Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| identification of the bacillus anthracis (gamma) phage receptor. | bacillus anthracis, a gram-positive, spore-forming bacterium, is the etiological agent of anthrax. it belongs to the bacillus cereus group, which also contains bacillus cereus and bacillus thuringiensis. most b. anthracis strains are sensitive to phage gamma, but most b. cereus and b. thuringiensis strains are resistant to the lytic action of phage gamma. here, we report the identification of a protein involved in the bacterial receptor for the gamma phage, which we term gamr (gamma phage recept ... | 2005 | 16166537 |
| a comparative study of bacillus cereus, bacillus thuringiensis and bacillus anthracis extracellular proteomes. | bacillus cereus, bacillus thuringiensis and bacillus anthracis are closely related species that share a similar genetic background but occupy different ecological niches. virulence plasmids bearing genes coding for toxins, may explain, at least partly, this specialization. we have compared by 2-de in the early stationary phase of growth the extracellular proteomes of three strains of these species that have lost their virulence plasmids. proteins expected to be secreted or to belong to the cell ... | 2005 | 16167365 |
| characterization of a new bacillus thuringiensis endotoxin, cry47aa, from strains that are toxic to the australian sheep blowfly, lucilia cuprina. | sixteen isolates of bacillus thuringiensis, derived from various soil samples collected in australia, are highly toxic to larvae of the sheep blowfly (lucilia cuprina). the toxin gene from one of the strains (caa890) was cloned by genome walking, and sequencing of the cloned fragments revealed a new cry gene, encoding a protein of 1134 amino acid residues, with a theoretical molecular mass of 139,209da. based on the amino acid sequence comparison with known cry delta-endotoxins, the gene was des ... | 2005 | 16168574 |
| co-expression of bacillus thuringiensis cry4ba and cyt2aa2 in escherichia coli revealed high synergism against aedes aegypti and culex quinquefasciatus larvae. | cry4ba is a delta-endotoxin produced by bacillus thuringiensis subsp. israelensis and cyt2aa2 is a cytolytic delta-endotoxin produced by b. thuringiensis subsp. darmstadiensis. cry4ba produced in escherichia coli was toxic to aedes aegypti larvae (lc(50)=140 ng ml(-1)) but virtually inactive to culex quinquefasciatus larvae. cyt2aa2 expressed in e. coli exhibited moderate activity against a. aegypti and c. quinquefasciatus larvae with lc(50) values of 350 and 250 ng ml(-1), respectively. co-expr ... | 2005 | 16168580 |
| piezoelectric-excited millimeter-sized cantilever (pemc) sensors detect bacillus anthracis at 300 spores/ml. | piezoelectric-excited millimeter-sized cantilever (pemc) sensors consisting of a piezoelectric and a borosilicate glass layer with a sensing area of 2.48 mm2 were fabricated. antibody specific to bacillus anthracis (ba, sterne strain 7702) spores was immobilized on pemc sensors, and exposed to spores (300 to 3x10(6) spores/ml). the resonant frequency decreased at a rate proportional to the spore concentration and reached a steady state frequency change of 5+/-5 hz (n=3), 92+/-7 hz (n=3), 500+/-1 ... | 2006 | 16169715 |
| insertion behavior of the bacillus thuringiensis cry4ba insecticidal protein into lipid monolayers. | toxicity mechanisms of bacillus thuringiensis cry insecticidal proteins involve membrane insertion and lytic pore formation in lipid bilayers of the target larval midgut cell membranes. the b. thuringiensis cry4ba mosquito-larvicidal protein has been shown to be capable of permeabilizing liposome vesicles and of forming ion channels in planar lipid bilayers. here, the membrane interaction of the 65-kda activated cry4ba protein with the lipid monolayers, comprising dipalmitoyl phosphatidylcholine ... | 2005 | 16171774 |
| development of transgenic sorghum for insect resistance against the spotted stem borer (chilo partellus). | transgenic sorghum plants expressing a synthetic cry1ac gene from bacillus thuringiensis (bt) under the control of a wound-inducible promoter from the maize protease inhibitor gene (mpic1) were produced via particle bombardment of shoot apices. plants were regenerated from the transformed shoot apices via direct somatic embryogenesis with an intermittent three-step selection strategy using the herbicide basta. molecular characterisation based on polymerase chain reaction and southern blot analys ... | 2005 | 16172896 |
| effect of biological additives and micronutrients on the anaerobic digestion of physicochemical sludge. | two additives (lyophilized bacilli and enzymes) and a solution of micronutrients (fe, co, ni and mo) were tried separately and in combination, in order to assess their effect on the anaerobic digestion of waste sludge from an enhanced primary treatment (ept) of municipal wastewater. three batch tests were carried out in serological bottles. in the first test, addition of bacilli increased production of methane from day 11 and at day 1 7 the production was 95% greater than the control. in that ex ... | 2005 | 16180439 |
| a bacillus thuringiensis isolation method utilizing a novel stain, low selection and high throughput produced atypical results. | bacillus thuringiensis is a bacterium known for producing protein crystals with insecticidal properties. these toxins are widely sought after for controlling agricultural pests due to both their specificity and their applicability in transgenic plants. there is great interest in isolating strains with improved or novel toxin characteristics, however isolating b. thuringiensis from the environment is time consuming and yields relatively few isolates of interest. new approaches to b. thuringiensis ... | 2005 | 16181492 |
| will transgenic plants adversely affect the environment? | transgenic insecticidal plants based on bacillus thuringiensis (bt) endotoxins, on proteinase inhibitors and on lectins, and transgenic herbicide tolerant plants are widely used in modern agriculture. the results of the studies on likelihood and non-likelihood of adverse effects of transgenic plants on the environment including: (i) effects on nontarget species; (ii) invasiveness; (iii) potential for transgenes to 'escape' into the environment by horizontal gene transfer; and (iv) adverse effect ... | 2005 | 16184014 |
| transgenic indica rice plants harboring a synthetic cry2a* gene of bacillus thuringiensis exhibit enhanced resistance against lepidopteran rice pests. | a novel synthetic cry2a* gene was introduced into the elite indica rice restorer line minghui 63 by agrobacterium-mediated transformation. a total of 102 independent transformants were obtained. among them, 71 transformants were positive cry2a* plants according to pcr analysis. four highly insect-resistant lines with single-copy insertion (designated as 2a-1, 2a-2, 2a-3, and 2a-4) were selected based on field assessment and southern blot analysis in the t(1) generation. all four transgenic lines ... | 2005 | 16187120 |
| novel vip3-related protein from bacillus thuringiensis. | a novel vip3-related gene was identified in bacillus thuringiensis. this novel gene is 2,406 bp long and codes for a 91-kda protein (801 amino acids). this novel protein exhibits between 61 and 62% similarity with vip3a proteins and is designated vip3ba1. vip3ba1 has several specific features. differences between vip3ba1 and the vip3a proteins are spread throughout the sequence but are more frequent in the c-terminal part from amino acid 456 onward. the regions containing the two proteolytic pro ... | 2005 | 16204549 |
