Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| location of a lepidopteran specificity region in insecticidal crystal protein cryiia from bacillus thuringiensis. | the bacillus thuringiensis insecticidal crystal protein cryiia has both high mosquito activity and gypsy moth activity; in contrast cryiib, which is 87% homologous, displays no mosquito activity and has a three-fold lower gypsy moth activity. the regions responsible for specificity against gypsy moth (lymantria dispar) and mosquito (aedes aegypti) larvae were located by introducing mlui and xhoi sites into homologous positions within the putative domain ii of both cryiia and cryiib genes, which ... | 1994 | 7997170 |
| ligand blot identification of a manduca sexta midgut binding protein specific to three bacillus thuringiensis cryia-type icps. | the cryia(a), cryia(b) and cryia(c) bacillus thuringiensis insecticidal crystal proteins (icps) were used in ligand-blot experiments to detect specific binding proteins in brush-border membrane vesicles (bbmv) of manduca sexta. we identified a protein which binds these three cryia-type icps. the apparent molecular mass of the protein, estimated on sds-page, was 210 kda as was the cryia(b) binding protein previously described by vadlamudi and col. we have also demonstrated, in ligand blot experim ... | 1994 | 8003015 |
| intracellular proteolysis and limited diversity of the bacillus thuringiensis cryia family of the insecticidal crystal proteins. | the current concept of how the highly homologous bacillus thuringiensis insecticidal crystal protein genes (cry genes) evolved is through recombination among themselves. the cryia gene family, which is more than 80% identical, consists of only three known genes, even through they are often found together in the same bacterium. to examine the lack of diversity among these genes, recombinatorial chimeric protein toxin genes were constructed and transformed into e. coli, b. subtilis, and b. thuring ... | 1994 | 8003016 |
| effect of bacillus thuringiensis beta exotoxin on ultrastructures of midgut cells of culex sitiens. | in midgut cells of culex sitiens intoxicated with beta exotoxin of bacillus thuringiensis, the microvilli are greatly reduced. in the cytoplasm there is progressive disarrangement of the membranes of the rough endoplasmic reticulum, first to spherules, and later to a granular mass. minute vacuoles appearing in the cytoplasm are parts of the distorted labyrinth and remains of the golgi membranes. there is no disintegration of the outer cell membrane, and no hypertrophy of goblet cells. nuclei rem ... | 1994 | 8005002 |
| high-density cultivation of sporeformers. | sporeformers are sources of a large number of industrially important biological products including enzymes, antibiotics, and bioinsecticides. cultivation of these microorganisms to high cell densities offers potential for enhancing the rates of formation as well as the concentration of the desired products in the fermentation broths in bioreactors. with this objective, investigations have been carried out involving fed-batch cultivation of bacillus thuringiensis, which is known to produce an ins ... | 1994 | 8010682 |
| analysis of non-active engineered bacillus thuringiensis crystal proteins. | crystal proteins of bacillus thuringiensis are known for their insecticidal specificity. this specificity is, to a large extent, determined by the interaction of the proteins with high-affinity binding sites on the epithelial membrane of the midgut of sensitive insects. in particular, domain ii of the three domains of the toxic moiety has been implicated in specificity. to determine which sequences of the protein are involved in binding, loops of domain ii which terminate in the molecular apex o ... | 1994 | 8013868 |
| fixed-wing, aerial application of liquid bacillus thuringiensis h-14 (acrobe) for control of spring aedes mosquitoes in michigan. | liquid bacillus thuringiensis h-14 (acrobe) was applied from fixed-wing aircraft at a rate of 4.68 liters of water-insecticide mixture (1.17 liter concentrate) per hectare to woodland pools in michigan. a post-treatment larval survey indicated an 88.5% reduction in aedes species larvae. a volume median diameter of 208 microns was determined. | 1994 | 8014627 |
| [laboratory studies of the usefulness of biopreparation dipel in reducing the german cockroach (blattella germanica l.) population]. | in the studies conducted for finding of biological factors effectively controlling insects of hygienic importance german cockroaches were subjected to the action of an insecticide containing spores of bacillus thuringiensis var. kurstaki. one gram of the insecticide contained 25 miliard (us billion) spores with protein endotoxin crystals. the insects were given drinking water and food containing 1.0%, 0.5%, 0.25%, 0.125% of the initial preparation. the experiment was carried out on 1800 cockroac ... | 1993 | 8016546 |
| protozoan-enhanced toxicity of bacillus thuringiensis var. israelensis delta-endotoxin against aedes aegypti larvae. | the toxicity of bacillus thuringiensis var. israelensis (bti) in mosquito larvae was enhanced by encapsulation in the protozoan tetrahymena pyriformis. aedes aegypti larvae which fed on t. pyriformis loaded with bti died about three times faster than when fed on the same concentrations of bti alone due to ingestion of higher toxin concentrations, reflected by shorter death times of exposed populations. the best larvicidal activities were achieved at ratios of cell/spore numbers in the range of 1 ... | 1994 | 8021522 |
| [control of fly larvae in a pig farm by oral administration of thuridan to pigs]. | the studies were carried out in an experimental pig farm on 402 animals with thuridan (spore of delta-endotoxin complex of bacillus thuringiensis kurstaki). it was applied orally, as feed additive in a concentration of 0.1 and 0.5% for three current days. the efficacy of thuridan was established with the use of fly-catchers which were hung in the same places--once before and three times after thuridan had been used. after 3 application of thuridan the number of flies decreased by 88%. | 1994 | 8023511 |
| [the nature of the interrelations of different bacillus thuringiensis serotypes between themselves and other species of the genus bacillus]. | intraspecies interrelations between representatives of 7 serotypes of bacillus thuringiensis, as well as antagonistic interrelations between b. thuringiensis and 130 strains of 16 species of bacillus bacteria were studied. antagonistic activity was determined for 18 strains, representatives of genus bacillus, with respect to b. thuringiensis var. tuviensis. antagonism was the most pronounced between the strains of the alesti serotype and representatives of other serotypes as well as between the ... | 1993 | 8025694 |
| are d- and l-chiro-phosphoinositides substrates of phosphatidylinositol-specific phospholipase c? | derivatives of chiro-inositol have been recently shown to mediate many important biological processes. this work addresses the question of whether phosphatidylinositol-specific phospholipase c (pi-plc) could be involved in the generation of these chiro-inositol derivatives. two diastereomers of the analog of phosphatidylinositol containing 1d- and 1l-chiro-inositol have been synthesized. 1d-2-o-(1,2-o-dipalmitoyl-sn-glycero-3-phospho)-chiro-inositol (1d-chiro-pi) was synthesized in 12 steps star ... | 1994 | 8031771 |
