community as a result of the synthetic organic insecticide actions. the bacterium called bacillus thuringiensis var. israelensis in liquid formulation has been widely used in the vector control programs in several countries and has shown high efficacy at lab in cuba.201323424808
[influence of biotic factors on the efficacy of bacillus thuringiensis var. israelensis against aedes aegypti (diptera: culicidae)].bacillus thuringiensis h-14 has shown high efficacy on aedes aegypti larvae. but a number of factors could affect its effectiveness. knowing these factors is of vital importance for improving the application parameters in real conditions in order to guarantee the treatment's efficiency and to reduce environmental impact.201323424800
managing the sugarcane borer, diatraea saccharalis, and corn earworm, helicoverpa zea, using bt corn and insecticide treatments.the sugarcane borer, diatraea saccharalis (fabricius) (lepidoptera: crambidae) and the corn earworm, helicoverpa zea (boddie) (lepidoptera: noctuidae), are important pests of corn in brazil and have not been successfully managed, because of the difficulty of managing them with pesticides. the objective of this study was to evaluate the effect of bt corn mon810, transformed with a gene from bacillus thuringiensis berliner (bacillales: bacillaceae) insecticide seed treatment, and foliar insecticid ...201324735131
crustacean biodiversity as an important factor for mosquito larval control.newly established ponds, which are highly dynamic systems with changing levels of biological interactions among species, are common larval mosquito habitats. we investigated the impact of crustacean abundance and taxa diversity on mosquito oviposition and larval development. the effects of the biological larvicide bacillus thuringiensis israelensis (bti) on mosquito larvae were monitored according to fluctuations in crustacean communities. populations of the mosquito culex pipiens colonized arti ...201324581370
assessment of a direct application of two bacillus thuringiensis israelensis formulations for immediate and residual control of aedes albopictus.the bacterial agent bacillus thuringiensis israelensis (bti) is a highly effective larvicide against various medically important mosquito and black fly vector species. recent formulations of this powerful larvicidal tool have been evaluated for their field efficacy in integrated mosquito management programs. laboratory and controlled-condition trials have indicated long periods of residual efficacy, whereas field persistence is often much lower in duration. we investigated the residual persisten ...201324551974
application of statistical experimental design for optimisation of bioinsecticides production by sporeless bacillus thuringiensis strain on cheap medium.in order to overproduce bioinsecticides production by a sporeless bacillus thuringiensis strain, an optimal composition of a cheap medium was defined using a response surface methodology. in a first step, a plackett-burman design used to evaluate the effects of eight medium components on delta-endotoxin production showed that starch, soya bean and sodium chloride exhibited significant effects on bioinsecticides production. in a second step, these parameters were selected for further optimisation ...201324516462
dominant resistance to bt cotton and minor cross-resistance to bt toxin cry2ab in cotton bollworm from china.evolution of resistance by insect pests threatens the long-term benefits of transgenic crops that produce insecticidal proteins from bacillus thuringiensis (bt). previous work has detected increases in the frequency of resistance to bt toxin cry1ac in populations of cotton bollworm, helicoverpa armigera, from northern china where bt cotton producing cry1ac has been grown extensively for more than a decade. confirming that trend, we report evidence from 2011 showing that the percentage of individ ...201324478804
effect of midgut proteolytic activity on susceptibility of lepidopteran larvae to bacillus thuringiensis subsp. kurstaki.bacillus thuringiensis (bt) is the most effective microbial control agent for controlling numerous species from different insect orders. all subspecies and strains of b. thuringiensis can produce a spore and a crystalline parasporal body. this crystal which contains proteinaceous protoxins is dissolved in the alkaline midgut, the resulting molecule is then cleaved and activated by proteolytic enzymes and acts as a toxin. an interesting aspect of this activation process is that variations in midg ...201324474937
evaluation of tolerance to bacillus thuringiensis toxins among laboratory-reared western bean cutworm (lepidoptera: noctuidae).the western bean cutworm, striacosta albicosta (smith) (lepidoptera: noctuidae), is a destructive insect pest of dry beans and corn within its native range of western nebraska and eastern colorado. however, since the initiation of an eastward range expansion of s. albicosta in the late 1990s, economic damage has been observed in the midwest, and the species has now reached the atlantic coast and quebec. economic damage to corn occurs by larval feeding on ears, which is not controlled by commerci ...201324498749
optimization of bioinsecticides overproduction by bacillus thuringiensis subsp. kurstaki using linear regression.a multiple linear regression analyses were performed to screen for the significant factors simultaneously influencing production of deltaendotoxin, proteolytic activities and spore formation by a bacillus thuringiensis kurstaki strain. investigated factors included: ph of the medium, available oxygen and inoculum size. it was observed that oxygen availability was the most influencing setting on both deltaendotoxins production and spores counts, followed by initial ph of the medium and inoculum s ...201324459834
production of polyhydroxyalkanoate co-polymer by bacillus thuringiensis.integrative processes for the production of bioenergy and biopolymers are gaining importance in recent years as alternatives to fossil fuels and synthetic plastics. in the present study, bacillus thuringiensis strain egu45 has been used to generate hydrogen (h2), polyhydroxybutyrate (phb) and new co-polymers (np). under batch culture conditions with 250 ml synthetic media, b. thuringiensis egu45 produced up to 0.58 mol h2/mol of glucose. effluent from the h2 production stage was incubated under ...201324426082
microbial dynamics and diversity of bacillus thuringiensis in textile effluent polluted and non-polluted rice field soils of orissa, india.microbial diversity was assessed in the soils of non-polluted rice fields of central rice research institute and choudwar, and textile effluent contaminated (about 30 years) rice fields of choudwar about 4 years after cessation of pollution. the soils contained 0.62-1.01 % organic c and 0.07-0.12 % total n, and measured 6.18-8.24 ph and 0.6-2.68 ms/cm eh which were more in the polluted choudwar soil. the microbial populations (×10(6) cfu/g soil) in the soils were: heterotrophs 1.21-10.9, spore f ...201324426074
molecular characterization of bacillus thuringiensis using rep-pcr.the genetic divergence of 65 strains of bacillus thuringiensis (bt) was determined using rep-pcr. based on the repetitive sequences the box primer was the most informative with 26 fragments, followed by eric (19) and rep (10), generating a total of 55 fragments. the dendogram shows that ten groups were formed when 45% was the average distance of the population: group 1 with 41,5% of the isolates, 33,8% of the isolates were distributed in other groups and 24,6% did not formed distinct group. 53,2 ...201324363981