| effects of bacillus thuringiensis kurstaki on malpighian tubule cells of thaumetopoea pityocampa (lepidoptera: thaumetopoeidae) larvae. | in this study effects of bacillus thuringiensis kurstaki (btk) on malpighian tubule cells of thaumetopoea pityocampa (lepidoptera: thaumetopoeidae) larvae was investigated by electron microscopy. 3 mg/l btk was given with food. after btk administration, the malpighian tubule cells were investigated and compared with a control group. 3 and 6 hrs after btk administration swelling in malpighian tubule cells was observed. swelling of mitochondria and separation of their cristae was seen after 12 hrs ... | 2005 | 16212102 |
| molecular dynamics simulations of the cytolytic toxin cyt1a in solution. | cytolytic toxin cyt1a from bacillus thuringiensis var. israelensis is used as an environmentally friendly insecticide, but its mode of action has not been clearly established. one main obstacle seems to be the lack of the experimentally determined structure of the toxin. as a first step in computer simulations of cyt1a, in this paper, a three-dimensional molecular structure of cyt1a in solution was generated by homology modeling, potential energy minimization and molecular dynamics. regions of t ... | 2005 | 16220687 |
| additional morphological and physiological heterogeneity within the midgut of larval aedes aegypti (diptera: culicidae) revealed by histology, electrophysiology, and effects of bacillus thuringiensis endotoxin. | analysis of larval aedes aegypti midgut using scanning electron microscopy, nuclear and mitochondrial dyes, response to bacillus thuringiensis israelensis cryivb toxin, and electrophysiology is described. the anterior ventriculus ("stomach") region is found to have much lower mitochondrial densities than other midgut regions. the transitional region is distinguished by apical surface architecture, and by region-specific effects of cryivb endotoxin. in this region cryivb causes holes ranging from ... | 2005 | 16221479 |
| delayed resistance to transgenic cotton in pink bollworm. | transgenic crops producing bacillus thuringiensis (bt) toxins kill some key insect pests and thus can reduce reliance on insecticides. widespread planting of such bt crops increased concerns that their usefulness would be cut short by rapid evolution of resistance to bt toxins by pests. pink bollworm (pectinophora gossypiella) is a major pest that has experienced intense selection for resistance to bt cotton in arizona since 1997. we monitored pink bollworm resistance to bt toxin for 8 years wit ... | 2005 | 16227430 |
| a novel industrial-level reactor with two dynamic changes of air for solid-state fermentation. | a novel industrial-level solid-state reactor (70 m3) with two dynamic changes of air was designed and has been put into operation successfully, in which the unite of virulence of bacillus thuringiensis produced is maintained above 18,000 iu/mg. two dynamic changes of air (including air pressure pulsation and internal circulation) in the fermentor can increase mass and heat transfers, as well as improve the porosity within the substrate. the reactor is novel and of significance in exploiting nume ... | 2002 | 16233189 |
| identification of novel indigenous bacillus thuringiensis isolates. | internally transcribed spacers (its) characterization and distribution of repetitive extragenic palindromic (rep) sequences were studied in the genome of 223 field isolates of bacillus thuringiensis from madurai, india. they were characterized by morphological, biochemical and molecular methods. one hundred and twenty four of a total 223 isolates fitted its characterization of b. thuringiensis varieties known. significant genomic variation was observed among seven isolates using rep primers. the ... | 2005 | 16235719 |
| effect of temperature and relative humidity on the cellular defense response of ephestia kuehniella larvae fed bacillus thuringiensis. | while maintained under all combinations of three temperatures and two rh, fifth instar larvae of the mediterranean flour moth, ephestia kuehniella were fed wheat treated with spores and crystals of bacillus thuringiensis var. kurstaki. larvae that had fed on wheat with the bacterial preparation contained higher concentrations of nodules in their haemocoel than did larvae fed on wheat without bacteria. nodule concentrations in larvae fed untreated wheat were unaffected by temperature or relative ... | 2005 | 16236308 |
| the autolytic phenotype of the bacillus cereus group. | to determine the autolytic phenotype of five species in the bacillus cereus group. | 2005 | 16238737 |
| bioconversion of industrial wastewater and wastewater sludge into bacillus thuringiensis based biopesticides in pilot fermentor. | starch industry wastewater (sww), slaughterhouse wastewater (shww) and secondary sludges from three different wastewater treatment plants (jonquière--jqs, communauté urbaine de québec--cuqs and black lake-bls) were used as raw materials for the production of bacillus thuringiensis (bt) based biopesticides in a pilot scale fermentor (100 l working volume). the slaughterhouse wastewater exhibited the lowest bt growth and entomotoxcity (tx) potential (measured against spruce budworm) due to low ava ... | 2006 | 16242319 |
| overexpression of the pepper transcription factor capf1 in transgenic virginia pine (pinus virginiana mill.) confers multiple stress tolerance and enhances organ growth. | transcription factors play an important role in regulating gene expression in response to stress and pathogen tolerance. we describe here that overexpression of an erf/ap2 pepper transcription factor (capf1) in transgenic virginia pine (pinus virginiana mill.) confers tolerance to heavy metals cadmium, copper, and zinc, to heat, and to pathogens bacillus thuringiensis and staphylococcus epidermidis, as by the survival rate of transgenic plants and the number of decreasing pathogen cells in trans ... | 2005 | 16244910 |
| assessing the transfer of genetically modified dna from feed to animal tissues. | in europe, public and scientific concerns about the environmental and food safety of gm (genetically modified) crops overshadow the potential benefits offered by crop biotechnology to improve food quality. one of the concerns regarding the use of gm food in human and animal nutrition is the effect that newly introduced sequences may have on the organism. in this paper, we assess the potential transfer of diet-derived dna to animal tissues after consumption of gm plants. blood, spleen, liver, kid ... | 2005 | 16245168 |
| gene cloning and expression of cadherin in midgut of helicoverpa armigera and its cry1a binding region. | cadherins belong to one of the families of animal glycoproteins responsible for calcium-dependent cell-cell adhesion. recent literatures showed that the cadherin-like in midgut of several insects served as the receptor of bt toxin cry1a and the variation of cadherin-like is related to insect's resistance to cry1a. the full-length cdna encoding cadherin-like of helicoverpa armigera is cloned by degenerate pcr and race techniques and the gene was designated as btr-harm, which is 5581 bp in full-le ... | 2005 | 16248428 |