| ph-induced conformational transitions of cry ia(a), cry ia(c), and cry iiia delta-endotoxins in bacillus thuringiensis. | three protoxins and corresponding delta-endotoxins from bacillus thuringiensis (bt) were studied by means of circular dichroism spectroscopy and size-exclusion hplc. at neutral ph, the cry iiia toxin exists only as a 65-kda monomer. the toxins of cry ia(a) and cry ia(c) exist both as 66-kda monomers and as oligomers with apparent molecular masses greater than 220 kda. at neutral ph, interconversion between monomer and oligomer is slow, and the two, separate forms exist for several days. equilibr ... | 1994 | 8031786 |
| [the suitability of bacterial preparations intended for mosquito control in salt water]. | laboratory experiments have brought the authors to a conclusion on the efficacy of b. thuringiensis and b. sphaericus-based insecticides in salty water mosquito breeding sites. species difference of mosquito larvae susceptibility to the insecticides related to salt concentration in water were detected. | 1993 | 8041317 |
| expression in bacillus subtilis of the bacillus thuringiensis cryiiia toxin gene is not dependent on a sporulation-specific sigma factor and is increased in a spo0a mutant. | expression of the bacillus thuringiensis cryiiia gene encoding a coleoptera-specific toxin is weak during vegetative growth and is activated at the onset of the stationary phase. cryiiia'-'lacz fusions and primer extension analysis show that the regulation of cryiiia expression is similar in bacillus subtilis and in b. thuringiensis. activation of cryiiia expression was not altered in b. subtilis mutant strains deficient for the sigma h and sigma e sporulation-specific sigma factors or for minor ... | 1994 | 8045904 |
| overexpression of bacillus thuringiensis hkna, a histidine protein kinase homology, bypasses early spo mutations that result in cryiiia overproduction. | the bacillus thuringiensis cryiiia insecticidal crystal protein (icp) is a vegetatively expressed protein that is toxic to coleopteran insect larvae. sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the asporogenous b. thuringiensis subsp. morrisoni strain eg1351, which harbors the native cryiiia-encoding 88-mda plasmid, showed a 2.5-fold overproduction of the cryiiia protein compared with that of an isogenic wild-type strain. further studies showed that neither cryiiia prot ... | 1994 | 8045905 |
| tn5401 disruption of the spo0f gene, identified by direct chromosomal sequencing, results in cryiiia overproduction in bacillus thuringiensis. | the bacillus thuringiensis spo0f gene was identified by chromosomal dna sequencing of sporulation mutants derived from a b. thuringiensis transposon insertion library. a spo0f defect in b. thuringiensis, which was suppressed by multicopy hkna or kina, resulted in the overproduction of the cryiiia insecticidal crystal protein. | 1994 | 8045906 |
| [multiple genes of delta-endotoxins from bacillus thuringiensis subspecies galleriae]. | cloning and expression in e. coli delta-endotoxin genes cryiab7, cryig and, cryix from bacillus thuringiensis ssp galleriae has been performed. restriction mapping and partial sequencing have shown the identity of the 3'-terminal parts of cryig and cryix, although their 5'-terminal halves corresponding to the toxin are unique. sequencing 5'-flanking region of cryix revealed no translation initiation site, which indicates a nonfunctional state of the gene. the clusterized locating of the cryig an ... | 1994 | 8052249 |
| production of antibodies against bacillus thuringiensis delta-endotoxin by injecting its plasmids. | bacillus thuringiensis insecticidal crystalline delta-endotoxin proteins are plasmid encoded. specific antibodies against the delta-endotoxin were obtained in mice and rabbits by injecting isolated b. thuringiensis dna plasmids into their muscles. antibodies could be detected by elisa as early as two weeks after the first injection. they formed immunoprecipitin lines with the toxin in the ouchterlony agarose plate and neutralized the toxicity of the toxin. because no special equipment, delivery ... | 1994 | 8060297 |
| insect tolerance of transgenic populus nigra plants transformed with bacillus thuringiensis toxin gene. | leaves and stem segments of populus nigra were transformed with a. tumefaciens lba4404 harboring a binary vector containing chimeric genes of npt and 35s-omega-b.t. toxin-nos. nineteen regenerated kanamycin resistant plants were analyzed by dna hybridization, out of which 10 were shown to be the candidates of transgenic plants. insect tolerance tests showed that the transgenic plants were toxic to two lepidopteran pests, lymantria dispar l. and apocheimia cinerarius erschoff. based on the result ... | 1993 | 8061230 |
| [hygienic standardization of biological insecticide contents and biological factory waste in soil]. | 1993 | 8063150 | |
| identification of amino acid residues of bacillus thuringiensis delta-endotoxin cryiaa associated with membrane binding and toxicity to bombyx mori. | alanine substitution (a3) or deletion (d3) of residues 365 to 371 of bacillus thuringiensis cryiaa insect toxin removed nearly all toxicity for bombyx mori (> 1,000-fold less active than the wild type). the loss of larvicidal activity in the mutants was not caused by increased sensitivity to larval gut enzymes but could be attributed to significantly reduced binding to b. mori brush border membrane vesicles. some or all of the affected amino acid residues may interact directly or indirectly with ... | 1994 | 8071239 |
| stable immobilization of lipid vesicles for kinetic studies using surface plasmon resonance. | in order to study the kinetics of binding between membrane vesicle surface receptors to the lepidopteran insecticidal toxins from bacillus thuringiensis using surface plasmon resonance, we have developed a technique to immobilize membrane vesicles purified from the brush border of dissected guts from the lepidopteran insect pest choristoneura fumiferana. two methods using immobilized immunoglobulins against either avidin or biotin were successful in achieving stable immobilization of the vesicle ... | 1994 | 8074300 |
| expression of the crystal protein gene under the control of the alpha-amylase promoter in bacillus thuringiensis strains. | the expression of an insecticidal crystal protein gene of bacillus thuringiensis under the control of the alpha-amylase gene promoter was investigated. the cryic gene, which encodes a protein known to have a unique activity against spodoptera (armyworm) species, was used in this investigation. the cryic gene was placed, along with the alpha-amylase promoter from b. subtilis, in a b. thuringiensis-derived cloning vector, generating a pair of recombinant plasmids, psb744 and psb745. the cloning ve ... | 1994 | 8074511 |
| studies on the gpi-anchored enzyme, hepatic 5'-nucleotidase. microheterogeneity of the anchor, processing and localization. | hepatic 5'-nucleotidases of vertebrates were investigated for localization in the lysosomes and the plasma membrane, microheterogeneity of the glycosylphosphatidylinositol (gpi)-anchor moiety and minimal requirement of the c-terminal signal peptide for gpi attachment. using piplc of bacillus thuringiensis and subcellular fractionation by percoll gradient centrifugation, we found that chicken liver 5'-nucleotidase can be transferred from plasma membrane to lysosomes in the gpi-anchored or soluble ... | 1994 | 8081255 |
| osseous plate alkaline phosphatase is anchored by gpi. | alkaline phosphatase activity was released up to 100% from the membrane by using 0.1 u of phosphatidylinositol-specific phospholipase c from b. thuringiensis. the m(r) of solubilized enzyme was 145,000 by sephacryl s-300 gel filtration and 66,000 by sds-page, suggesting a dimeric structure. solubilization of the membrane-bound enzyme with phospholipase c did not destroy its ability to hydrolyze p-nitrophenyl phosphate (pnpp) (264.3 mumol min-1 mg-1),atp (42.0 mumol min-1 mg-1) and pyrophosphate ... | 1994 | 8081265 |