bacillus thuringiensis poisoning related acute transverse myelitis. 201324340786
complete genome sequence of bacillus thuringiensis serovar israelensis strain hd-789.bacillus thuringiensis is an important microbial insecticide for controlling agricultural pests. we report the finished genome sequence of bacillus thuringiensis serovar israelensis strain hd-789, which contains genes encoding 7 parasporal crystals consisting of cry4aa3, cry4ba5 (2 genes), cry10aa3, cry11aa3, cry60ba3, and cry60aa3, plus 3 cyt toxin genes and 1 hemagglutinin gene.201324309743
complete genome of bacillus thuringiensis myophage spock.bacillus thuringiensis is a gram-positive, sporulating soil microbe with valuable pesticide-producing properties. the study of bacteriophages of b. thuringiensis could provide new biotechnological tools for the use of this bacterium. here, we present the complete annotated genome of spock, a myophage of b. thuringiensis, and describe its features.201324309729
domain wise docking analyses of the modular chitin binding protein cbp50 from bacillus thuringiensis serovar konkukian s4.this paper presents an in silico characterization of the chitin binding protein cbp50 from b. thuringiensis serovar konkukian s4 through homology modeling and molecular docking. the cbp50 has shown a modular structure containing an n-terminal cbm33 domain, two consecutive fibronectin-iii (fn-iii) like domains and a c-terminal cbm5 domain. the protein presented a unique modular structure which could not be modeled using ordinary procedures. so, domain wise modeling using modeller and docking anal ...201324307767
bacillus thuringiensis strain 199 can induce systemic resistance in tomato against fusarium wilt.the research work was performed to investigate the potential of bacillus thuringiensis strain 199 to induce systemic resistance in tomato against fusarium wilt. roots of two-week-old seedlings of tomato plants were primed with bacterial strain. after 10 days of transplantation, some pots of tomato seedlings were provided with inoculum of fusarium oxysporum lycopersici according to experimental design to induce disease. after 15 days of incubation period, plants challenged with f. oxysporum lycop ...201324294498
cloning and analysis of a large plasmid pbmb165 from bacillus thuringiensis revealed a novel plasmid organization.in this study, we report a rapid cloning strategy for large native plasmids via a contig linkage map by bac libraries. using this method, we cloned a large plasmid pbmb165 from bacillus thuringiensis serovar tenebrionis strain ybt-1765. complete sequencing showed that pbmb165 is 77,627 bp long with a gc-content of 35.36%, and contains 103 open reading frames (orfs). sequence analysis and comparison reveals that pbmb165 represents a novel plasmid organization: it mainly consists of a pxo2-like re ...201324312580
purification, biochemical characterization and self-assembled structure of a fengycin-like antifungal peptide from bacillus thuringiensis strain sm1.an antifungal lipopeptide fengycin, producing strain sm1 was isolated from farm land soil sample and identified as bacillus thuringiensis strain sm1 by using 16s rdna analysis. fengycin detected in the culture extract was further purified using hplc and showed a molecular mass of 1492.8 da by maldi-tof-ms analysis. purified fengycin was allowed to construct their self-assembled structure onto a hydrophobic surface showing a clear improvement of antibacterial activity. in self-assembly, fengycin ...201324312083
prohibitin, an essential protein for colorado potato beetle larval viability, is relevant to bacillus thuringiensis cry3aa toxicity.bacillus thuringienesis (bt) cry toxins constitute the most extensively used environmentally safe biopesticide and their mode of action relies on the interaction of the toxins with membrane proteins in the midgut of susceptible insects that mediate toxicity and insect specificity. therefore, identification of bt cry toxin interacting proteins in the midgut of target insects and understanding their role in toxicity is of great interest to exploit their insecticidal action. using ligand blot, we d ...201324267691
in silico modeling and functional interpretations of cry1ab15 toxin from bacillus thuringiensis btb-hm-16.the theoretical homology based structural model of cry1ab15 δ-endotoxin produced by bacillus thuringiensis btb-hm-16 was predicted using the cry1aa template (resolution 2.25 å). the cry1ab15 resembles the template structure by sharing a common three-domain extending conformation structure responsible for pore-forming and specificity determination. the novel structural differences found are the presence of β0 and α3, and the absence of α7b, β1a, α10a, α10b, β12, and α11a while α9 is located spati ...201324228249
green synthesis of silver nanoparticles, their characterization, application and antibacterial activity.our research focused on the production, characterization and application of silver nanoparticles (agnps), which can be utilized in biomedical research and environmental cleaning applications. we used an environmentally friendly extracellular biosynthetic technique for the production of the agnps. the reducing agents used to produce the nanoparticles were from aqueous extracts made from the leaves of various plants. synthesis of colloidal agnps was monitored by uv-visible spectroscopy. the uv-vis ...201324157517
cry1ac protoxin from bacillus thuringiensis promotes macrophage activation by upregulating cd80 and cd86 and by inducing il-6, mcp-1 and tnf-α cytokines.bacillus thuringiensis cry1ac protoxin (pcry1ac) is a promising mucosal adjuvant, but its action mechanism is unknown. we examined in vivo whether pcry1ac promotes the activation of macrophages in the peritoneum, spleen and mesenteric lymph nodes or in the lungs and bronchoalveolar lavage after intraperitoneal or intranasal pcry1ac administration, respectively, in balb/c mice. pcry1ac upregulated the costimulatory molecules cd80 and cd86 in these macrophages, but with distinct kinetics. in vitro ...201324157331
structural analysis and molecular dynamics simulations of novel δ-endotoxin cry1id from bacillus thuringiensis to pave the way for development of novel fusion proteins against insect pests of crops.the theoretical three-dimensional structure of a novel δ-endotoxin cry1id (81 kda) belonging to cry1i class, toxic to many of the lepidopteran pests has been investigated through comparative modeling. molecular dynamics (md) simulations was carried out to characterize its structural and dynamical features at 10 ns in explicit solvent using the gromacs version 4.5.4. finally the simulated model was validated by the saves, what if, metamqap, proq, modfold and molprobity servers. despite low sequen ...201324154610
dissipation of insecticidal cry1ac protein and its toxicity to nontarget aquatic organisms.the widespread cultivation of bacillus thuringiensis crops has raised public concerns on their risk to nontarget organisms. persistence of cry1ac protein in soil, sediment and water and its toxicity to nontarget aquatic organisms were determined. the dissipation of cry1ac toxin was well described using first order kinetics, with the half-lives (dt50) ranging from 0.8 to 3.2, 2.1 to 7.6 and 11.0 to 15.8 d in soil, sediment and water, respectively. microbial degradation played a key role in the di ...201324151928
