| structurally related bacillus thuringiensis delta-endotoxins display major differences in insecticidal activity in vivo and in vitro. | many strains within the 22 serotypes of bacillus thuringiensis produce crystal delta-endotoxins with slight differences in their insecticidal toxicity spectrum in vivo. since the basis of this specificity is unknown, we chose to compare the activity of delta-endotoxins from three strains: b. thuringiensis var. kurstaki hd-1, var. aizawai hd-249 and var. thuringiensis hd-350, both in vivo and on insect cell lines in vitro. immunoblotting with antisera to activated var. kurstaki p1 lepidopteran to ... | 1986 | 3027111 |
| binding and activity of bacillus thuringiensis delta-endotoxin to invertebrate cells. | fluorescein isothiocyanate was used as a label to detect delta-endotoxin of bacillus thuringiensis subsp. thuringiensis and israelensis in binding studies with different in vitro cell systems. protoxin of the subspecies thuringiensis could be labelled directly whereas the activated toxin had to be traced indirectly with labelled antibodies. both protoxin and activated toxin bound to primary midgut cell cultures of pieris brassicae larvae as well as to cells of an established culture of drosophil ... | 1986 | 3028295 |
| [cleavage of dna from 2 phages of bacillus thuringiensis by ecori and hindiii endonucleases]. | the dna of two bacillus thuringiensis phages was restricted by endonucleases ecori and hindiii and the electrophoretic distribution of the fragments in agarose gel was studied. ecori was shown to restrict the dna of phage 1-97a into 8 fragments and the dna of phage 1-97b into 12 fragments. restriction with hindiii results in the formation of 22 and 9 fragments for phage 1-97a and phage 1-97b, respectively. the molecular mass of the dnas determined by summing up ecori restricts is 80.87 mda for p ... | 1986 | 3029552 |
| alkaline phosphodiesterase i release from eucaryotic plasma membranes by phosphatidylinositol-specific phospholipase c. ii. the release from brush border membranes of porcine intestine. | ectoenzyme release from porcine intestinal brush border membranes by phosphatidylinositol-specific phospholipase c of bacillus thuringiensis was studied. alkaline phosphodiesterase i, alkaline phosphatase and 5'-nucleotidase were released from both slices and brush border membranes. the pattern of alkaline phosphodiesterase i release was the same as that of alkaline phosphatase. the release of alkaline phosphodiesterase i induced by phospholipase c was dependent on, or proportional to, the react ... | 1986 | 3029900 |
| [biochemical manifestations of the poisoning of larvae of aedes aegypti (insecta, diptera) by the delta-endotoxin of bacillus thuringiensis israelensis. i. hemolymph carbohydrates]. | the glycemia of 4th instar larvae of aedes aegypti (diptera culicidae) was determined over a 30 min to 36 hrs period following their immersion in water containing 0.00-0.01-0.02-0.1-1.0 mg per liter of a 12,000 i. u. per mg preparation of the delta-endotoxin of bacillus thuringiensis israelensis. seven major carbohydrate fractions were separated in the haemolymph, among which glycogen, trehalose and glucose were identified; the most concentrated of the 4 remaining unknown fractions, exhibits a s ... | 1986 | 3030517 |
| characterization of the genes encoding the haemolytic toxin and the mosquitocidal delta-endotoxin of bacillus thuringiensis israelensis. | the crystalline parasporal inclusions (crystals) of bacillus thuringiensis israelensis (bti), which are specifically toxic to mosquito and black fly larvae, contain three main polypeptides of 28 kda, 68 kda and 130 kda. the genes encoding the 28 kda protein and the 130 kda protein have been cloned from a large plasmid of bti. escherichia-coli recombinant clones containing the 130 kda protein gene were highly active against larvae of aedes aegypti and culex pipiens, while b. subtilis recombinant ... | 1986 | 3031426 |
| [biological control of culicidae and simuliidae: bacterial insecticides]. | | 1985 | 3031748 |