| mutagenesis of two surface-exposed loops of the bacillus thuringiensis cryic delta-endotoxin affects insecticidal specificity. | site-directed mutagenesis was used to determine the role of two surface-exposed loops (gly-317-phe-320 and gln-374-pro-377) in the insecticidal specificity of the bacillus thuringiensis cryic delta-endotoxin. mutant toxins were generated by pcr using degenerate oligonucleotide primers, and expressed in escherichia coli. more than 50 mutant toxins were screened for toxicity to the lepidopteran spodoptera frugiperda sf9 cell line using an in vitro lawn assay. a panel of these mutant toxins, which ... | 1994 | 8093015 |
| effect of rice husbandry on mosquito breeding at mwea rice irrigation scheme with reference to biocontrol strategies. | a study was carried out at mwea rice irrigation scheme, kenya, to assess the impact of rice husbandry on mosquito breeding and identify indigenous biocontrol agents with potential for controlling mosquito breeding in the scheme. the study established a close relationship between the schedule of the farming practices (particularly the flooding phase) and mosquito breeding. two groups of agents, entomopathogenic bacteria (bacillus thuringiensis var. israelensis) and larvivorous fish, were identifi ... | 1993 | 8096871 |
| application of bactoculicide (bacillus thuringiensis h-14) for controlling mosquito breeding in industrial scrap at bhel, hardwar (u.p.). | bactoculicide (bacillus thuringiensis) was evaluated in field trials for controlling mosquito breeding of aedes, culex and anopheles in industrial scraps such as broken heavy machine parts, iron moulds and discarded drums. a dose of 0.5 g/m2 was controlled 96-100% mosquito breeding up to five weeks. | 1993 | 8100539 |
| effect of temperature on toxicity of two bioinsecticides spherix (bacillus sphaericus) and bactoculicide (bacillus thuringiensis) against larvae of four vector mosquitoes. | two bioinsecticide preparations, viz. spherix (bacillus sphaericus) and bactoculicide (bacillus thuringiensis h-14), were tested in the laboratory against larvae of anopheles culicifacies, anopheles stephensi, culex quinquefasciatus and aedes aegypti at different temperatures. the lcs50 of spherix against iii instar larvae of these species at 27 +/- 2 degrees c were 2.0, 0.19, 0.05 and > 40 mg/litre, respectively and those of bactoculicide were 0.32, 0.16, 0.06 and 0.03 mg/litre, respectively. t ... | 1993 | 8100540 |
| [the efficacy of the biological insecticide blp with regard to the larvae of blood-sucking mosquitoes in uzbekistan]. | the efficacy of a biologic larvicidal preparation blp was under study; the insecticide was prepared on the basis of a new strain of b. thuringiensis var. israilensis h-14, isolated from natural material, and its activity to ae. caspiens, c. pipiens, an. hyrcanus larvae was examined. the minimal effective dose of blp used for the treatment of various water bodies is 0.5 kg per 10,000 m2. blp is permitted by the ministry of health and the ministry of fishery of the russian federation for mosquito ... | 1993 | 8101630 |
| pcr analysis of the cryi insecticidal crystal family genes from bacillus thuringiensis. | a method allowing rapid and accurate identification of different subgroups within the insecticidal crystal cryi protein-producing family of bacillus thuringiensis strains was established by using pcr technology. thirteen highly homologous primers specific to regions within genes encoding seven different subgroups of b. thuringiensis cryi proteins were described. differentiation among these strains was determined on the basis of the electrophoretic patterns of pcr products. b. thuringiensis strai ... | 1994 | 8117089 |
| altered protoxin activation by midgut enzymes from a bacillus thuringiensis resistant strain of plodia interpunctella. | processing of bacillus thuringiensis protoxins to toxins by midgut proteinases from a strain of the indianmeal moth, plodia interpunctella (hubner), resistant to b. thuringiensis subspecies entomocidus (hd-198) was slower than that by midgut proteinases from the susceptible parent strain or a strain resistant to b. thuringiensis subspecies kurstaki (hd-1, dipel). midgut extracts from entomocidus-resistant insects exhibited five-fold lower activity toward the synthetic substrate alpha-n-benzoyl-d ... | 1994 | 8117300 |
| membrane interactions and surface hydrophobicity of bacillus thuringiensis delta-endotoxin cryic. | the interaction between bacillus thuringiensis insecticidal delta-endotoxin cryic and phospholipid vesicles was studied by fluorescence spectroscopy. the toxin dissipates the diffusion potential across vesicular membranes, presumably by creating ion permeable channels or pores. this effect is ph-dependent and strongly increases under acidic conditions. the enhanced membrane-perturbing activity of cryic at low ph correlates with the increased surface hydrophobicity of the toxin molecule. the memb ... | 1994 | 8119414 |
| dna relatedness among bacillus thuringiensis serovars. | the genetic relationships of bacillus cereus and of the bacillus thuringiensis serovars were assessed from measurements of dna reassociation. a study of 8 to 10 strains each of 13 of the most commonly encountered serovars revealed that the levels of intragroup dna relatedness for most serovars ranged from 90 to 100%. in contrast, b. thuringiensis serovars canadensis and kenyae consisted of two dna relatedness groups, each of which exhibited levels of intragroup relatedness of 80% or higher and l ... | 1994 | 8123555 |
| differentiation of bacillus anthracis from other bacillus cereus group bacteria with the pcr. | variation among isolates of bacillus anthracis was examined by using restriction fragmentation patterns and the pcr performed with arbitrary and sequence-specific oligonucleotide primers. the patterns were compared with the patterns generated from strains of closely related species belonging to the "bacillus cereus group" of bacteria, including b. cereus, bacillus thuringiensis, and bacillus mycoides. all b. anthracis profiles were identical for each of 18 restriction enzymes, each of 10 arbitra ... | 1994 | 8123566 |
| structure and expression of a gene coding for thermostable alpha-glucosidase with a broad substrate specificity from bacillus sp. sam1606. | we cloned an alpha-glucosidase gene from thermophilic bacillus sp. sam1606 to overexpress it in escherichia coli transformants. deletion of the 5'-noncoding region as well as expression of the alpha-glucosidase gene under the control of the icp promotor of the insecticidal crystal protein gene from bacillus thuringiensis subsp. sotto enhanced the enzyme productivity to 23.5 u/ml, which was 12,000-fold higher than that obtained by the strain sam1606. the open reading frame corresponding to the al ... | 1994 | 8125087 |
| tolerance of sewage treatment plant microorganisms to mosquitocides. | beneficial protozoa and rotifers collected from a wastewater treatment plant in panama city, fl, were tested for tolerance to 11 commonly used mosquito larvicides and adulticides in the laboratory. the acute effects were assessed using selected concentrations of the adulticides fenthion, malathion, naled, permethrin, and resmethrin; and the larvicides bacillus thuringiensis israelensis, bacillus sphaericus, diflubenzuron, larviciding oil, methoprene, and temephos for the following microorganism ... | 1993 | 8126488 |