expression profile and regulation of spore and parasporal crystal formation-associated genes in bacillus thuringiensis.bacillus thuringiensis, a gram-positive endospore-forming bacterium, is characterized by the formation of parasporal crystals consisting of insecticidal crystal proteins (icps) during sporulation. we reveal gene expression profiles and regulatory mechanisms associated with spore and parasporal crystal formation based on transcriptomics and proteomics data of b. thuringiensis strain ct-43. during sporulation, five icp genes encoded by ct-43 were specifically transcribed; moreover, most of the spo ...201324215520
laboratory tests on the efficacy of vbc60035, a combined larvicidal formulation of bacillus thuringiensis israelensis (strain am65-52) and bacillus sphaericus (strain 2362) against aedes albopictus in simulated catch basins.catch basins are a common breeding site for mosquito larvae in urban areas. the arrival in spain of the asian tiger mosquito, aedes albopictus, has turned catch basins into a challenging public health issue in some areas such as the baix llobregat region, where more than 135,000 units are treated per year in a large-scale application program. although biorational larvicides are used, modern formulations providing longer efficacy periods could lead to manpower savings. laboratory indoor trials ar ...201324199503
receptors and lethal effect of bacillus thuringiensis insecticidal crystal proteins to the anticarsia gemmatalis (lepidoptera, noctuidae).bioassays with insecticidal crystal proteins (icps) from bacillus thuringiensis have demonstrated that cry1aa, cry1ac, and cry1ba are the most active toxins on larvae of the anticarsia gemmatalis. the toxins cry1da and cry1ea are less toxic, and toxins cry2aa are not active. binding of these icps to midgut sections of the a. gemmatalis larvae was studied using streptavidin-mediated detection. the observed staining patterns showed that cry1aa and cry1ac bound to the brush border throughout the wh ...201324195006
potential of sugarcane bagasse (agro-industrial waste) for the production of bacillus thuringiensis israelensis.sugarcane bagasse is a renewable resource that can be used to produce biopesticide for the control of mosquito vectors. in the present study, we demonstrated that cane processed bagasse could be used to produce bacillus thuringiensis serovar israelensis (bti) for control of mosquito vectors viz: culex quinquefasciatus, anopheles stephensi and aedes aegypti. biochemical studies indicated that the bti spore/crystal toxins produced from the test culture medium (bagasse, bg + soybean, sb) are higher ...201324189680
applying an integrated refuge to manage western corn rootworm (coleoptera: chrysomelidae): effects on survival, fitness, and selection pressure.the refuge strategy can delay resistance of insect pests to transgenic maize producing toxins from bacillus thuringiensis (bt). this is important for the western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), because of its history of adaptation to several management practices. a 2-yr study across four locations was conducted to measure the effects of integrated refuge (i.e., blended refuge) on western corn rootworm survival to adulthood, fitness characteristi ...201324224265
effect of bt maize and soil insecticides on yield, injury, and rootworm survival: implications for resistance management.a 2-yr field experiment was conducted to determine the effects on diabrotica spp. (coleoptera: chrysomelidae) of an insecticidal seed treatment (poncho 1250, (ai)/clothianidin) and a granular insecticide (aztec 2.1g, (ai)/tebupirimphos and cyfluthrin) alone and in combination with maize producing the insectidical toxin cry3bb1 derived from the bacterium bacillus thuringiensis (bt). yields for bt maize plots were significantly greater than for non-bt maize; however, insecticides did not significa ...201324224233
unlinked genetic loci control the reduced transcription of aminopeptidase n 1 and 3 in the european corn borer and determine tolerance to bacillus thuringiensis cry1ab toxin.transgenic expression of bacillus thuringiensis (bt) crystalline (cry) toxins by crop plants result in reduced insect feeding damage, but sustainability is threatened by the development of resistance traits in target insect populations. we investigated bt toxin resistance trait in a laboratory colony of the european corn borer, ostrinia nubilalis, selected for increased survival when exposed to cry1ab and correlated survival on cry1ab toxin with a constitutive ∼146.2 ± 17.3-fold reduction in mid ...201324121099
dna-based screening for an intracellular cadherin mutation conferring non-recessive cry1ac resistance in field populations of helicoverpa armigera.a number of cadherin mutants conferring resistance to bt toxin cry1ac have been reported in three major lepidopteran pests, including helicoverpa armigera. unlike most of the cadherin mutants conferring recessive resistance, an allele (r15) with a 55aa deletion in the intracellular domain of cadherin (hacad) was previously identified to cause non-recessive resistance to cry1ac in h. armigera. in the present study, a dna-based pcr method was developed to screen the r15 allele from field populatio ...201325149249
effect of sub-lethal doses of bacillus thuringiensis subsp. aizawai and deltamethrin with regard to fertility and organ toxicity in pregnant albino rats.products with bacillus thuringiensis (bt) and synthetic insecticides have been widely used against important vectors of human diseases. however, few studies have addressed the application of these substances on the female reproduction apparatus during pregnancy at doses that do not cause clinical symptoms of intoxication. seventy pregnant albino rats were analyzed with regard to fertility and histopathology of the kidneys, liver and lungs as well as the morphology of the neonates. the rats were ...201322436576
[conduct of the oviposition of aedes aegypti (l.) in the presence of macrocyclops albidus (j.) and bacillus thuringiensis var. israelensis under lab conditions].the behaviour of the oviposition of pregnant females of aedes aegypti in the presence of biological agents: macrocyclops albidus (copepoda: cyclopoidea) or bacillus thuringiensis var. israelensis (bti) was evaluated under lab conditions. recipients containing 225 ml of dechlorinated water were placed for oviposition with three variants: water with copepods, water with bti, and water. the average of eggs layed in the recipients with copepods and bti were 1 227.9 and 1 200.8, respectively, a figur ...201323427425
bacillus thuringiensis insecticidal three-domain cry toxins: mode of action, insect resistance and consequences for crop protection.bacillus thuringiensis bacteria are insect pathogens that produce different cry and cyt toxins to kill their hosts. here we review the group of three-domain cry (3d-cry) toxins. expression of these 3d-cry toxins in transgenic crops has contributed to efficient control of insect pests and a reduction in the use of chemical insecticides. the mode of action of 3d-cry toxins involves sequential interactions with several insect midgut proteins that facilitate the formation of an oligomeric structure ...201322540421