| is50l as a non-self transposable vector used to integrate the bacillus thuringiensis delta-endotoxin gene into the chromosome of root-colonizing pseudomonads. | insertion sequence is50l of transposon tn5 was used as a non-self transposable vector to integrate the delta-endotoxin gene (tox) from bacillus thuringiensis subsp. kurstaki hd-1 into the chromosome of two corn-root colonizing strains of pseudomonas fluorescens (112-12 and ps3732-3-7). a dna fragment containing the kmr gene from tn5 and tox was inserted into an is50l element (is50l-tox) contained on a suicide plasmid. transposition of is50l-tox into the chromosome of p. fluorescens 112-12 and ps ... | 1987 | 3036648 |
| cloning and nucleotide sequence of different iso-is231 elements and their structural association with the tn4430 transposon in bacillus thuringiensis. | a family of five repetitive sequences (rs) has been isolated from a plasmid dna library of bacillus thuringiensis strain berliner 1715. in a previous paper [mahillon et al., embo j. 4(1985)3895-3899] one of these was shown to harbor all the features of an is element (is231). further nucleotide sequence analysis revealed that two other rs, flanking the delta-endotoxin gene, are actually variants of is231. comparison of the nucleotide sequences surrounding the iso-is231 elements showed a unique st ... | 1987 | 3036650 |
| cloning and heterologous expression of an insecticidal delta-endotoxin gene from bacillus thuringiensis var. aizawai ic1 toxic to both lepidoptera and diptera. | bacillus thuringiensis var. aizawai ic1 synthesises an insecticidal protein delta-endotoxin (130-135 kda) that is toxic to both lepidopteran and dipteran larvae, and cross-reacts immunologically with certain monospecific lepidopteran toxins. a 166-kb plasmid from this bacterium was found to hybridise with an intragenic probe derived from the clone b. thuringiensis var. sotto lepidopteran-specific delta-endotoxin gene. a strongly hybridising 5.2-kb ssti fragment from var. aizawai plasmid dna was ... | 1987 | 3038691 |
| effects of phospholipases c from bacteria on binding of enkephalin to rat brain membranes. | the effects of phospholipases c on the equilibrium constants and maximal binding capacities of tritiated [d-ala2,-d-leu5] enkephalin to rat brain membranes were investigated using phosphatidylcholine-hydrolyzing phospholipase c and sphingomyelinase c of bacillus cereus and, phosphatidylinositol-specific phospholipase c of bacillus thuringiensis. when 72% of the phosphatidylinositol in the rat brain membranes was hydrolyzed by phosphatidylinositol-specific phospholipase c, the affinity of opiate ... | 1987 | 3039692 |
| expression of a cloned bacillus thuringiensis crystal protein gene in escherichia coli. | the expression in escherichia coli of a cloned crystal protein gene from bacillus thuringiensis was investigated through the use of fusions of the crystal protein gene promoter to beta-galactosidase and catechol oxidase genes. analysis of deletion and insertion derivatives of the crystal protein gene promoter showed that a region of b. thuringiensis dna located between 87 and 258 base pairs upstream from the transcription initiation site caused reduced transcription from this promoter. insertion ... | 1987 | 3040677 |
| [restriction mapping of e. coli-cloned fragments of the plasmid dna of bacillus thuringiensis subsp. israelensis]. | | 1988 | 3073647 |
| identification of a positive retroregulator that stabilizes mrnas in bacteria. | a positive retroregulator that enhances the expression of an upstream gene(s) has been identified. it resides within a 381-base pair (bp) restriction fragment containing the transcriptional terminator of the crystal protein (cry) gene from bacillus thuringiensis vs. kurstaki hd-1. this fragment was fused to the distal ends of either the penicillinase (penp) gene of bacillus licheniformis or the interleukin 2 cdna from the human jurkat cell line. in both cases, the half-lives of the mrnas derived ... | 1986 | 3085085 |
| plasmids associated with a phagelike particle and with a satellite inclusion in bacillus thuringiensis ssp. israelensis. | variants of bacillus thuringiensis ssp. israelensis were isolated using a 42 degrees c plasmid curing method. those that were missing the large toxic crystalline inclusion still possessed in their sporulated cells a small inclusion similar to the satellite inclusion of the wild type. these crystal-minus but satellite-positive variants, like the wild type, produced sporulation-dependent phagelike particles; variants lacking both the crystal and the satellite did not. these latter strains lacked b ... | 1986 | 3087608 |