| purification and characterization of cry1ac toxin binding proteins from the brush border membrane of helicoverpa armigera midgut. | several cry1ac binding proteins from midgut of helicoverpa armigera were purified using toxin-affinity chromatography. enzyme assays showed that the purified proteins had strong aminopeptidase activity. the n-terminal sequences confidently identified a 124-kda binding protein as an aminopeptidase n (apn), and some similarity suggests that a 162-kda binding protein may also be an apn. two minor binding proteins were not characterized. | 2005 | 16252132 |
| expression of the bacillus thuringiensis mosquitocidal toxin cry11aa in the aquatic bacterium asticcacaulis excentricus. | a mosquitocidal aquatic bacterium has been developed by introducing an operon containing the cry11aa, and p20 genes from bacillus thuringiensis subsp. israelensis (bti) into the gram-negative aquatic bacterium asticcacaulis excentricus. after transformation, the cry11aa gene was successfully expressed in recombinant a. excentricus under the tac promoter, at the level of 0.04 pg/cell. the recombinant bacteria were toxic to aedes aegypti larvae with an lc(50) of 6.83 x 10(5) cells/ml. we believe t ... | 2005 | 16252134 |
| insecticide resistance in culex pipiens from new york. | insecticides are the primary means to control culex pipiens, an enzootic vector of west nile virus, in the usa. to better understand how the evolution of resistance might impact control of this insect, we investigated the levels of resistance in populations collected from 2 metropolitan areas (albany and syracuse, ny) to 4 larvicides (methoprene, phenothrin, bacillus sphaericus [bs], and bacillus thuringiensis israelensis [bti]) and 1 adulticide (phenothrin) registered for mosquito control in ne ... | 2005 | 16252522 |
| a gpi-anchored alkaline phosphatase is a functional midgut receptor of cry11aa toxin in aedes aegypti larvae. | a 65 kda gpi (glycosylphosphatidyl-inositol)-anchored alp (alkaline phosphatase) was characterized as a functional receptor of the bacillus thuringiensis subsp. israelensis cry11aa toxin in aedes aegypti midgut cells. two (a 100 kda and a 65 kda) gpi-anchored proteins that bound cry11aa toxin were preferentially extracted after treatment of bbmv (brush boder membrane vesicles) from ae. aegypti midgut epithelia with phospholipase c. the 65 kda protein was further purified by toxin affinity chroma ... | 2006 | 16255715 |
| [effects of bt toxin cry1ac on biochemical responses of eisenia fetida in an artificial soil]. | bt toxin cry1ac could be introduced into soil by pollen, root exudates, and plant residues. to investigate its toxic effects, the bt toxin was added into an earthworm-cultured artificial soil, and the survival, growth rate, sperm count, protein content, and activities of acetylcholinesterase (ache), catalase (cat), glutathione s-transferase (gst) and cellulase in eisenia fetida were determined. the results suggested that bt toxin cry1ac had little effects on the biomass and physiological charact ... | 2005 | 16262071 |
| comparison of minisatellite polymorphisms in the bacillus cereus complex: a simple assay for large-scale screening and identification of strains most closely related to bacillus anthracis. | polymorphism of five tandem repeats that are monomorphic in bacillus anthracis was investigated in 230 isolates of the b. cereus group and in 5 sequenced b. cereus genomes in search for markers allowing identification of b. cereus and b. thuringiensis strains most closely related to b. anthracis. using this multiple-locus variable number of tandem repeat analysis (mlva), a cluster of 30 strains was selected for further characterization. eventually, six of these were characterized by multilocus s ... | 2005 | 16269689 |
| impact of bt corn on rhizospheric and soil eubacterial communities and on beneficial mycorrhizal symbiosis in experimental microcosms. | a polyphasic approach has been developed to gain knowledge of suitable key indicators for the evaluation of environmental impact of genetically modified bt 11 and bt 176 corn lines on soil ecosystems. we assessed the effects of bt corn (which constitutively expresses the insecticidal toxin from bacillus thuringiensis, encoded by the truncated cry1ab gene) and non-bt corn plants and their residues on rhizospheric and bulk soil eubacterial communities by means of denaturing gradient gel electropho ... | 2005 | 16269702 |
| common, but complex, mode of resistance of plutella xylostella to bacillus thuringiensis toxins cry1ab and cry1ac. | a field collected population of plutella xylostella (serd4) was selected in the laboratory with bacillus thuringiensis endotoxins cry1ac (cry1ac-sel) and cry1ab (cry1ab-sel). both subpopulations showed similar phenotypes: high resistance to the cry1a toxins and little cross-resistance to cry1ca or cry1d. a previous analysis of the cry1ac-sel showed incompletely dominant resistance to cry1ac with more than one factor, at least one of which was sex influenced. in the present study reciprocal mass ... | 2005 | 16269720 |
| monsanto's bollgard potentially compromised in india. | 2005 | 16273045 | |
| [interaction between insecticidal crystal proteins and dna molecule from bacillus thuringiensis]. | 2003 | 16276883 | |
| [cloning and expression of icp cry1ab16 gene of bacillus thuringiensis]. | with two pairs of primers designed on the basis of the sequence of cry1 and cry1ab gene from bacillus thuringiensis (bt), a novel insecticidal crystal protein crylab gene of bt was amplified from bacillus strain ac-11 by using long template pcr system. southernblot further confirmed that the novel gene existed in plasmid of the strain. the amplified fragment was sequenced and compared with cry1ab1 gene in embl/genbank. the results showed that eight nucleotides and seven amino acid residues were ... | 2003 | 16276913 |
| [characterization of insecticidal crystal proteins genes from bacillus thuringiensis 4.0718 strain]. | in this study, we rapidly identified bacillus thuringiensis 4.0718 strain that harbored the known cryl and cry2 type genes by a pcr strategy. three pairs of universal oligonucleotide primers were designed to detect all known cry1, cry2 and cry3 type gene sequences. then the dna of the positive strain 4.0718 was probed with a set of specific primers. one feature of this screening method was that each gene was expected to produce a pcr product having a precise molecular weight. pcr products having ... | 2003 | 16279211 |
| occurrence and diversity of mosquitocidal strains of bacillus thuringiensis. | ever since the discovery of the first bacillus thuringiensis strain capable of killing mosquito larvae, namely, b. thuringiensis var israelensis, there are several reports from different parts of the world about the occurrence of mosquitocidal strains belonging to different subspecies/serotypes numbering thirty-six. the main sources of these wild type strains are soils/sediments, plants, animal feces, sick/moribund insects and waters. the toxicity of the strains within a subspecies/serotype vari ... | 2005 | 16294805 |
| monitoring of insecticides resistance in main malaria vectors in a malarious area of kahnooj district, kerman province, southeastern iran. | kahnooj district in south of iran is an endemic area for malaria where anopheles stephensi (liston) is a main malaria vector and an. dthali (patton) a secondary vector. according to the national strategy plan on monitoring of insecticides resistance, this study was performed on susceptibility and irritability levels of an. stephensi and an. dthali to different insecticides in the district. | 2005 | 16294808 |