| [actual and potential possibilities of using delta-endotoxins of bacillus spp. for control of harmful and nuisance insects]. | 1993 | 8128722 | |
| identification of the lipid moiety and further characterization of the novel lipophosphoglycan-like glycoconjugates of trichomonas vaginalis and trichomonas foetus. | the lipid moiety of the lipophosphoglycan (lpg)-like glycoconjugates of trichomonas vaginalis and trichomonas foetus, parasites of the urogenital tract of human and cattle, respectively, has been isolated and characterized by a combination of enzymatic and chemical degradation, chromatography, and mass spectrometry. the carbohydrate composition of the glycan inositol lipid core is also reported. the glycan inositol core of trichomonad glycoconjugates is unique in having more than one glcn and is ... | 1994 | 8135538 |
| cytodifferentiation in tetrahymena vorax is linked to glycosyl-phosphatidylinositol-anchored protein assembly. | the role of glycosyl-ptdins (gpi)-anchored proteins in the cytodifferentiation of tetrahymena vorax was examined. labelling of cells with [3h]myristate or [3h]palmitate followed by electrophoresis showed an array of proteins carrying covalently bound lipids. electrophoresis of protein from cells labelled with the gpi-anchor components [3h]ins and [14c]ethanolamine revealed three polypeptides on fluorograms which have apparent molecular masses of approx. 28, 50 and 82 kda. labelled lipid associat ... | 1994 | 8141785 |
| a mixture of manduca sexta aminopeptidase and phosphatase enhances bacillus thuringiensis insecticidal cryia(c) toxin binding and 86rb(+)-k+ efflux in vitro. | cryia(c) delta-endotoxin, a member of the cryi family of bacillus thuringiensis insecticidal proteins, specifically recognizes and binds with high affinity to target proteins in the midgut of susceptible insects. protein blots of manduca sexta brush-border membranes probed with 125i-cryia(c) identify a major binding protein of 120 kda and a minor binding protein of 65 kda. monoclonal antibodies were raised against the 120-kda toxin binding protein. using isoelectric focusing and monoclonal antib ... | 1994 | 8144508 |
| detection of choristoneura fumiferana brush border membrane-binding molecules specific to bacillus thuringiensis delta-endotoxin by crossed affinity immunoelectrophoresis. | brush border membrane vesicles (bbmvs) prepared from midguts of choristoneura fumiferana larvae were pretreated separately with the three cryia delta-endotoxins from bacillus thuringiensis subsp. kurstaki hd-1. crossed affinity immunoelectrophoresis of the solubilized toxin-bbmv complexes, using antibodies raised against the toxins, revealed at least two peaks for each toxin. all complexes (bbmv bound toxin) migrated in the opposite direction to that of the free toxins. it is concluded that the ... | 1994 | 8147860 |
| haemolytic activity associated with parasporal inclusion proteins of mosquito-specific bacillus thuringiensis soil isolates: a comparative neutralization study. | solubilized parasporal inclusions of the three mosquito-specific bacillus thuringiensis isolates belonging to three different h serovars, co-isolated from a single soil microhabitat, showed haemolytic activity towards mammalian erythrocytes. neutralization tests with antibodies against whole inclusion proteins resulted in crossed neutralization of haemolytic activity among the isolates and the type strain of b. thuringiensis serovar kyushuensis, indicating that the three soil isolates produce to ... | 1994 | 8150264 |
| insecticidal activity of the cryiia protein from the nrd-12 isolate of bacillus thuringiensis subsp. kurstaki expressed in escherichia coli and bacillus thuringiensis and in a leaf-colonizing strain of bacillus cereus. | a 4.0-kb bamhi-hindiii fragment encoding the cryiia operon from the nrd-12 isolate of bacillus thuringiensis subsp. kurstaki was cloned into escherichia coli. the nucleotide sequence of the 2.2-kb acci-hindiii fragment containing the nrd-12 cryiia gene was identical to the hd-1 and hd-263 cryiia gene sequences. expression of cryiia and subsequent purification of cryiia inclusion bodies resulted in a protein with insecticidal activity against heliothis virescens, trichoplusia ni, and culex quinqu ... | 1994 | 8161182 |
| hemolysin ii is more characteristic of bacillus thuringiensis than bacillus cereus. | to investigate the distribution of the hemolysin ii determinant among strains of bacillus cereus and bacillus thuringiensis, thirteen strains of b. cereus and fourteen strains of b. thuringiensis strains were tested for hybridization of their chromosomal dnas with a dna probe containing the b. cereus hemolysin ii gene. in addition, the production of hemolysin ii, whose activity is not inhibited by cholesterol, was tested. the presence (absence) of the hydridization response in the microorganisms ... | 1994 | 8161285 |
| a specific binding protein from tenebrio molitor for the insecticidal toxin of bacillus thuringiensis subsp. tenebrionis. | biopesticides based on the bacterium bacillus thuringiensis have attracted wide attention as safe alternatives to chemical insecticides. in this paper, we report, for the first time, the identification of a single binding protein from a coleopteran insect, tenebrio molitor, that is specific for the cryiii toxin of b. thuringiensis. the protein appeared as a single band of 144 kda on radioligand and immunoblots of total proteins extracted from brush border membrane vesicles of the midgut of t. mo ... | 1994 | 8166706 |
| influence of transcriptional and translational control sequences on the expression of foreign genes in caulobacter crescentus. | the influence of expression control sequences (ecss; promoters and ribosome-binding sites [rbss]), transcriptional terminators, and gene orientation on the expression of the escherichia coli lacz gene in the gram-negative microorganisms caulobacter crescentus and e. coli was investigated. a series of broad-host-range expression vectors, based on the rk2 plasmid derivative prk248, were constructed. the ecss included the tac promoter, the promoter for the surface layer protein of c. crescentus, an ... | 1994 | 8169208 |
| complete nucleotide sequence of the bacillus thuringiensis subsp. israelensis plasmid ptx14-3 and its correlation with biological properties. | the complete nucleotide sequence of the plasmid ptx14-3 from bacillus thuringiensis subsp. israelensis has been determined. the circular dna molecule was 7649 bp and had a g + c content of 35.1%. twenty-two open reading frames larger than 50 codons were identified. ten of these open reading frames are suggested to be protein coding regions. the existence of the polypeptides encoded by the mob14-3 and rep14-3 genes were verified by maxi-cells analysis in escherichia coli. even though the rep14-3 ... | 1994 | 8171127 |
| alkaline phosphodiesterase i release from eucaryotic plasma membranes by phosphatidylinositol-specific phospholipase c--iv. the release from cacia porcellus organs. | 1. alkaline phosphodiesterase i release from organs of cacia porcellus by the action of phosphatidylinositol-specific phospholipase c (piplc) of bacillus thuringiensis was studied. 2. a significant amount of alkaline phosphodiesterase i was released from both slices and homogenate of the kidney and small intestine but not from the liver or pancreas. 3. the release of the enzyme from kidney brush border membranes was dependent on, or proportional to, the reaction time and the piplc concentration. ... | 1994 | 8174751 |