| induced release of bacillus spores from sporangia by sodium sulphate. | incubation of sporulating cultures of bacillus anthracis, b. cereus, b. subtilis and b. thuringiensis in 1.0 mol/l sodium sulphate markedly increased the release of free spores from sporangia. it is postulated that the release of spores is due to activation of latent autolysins which hydrolyse sporangial cell walls. sodium sulphate-induced lysis of sporangia represents a novel and highly effective method for the recovery of spores from cultures of bacillus species. | 1986 | 3087932 |
| effects of bacillus thuringiensis and insect pathogen, pseudomonas aeruginosa, on mammalian gastrointestinal tract. | | 1986 | 3089926 |
| [changes in the electrical characteristics of bacterial cells in the disruption of the barrier function of the cytoplasmic membrane]. | a change in the electro-orientation spectrum followed by a change in the electric characteristics of bacterial cells had been measured when the barrier function of the cytoplasmic membrane was disordered under the action of damaging physical and chemical factors. analysis of changes in the spectra at a frequency of 10(4) to 10(7) hz allows one to estimate the degree of cell damage in quantitative terms. the paper presents the results of comparing three procedures for such an estimation: inoculat ... | 1986 | 3102904 |
| microbes in or near field-testing. | | 1987 | 3114880 |
| identification of self-transmissible plasmids in four bacillus thuringiensis subspecies. | the transfer of plasmids by mating from four bacillus thuringiensis subspecies to bacillus anthracis and bacillus cereus recipients was monitored by selecting transcipients which acquired plasmid pbc16 (tcr). transcipients also inherited a specific large plasmid from each b. thuringiensis donor at a high frequency along with a random array of smaller plasmids. the large plasmids (ca. 50 to 120 megadaltons), pxo13, pxo14, pxo15, and pxo16, originating from b. thuringiensis subsp. morrisoni, b. th ... | 1987 | 3117773 |
| amino acid sequence and entomocidal activity of the p2 crystal protein. an insect toxin from bacillus thuringiensis var. kurstaki. | the gene encoding the 66-kda entomocidal protein (p2 protein or mosquito factor) from bacillus thuringiensis var. kurstaki has been isolated by the use of a 62-mer oligonucleotide probe that encoded 21 amino acids of the p2 protein nh2 terminus. the dna sequence of the gene, designated crybi, was unique from the published sequences of other b. thuringiensis genes. however, the amino acid sequence of the p2 protein, as deduced from the dna sequence of the crybi gene, was found to contain a sequen ... | 1988 | 3121615 |
| construction of a bifunctional genetically labelled plasmid for bacillus thuringiensis subsp. israelensis. | a small cryptic plasmid of bacillus thuringiensis subsp. israelensis was labelled in vitro with two genetic markers. one of the recombinant plasmids was mapped and transformed in escherichia coli, bacillus subtilis and bacillus thuringiensis. this and similar shuttle plasmids could be very useful as vectors for the investigation of the toxin genes in their own host. | 1988 | 3144956 |
| isolation and characterization of eg2158, a new strain of bacillus thuringiensis toxic to coleopteran larvae, and nucleotide sequence of the toxin gene. | a novel strain of bacillus thuringiensis was isolated from soybean grain dust from kansas and found to be toxic to larvae of leptinotarsa decemlineata (colorado potato beetle). the strain (eg2158) synthesized two parasporal crystals: a rhomboid crystal composed of a 73116 dalton protein of approximately 30 kda. plasmid transfer and gene cloning experiments demonstrated that the 73 kda protein was encoded on an 88 mda plasmid and that the protein was toxic to the larvae of colorado potato beetle ... | 1988 | 3146015 |
| comparison between the molecular characteristics and the potential activity of x and y nucleolar organizers from various drosophila melanogaster laboratory lines. | the molecular characteristics of nucleolar organizers from x and y chromosomes of different drosophila melanogaster lines have previously been studied (17). by analysis of appropriate genetic crosses we show in the present study that the x and y chromosomes of these lines can confer different degrees of resistance on an inhibitor of ribosomal rna synthesis (beta exotoxin or thuringiensin) present in the thermostable supernatant of bacillus thuringiensis cultures. none of the lines studied gives ... | 1988 | 3147116 |