| efficacy of a bacillus thuringiensis israelensis tablet formulation, vectobac dt, for control of dengue mosquito vectors in potable water containers. | vectobac dt, a tablet formulation of bacillus thuringiensis israelensis (bti) was evaluated for the potential control of dengue vectors in various types of potable water containers. on introduction to containers, the tablet sinks to the bottom and the bti toxins are found concentrated at the sides and the base, while the treated water column is free of bti toxins within 24 hours after tablet introduction. in a simulated study, earthen, hdpe and plastic containers were kept covered and laboratory ... | 2005 | 16295540 |
| thermal resistance of spores from virulent strains of bacillus anthracis and potential surrogates. | the objective of this study was to determine the thermal resistance of spores of bacillus anthracis and potential surrogates. the heat resistance of spores suspended in buffer (ph 7.0 or 4.5), milk, or orange juice was determined at 70, 80, and 90 degrees c. d-values for b. anthracis strains sterne, vollum, and pasteur ranged from < 1 min at 90 degrees c to approximately 200 min at 70 degrees c and were lower under acidic than under neutral conditions. the d-values for b. anthracis spores fell w ... | 2005 | 16300074 |
| event specific qualitative and quantitative polymerase chain reaction detection of genetically modified mon863 maize based on the 5'-transgene integration sequence. | because of the genetically modified organisms (gmos) labeling policies issued in many countries and areas, polymerase chain reaction (pcr) methods were developed for the execution of gmo labeling policies, such as screening, gene specific, construct specific, and event specific pcr detection methods, which have become a mainstay of gmos detection. the event specific pcr detection method is the primary trend in gmos detection because of its high specificity based on the flanking sequence of the e ... | 2005 | 16302741 |
| precaution and participatory integrated assessment of gm crops in spain. | qualitative participatory integrated assessment (pia) has been carried out to unveil the different accounts and uses of the precautionary principle and of the precautionary approach in the management of bt commercial crops in spain. in particular, two main interpretations have been identified: a case by case precaution (or caution) and a systemic precaution. three scenarios on the plausible causes and consequences of commercial gm crops policy futures and the role of the precautionary principle ... | 2005 | 16304942 |
| a novel 29-kda crystal protein from bacillus thuringiensis induces caspase activation and cell death of jurkat t cells. | bacillus thuringiensis, the most successful and most widely used microbial insecticide, produces crystal proteins. the physiological significance of the crystal proteins is poorly understood except for the potent insecticidal activity. in this paper, we report a novel biological activity of the crystal protein. a 29-kda crystal protein, p29, produced by b. thuringiensis subsp. coreanensis a1519, was toxic to jurkat, a cell line from human leukemic t cells. upon treatment of the jurkat cells with ... | 2005 | 16306686 |
| synergistic interaction between beauveria bassiana- and bacillus thuringiensis tenebrionis-based biopesticides applied against field populations of colorado potato beetle larvae. | commercial biopesticides based on the fungal pathogen beauveria bassiana strain gha and the bacterial pathogen bacillus thuringiensis tenebrionis were applied alone and in combination (tank mixed) against larval populations of the colorado potato beetle, leptinotarsa decemlineata, in small plots of potatoes over three field seasons. interactions between the two products were evaluated in terms of pest-control efficacy. b. bassiana (formulated as mycotrol) was applied at low and medium label rate ... | 2005 | 16307755 |
| efficient solubilization, activation, and purification of recombinant cry45aa of bacillus thuringiensis expressed as inclusion bodies in escherichia coli. | a cytotoxic protein cry45aa of bacillus thuringiensis expressed as inclusion bodies in escherichia coli was solubilized in 10 mm hcl. protein concentration of saturated solution of the recombinant cry45aa in 10 mm hcl was about 25 times higher than that in the buffer of previous method (in 50 mm sodium carbonate buffer, ph 10.5, containing 1 mm edta, and 10 mm dithiothreitol). the cry45aa solubilized in the acidic solution was activated by pepsin as an alternative to proteinase k in the previous ... | 2006 | 16307894 |
| characterization of a cry4ba-type gene of bacillus thuringiensis israelensis and evidence of the synergistic larvicidal activity of its encoded protein with cry2a delta-endotoxin of b. thuringiensis kurstaki on culex pipiens (common house mosquito). | a newly isolated strain of bacillus thuringiensis, named bupm97, was identified as affiliated to the israelensis subspecies. this strain was selected for its insecticidal activity against larvae of several dipteran insects, such as the common house mosquito (culex pipiens). a 5 kb ecori fragment, containing a cry4ba-type gene, named cry4blb, was cloned from bupm97. the sequencing of this gene revealed an open reading frame of 3411 bp encoding a protein of 1136 amino acid residues. similarity ana ... | 2006 | 16309381 |
| consequences for protaphorura armata (collembola: onychiuridae) following exposure to genetically modified bacillus thuringiensis (bt) maize and non-bt maize. | studies on the effect of genetically modified bacillus thuringiensis (bt) crops on true soil dwelling non-target arthropods are scarce. the objective of this study was to assess the influence of a 4-week exposure to two bt maize varieties (cry1ab) cascade and meb307 on the collembolan protaphorura armata. for comparison three non-bt maize varieties, rivaldo (isogenic to cascade), monumental (isogenic to meb307) and dk242, and two control diets based on baker's yeast (uncontaminated and contamina ... | 2006 | 16310913 |
| the molecular structure and catalytic mechanism of a quorum-quenching n-acyl-l-homoserine lactone hydrolase. | in many gram-negative bacteria, including a number of pathogens such as pseudomonas aeruginosa and erwinia carotovora, virulence factor production and biofilm formation are linked to the quorum-sensing systems that use diffusible n-acyl-l-homoserine lactones (ahls) as intercellular messenger molecules. a number of organisms also contain genes coding for lactonases that hydrolyze ahls into inactive products, thereby blocking the quorum-sensing systems. consequently, these enzymes attract intense ... | 2005 | 16314577 |
| evaluating the induced-odour emission of a bt maize and its attractiveness to parasitic wasps. | the current discussion on the safety of transgenic crops includes their effects on beneficial insects, such as parasitoids and predators of pest insects. one important plant trait to consider in this context is the emission of volatiles in response to herbivory. natural enemies use the odours that result from these emissions as cues to locate their herbivorous prey and any significant change in these plant-provided signals may disrupt their search efficiency. there is a need for practical and re ... | 2005 | 16315088 |
| [the role of succinate dehydrogenase in bacterial resistance to the delta endotoxins of bacillus thuringiensis]. | 2005 | 16315992 | |