isolation and molecular characterisation of alkaline protease producing bacillus thuringiensis.proteases are of particular interest because of their action on insoluble keratin substrates and generally on a broad range of protein substrates. proteases are one of the most important groups of industrial enzymes used in detergent, protein, brewing, meat, photographic, leather, dairy, pharmaceutical and food industry. in the present study, the organism isolated from the protein rich soil sample was identified by biochemical and molecular characterisation as bacillus thuringiensis and further ...201322826099
immunosuppressive properties of a protein (rvpr1) from the venom of the endoparasitic wasp, pimpla hypochondriaca: mechanism of action and potential use for improving biological control strategies.previously, it was determined that the presence of rvpr1 (a recombinant pimpla hypochondriaca venom protein), in the haemocoel of two lepidopteran larvae, significantly increases their susceptibility to the biological control agents (bcas), bacillus thuringiensis (bt) and beauveria bassiana (richards and dani, 2010; richards et al., 2011). the current work examines the mechanism of action of rvpr1 and demonstrates that it binds to the surface of some haemocytes and disrupts the organization of t ...201322698823
cyt toxins produced by bacillus thuringiensis: a protein fold conserved in several pathogenic microorganisms.bacillus thuringiensis bacteria produce different insecticidal proteins known as cry and cyt toxins. among them the cyt toxins represent a special and interesting group of proteins. cyt toxins are able to affect insect midgut cells but also are able to increase the insecticidal damage of certain cry toxins. furthermore, the cyt toxins are able to overcome resistance to cry toxins in mosquitoes. there is an increasing potential for the use of cyt toxins in insect control. however, we still need t ...201322691603
cytolytic peptide fragments of cyt1aa from bacillus thuringiensis subsp. israelensis.cyt1aa is the major and most active component of the parasporal crystal of the gram-positive soil entomopathogenic bacterium bacillus thuringiensis subsp. israelensis. the cyt1aa protoxin exhibits some hemolytic and cytolytic activity. however, highly active 22-25 kda toxins are obtained after proteolysis of cyt1aa from both the n- and the c-termini. as shown in this study, preliminary binding of the protoxin to polylamellary liposomes or partial denaturation of cyt1aa and further processing by ...201322875467
[isolation of bacillus thuringiensis imv b-7324 fibrinolytic peptidase].fibrinolytic peptidase of bacillus thuringiensis imv b-7324 was isolated by ammonium sulfate fractionation, gel-filtration and ion exchange chromatography on tsk-gels--toyopearl hw-55 and deae 650 (m). fibrinolytic activity of the purified enzyme was 87.9 u/mg of protein that was 19.9 times higher compared with the supernatant cultural liquid, the yield on its activity reached 31%. the gel-filtration on sepharose 6b and by sds-page electrophoresis demonstrated the homogeneity of the purified fib ...201323120980
a tenebrio molitor gpi-anchored alkaline phosphatase is involved in binding of bacillus thuringiensis cry3aa to brush border membrane vesicles.bacillus thuringiensis cry toxins recognizes their target cells in part by the binding to glycosyl-phosphatidyl-inositol (gpi) anchored proteins such as aminopeptidase-n (apn) or alkaline phosphatases (alp). treatment of tenebrio molitor brush border membrane vesicles (bbmv) with phospholipase c that cleaves out gpi-anchored proteins from the membranes, showed that gpi-anchored proteins are involved in binding of cry3aa toxin to bbmv. a 68 kda gpi-anchored alp was shown to bind cry3aa by toxin o ...201322743140
screening and identification of a bacillus thuringiensis strain s1/4 with large and efficient insecticidal activities.the bacterium bacillus thuringiensis was recognized for its entomopathogenic activities related to cry and cyt proteins forming the δ-endotoxins and some extracellular activities like the vegetative insecticidal proteins (vip) and cry1i. these activities may act specifically against diverse organisms and some of them typically characterize each strain. here, we screened a set of 212 b. thuringiensis strains to search the higher insecticidal activities. these strains had bipyramidal and cubic cry ...201322915162
microbial control of the cotton leafworm spodoptera littoralis (boisd.) by egyptian bacillus thuringiensis isolates.four local bacillus thuringiensis (bt) isolates that had been serologically identified as bt var. kurstaki (btk2, btk3, and btk66) and bt var. mexicanensis (btm27), in addition to two reference strains (4d20 and 4ac1), were laboratory assayed as microbial control agents against the egyptian cotton leafworm spodoptera littoralis (boisd.). polymerase chain reaction (pcr) amplification analysis revealed that each of the six experimental strains carries, at least, a cry1 type gene which expresses a ...201322983675
neurobactrus, a novel, highly effective, and environmentally friendly recombinant baculovirus insecticide.a novel recombinant baculovirus, neurobactrus, was constructed to develop an improved baculovirus insecticide with additional beneficial properties, such as a higher insecticidal activity and improved recovery, compared to wild-type baculovirus. for the construction of neurobactrus, the bacillus thuringiensis crystal protein gene (here termed cry1-5) was introduced into the autographa californica nucleopolyhedrovirus (acmnpv) genome by fusion of the polyhedrin-cry1-5-polyhedrin genes under the c ...201323064343
risk assessment of cry toxins of bacillus thuringiensis on the predatory mites euseius concordis and neoseiulus californicus (acari: phytoseiidae).genetically modified plants carrying cry toxins of bacillus thuringiensis (bt) are widely used for pest control. possible adverse effects as a result of the use of this control technique to non-target organisms is still a concern; however, few studies have addressed the effects of bt crops on phytoseiid predatory mites. phytoseiids are important for the natural control of phytophagous mites, but they can also feed on pollen, plant exudates, etc. thus, phytoseiids may ingest bt toxins through sev ...201323053912
a new gene superfamily of pathogen-response (repat) genes in lepidoptera: classification and expression analysis.repat (response to pathogens) genes were first identified in the midgut of spodoptera exigua (lepidoptera: noctuidae) in response to bacillus thuringiensis and baculovirus exposure. since then, additional repat gene homologs have been identified in different studies. in this study the comprehensive larval transcriptome from s. exigua was analyzed for the presence of novel repat-homolog sequences. these analyses revealed the presence of at least 46 repat genes in s. exigua, establishing a new gen ...201323036664
effects of cry34/35ab1 corn on the survival and development of western corn rootworm, diabrotica virgifera virgifera.the western corn rootworm, diabrotica virgifera virgifera leconte, is a major agricultural pest that is managed with transgenic corn, zea mays l., expressing genes from bacillus thuringiensis berliner (bt). the effects of bt corn producing cry34/35ab1 (event das-59122-7) and entomopathogens on the survival and development of larval d. v. virgifera were examined in laboratory, field and greenhouse experiments.201323109348