| [the expression of a new bifunctional vector for cloning in bacillus thuringiensis subsp. israelensis and its deletion variants]. | | 1988 | 3150250 |
| bacillus larval toxin crystal protein. | during sporulation some bacteria produce parasporal inclusions which are toxic for insect larvae. the proteins responsible for this toxicity have been characterized and their genes have been cloned. using genetic engineering methods, it is now possible to establish new bacterial strains and to introduce these genes into plant genomes. | 1987 | 3153619 |
| indigenous bulk production of bacillus thuringiensis israelensis (serotype h-14) & its larvicidal action against anopheles stephensi. | | 1988 | 3169900 |
| the utilization of bacilli as larvicidal agents against anopheline and culicine mosquitoes in turkey. i. larvicidal activity of bacillus thuringiensis serotype h-14. | standard ips-82 and a wettable powder (bactimos) of bacillus thuringiensis (h-14) were tested against local mosquito species, cx. pipiens and an. sacharovi, in the laboratory in turkey. the dose-mortality regression lines for both organisms had similar slopes with each formulation. bactimos was less effective against both organisms, especially at higher concentrations (lc95/lc50 5.78 vs 1.95). | 1988 | 3184242 |
| isolation of a hemolysin from a spore-crystal mixture of bacillus thuringiensis israelensis (serotype h-14). | a hemolytic toxin from bacillus thuringiensis israelensis was obtained by alkaline extraction and fast protein liquid chromatography (chromatofocusing followed by gel filtration). the toxin displayed a pi of 4.6-4.8 and an mr of 26,000. amino acid analysis demonstrated large amounts of serine, glycine and glutamic acid. the toxin was strongly lytic for rabbit, human and non-human primate erythrocytes, and was weakly lytic toward equine, feline, canine, bovine, amphibian and reptilian erythrocyte ... | 1988 | 3188063 |
| host range and selected factors influencing the mosquito larvicidal activity of the pg-14 isolate of bacillus thuringiensis var. morrisoni. | laboratory bioassay of the pg-14 isolate of bacillus thuringiensis var. morrisoni (serotype 8a:8b) against early fourth instar larvae of 8 species of mosquitoes revealed a range of susceptibilities similar to the susceptibilities of these species to bacillus thuringiensis var. israelensis (serotype 14). the most susceptible species were: culex quinquefasciatus, cx. salinarius, anopheles albimanus and aedes aegypti. the least susceptible species tested was an. quadrimaculatus. separate bioassays ... | 1988 | 3193097 |
| laboratory study of the influence of water temperature and ph on bacillus thuringiensis var. israelensis efficacy against black fly larvae (diptera: simuliidae). | an experimental formulation of bacillus thuringiensis var. israelensis was used in the laboratory to assess the influence of water temperature and ph on the relationship between concentration, duration of exposure, and mortality of the northern black fly species simulium decorum and prosimulium mixtum/fuscum group. mortality increases in both species with increases in duration of exposure, concentration, temperature and ph. onset of death is shortened by increase in concentration and temperature ... | 1988 | 3193100 |
| method for determining settling rates of bacillus thuringiensis serotype h-14 formulations. | a water-column apparatus is described in which settling rates of bacillus thuringiensis serotype h-14 [b.t. (h-14)] formulations can be indirectly quantified using mortality of mosquito larvae at restricted depths as an index of b.t. (h-14) activity. to illustrate the type of data provided by this method, commercial b.t. (h-14) products (bactimos, teknar, vectobac) and experimental formulations were compared at the manufacturers' recommended rates for mosquito control. all evaluations utilized l ... | 1988 | 3193109 |
| laboratory evaluation of formulations of bacillus thuringiensis var. israelensis combined with methoprene or a monomolecular surface film against anopheles albimanus and an. stephensi. | | 1988 | 3193121 |
| sequence of the bacillus thuringiensis phosphatidylinositol specific phospholipase c. | | 1988 | 3194218 |