| decolourisation and detoxification of synthetic molasses melanoidins by individual and mixed cultures of bacillus spp. | the decolourisation of synthetic melanoidins (i.e., gga, gaa, sga, and saa) by three bacillus isolates (bacillus thuringiensis (mtcc 4714), bacillus brevis (mtcc 4716) and bacillus sp. (mtcc 6506)) was studied. significant reduction in the values of physicochemical parameters was noticed alongwith the decolourisation of all four melanoidins (10% v/v). b. thuringiensis (mtcc 4714) caused maximum decolourisation followed by b. brevis (mtcc 4716) and bacillus sp. (mtcc 6506). a mixed culture compri ... | 2006 | 16321521 |
| efficient growth inhibition of bacillus anthracis by knocking out the ribonucleotide reductase tyrosyl radical. | bacillus anthracis, the causative agent of anthrax, is a worldwide problem because of the need for effective treatment of respiratory infections shortly after exposure. one potential key enzyme of b. anthracis to be targeted by antiproliferative drugs is ribonucleotide reductase. it provides deoxyribonucleotides for dna synthesis needed for spore germination and growth of the pathogen. we have cloned, purified, and characterized the tyrosyl radical-carrying nrdf component of b. anthracis class i ... | 2005 | 16322104 |
| low persistence of bacillus thuringiensis serovar israelensis spores in four mosquito biotopes of a salt marsh in southern france. | we studied the persistence of bacillus thuringiensis serovar israelensis (bti) in a typical breeding site of the mosquito ochlerotatus caspius in a particularly sensitive salt marsh ecosystem following two bti-based larvicidal applications (vectobac 12as, 1.95 l/ha). the treated area was composed of four larval biotopes that differed in terms of the most representative plant species (sarcocornia fruticosa, bolboschoenus maritimus, phragmites australis, and juncus maritimus) and the physical and ... | 2005 | 16328650 |
| spatial variation in bacillus thuringiensis/cereus populations within the phyllosphere of broad-leaved dock (rumex obtusifolius) and surrounding habitats. | the aim of this study was to determine the prevalence and toxin gene diversity of bacillus thuringiensis/b. cereus in the phyllosphere of broad-leaved dock (rumex obtusifolius) at a small spatial scale. b. thuringiensis/cereus populations were isolated from the phyllosphere of dock and neighbouring grass and in neighbouring soil using commercially available selective media which avoided the disadvantageous heat-shock selection procedure. the maximum density of b. thuringiensis/cereus in the dock ... | 2005 | 16332339 |
| distribution of genes encoding putative virulence factors and fragment length polymorphisms in the vrra gene among brazilian isolates of bacillus cereus and bacillus thuringiensis. | one hundred twenty-one strains of the bacillus cereus complex, of which 80 were isolated from a variety of sources in brazil, were screened by pcr for the presence of sequences (bcet, hbla, nhebc, plc, sph, and vip3a) encoding putative virulence factors and for polymorphisms in variable-number tandem repeats (vntr), using a variable region of the vrra open reading frame as the target. amplicons were generated from isolates of b. cereus and bacillus thuringiensis for each of the sequences encodin ... | 2005 | 16332792 |
| flha influences bacillus thuringiensis plcr-regulated gene transcription, protein production, and virulence. | bacillus thuringiensis and bacillus cereus are closely related. b. thuringiensis is well known for its entomopathogenic properties, principally due to the synthesis of plasmid-encoded crystal toxins. b. cereus appears to be an emerging opportunistic human pathogen. b. thuringiensis and b. cereus produce many putative virulence factors which are positively controlled by the pleiotropic transcriptional regulator plcr. the inactivation of plcr decreases but does not abolish virulence, indicating th ... | 2005 | 16332888 |
| rapid ped-2e9 cell-based cytotoxicity analysis and genotyping of bacillus species. | bacillus species causing food-borne disease produce multiple toxins eliciting gastroenteritis. toxin assays with mammalian cell cultures are reliable but may take 24 to 72 h to complete and also lack sensitivity. here, a sensitive and rapid assay was developed using a murine hybridoma ped-2e9 cell model. bacillus culture supernatants containing toxins were added to a ped-2e9 cell line and analyzed for cytotoxicity with an alkaline phosphatase release assay. most bacillus cereus strains produced ... | 2005 | 16333068 |
| bollworm resistance to bt cotton in india. | 2005 | 16333282 | |
| cloning and characterization of a novel gene cry9ec1 encoding lepidopteran-specific parasporal inclusion protein from a bacillus thuringiensis serovar galleriae strain. | a novel delta-endotoxin gene from a lepidopteran-specific bacillus thuringiensis serovar galleriae strain was cloned, and the full sequence of the cry gene was determined. the cloned 6.5-kb dna fragment included the full sequence of the cry gene and three open reading frames located upstream of the cry gene. the gene, designated cry9ec1, encodes a polypeptide of 1154 amino acid residues with a predicted molecular weight of 130 237. the deduced amino acid sequence of the cry9ec1 protein had the h ... | 2005 | 16333339 |
| new tool for spreading proteins to the environment: cry1ab toxin immobilized to bioplastics. | a new tool to provide an environmentally friendly way to deliver active proteins to the environment has been developed, based on the use of polyhydroxyalkanoate (pha, bioplastic) granules. to illustrate this novel approach, a derived cry1ab insect-specific toxin protein was in vivo immobilized into pha granules through the polypeptide tag biof. the new toxin, named fk-bt1, was shown to be active against sesamia nonagrioides (lepidoptera: noctuidae). the dose-mortality responses of the new toxin ... | 2006 | 16333620 |
| development of a bacillus thuringiensis-based assay on lygus hesperus. | lygus hesperus knight (hemiptera: miridae) is an economically important insect pest controlled primarily by chemical pesticides. bacillus thuringiensis berliner is a gram-positive bacterium, which upon sporulation produces a parasporal inclusion body, the crystal. the latter, in some strains, exhibits specific insecticidal activities against lepidopteran, coleopteran, or dipteran pests. the aim of the present work was to develop a bacillus thuringiensis-based assay on l. hesperus. several factor ... | 2005 | 16334312 |
| spray-dried bacillus thuringiensis serovar israelensis formulations for control of aedes aegypti larvae. | suspensions containing 0.25 and 1.25 g/liter of bacillus thuringiensis subsp. israelensis (bti) spore-toxin complex were spray-dried by using maltodextrin de-6, corn starch, and nixtamalized corn flour (25 g/liter) as materials to entrap active delta-endotoxin. the inlet air temperature of the drier was kept constant at 141 degrees c and the outlet temperature was maintained at 60 or 70 degrees c. the probit analysis of the concentration-mortality response of third instars of aedes aegypti (l.) ... | 2005 | 16334315 |
| avidin, a potential biopesticide and synergist to bacillus thuringiensis toxins against field crop insects. | a meridic diet was supplemented with avidin at various concentrations to determine its effects on growth and mortality of three lepidopteran insects: helicoverpa zea (boddie), spodoptera exigua (hübner), and anticarsia gemmatalis (hübner). all insects were placed on diet immediately after hatching and observed until death or pupation occurred. at a concentration of 10 ppm, avidin had little or no effect on growth and mortality compared with the control. however at a concentration of 100 ppm almo ... | 2005 | 16334325 |