| cellular toxicities and membrane binding characteristics of insecticidal crystal proteins from bacillus thuringiensis toward cultured insect cells. | the pattern of in vitro toxicity of activated toxins from several classes of entomocidal inclusion genes from bacillus thuringiensis was measured using eight established cell lines from lepidopteran insects. protoxins representing cryia(b), cryia(c), and a mixture of all three cryia toxins (subtypes a, b, and c; from b. thuringiensis subsp. kurstaki hd-1) were compared with the protoxin representing cryic in a bioassay which measured the viability of cultured insect cells upon exposure to entomo ... | 1994 | 8176242 |
| new serovars of bacillus thuringiensis: b. thuringiensis ser. coreanensis (serotype h25), b. thuringiensis ser. leesis (serotype h33), and b. thuringiensis ser. konkukian (serotype h34). | 1994 | 8176244 | |
| spores of bacillus thuringiensis serovar israelensis as tracers for ingestion rates by tetrahymena pyriformis. | 1994 | 8176245 | |
| [nucleotide sequence of the toxic domain of an insecticidal protein gene from b. thuringiensis subsp. kurstaki hd-1]. | two crystal protein genes, the 5.3kb and 6.6kb class respectively, from bacillus thuringiensis subsp. kurstaki hd-1 (b. t hd-1) had been cloned previously. based on the classification system of hofte and whiteley, these two genes should belong to cry i a (b) and cry i a (c) gene type respectively. the nucleotide sequence of the toxic domain of this cry i a (c) gene from b. t kurstaki hd-1 is firstly reported here and compared with that of cry i a (c) gene from b. t hd-73 and cry i a (b) gene fro ... | 1993 | 8178516 |
| flexibility in the protoxin composition of bacillus thuringiensis. | in at least three bacillus thuringiensis subspecies, multiple protoxin genes are confined to just a few of the many plasmids with two or more on one of > 100 mda and a particular gene, cryia(b), on a 40-50 mda plasmid. the latter is unstable but can be maintained in the population by cell mating. cells which had lost this plasmid compensated by increasing transcription of the remaining protoxin genes resulting in the formation of inclusions which differed from those in the parental strains in th ... | 1994 | 8181708 |
| reversal of resistance to bacillus thuringiensis in plutella xylostella. | continued success of the most widely used biopesticide, bacillus thuringiensis, is threatened by development of resistance in pests. experiments with plutella xylostella (diamondback moth), the first insect with field populations resistant to b. thuringiensis, revealed factors that promote reversal of resistance. in strains of p. xylostella with 25- to 2800-fold resistance to b. thuringiensis compared with unselected strains, reversal of resistance occurred when exposure to b. thuringiensis was ... | 1994 | 8183881 |
| [the effect of culex family mosquito larva on the sensitivity of anopheles mosquitos with various karyotypes to the entomopathogenic bacteria bacillus thuringiensis subsp. israelensis]. | culex (c. modestus) and anopheles (a. beklemishevi and a. messeae) larvae mosquito were treated with bacillus thuringiensis subsp. israelensis (bti) bacterium together and separately. it was determined that the presence of c. modestus reduced the mortality of anopheles larvae and altered the results of the selection of genotypes resistant to bti of the polymorphic species of a. messeae, c. modestus larvae consumed the pathogen more rapidly and protected the sensitive individuals of a. messeae wi ... | 1994 | 8188058 |
| characterization of larvicidal toxin protein from bacillus thuringiensis serovar japonensis strain buibui specific for scarabaeid beetles. | the delta-endo toxin proteins from bacillus thuringiensis which kill the larvae of various scarabaeid beetles such as anomala cuprea, a. rufocuprea and popillia japonica were purified by deae ion exchange chromatography. a protein with a molecular size of 130 kda was purified. during the purification a minor peak was also detected which was estimated to be 67 kda by sds-page. both 130 and 67 kda proteins showed larvicidal activity against a. cuprea. the lethal concentration of the 130 kda protei ... | 1994 | 8200856 |
| experimental study of subacute oral, dermal and inhalation toxicity of bulmoscide preparation. | the purpose of this study is to give the toxicological characteristics of subacute oral, dermal and inhalation exposure of microbial preparation bulmoscide, which is based on bacterium bacillus thuringiensis, serotype h-14. the study was performed on sexually mature wistar rats of both sexes. no significant changes in non-specific, clinico-laboratory and biochemical parameters as well as morphological examinations in any tested groups compared to the control groups were revealed. the doses 110 m ... | 1993 | 8219894 |
| cloning, expression, and mutagenesis of phosphatidylinositol-specific phospholipase c from staphylococcus aureus: a potential staphylococcal virulence factor. | staphylococcus aureus secretes a phosphatidylinositol (pi)-specific phospholipase c (pi-plc) which is able to hydrolyze the membrane lipid pi and membrane protein anchors containing glycosyl-pi. the gene for pi-plc (plc) was cloned from s. aureus into escherichia coli. oligonucleotide probes based on partial protein sequence and polyclonal antibodies raised against the purified protein were used to identify positive clones. e. coli transformed with a plasmid containing the plc gene expressed pi- ... | 1993 | 8225585 |
| expression of full-length and truncated forms of crystal protein genes from bacillus thuringiensis subsp. kurstaki in a baculovirus and pathogenicity of the recombinant viruses. | full-length and truncated forms of the crystal protein gene cryia(b) derived from bacillus thuringiensis subsp. kurstaki hd-1 and full-length cryia(c) gene of b. thuringiensis subsp. kurstaki hd-73 were introduced into the genome of the baculovirus autographa californica nuclear polyhedrosis virus, in place of the polyhedrin gene. all gene constructs were expressed at high levels in insect cells and insects upon infection with the recombinant viruses. the protein products were shown to be biolog ... | 1993 | 8228317 |
| protection from ultraviolet irradiation by melanin of mosquitocidal activity of bacillus thuringiensis var. israelensis. | a process for production, isolation, and purification of melanin produced by the fermentation of streptomyces lividans 66 harboring a recombinant plasmid pij702-bearing tyrosinase gene has been developed. the efficacy of melanin in the protection of mosquito larvacidal activity of bacillus thuringiensis var. israelensis against uv light has been studied. results obtained by the live cell counts and the bioassay of residual mosquitocidal activity of b. thuringiensis var. israelensis after exposur ... | 1993 | 8228318 |
| fine mapping and dna sequence of replication functions of bacillus thuringiensis plasmid ptx14-3. | ptx14-3 is a 7.5-kb cryptic plasmid isolated from a bacillus thuringiensis subspecies israelensis strain. like many other small plasmids in gram-positive bacteria, ptx14-3 replicates via a single-stranded dna intermediate. the nucleotide sequence of the replication region was determined and an open reading frame of 636 base pairs encoding a protein necessary for plasmid replication was identified by deletion analysis. no significant homology was found between this open reading frame and those en ... | 1993 | 8234484 |