| the initial stages in the action of an insecticidal delta-endotoxin of bacillus thuringiensis var. israelensis on the epithelial cells of the malpighian tubules of the insect, rhodnius prolixus. | the effects of the 27 x 10(3) mr insecticidal delta-endotoxin from bacillus thuringiensis var. israelensis have been studied using, as a model system, isolated insect malpighian tubules. at all concentrations of the toxin higher than 1 microgram ml-1 (4 x 10(-8) moll-1) applied to the outer surface of the tubules, fluid secretion failed within about 30 min. except at very high concentrations, where failure always takes at least 30 s, there was an inverse relationship between the concentration of ... | 1988 | 3198707 |
| feeding behavior of aedes aegypti larvae and toxicity of dispersed and of naturally encapsulated bacillus thuringiensis var. israelensis. | | 1988 | 3198932 |
| efficacy of two formulations of bacillus thuringiensis var. israelensis (h-14) against aedes vexans and safety to non-target macroinvertebrates. | an experimental sandoz formulation of bacillus thuringiensis var. israelensis (san 402 sc 98) was several times more effective than abbott abg 6188 against larvae of aedes aegypti and ae. vexans in the laboratory. field applications of san 402 sc 98 at 0.25 liter/ha and abg 6188 at 1.00 liter/ha resulted in more than 97% control of ae. vexans larvae after 48 hours, with residual activity of 24 hours or less. the amphipod, hyallela azteca, and 4 species of water beetles were apparently unaffected ... | 1988 | 3199115 |
| nucleotide sequence of a bacillus thuringiensis aizawai ic1 entomocidal crystal protein gene. | | 1988 | 3205732 |
| age related occurrence of natural agglutinins in the erisilkworm, philosamia ricini. | natural agglutinins against human, guinea pig, and rat erythrocytes (rbc) and bacteria bacillus thuringiensis were readily detected in hemolymph of final instar larvae with resulting titers of 0-9 (log2). titers were independent of sex and season but varied conspicuously and reproducibly with age. moreover, response of hemagglutinins to heating varied with age being heat-labile in younger larvae, yet totally resistant to heating for 30 min at 70 degrees c in older ones. bacterial agglutinins wer ... | 1988 | 3208956 |
| complete nucleotide sequence of pgi2, a bacillus thuringiensis plasmid containing tn4430. | | 1988 | 3211758 |
| toxic and morphological effects of bacillus thuringiensis preparations on larval stages of the oriental rat flea (siphonaptera: pulicidae). | | 1988 | 3216067 |
| five unique temperate phages from a polylysogenic strain of bacillus thuringiensis subsp. aizawai. | five temperate phages were isolated from strain 4042b of bacillus thuringiensis subsp. aizawai. the phages, which were heteroimmune, could also be distinguished by their host ranges, plaque and particle morphologies, serological specificities, and locations of restriction endonuclease cleavage sites on their chromosomes. besides maintaining a stable lysogenic relationship with the 4042b host strain, each phage formed a stable lysogen with bacillus cereus. | 1988 | 3221199 |
| kinetics of hemolysis induced by a toxin from bacillus thuringiensis israelensis. | the kinetics of hemolysis resulting from the action on rabbit erythrocytes of a highly purified cytolytic toxin (26,000 mol. wt) isolated from a spore-crystal mixture of bacillus thuringiensis israelensis was studied. course of hemolysis, as determined by release of hemoglobin, yielded sigmoid curves whose maximum slopes were taken as a measure of the rate of lysis. hemolysis occurred without an induction period, and the rate of lysis was a linear function of toxin concentration. rate of hemolys ... | 1988 | 3238702 |
| [inactivation of the thermostabile exotoxin of bacillus thuringiensis by soil microorganisms]. | | 1988 | 3243461 |
| [hygienic problems of protecting the environment in relation to the production and use of microbiological products for plant protection]. | | 1988 | 3243476 |
| [toxic effects of bacillus thuringiensis var. kurstaki to the immature stage of aedes aegypti]. | | 1988 | 3244164 |
| potentiation of the cytotoxic activity of anti-cancer drugs against cultured l1210 cells by bacillus thuringiensis subsp. israelensis toxin. | | 1988 | 3246017 |