| western corn rootworm (coleoptera: chrysomelidae) beetle emergence from weedy cry3bbl rootworm-resistant transgenic corn. | three greenhouse experiments were conducted to evaluate western corn rootworm, diabrotica virgifera virgifera leconte, beetle emergence from individual pots containing glyphosate-tolerant transgenic corn, zea mays l., expressing the cry3bbl endotoxin from the soil bacterium bacillus thuringiensis berliner (mon863), nontransgenic glyphosate-tolerant isoline corn, grassy weeds (giant foxtail, setariafaberi r.a.w. herrm; and large crabgrass, digitaria sanguinalis (l.) scop.), and combinations there ... | 2005 | 16334339 |
| field and laboratory studies on water conditions affecting the potency of vectobac (bacillus thuringiensis serotype h-14) against larvae of the blackfly, simulium damnosum. | river water conditions that might influence the efficacy of vectobac, a formulation of the microbial insecticide bacillus thuringiensis h-14 berliner against simulium damnosum sensu lato theobald (diptera: simuliidae) larvae were investigated. a standard formulation was assayed 130 times over 15 months using a mini-gutter system at a field station beside the river pra in ghana. the lethal concentration (lc) values, river temperature, conductivity, turbidity and ph were analysed using univariate ... | 2005 | 16336305 |
| recombinant production of bacterial toxins and their derivatives in the methylotrophic yeast pichia pastoris. | the methylotrophic yeast pichia pastoris is a popular heterologous expression host for the recombinant production of a variety of prokaryotic and eukaryotic proteins. the rapid emergence of p. pastoris as a robust heterologous expression host was facilitated by the ease with which it can be manipulated and propagated, which is comparable to that of escherichia coli and saccharomyces cerevisiae. p. pastoris offers further advantages such as the tightly-regulated alcohol oxidase promoter that is p ... | 2005 | 16336647 |
| brush border membrane binding properties of bacillus thuringiensis vip3a toxin to heliothis virescens and helicoverpa zea midguts. | the binding properties of vip3a, a new family of bacillus thuringiensis insecticidal toxins, have been examined in the major cotton pests, heliothis virescens and helicoverpa zea. vip3a bound specifically to brush border membrane vesicles (bbmv) prepared from both insect larval midguts. in order to examine the cross-resistance potential of vip3a to the commercially available cry1ac and cry2ab2 toxins, the membrane binding site relationship among these toxins was investigated. competition binding ... | 2006 | 16337146 |
| an immuno-pcr method for detecting bacillus thuringiensis cry1ac toxin. | the cry1ac toxin is an insecticidal protein produced by bacillus thuringiensis var. kurstaki. recently, the gene encoding the toxin was genetically transformed into crop plants. a specific and sensitive method for detecting the cry1ac toxin would facilitate monitoring for this protein in crop and non-crop plants and also in foods. the purpose of this study was to develop an immuno-pcr technique for detecting this toxin. immuno-pcr combines the specificity of an elisa reaction with the sensitivit ... | 2006 | 16337224 |
| membrane proteins modulate the bilayer curvature in the bacterial virus bam35. | biological membranes control the flow of molecules into and out of cells, and they transmit information about the milieu. structural studies of membrane-containing viruses provide one way to study these membranes in situ. cryo-electron microscopy and image reconstruction of bacteriophage bam35 to 7.3 a resolution revealed a membrane bilayer constrained within an icosahedrally symmetric pseudo t = 25 capsid. a total of 60 large transmembrane protein complexes affect the curvature and thickness of ... | 2005 | 16338410 |
| bacillus thuringiensis subsp. israelensis cyt1aa synergizes cry11aa toxin by functioning as a membrane-bound receptor. | bacillus thuringiensis subsp. israelensis produces crystal proteins, cry (4aa, 4ba, 10aa, and 11aa) and cyt (1aa and 2ba) proteins, toxic to mosquito vectors of human diseases. cyt1aa overcomes insect resistance to cry11aa and cry4 toxins and synergizes the toxicity of these toxins. however, the molecular mechanism of synergism remains unsolved. here, we provide evidence that cyt1aa functions as a receptor of cry11aa. sequential-binding analysis of cyt1aa and cry11aa revealed that cyt1aa binding ... | 2005 | 16339907 |
| incorporation of specific fatty acid precursors during spore germination and outgrowth in bacillus thuringiensis. | the selective incorporation of precursors specific for individual fatty acids in germinating and outgrowing spores of bacillus thuringiensis is described. the specific precursors utilized were [c]butyrate, -isobutyrate, -valerate, and -isovalerate, which were incorporated into even-numbered normal-chain isomers, even-numbered iso-isomers, odd-numbered normal-chain acids, and odd-numbered isohomologs, respectively. this preferential incorporation by b. thuringiensis allows the terminal carbons of ... | 1980 | 16345590 |
| some effects of douglas fir terpenes on certain microorganisms. | the douglas fir terpene alpha-pinene was shown to inhibit the growth of a variety of bacteria and a yeast. other terpenes of the douglas fir, including limonene, camphene, and isobornyl acetate, were also inhibitory to bacillus thuringiensis. all terpenes were inhibitory at concentrations normally present in the fir needle diet of douglas fir tussock moth larvae. the presence of such terpenes in the diet of these insects was found to strongly influence the infectivity of b. thuringiensis spores ... | 1980 | 16345609 |
| rocket immunoelectrophoresis of the entomocidal parasporal crystal of bacillus thuringiensis subsp. kurstaki. | rocket immunoelectrophoresis was used to quantitate the soluble parasporal crystal of bacillus thuringiensis subsp. kurstaki. the method described is rapid, reliable, specific, and extremely accurate, and it can be used to measure crystal toxin in commercial microbial insecticides that contain a mixture of spores, vegetative cells, and carrier materials. | 1980 | 16345656 |
| toxicity of bacillus thuringiensis spo cr mutants for the european corn borer ostrinia nubilalis. | inclusion bodies isolated from spo cr mutants of bacillus thuringiensis were toxic for larvae of the european corn borer. probit analysis revealed comparable toxicity between wild-type crystals (isolated from b. thuringiensis subsp. kurstaki) and crystals produced from two spore-free mutants of the same subspecies. death of the larvae was due to starvation, presumably through delta-endotoxin-induced gut paralysis. inclusion bodies pretreated with alpha-chymotrypsinogen were equally as toxic as n ... | 1981 | 16345839 |
| purification of poly-beta-hydroxybutyrate by density gradient centrifugation in sodium bromide. | fractionation of fully sporulated cultures of bacillus thuringiensis by density gradient centrifugation in nabr produced two bands which were identified as poly-beta-hydroxybutyrate. this technique generated high yields of membrane-bound and unbound granules of exceptional purity and degree of polymerization. | 1982 | 16346018 |