bacillus thuringiensis cry1a toxin-binding glycoconjugates present on the brush border membrane and in the peritrophic membrane of the douglas-fir tussock moth are peritrophins.bacillus thuringiensis (bt) cry1a toxin-binding sites in the douglas fir tussock moth (dftm) larval gut were localized using immunofluorescence microscopy. cry1aa, cry1ab and cry1ac all bound strongly to the dftm peritrophic membrane (pm); weaker binding of the cry1a toxins was observed along the apical brush border of the midgut epithelium. comparative analysis of the cry1a toxin-binding molecules in the pm and brush border membrane vesicles (bbmvs) showed that a similar toxin-binding complex w ...201323108174
transgenerational effects of feeding genetically modified maize to nulliparous sows and offspring on offspring growth and health.this study assessed the effect of feeding genetically modified maize expressing a truncated form of the cry1ab protein from bacillus thuringiensis (bt mon810 maize) to sows during gestation and lactation and their offspring from weaning to 115 d postweaning on offspring growth and health. after weaning at approximately 28 d of age (d 0), individually penned, mixed sex pigs (approximately 8 kg bw) from sows fed isogenic or bt maize diets were blocked by sow treatment, sex, and bw and randomly ass ...201323097397
bacillus thuringiensis metalloproteinase bmp1 functions as a nematicidal virulence factor.some bacillus thuringiensis strains have high toxicity to nematodes. nematicidal activity has been found in several families of crystal proteins, such as cry5, cry6, and cry55. the b. thuringiensis strain ybt-1518 has three cry genes that have high nematicidal activity. the whole genome sequence of this strain contains multiple potential virulence factors. to evaluate the pathogenic potential of virulence factors, we focused on a metalloproteinase called bmp1. it encompasses a consecutive n-term ...201323124228
evaluation of a commercial bacillus thuringiensis var. israelensis formulation for the control of chironomid midge larvae (diptera: chironomidae) in establishing rice crops in south-eastern australia.a commercial formulation of bacillus thuringiensis var. israelensis (b.t.i.) was evaluated for its potential to control chironomid midge larvae in newly sown rice crops in south-eastern australia. two replicated small-plot field trials were conducted using product application rates of 0.5-6 kg/ha. in trial 1 application rates between 2 and 6 kg product/ha all significantly (p<0.05) reduced populations of target chironominae/orthocladiinae by between 71% and 93% over the 19 day post-treatment mon ...201323131719
dna-based diagnostics for genetically modified cotton: decaplex pcr assay to differentiate mon531 and mon15985 bt cotton events.the adoption rate and global area under cultivation of genetically modified (gm) crops is dramatically increasing in recent past. gm cotton has occupied 25.0 million hectares (mha) comprising 15.6% of the global area under gm cultivation. bt cotton, expressing delta-endotoxins from bacillus thuringiensis (bt), is the only commercialized crop in india that is planted on an area of 10.6 mha. with the increase in development and commercialization of gm crops, it is necessary to develop appropriate ...201323143489
distribution and diversity analysis of bacillus thuringiensis cry genes in different soil types and geographical regions of india.molecular characterization of 117 bacillus thuringiensis (bt) isolates from various geographical locations was previously done by pcr amplification of cry genes. in present investigation, diversity of cry genes from different soil types and climatic environments was studied using rarefaction method. presence of cry1, cry2, cry3, 7, 8, cry4, cry5, 12, 14, 21, cry11, cry13 and cyt1 genes from bt strains isolated from various regions of india was determined by pcr amplification. a varied distributi ...201323160085
effect of wolbachia on insecticide susceptibility in lines of aedes aegypti.two stable infections of wolbachia pipientis, wmelpop and wmel, now established in aedes aegypti, are being used in a biocontrol program to suppress the transmission of dengue. any effects of wolbachia infection on insecticide resistance of mosquitoes may undermine the success of this program. bioassays of ae. aegypti were conducted to test for differences in response to insecticides between wolbachia infected (wmelpop, wmel) and uninfected lines. insecticides screened were bifenthrin, the pyret ...201323149015
increase in larval gut proteolytic activities and bti resistance in the dengue fever mosquito.the bioinsecticide bacillus thuringiensis var. israelensis (bti) is increasingly used worldwide for mosquito control. although no established resistance to bti has been described in the field so far, a resistant aedes aegypti strain (litox strain) was selected in the laboratory using field-collected leaf litter containing bti toxins. this selected strain exhibits a moderate resistance level to bti, but a high resistance level to individual cry toxins. as bti contains four different toxins, gener ...201323192850
effects of oral bt-maize (mon810) exposure on growth and health parameters in normal and sensitised atlantic salmon, salmo salar l.responses to gm maize bt-maize, mon810) expressing cry1ab protein from the soil bacterium bacillus thuringiensis (bt) in diets for both normal and immune-sensitised (with soyabean meal (sbm)-induced enteropathy) post-smolt atlantic salmon were investigated following 33 and 97 d of exposure. triplicate tanks of salmon were fed one of four diets, all containing 20% whole-kernel meal maize, either bt-maize or its near-isogenic maternal line, without or with 15% extracted sbm inclusion. the fish fed ...201323182224
eco-physiological response of two marine bivalves to acute exposition to commercial bt-based pesticide.microbial products based on the entomopathogenic bacterium bacillus thuringiensis (bt) are among the most common biopesticides used worldwide to suppress insect pests in forests, horticulture and agricultural crops. some of the effects of commercial bt have been recorded for terrestrial and freshwater non-target organisms but little research is available on marine fauna. nevertheless, due to the contiguity of agro-ecosystems and coastal habitats, marine fauna may be highly influenced by this con ...201323168358
development and validation of a confirmative lc-ms/ms method for the determination of ß-exotoxin thuringiensin in plant protection products and selected greenhouse crops.bacterial products based on bacillus thuringiensis are registered in many countries as plant protection products (ppps) and are widely used as insecticides and nematocides. however, certain b. thuringiensis strains produce harmful toxins and are therefore not allowed to be used as ppps. the serotype b. thuringiensis thuringiensis produces the beta-exotoxin thuringiensin (ßet) which is considered to be toxic for almost all forms of life including humans (who 1999). the use of a non-registered ppp ...201323208288
molecular characterization and genetic diversity of insecticidal crystal protein genes in native bacillus thuringiensis isolates.the western ghats of karnataka natural ecosystem are among the most diverse and is one of the eight hottest hotspots of biological diversity in the world, that runs along the western part of india through four states including karnataka. bacillus thuringiensis (bt) strains were isolated from soils of western ghats of karnataka and characterized by molecular and analytical methods as a result of which 28 new bt-like isolates were identified. bt strains were isolated from soil samples using sodium ...201323207696