| is231v and w from bacillus thuringiensis subsp. israelensis, two distant members of the is231 family of insertion sequences. | is231 constitutes a family of related insertion sequences (is) from bacillus thuringiensis. two new is231-related elements, is231v and is231w, have been isolated from the 72-mda plasmid of b. thuringiensis subsp. israelensis. these closely related 1964-bp is are delimited by 22-bp imperfect inverted repeats strongly similar to those of the other iso-is231. although the other known is231 harbor a single long open reading frame (orf), is231v and w display two slightly overlapping orf on the same d ... | 1993 | 8234486 |
| complete nucleotide sequence and identification of a putative promoter region for the expression in escherichia coli of the cryia(b) gene from bacillus thuringiensis var. aizawai hd133. | the sequence of a cry gene from bacillus thuringiensis var. aizawai hd133 was determined. this cry gene encodes a protein of 1155 amino acids, the molecular weight of which is 130622 da. when the nucleotide sequence of this cry gene was compared with the nucleotide sequence from b.t. var. aizawai ipl7 and var. berliner 1715, only five nucleotide changes were found. therefore, this cry gene should be grouped into the cryia(b) gene type. a 72 nucleotide sequence upstream of the open reading frame ... | 1993 | 8234543 |
| a study of five bacteriophages of the myoviridae family which replicate on different gram-positive bacteria. | a comparative study is reported on five phages of the myoviridae family which propagate on bacillus subtilis, b. thuringiensis, enterococcus sp., lactobacillus plantarum, or staphylococcus aureus. the phages are morphologically identical and characterized by isometric heads with conspicuous capsomers and by contractile tails with complex base plates. the phages show similar protein profiles, but vary considerably in burst size. phage dnas are about 95-166 kb in size and are unrelated by dna-dna ... | 1993 | 8240019 |
| structural characterization, membrane interaction, and specific assembly within phospholipid membranes of hydrophobic segments from bacillus thuringiensis var. israelensis cytolytic toxin. | the bacillus thuringiensis var. israelensis (bti) cytolytic toxin is hypothesized to exert its toxic activity via pore formation in the cell membrane as a result of the aggregation of several monomers. to gain insight into the toxin's mode of action, 2 putative hydrophobic 22 amino acid peptides were synthesized and characterized spectroscopically and functionally. one peptide corresponded to the putative amphiphilic alpha-helical region (amino acids 110-131, termed helix-2), and the other to am ... | 1993 | 8241124 |
| field trials of bacillus thuringiensis h-14 and bacillus sphaericus (strain 2362) formulations against anopheles arabiensis in the central highlands of madagascar. | malaria is highly endemic and unstable in the central highlands plateau of madagascar. the infection is seasonally transmitted by anopheles funestus and an. arabiensis. the latter species is abundant especially in rice-growing areas. the field efficacies of commercial formulations of bacillus thuringiensis h-14 and b. sphaericus (strain 2362) were assessed against an. arabiensis in 5 types of larval habitats. the granular formulation of b. thuringiensis (vectobac gr) provided very good control i ... | 1993 | 8245944 |
| use of cellular fatty acid analysis to characterize commercial brands of bacillus thuringiensis var. israelensis. | the cellular fatty acid composition of bacillus thuringiensis var. israelensis (b.t.i.) from 5 commercial brands (vectobac, acrobe, skeetal, bactimos and teknar), as well as of the current international standard for b.t.i. (ips 82), was determined using a hewlett-packard microbial identification system. the original strain of b.t.i., b.t. var. kurstaki, b.t. var. thuringiensis, b.t. var. morrisoni and bacillus sphaericus strain 2362 were used as outgroups. acrobe, bactimos, teknar, vectobac and ... | 1993 | 8245945 |
| field trial of two bacillus thuringiensis var. israelensis formulations for control of aedes species mosquitoes in michigan woodlands. | vectobac and bactimos corn cob granules were evaluated for control of aedes species mosquito larvae in woodland pools. no significant differences were seen between the 2 formulations. both provided greater than 90% control at application rates as low as 100 mg/m2 (0.89 lb/acre) and greater than 98% control at label-specified field application rates (2.5 or 5 lb/acre). | 1993 | 8245946 |
| immunological localization of bacillus thuringiensis serovar israelensis toxins in midgut cells of intoxicated anopheles gambiae larvae (diptera: culicidae). | fourth instar larvae of anopheles gambiae were intoxicated with doses of purified crystals from bacillus thuringiensis serovar israelensis (bti) corresponding to 50-fold the lc50 after 24 h. midguts were dissected after various contact times, then processed for immuno-light and -electron microscopy. immunodetection on thin sections was performed using affinity-purified rabbit igg against bti crystal cryivd or cyta polypeptides, in combination with anti-rabbit igg/peroxidase. both polypeptides we ... | 1993 | 8248622 |
| cholesterol oxidase: a potent insecticidal protein active against boll weevil larvae. | the discovery of proteins that control insects is critical for the continued growth of the agricultural biotechnology industry. a highly efficacious protein that killed boll weevil (anthonomus grandis grandis boheman) larvae was discovered in streptomyces culture filtrates. the protein was identified as cholesterol oxidase (e.c. 1.1.3.6). purified cholesterol oxidase was active against boll weevil larvae at a concentration (lc50 = 20.9 micrograms/ml) comparable to the bioactivity of bacillus thu ... | 1993 | 8250897 |
| [complete primary structure of bacillus thuringiensis extracellular ribonuclease]. | complete primary structure of an extracellular low molecular mass ribonuclease of bacillus thuringiensis was determined using edman degradation and mass-spectrometry analysis of individual peptides obtained after hydrolysis of the protein by cyanogen bromide and staphylococcal protease. the peptides were isolated and purified by hplc and denaturing page. the enzyme consists of 109 amino acid residues (asp 8, asn 6, thr 6, ser 10, glu 3, gln 1, pro 3, gly 9, ala 12, val 7, ile 7, leu 7, tyr 7, ph ... | 1993 | 8250978 |
| listeria monocytogenes phosphatidylinositol (pi)-specific phospholipase c has low activity on glycosyl-pi-anchored proteins. | the ability of the phosphatidylinositol-specific phospholipase c (pi-plc) from listeria monocytogenes to hydrolyze glycosyl phosphatidylinositol (gpi)-anchored membrane proteins was compared with the ability of the pi-plc from bacillus thuringiensis to hydrolyze such proteins. the l. monocytogenes enzyme produced no detectable release of acetylcholinesterase from bovine, sheep, and human erythrocytes. the cleavage of the gpi anchors of alkaline phosphatase from rat and rabbit kidney slices was l ... | 1993 | 8253689 |
| formation of melanin pigment by a mutant of bacillus thuringiensis h-14. | a mutant of bacillus thuringiensis h-14 produced a dark brown pigment during sporulation. production of the pigment depended on the nutritional properties of the growth medium. the pigment was identified as melanin, based on chemical tests and its infra-red spectrum. incorporation of l-tyrosine in the culture medium enhanced the level of melanin production, and l-3,4-dihydroxyphenylalanine (l-dopa) was detected in the culture broth during the late-exponential phase of growth. this indicates that ... | 1993 | 8254306 |