| formation of crystalline delta-endotoxin or poly-beta-hydroxybutyric acid granules by asporogenous mutants of bacillus thuringiensis. | parental strains and asporogenous mutants of bacillus thuringiensis subspp. kurstaki and aizawai produced high yields of delta-endotoxin on m medium, which contained 330 mug of potassium per ml, but not on st and st-a media, each of which contained only 11 mug of potassium per ml. on st and st-a media, refractile granules were formed instead. these granules had no insecticidal activity against silkworms and were isolated and identified as poly-beta-hydroxybutyric acid. supplementation of the pot ... | 1982 | 16346040 |
| asporogenous bacillus thuringiensis mutant producing high yields of delta-endotoxin. | an asporogenous bacillus thuringiensis subsp. kurstaki strain ik mutant, strain 290-1, which produced high yields of delta-endotoxin, was obtained by ethyl methane sulfonate treatment of a spore suspension. the mutant strain produced about the same amount of delta-endotoxin as that produced by the parent strain, but 10 to 10 cells did not form any detectable dormant spores. | 1982 | 16346044 |
| dissolution and degradation of bacillus thuringiensis delta-endotoxin by gut juice protease of the silkworm bombyx mori. | the dissolution and degradation of dagger-endotoxin (crystal) of bacillus thuringiensis subsp. kurstaki strain hd-1 were investigated. crystals were dissolved in 0.1 m phosphate-carbonate-naoh buffer at ph > 12. swelling of crystals occurred in the buffer between ph 10 and 11, and crystals dissolved in the same buffer supplemented with gut juice protease of the silkworm bombyx mori. the proteolytic dissolution of crystals occurred after a time lag of several minutes in 0.1 m carbonate-naoh buffe ... | 1983 | 16346206 |
| enzyme-linked immunosorbent assay for quantitative detection of bacillus thuringiensis crystal protein. | accurate measurement of the toxic protein crystal produced during deep-tank fermentation of bacillus thuringiensis is critical for optimum process yield. the currently accepted method is a bioassay that requires more time to generate data than to complete the fermentation itself. a noncompetitive enzyme-linked immunosorbent assay has been developed with purified b. thuringiensis crystals to generate rabbit antiserum. this technique gives a quantitative crystal protein value with a colorimetric e ... | 1983 | 16346207 |
| only part of the protoxin gene of bacillus thuringiensis subsp. berliner 1715 is necessary for insecticidal activity. | [this corrects the article on p. 708 in vol. 49.]. | 1985 | 16346828 |
| composition and toxicity of the inclusion of bacillus thuringiensis subsp. israelensis. | the multisegmented ovoidal inclusion of bacillus thuringiensis subsp. israelensis was found to be composed of two structurally and biochemically distinct components. electron microscopy of the inclusion revealed it to be composed mainly of osmiophobic or lightly stained segments crystallized in a lattice showing a repeat of approximately 4.3 nm. these light segments of the inclusions were shared by osmiophylic darkly stained segments with a crystal lattice repeat of approximately 7.8 nm. the lig ... | 1985 | 16346842 |
| cloning and expression of an insecticidal k-73 type crystal protein gene from bacillus thuringiensis var. kurstaki into escherichia coli. | a 75-kilobase plasmid from bacillus thuringiensis var. kurstaki (hd-244) was associated with the k-73 type insecticidal crystal protein production by mating into b. cereus and subsequent curing of excess plasmids. this plasmid was partially digested with endonuclease r . sau3a and the fragments were cloned into escherichia coli (hb101) on vector pbr322. candidate clones were screened for plasmid vectors which contained the expected insert size (at least 3 kilobases) and then with an enzyme-linke ... | 1985 | 16346882 |
| survival of bacillus thuringiensis spores in soil. | bacillus thuringiensis spores and parasporal crystals were incubated in natural soil, both in the laboratory and in nature. during the first 2 weeks, the spore count decreased by approximately 1 log. thereafter, the number of spore cfu remained constant for at least 8 months. b. thuringiensis did not lose its ability to make the parasporal crystals during its residence in soil. spore survival was similar for a commercial spore-crystal preparation (the insecticide) and for laboratory-grown spores ... | 1985 | 16346949 |
| isolation and characterization of coproporphyrin produced by four subspecies of bacillus thuringiensis. | it was found by using spectrophotometric, spectrofluorometric, and high-pressure liquid chromatography that four subspecies of bacillus thuringiensis produce coproporphyrin. the porphyrin isomer was identified as coproporphyrin i for b. thuringiensis subsp. kurstaki (hd1). the porphyrin was isolated both from spores and from a variety of spent growth media. the quantity of porphyrin released by each bacillus subspecies differed. the rank order of porphyrin production follows: b. thuringiensis su ... | 1986 | 16347008 |
| mode of action of bipyramidal delta-endotoxin of bacillus thuringiensis subsp. kurstaki hd-1. | the mode of action of the toxic fragment (p-59) derived from bipyramidal-shaped delta-endotoxin of bacillus thuringiensis subsp. kurstaki hd-1 on the silkworm bombyx mori was investigated. an enzyme-linked immunosorbent assay showed that there was no translocation of p-59 from the gut lumen to the hemocoel. when membrane vesicles prepared from silkworm midgut were incubated with p-59, normally smooth surface of vesicles became rough, and patch formation was observed on the surface. vesicles trea ... | 1986 | 16347024 |
| ingestion and adsorption of bacillus thuringiensis subsp. israelensis by gammarus lacustris in the laboratory. | several groups of gammarus lacustris adults were exposed to solutions containing 0.5 and 5.0 mg of bacillus thuringiensis subsp. israelensis per liter for 1- or 24-h periods by using traditional static bioassay exposure procedures. during a postexposure holding period, fecal pellets were removed and plated on tryptic soy agar to determine b. thuringiensis subsp. israelensis spore content. the experiments verified that traditional exposure procedures assure ingestion of b. thuringiensis subsp. is ... | 1986 | 16347242 |
| toxic trypsin digest fragment from the bacillus thuringiensis parasporal protein. | enzymatic digestion in vitro of the bacillus thuringiensis protoxin presumably releases and activates the toxin in a manner analogous to that which occurs when a b. thuringiensis sporulated fermentation preparation passes through the midgut of a lepidopteran larva. therefore, a sporulated culture of b. thuringiensis subsp. kurstaki (serotype 3a3b) hd-263 was treated with trypsin to release an activated toxin soluble in bicarbonate buffer. a 63-kilodalton protein, toxic to cabbage looper larvae ( ... | 1987 | 16347290 |
| specificity of bacillus thuringiensis delta-endotoxin. | the insecticidal activity of the delta-endotoxins of 14 bacillus thuringiensis strains belonging to 12 subspecies was determined against pieris brassicae, heliothis virescens, and spodoptera littoralis. larvae of p. brassicae were highly susceptible to purified crystals of strains of b. thuringiensis subsp. thuringiensis and b. thuringiensis subsp. morrisoni, whereas h. virescens responded best to b. thuringiensis subsp. kenyae and b. thuringiensis subsp. kurstaki. the crystals of the b. thuring ... | 1987 | 16347299 |