bacillus thuringiensis isolates from great nicobar islands.bacillus thuringiensis (bt) strains were isolated from soil samples of great nicobar islands, one of the "hottest biodiversity hotspots," where no collection has been characterized previously. the 36 new bt isolates were obtained from 153 samples analyzed by crystal protein production with light/phase-contrast microscopy, determination of cry gene profile by sds-page, evaluation of toxicity against coleopteran, and lepidopteran insect pests, finally cloning and sequencing. majority of the isolat ...201323377491
overexpression of polyphosphate kinase gene (ppk) increases bioinsecticide production by bacillus thuringiensis.polyphosphate (polyp), synthesized by polyp kinase (ppk) using the terminal phosphate of atp as substrate, performs important functions in every living cell. the present work reports on the relationship between polyp metabolism and bioinsecticide production in bacillus thuringiensis subsp. israelensis (bti). the ppk gene of bti was cloned into vector pht315 and the effect of its overexpression on endotoxin production was determined. endotoxin production by the recombinant strain was found to be ...201323369305
agcad2 cadherin in anopheles gambiae larvae is a putative receptor of cry11ba toxin of bacillus thuringiensis subsp. jegathesan.in an effort to study the mode of action of cry11ba, we identified toxin binding proteins in anopheles gambiae larval midgut and investigated their receptor roles. previously, an aminopeptidase (agapn2) and an alkaline phosphatase (agalp1) were identified as receptors for cry11ba toxin in a. gambiae. however, an a. gambiae cadherin (agcad1) that bound cry11ba with low affinity (k(d) = 766 nm) did not support a receptor role of agcad1 for cry11ba. here, we studied a second a. gambiae cadherin (ag ...201323231770
cloning, characterization, and expression of a new cry1ab gene from dor bt-1, an indigenous isolate of bacillus thuringiensis.a new cry1ab gene was cloned from the promising local isolate, dor bt-1, a bacillus thuringiensis strain isolated from castor semilooper (achaea janata l.) cadavers from castor bean (ricinus communis l.) field. the nucleotide sequence of the cloned cry1ab gene indicated that the open reading frame consisted of 3,465 bases encoding a protein of 1,155 amino acid residues with an estimated molecular weight of 130 kda. homology comparisons revealed that the deduced amino acid sequence of cry1ab had ...201323224937
bacillus thuringiensis cry1ia10 and vip3aa protein interactions and their toxicity in spodoptera spp. (lepidoptera).the polyphagous pests belonging to the genus spodoptera are considered to be among the most important causes of damage and are widely distributed throughout the americas'. due to the extensive use of genetically modified plants containing bacillus thuringiensis genes that code for insecticidal proteins, resistant insects may arise. to prevent the development of resistance, pyramided plants, which express multiple insecticidal proteins that act through distinct mode of actions, can be used. this ...201323220241
histopathological effects and determination of the putative receptor of bacillus thuringiensis cry1da toxin in spodoptera littoralis midgut.bacillus thuringiensis subsp. aizawai strain hd133, known by its effectiveness against spodoptera species, produces many insecticidal proteins including cry1ab, cry1ca and cry1da. in the present study, the insecticidal activity of cry1da against spodoptera littoralis was investigated. it showed toxicity with an lc(50) of 224.4 ng/cm(2) with 95% confidence limits of (178.61-270.19) and an lc(90) of 467.77 ng/cm(2) with 95% confidence limits of (392.89-542.65). the midgut histopathology of cry1da ...201323220238
ochratoxin a management in vineyards by lobesia botrana biocontrol.grape berries attacked by lobesia botrana larvae are more easily infected by aspergillus section nigri (black aspergilli) ochratoxigenic species. two-year field trials were carried out in apulia (italy) to evaluate a bioinsecticide control strategy against l. botrana and the indirect effect on reducing ochratoxin a (ota) contamination in vineyards. a commercial bacillus thuringiensis formulate and an experimental beauveria bassiana (item-1559) formulate were tested in two vineyards cultivated wi ...201323282670
affinity maturation of cry1aa toxin to the bombyx mori cadherin-like receptor by directed evolution.improvement of the activity and insecticidal spectrum of cloned cry toxins of bacillus thuringiensis should allow for their wider application as biopesticides and a gene source for gene-modified crops. the insecticidal activity of cry toxins depends on their binding to the receptor. therefore, as a model, we aimed to generate improved binding affinity mutant toxins against bombyx mori cadherin-like receptor (btr175) using methods of directed evolution with the expectation of insecticidal activit ...201323247992
parasporin 1ac2, a novel cytotoxic crystal protein isolated from bacillus thuringiensis b0462 strain.two novel parasporin (ps) genes were cloned from bacillus thuringiensis b0462 strain. one was 100 % identical even in nucleotide sequence level with that of parasporin-1aa (ps1aa1) from b. thuringiensis a1190 strain. the other (ps1ac2) showed significant homology (99 % identity) to that of ps1ac1 from b. thuringiensis 87-29 strain. the 15 kda (s(113)-r(250)) and 60 kda (i(251)-s(777)) fragments consisting of an active form of ps1ac2 were expressed as his-tag fusion. upon purification under denat ...201323306354
sex differences in host defence interfere with parasite-mediated selection for outcrossing during host-parasite coevolution.the red queen hypothesis proposes that coevolving parasites select for outcrossing in the host. outcrossing relies on males, which often show lower immune investment due to, for example, sexual selection. here, we demonstrate that such sex differences in immunity interfere with parasite-mediated selection for outcrossing. two independent coevolution experiments with caenorhabditis elegans and its microparasite bacillus thuringiensis produced decreased yet stable frequencies of outcrossing male h ...201323301667
impact of six transgenic bacillus thuringiensis rice lines on four nontarget thrips species attacking rice panicles in the paddy field.as a key component of ecological risk assessments, nontarget effects of bacillus thuringiensis (bt) rice have been tested under laboratory and field conditions for various organisms. a 2-yr field experiment was conducted to observe the nontarget effects of six transgenic rice lines (expressing the cry1ab or fused protein of cry1ab and cry1ac) on four nontarget thrips species including frankliniella intonsa (trybom), f. tenuicornis (uzel), haplothrips aculeatus (f.), and h. tritici (kurd), as com ...201323339799
application of box-behnken experimental design to optimize the extraction of insecticidal cry1ac from soil.a validated method for analyzing cry proteins is a premise to study the fate and ecological effects of contaminants associated with genetically engineered bacillus thuringiensis crops. the current study has optimized the extraction method to analyze cry1ac protein in soil using a response surface methodology with a three-level-three-factor box-behnken experimental design (bbd). the optimum extraction conditions were at 21 °c and 630 rpm for 2 h. regression analysis showed a good fit of the exper ...201323327690