| rendering a membrane protein soluble in water: a common packing motif in bacterial protein toxins. | the recently determined structures of three different protein toxins by x-ray crystallography has unexpectedly revealed a common membrane-insertion domain. this domain consists of an alpha-helical bundle of between seven and ten helices, some of which are hydrophobic. the three toxins, colicin, insecticidal delta-endotoxin and diphtheria toxin are directed towards different hosts, have different killing mechanisms and bear no sequence homology. the observation of a common membrane-insertion doma ... | 1993 | 8256289 |
| primary structure of cryx**, the novel delta-endotoxin-related gene from bacillus thuringiensis spp. galleriae. | a cry-related sequence, designated cryx (embl x75019), was localized upstream of cryig, the delta-endotoxin gene cloned from spp. galleriae of bacillus thuringiensis and sequenced earlier [(1991) febs lett. 293, 25-28]. analysis of the cryx complete nucleotide sequence enabled us to explain its virtual crypticity and to reveal the chimeric structure of the genes, cryx and cryig. the amino acid sequence of 1,151 residues encoded by the continuous reading frame of cryx is similar to the other delt ... | 1993 | 8262221 |
| evidence for a glycolipid anchor of gp64, a putative cell-cell adhesion protein of polysphondylium pallidum. | the membrane-bound glycoprotein (gp64) of the cellular slime mold polysphondylium pallidum, is a putative cell-cell adhesion protein identified by adhesion-blocking antibody fragments. since gp64 can be purified in a few days and in substantial yields, it is a good candidate for clarifying the structure of a cell-cell adhesion protein. this study reveals that gp64 possesses a glycolipid anchor which is sensitive to deamination but resistant to phosphatidylinositol-specific phospholipase c from b ... | 1993 | 8269952 |
| hexadecylpalmitoylglycerol or ceramide is linked to similar glycophosphoinositol anchor-like structures in trypanosoma cruzi. | the lipopeptidophosphoglycan from trypanosoma cruzi is a glycosylated inositol-phosphoceramide isolated from epimastigotes at the stationary phase of growth (4-5 days). we have now purified two similar glycoinositolphospholipids (glycoinositolphospholipid a and glycoinositolphospholipid b) from epimastigotes after the second day of culture growth. [3h]palmitic acid was incorporated into 1-o-hexadecyl-2-o-palmitoylglycerol in glycoinositolphospholipid a and into ceramide in glycoinositolphospholi ... | 1993 | 8281945 |
| role of the cryivd polypeptide in the overall toxicity of bacillus thuringiensis subsp. israelensis. | the gene encoding the cryivd protein of b. thuringiensis subsp. israelensis crystals was disrupted by in vivo recombination. the toxicity of the cryivd protein-free inclusions was similar to that of the wild-type crystals on anopheles stephensi larvae but was half the wild-type toxicity on culex pipiens and aedes aegypti larvae. | 1993 | 8285695 |
| characterization of a bacillus thuringiensis strain which is toxic to the housefly musca domestica. | a bacillus thuringiensis isolate has been discovered which is toxic to the common housefly (musca domestica) as well as other diptera and lepidoptera. crystal delta-endotoxins purified from this isolate killed 50% of musca larvae at a concentration of 10.2 micrograms/ml, and beta-exotoxin was not detected. sodium dodecyl polyacrylamide gel electrophoresis of the purified crystals revealed three protein species which were related to cryia(b), cryib and cryiia toxins on the basis of immunoreactivi ... | 1993 | 8293955 |
| identification of a cryptic gene associated with an insertion sequence not previously identified in bacillus thuringiensis. | after screening several bt strains with a cryii toxin probe, clones from two strains were found to contain a cryptic cryiib gene associated with an insertion sequence element belonging to the is2/is3 family. the lack of expression of this gene appears to result from mutation of the upstream orf2 gene which has been shown to be necessary for cryii expression. | 1993 | 8293956 |
| identification of a promoter for the crystal protein-encoding gene cryivb from bacillus thuringiensis subsp. israelensis. | the cryivb gene of bacillus thuringiensis subsp. israelensis (bti) codes for a 135-kda insecticidal crystal protein, which is specifically toxic to dipteran larvae. we have identified a transcription start point (tsp) of cryivb by a primer extension experiment. the promoter sequence alignment, together with the chronology of appearance of the transcript, suggested that cryivb is transcribed by rna polymerase containing sigma 35 (e sigma 35). this was confirmed by investigation of cryivb transcri ... | 1993 | 8299955 |
| microheterogeneity in glycosylphosphatidylinositol anchor structures of bovine liver 5'-nucleotidase. | in our study, 5'-nucleotidase was released from bovine liver by the treatment with bacillus thuringiensis phosphatidylinositol-specific phospholipase c and purified to a homogeneous state by concanavalin a-sepharose and (diethylaminoethyl)-toyopearl column chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. purified 5'-nucleotidase were then cleaved by cyanogen bromide (cnbr), and then inositol phosphoglycan-containing c-terminal peptides (ipg peptides) were separated b ... | 1994 | 8305428 |
| is an amphiphilic region responsible for the haemolytic activity of bacillus thuringiensis toxin? | the amino acid sequence of the 27 kda protein responsible for the haemolytic activity of bacillus thuringiensis subsp. israelensis toxin has been analysed by secondary structure prediction, helical wheel/net diagrams and molecular mechanics calculations. we found that segment 116-126 presumably forms a strongly amphiphilic alpha-helix. this is supported by the findings that the synthesized segment 116-126 (a) has a significant alpha-helical content in water, and (b) displays an in vitro haemolyt ... | 1993 | 8307684 |
| an analysis of bacillus thuringiensis delta-endotoxin action on insect-midgut-membrane permeability using a light-scattering assay. | changes in the membrane permeability of manduca sexta midgut brush-border-membrane vesicles (bbmv) after addition of bacillus thuringiensis delta-endotoxins were studied using osmotic swelling experiments, volume changes being monitored as the change in 90 degrees light scattering. typically, control bbmv exhibited limited permeability for sucrose and salts (kcl), while being permeable for urea and glucose. the action of delta-endotoxin was examined using proteolytically activated cry-ia(c) and ... | 1993 | 8319686 |
| x chromosome variations of bacillus thuringiensis supernatant resistance and ribosomal dna content in drosophila melanogaster wild-type oregon r lines. | we have used the supernatant of bacillus thuringiensis cultures to follow variations of the ribosomal dna content in a wild-type oregon r line of drosophila melanogaster. these variations are revealed by differences in the degree of resistance to the lethal effect of the supernatant added in the culture medium. different x chromosomes, all originated from the same x chromosome, confer different degrees of resistance. increases and reductions in the number of the x ribosomal dna transcriptional u ... | 1993 | 8335478 |
| [the efficacy of entomopathogenic bacilli against ancylostomide larvae--nippostrongylus braziliensis travassons, 1914]. | effects of seven bioinsecticides, containing bacillus thuringiensis and b. sphaericus toxins, against n. braziliensis larvae were studied in vitro. bitoxibacillin, astur-3, astur-4, gomelin, lepidocide, dendrobacillin, thuringin and sphaerix were found highly effective larvicides. protein endotoxin was the principal component responsible for the larvicidal effect, the spores were of no importance. | 1993 | 8336643 |