| fate of bacillus thuringiensis subsp. israelensis under simulated field conditions. | the fate of bacillus thuringiensis subsp. israelensis in a natural aquatic habitat was studied in a model system by using laboratory-simulated field waters and a mutant of the bacterium resistant to three antibiotics. contact with mud of a sporal culture of the mutant resulted in an immediate disappearance of the larvicidal activity but had no influence on viability. the cessation of toxicity was caused by bacterial adsorption on soil particles, since 99.8% of the bacteria was found in the mud f ... | 1987 | 16347326 |
| selective process for efficient isolation of soil bacillus spp. | we were able to isolate bacillus thuringiensis from environmental samples with a background of 10 bacteria per g of soil. our selection process differed significantly from classical selection methods which permit only the desired organism to grow. in our process, germination of b. thuringiensis spores was selectively inhibited by sodium acetate, while most of the undesired sporeformers germinated. next, all of the nonsporulated microbes were eliminated by heat treatment at 80 degrees c for 3 min ... | 1987 | 16347359 |
| monoclonal antibody analysis and insecticidal spectrum of three types of lepidopteran-specific insecticidal crystal proteins of bacillus thuringiensis. | we have investigated the protein composition and the insecticidal spectrum of crystals of 29 bacillus thuringiensis strains active against lepidopteran larvae. all crystals contained proteins of 130 to 140 kilodaltons (kda) which could be grouped into three types by the molecular weight of the protoxin and the trypsin-activated core fragment. proteins of the three types showed a characteristic insecticidal spectrum when tested against five lepidopteran species. type a crystal proteins were proto ... | 1988 | 16347711 |
| response in soil of cupriavidus necator and other copper-resistant bacterial predators of bacteria to addition of water, soluble nutrients, various bacterial species, or bacillus thuringiensis spores and crystals. | soil was incubated with various species of bacteria, bacillus subtilis, or bacillus thuringiensis spores and crystals. these were added to serve as potential prey for indigenous, copper-resistant, nonobligate bacterial predators of bacteria in the soil. alternatively, the soil was incubated with soluble nutrients or water only to cause potential indigenous prey cells to multiply so the predator cells would multiply. all of these incubation procedures caused excessive multiplication of some gram- ... | 1988 | 16347727 |
| identification of a delta-endotoxin gene product specifically active against spodoptera littoralis bdv. among proteolysed fractions of the insecticidal crystals of bacillus thuringiensis subsp. aizawai 7.29. | at least three different insecticidal crystal protein genes were shown to be expressed in bacillus thuringiensis subsp. aizawai 7.29, a strain that is potentially active against the cotton leafworm spodoptera littoralis bdv. among crude k-60 fractions (60- to 70-kilodalton [kda] molecules) that were products of proteolysed crystals containing the active domains of the protoxin molecules, we were able to distinguish several distinct components on the basis of their antigenic relationship and thei ... | 1988 | 16347771 |
| separation of protein crystals from spores of bacillus thuringiensis by ludox gradient centrifugation. | a method is described for the purification of bacillus thuringiensis protein crystals by ludox gradient centrifugation. this method is simple, inexpensive, fast, and efficient compared with other techniques. it has been successfully used to purify and characterize the protein crystals from several b. thuringiensis strains. | 1989 | 16347918 |
| protozoan response to the addition of bacterial predators and other bacteria to soil. | representatives of several categories of bacteria were added to soil to determine which of them might elicit responses from the soil protozoa. the various categories were nonobligate bacterial predators of bacteria, prey bacteria for these predators, indigenous bacteria that are normally present in high numbers in soil, and non-native bacteria that often find their way in large numbers into soil. the soil was incubated and the responses of the indigenous protozoa were determined by most-probable ... | 1989 | 16347983 |
| worldwide abundance and distribution of bacillus thuringiensis isolates. | we found the insect control agent bacillus thuringiensis to be a ubiquitous soil microorganism. using acetate selection to screen soil samples, we isolated b. thuringiensis in 785 of 1,115 soil samples. these samples were obtained in the united states and 29 other countries. a total of 48% of the b. thuringiensis isolates (8,916 isolates) fit the biochemical description of known varieties, while 52% represented undescribed b. thuringiensis types. over 60% (1,052 isolates) of the isolates tested ... | 1989 | 16348022 |
| a translation fusion product of two different insecticidal crystal protein genes of bacillus thuringiensis exhibits an enlarged insecticidal spectrum. | two truncated bacillus thuringiensis crystal protein genes, belonging to the classes cryia(b) and cryic and both coding for insecticidal n-terminal fragments of the corresponding crystal proteins, were translationally fused. expression of the gene fusion in escherichia coli showed a biologically active protein with a toxicity spectrum that overlapped those of both contributing crystal proteins. | 1990 | 16348153 |
| interactions between bacillus thuringiensis subsp. israelensis and fathead minnows, pimephales promelas rafinesque, under laboratory conditions. | interactions between bacillus thuringiensis subsp. israelensis and fathead minnows, pimephales promelas, were studied in laboratory exposures to two commercial formulations, vectobac-g and mosquito attack. mortality among fatheads exposed to 2.0 x 10 to 6.5 x 10 cfu/ml with both formulations was attributed to severe dissolved oxygen depletion due to formulation ingredients rather than to direct toxicity from the parasporal crystal. no adverse effects were observed at 6.4 x 10 cfu/ml and below. f ... | 1990 | 16348271 |
| insecticidal activity of a bacterial crystal protein expressed by a recombinant baculovirus in insect cells. | baculoviruses are insect pathogens with a relatively slow speed of action, and this has limited their use as control agents of insect pests. introduction into baculoviruses of genes which code for proteins interfering specifically with insect metabolism or metamorphosis, such as toxins, hormones, and enzymes, may enhance the pathogenicity of these viruses. the complete insecticidal crystal protein gene cryia(b) of bacillus thuringiensis subsp. aizawai 7.21 was engineered into the nuclear polyhed ... | 1990 | 16348284 |
| limiting an insect infestation of nitrogen-fixing root nodules of the pigeon pea (cajanus cajan) by engineering the expression of an entomocidal gene in its root nodules. | a region of dna which determined the production of the insecticidal toxin of bacillus thuringiensis subsp. israelensis was cloned into a derivative of a broad-host-range group incq plasmid vector of gram-negative bacteria. the plasmid which we constructed was transferred by conjugative mobilization into a bradyrhizobium species that nodulates pigeon peas. in this species the construction was maintained stably in the absence of selection and expressed the gene that was installed. experiments in a ... | 1990 | 16348294 |