laboratory assessment of the impacts of transgenic bt rice on the ecological fitness of the soil non-target arthropod, folsomia candida (collembola: isotomidae).transgenic rice expressing bacillus thuringiensis (bt) endotoxins (bt rice) for pest control is considered an important solution to food security in china. however, tests for potential effects on non-target soil organisms are required for environmental risk assessment. the soil collembolan folsomia candida l. (collembola: isotomidae) is a potential non-target arthropod that is often used as a biological indicator in bio-safety assessments of transgenic crops. in the present study, the roots, ste ...201323322316
electrogenerated chemiluminescence immunosensor for bacillus thuringiensis cry1ac based on fe3o4@au nanoparticles.a highly sensitive electrochemiluminescence (ecl) immunosensor for cry1ac was fabricated. the primary antibody anti-cry1ac was immobilized onto core-shell structural fe(3)o(4)@au nanoparticles. the antigen and glucose-oxidase-labeled secondary antibody were then successively combined to form sandwich-type immunocomplexes through a specific interaction. the magnetic particles loaded with sandwich immune complexes were attracted to a magnet-controlled glass carbon electrode (gce) by an external ma ...201323317307
cyt1aa from bacillus thuringiensis subsp. israelensis enhances mosquitocidal activity of b. thuringiensis subsp. kurstaki hd-1 against aedes aegypti but not culex quinquefasciatus.the cyt1aa protein of bacillus thuringiensis subsp. israelensis is known to synergize mosquitocidal proteins of b. thuringiensis and bacillus sphaericus strains. cyt1aa is highly lipophilic, and after binding in vivo to the midgut microvillar membrane serves as a "receptor" for mosquitocidal cry proteins, which subsequently form cation channels that kill mosquito larvae. here we report that cyt1aa can serve a similar function for lepidopteran-specific cry proteins of b. thuringiensis in certain ...201323314373
influence of oxalic and malic acids in chickpea leaf exudates on the biological activity of cryiac towards helicoverpa armigera.efforts are being made to express toxin genes from the bacterium, bacillus thuringiensis (bt) in chickpea for minimizing the losses due to the pod borer, helicoverpa armigera. however, there is an apprehension that acidic exudates in chickpea leaves may influence the protoxin-toxin conversion in the insect midgut, and thus, reduce the efficacy of bt toxins. therefore, we studied the influence of organic acids (oxalic acid and malic acid) present in the trichome exudates of chickpea on the biolog ...201323391855
long-term survival of bacillus thuringiensis subsp. kurstaki in a field trial.long-term survival of bacillus thuringiensis subsp. kurstaki dmu67r has been investigated in a field trial. an experimental cabbage plot was sprayed with dmu67r in 1993 and was allowed to lie fallow since then. the investigation reported here was carried out from 2001 to 2007 in a single square meter within the plot using a systematic randomized sampling approach. the bacterium survived at relative low densities in these 13 years after spraying. statistical analyses revealed that the overall den ...201323391227
effect of vegetation on the presence and genetic diversity of bacillus thuringiensis in soil.bacillus thuringiensis isolates were obtained from soil samples collected at different sites located in the same region but with different vegetation. the sites showed different frequencies of b. thuringiensis, depending on the type of vegetation. strains of b. thuringiensis were found to be less common in samples of riparian forest soil than in soil of other types of vegetation. the rate of occurrence of b. thuringiensis in the samples also varied according to the vegetation. these results show ...201323391226
a phenylalanine clamp controls substrate specificity in the quorum-quenching metallo-γ-lactonase from bacillus thuringiensis.autoinducer inactivator a (aiia) is a metal-dependent n-acyl homoserine lactone hydrolase that displays broad substrate specificity but shows a preference for substrates with long n-acyl substitutions. previously, crystal structures of aiia in complex with the ring-opened product n-hexanoyl-l-homoserine revealed binding interactions near the metal center but did not identify a binding pocket for the n-acyl chains of longer substrates. here we report the crystal structure of an aiia mutant, f107w ...201323387521
alteration in bacillus thuringiensis toxicity by curing gut flora: novel approach for mosquito resistance management.mosquitoes are known for acquiring resistance against insecticides in many ways, namely target side mutation, enzyme modification, sequestration, quick elimination, etc. but, the role of microflora present in abundance in the larval midgut is less explored with respect to their role in insecticide resistance. during the course of their development, mosquitoes are continuously exposed to microbes and have naturally acquired midgut microbial flora. this midgut flora can modulate the mosquito's sus ...201323820604
purification and characterization of bacillus thuringiensis vegetative insecticidal toxin protein(s).bacillus thuringiensis subsp. aegypti c18 is an egyptian isolate, obtained from dead pink bollworm larvae. insecticidal active proteins against different insect were purified from btac18 strain during vegetative states. both the bacterial pellet and cell-free supernatant obtained during vegetative growth had insecticidal activity against black cutworm (bcw). bioassays revealed that the pellet after 48 h of growth is more potent and toxic against bcw. the toxin in the pellet was active at very hi ...201323815791
identification of a second cytotoxic protein produced by bacillus thuringiensis a1470.bacillus thuringiensis a1470 produces multiple proteins with similar molecular masses (~30 kda) with cytotoxicity against human cell lines. one that was previously identified, parasporin-4, is a β-pore-forming toxin. the n-terminal sequence of a second cytotoxic protein was identical to a partial sequence of parasporin-2 produced by b. thuringiensis a1547. pcr was performed on total plasmid dna from a1470 by using primers for parasporin-2 to amplify a gene which was then cloned. the cloned gene ...201323801126
heterologous expression and biochemical characterisation of fourteen esterases from helicoverpa armigera.esterases have recurrently been implicated in insecticide resistance in helicoverpa armigera but little is known about the underlying molecular mechanisms. we used a baculovirus system to express 14 of 30 full-length esterase genes so far identified from midgut cdna libraries of this species. all 14 produced esterase isozymes after native page and the isozymes for seven of them migrated to two regions of the gel previously associated with both organophosphate and pyrethroid resistance in various ...201323799064