| [the effect of water temperature on the action of bacterial insecticides against mosquito larvae]. | the ld50 logarithm of bacillus thuringiensis and b. sphaericus toxins effects on the larvae of aedes aegypti and culex pipiens is in inverse correlation with the water temperature. the influence of the temperature on the toxins effect on c. pipiens larvae is higher than that for a. aegypti larvae. similarly, b. sphaericus toxin effect depends on the water temperature to a greater measure than that of b. thuringiensis toxin. the authors predict a high efficacy of b. sphaericus-based insecticides ... | 1993 | 8336659 |
| purification and cdna cloning of bovine liver 5'-nucleotidase, a gpi-anchored protein, and its expression in cos cells. | a glycosylphosphatidylinositol (gpi)-anchored protein, 5'-nucleotidase [ec 3.1.3.5], was released from the membrane of bovine liver by use of phosphatidylinositol-specific phospholipase c (pi-plc) of bacillus thuringiensis and purified by several column chromatographies to a homogeneous state. the purified protein has an apparent molecular mass of 61 kda, as estimated by sds-polyacrylamide gel electrophoresis. from the partial amino acid sequence of a tryptic peptide, mixed oligonucleotides were ... | 1993 | 8340354 |
| a 20-kilodalton protein preserves cell viability and promotes cyta crystal formation during sporulation in bacillus thuringiensis. | the effect of a 20-kda protein on cell viability and cyta crystal production in its natural host, bacillus thuringiensis, was studied by expressing the cyta gene in the absence or presence of this protein. in the absence of the 20-kda protein, b. thuringiensis cells either were killed during sporulation (strain cryb) or produced very small cyta crystals (strain 4q7). expression of cyta in the presence of the 20-kda protein, however, preserved cell viability, especially in strain cryb, and in bot ... | 1993 | 8349568 |
| compatibility of cyclopoid copepods with mosquito insecticides. | larvivorous copepods (macrocyclops, mesocyclops and acanthocyclops) were tested for their sensitivities to commonly used mosquito larvicides and adulticides. the cyclopoids were not harmed by bacillus thuringiensis (h-14) (b.t.i.) or larviciding oil. control of mosquito larvae in field trials was accelerated by applying b.t.i. at the same time cyclopoids were introduced to a breeding site. among adulticides tested, the cyclopoids were least sensitive to permethrin. field trials demonstrated that ... | 1993 | 8350070 |
| investigations on possible resistance in aedes vexans field populations after a 10-year application of bacillus thuringiensis israelensis. | in the upper rhine valley (germany), bacillus thuringiensis var. israelensis has been widely used against floodwater mosquitoes over an area of approximately 500 km2 for more than 10 years. the susceptibility of larvae of aedes vexans field populations in 3 untreated (lake constance) and 3 treated areas (upper rhine valley) was assessed by means of bioassays with b.t.i. (bactimos wp, 6,000 aau/mg), following who guidelines. log-probit analyses and statistical evaluations of the data showed that ... | 1993 | 8350079 |
| purification and characterization of a trypsin-like digestive enzyme from spruce budworm (choristoneura fumiferana) responsible for the activation of delta-endotoxin from bacillus thuringiensis. | a trypsin-like enzyme purified from spruce budworm (choristoneura fumiferana) gut juice has a molecular mass of 25 kda and its ph activity profile indicates a pka of 8. sequence homology with bovine trypsin of the n-terminus and active site, and the ionization dependence for catalysis, reflect the typical trypsin-like activities measured. the action of this enzyme (designated cft-1) is compared to the neat gut juice with regard to the proteolytic activation of the delta-endotoxin from bacillus t ... | 1993 | 8353523 |
| insect-resistant chrysanthemum calluses by introduction of a bacillus thuringiensis crystal protein gene. | a 3'-end truncated crystal protein gene, derived from bacillus thuringiensis (bt) subsp. aizawai 7.21, encoding the toxic fragment of the insecticidal protein cryia(b), was constructed. the gene was inserted into a transformation vector, also carrying the neomycin phosphotransferase ii (nptii) gene and the beta-glucuronidase (gus) gene, and introduced in the oncogenic agrobacterium tumefaciens strain a281, harbouring the ti-plasmid ptibo542. the recombinant agrobacterium strain was used to trans ... | 1993 | 8353535 |
| [the role of bacillus thuringiensis in natural biocenoses]. | the results of the author's data and those from literature on ecology and genetic exchange of bacillus thuringiensis strains have been analyzed in this brief review. it has been concluded that there is no strict confinement of b. thuringiensis strains of the particular serotypes to certain habitat and that the bacteriocinogenicity is of great importance in the intraspecies competition and stability of strains in nature. it has been emphasized that the plasmid conjugation process in b. thuringien ... | 1993 | 8355625 |
| use of synthetic peptides to probe functional domains of a bacillus thuringiensis toxin. | two 10-residue peptides exhibiting sequence homology to cryia(a) toxin were chemically synthesized. one corresponds to a segment from residues 48-57 (peptide a) and is common to all cryia toxins and the second corresponds to a segment from residues 348-357 (peptide b) and is specific to the cryia(a) toxin. antibodies were raised in rabbits against both peptides. antipeptide a did not protect either bombyx mori or choristoneura fumiferana larvae against cryia(a) toxin. however, antipeptide b offe ... | 1993 | 8360514 |
| [creation of a hybrid protein gene based on bacillus thuringiensis delta endotoxins cryiiia and cria(a) and expression of its derivatives in escherichia coli]. | the 5'-terminal fragment (containing 1-565th codons) of bacillus thuringiensis var. tenebrionis gene for the coleoptera-specific delta-endotoxin cryiiia was cloned. this sequence was extended with either only a homologous fragment of cryia(a) or that one together with in-frame nptii or gus coding sequences. the obtained gene derivatives were expressed in e. coli. the analysis of hybrid polypeptides confirmed the enzymatic activities of bifunctional proteins and showed toxic properties of "insect ... | 1993 | 8361500 |
| [change in the permeability of liposome phospholipid membranes under the effect of bacillus thuringiensis delta-endotoxins]. | we studied release of the fluorescent calcein marker from egg-lecithin liposomes under action of intact delta-endotoxin from bacillus thuringiensis var. israilensis, and hydrolysed preparation of delta-endotoxin from bacillus thuringiensis var. kurstaki together with the motional parameters of 5- and 12-doxyl stearic radical probes in the liposomal membrane. the yield of the non-penetrating fluorescent marker was shown to be a sensitive indicator of the disturbance of the membrane barrier functi ... | 1993 | 8364069 |
| structural stability of bacillus thuringiensis delta-endotoxin homolog-scanning mutants determined by susceptibility to proteases. | forty homolog-scanning (double-reciprocal-crossover) mutant proteins of two bacillus thuringiensis delta-endotoxin genes (cryiaa and cryiac) were examined for potential structural alterations by a series of proteolytic assays. three groups of mutants could be identified. group 1, consisting of 13 mutants, showed no delta-endotoxin present during overexpression conditions in escherichia coli (48 h at 37 degrees c, with a ptac promoter). these mutants produced full-sized delta-endotoxin detectable ... | 1993 | 8368834 |