enterotoxigenic profiling of emetic toxin- and enterotoxin-producing bacillus cereus, isolated from food, environmental, and clinical samples by multiplex pcr.bacillus cereus comprises the largest group of endospore-forming bacteria and can cause emetic and diarrheal food poisoning. a total of 496 b. cereus strains isolated from various sources (food, environmental, clinical) were assessed by a multiplex pcr for the presence of enterotoxin genes. the detection rate of nhea, entfm, hblc, and cytk enterotoxin genes among all b. cereus strains was 92.33%, 77.21%, 59.47%, and 47.58%, respectively. enterotoxigenic profiles were determined in emetic toxin- ...201425311736
influence of lysogeny of tectiviruses gil01 and gil16 on bacillus thuringiensis growth, biofilm formation, and swarming motility.bacillus thuringiensis is an entomopathogenic bacterium that has been used as an efficient biopesticide worldwide. despite the fact that this bacterium is usually described as an insect pathogen, its life cycle in the environment is still largely unknown. b. thuringiensis belongs to the bacillus cereus group of bacteria, which has been associated with many mobile genetic elements, such as species-specific temperate or virulent bacteriophages (phages). temperate (lysogenic) phages are able to est ...201425261525
high-quality draft genome sequence of nematocidal bacillus thuringiensis sbt003.bacillus thuringiensis represents one of the six species of "bacillus cereus group" in the genus bacillus within the family bacillaceae. strain sbt003 was isolated from soil and identified as b. thuringiensis. it harbors at least seven plasmids and produces three shapes of parasporal crystals including oval, bipyramidal and rice. sds-page analysis of spore-crystal suspension of this strain reveals six major protein bands, which implies the presence of multiple parasporal crystal genes. bioassay ...201425197449
modular genetic architecture of the toxigenic plasmid pis56-63 harboring cry1ab21 in bacillus thuringiensis subsp. thuringiensis strain is5056.bacillus thuringiensis subsp. thuringiensis is5056, a strain highly toxic to trichoplusia ni larvae, produces the newly described cry1ab21 delta-endotoxin encoded by a gene located in the 63.8 kb pis56-63 plasmid. in this report we present the structure and functional similarity of this plasmid to other b. thuringiensis large toxigenic plasmids with particular interest focused on its modular architecture. the 61 open reading frames (orfs) of the plasmid made four functional modules: (i) m1-mic, ...201425115108
quorum sensing in bacillus thuringiensis is required for completion of a full infectious cycle in the insect.bacterial cell-cell communication or quorum sensing (qs) is a biological process commonly described as allowing bacteria belonging to a same pherotype to coordinate gene expression to cell density. in gram-positive bacteria, cell-cell communication mainly relies on cytoplasmic sensors regulated by secreted and re-imported signaling peptides. the bacillus quorum sensors rap, nprr, and plcr were previously identified as the first members of a new protein family called rnpp. except for the rap prot ...201425089349
regulation of cry gene expression in bacillus thuringiensis.bacillus thuringiensis differs from the closely related bacillus cereus group species by its ability to produce crystalline inclusions. the production of these crystals mainly results from the expression of the cry genes, from the stability of their transcripts and from the synthesis, accumulation and crystallization of large amounts of insecticidal cry proteins. this process normally coincides with sporulation and is regulated by various factors operating at the transcriptional, post-transcript ...201425055802
behavior of transition state regulator abrb in batch cultures of bacillus thuringiensis.the transition state regulator abrb is involved in the regulation of various cellular functions such as exponential growth, transition state and sporulation onset, due to its ability to activate, suppress or prevent the inappropriate expression of various genes in bacillus subtilis. in order to understand combined behavior in batch cultures of abrb in bacillus thuringiensis, we cloned and expressed the abrb gene of b. thuringiensis in escherichia coli. the deduced sequence of abrb gene coded for ...201425002359
crystalliferous bacillus cereus group bacteria from a maryland hardwood forest are dominated by psychrotolerant strains.crystal-forming bacteria of the bacillus cereus group were isolated from soil samples collected at different elevations within a mixed hardwood forest in central maryland, and their phylogenetic relationships determined by multilocus sequence analysis. the vast majority of isolates obtained were associated with two phylogenetic groups known to be psychrotolerant, with very few isolates representing phylogenetic groups more typically associated with bacillus thuringiensis. isolates from the psych ...201424985699
bacillus cereus and bacillus thuringiensis spores in korean rice: prevalence and toxin production as affected by production area and degree of milling.we determined the prevalence of and toxin production by bacillus cereus and bacillus thuringiensis in korean rice as affected by production area and degree of milling. rough rice was collected from 64 farms in 22 agricultural areas and polished to produce brown and white rice. in total, rice samples were broadly contaminated with b. cereus spores, with no effect of production area. the prevalence and counts of b. cereus spores declined as milling progressed. frequencies of hemolysin bl (hbl) pro ...201424929722
comparative analysis of quantitative reverse transcription real-time pcr and commercial enzyme imunoassays for detection of enterotoxigenic bacillus thuringiensis isolates.entomopathogenic bacillus thuringiensis is closely related to bacillus cereus, a human pathogen known to cause emesis and diarrhea. standard detection methods do not distinguish these bacilli. hemolysin bl (hbl) and non-hemolytic enterotoxin (nhe) genes that encode, respectively, hbl and nhe enterotoxins, are known to be harbored in both bacterial species, suggesting that differentiation of these bacilli is clinically and epidemiologically relevant. in this study the reliability of quantitative ...201424913432
bactericidal thurincin h causes unique morphological changes in bacillus cereus f4552 without affecting membrane permeability.thurincin h is an antilisterial bacteriocin produced by bacillus thuringiensis sf361. it exhibits inhibitory activity against a wide range of gram-positive foodborne pathogens and spoilage bacteria including listeria monocytogenes, b. cereus, and b. subtilis. this hydrophobic, anionic bacteriocin folds into a hairpin structure maintained by four pairs of unique sulfur to α-carbon thioether bonds. as its hydrophobicity and structure are quite different from most archived bacteriocins, this study ...201424891232
large-scale purification, characterization, and spore outgrowth inhibitory effect of thurincin h, a bacteriocin produced by bacillus thuringiensis sf361.large-scale purification of the highly hydrophobic bacteriocin thurincin h was accomplished via a novel and simple two-step method: ammonia sulfate precipitation and c18 solid-phase extraction. the inhibition spectrum and stability of thurincin h as well as its antagonistic activity against bacillus cereus f4552 spores were further characterized. in the purification method, secreted proteins contained in the supernatant of a 40 h incubated culture of b. thuringiensis sf361 were precipitated by 6 ...201424798125
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