| [a new subspecies of bacillus thuringiensis]. | | 1988 | 3247716 |
| [an integrated method of using biological and chemical insecticides for controlling flies]. | | 1988 | 3249575 |
| [effect of preparations of bacillus thuringiensis serotype h-14 on warm-blooded animals]. | | 1988 | 3249594 |
| [growth and spore formation in bacillus thuringiensis at high substrate concentrations]. | the work was aimed at studying the effect exerted by elevated concentrations of glucose, yeast extract and acetate on the growth of bacillus thuringiensis subsp. galleriae, strain 69-6, and on the formation of spores and crystals by it. glucose concentrations from 30 to 100 g per litre did not prevent spore formation. yeast extract inhibited spore formation to a greater extent and stopped it almost completely at a concentration of 20 g per litre. acetate at a concentration of 1.0 to 10 g per lit ... | 1988 | 3249598 |
| field tests of bacillus thuringiensis var. israelensis against culex mosquito larvae in dhaka city. | | 1988 | 3250457 |
| [variability of bacillus thuringiensis bacteriophages with c2-morphology]. | biological as well as physicochemical properties of bacillus thuringiensis bacteriophages "17" and "7/13" having c2-morphology and isolated from factory phagolysates were studied. the bacteriophages are identical in the lytic spectrum++, morphology, size, gc-content, have the same buoyant density. the physical map for restriction endonucleases ecori, hindiii, salgi and mvai has been constructed of the bacteriophages dna. heteroduplex analysis has revealed the nonhomologous region of the deletion ... | 1988 | 3251143 |
| comparative toxicity of bacillus thuringiensis var. israelensis crystal proteins in vivo and in vitro. | bacillus thuringiensis var. israelensis crystal proteins were purified by fplc on a mono q column to yield 130, 65, 28, 53, 30-35 and 25 kda proteins. all the purified proteins killed aedes aegypti larvae after citrate precipitation, but the 65 kda protein was the most toxic. a precipitated mixture of 27 and 130 kda proteins was almost as toxic as solubilized crystals. in assays against a range of insect cell lines, the activated form (25 kda) of the 27 kda protein was generally cytotoxic with t ... | 1988 | 3254944 |
| alteration of trichostrongylus colubriformis egg permeability by bacillus thuringiensis israelensis toxin. | a toxin from the bacterium bacillus thuringiensis israelensis is lethal to nematode eggs. exposure of eggs of the ruminant nematode trichostrongylus colubriformis to the toxin significantly increased the eggs' permeability to radiolabeled phenylalanine within 2 hr. calcium chloride inhibited the toxin-induced change in egg permeability. iodine staining of eggs that were exposed to the microbial toxin revealed that egg permeability was altered within 5 min and was dependent on the dose of toxin. ... | 1987 | 3295166 |
| nucleotide sequence of the insecticidal protein gene of bacillus thuringiensis strain aizawai ipl7 and its high-level expression in escherichia coli. | a dna fragment carrying the insecticidal protein gene of bacillus thuringiensis subsp. aizawai ipl7 was cloned from a 78-kb plasmid. the nucleotide sequence revealed that the cloned dna fragment contained a 3465-bp protein-coding region with 156-bp 5'-flanking, and 168-bp 3'-flanking regions. the open reading frame encoded a 130,690 da protein consisting of 1155 amino acid residues. nucleotide sequence comparison of the aizawai gene with the published berliner 1715 gene showed only 8 nt changes ... | 1987 | 3297927 |
| a highly sensitive bacterial assay for toxins based on swarming inhibition, and comparison with the cup plate assay based on growth inhibition. | the motility inhibition of the swarming bacteria proteus mirabilis and azospirillum brasilense was found to be an appropriate parameter to indicate toxic effects caused by some mycotoxins, lactones and anhydrides of dicarboxylic acids. if these substances are in contact with the motile bacteria the following phenomena can be observed: at a certain toxin concentration the swarming of the bacteria is inhibited. if the concentration is increased the swarming ceases, and at still higher concentratio ... | 1987 | 3299877 |
| cytolytic activity and immunological similarity of the bacillus thuringiensis subsp. israelensis and bacillus thuringiensis subsp. morrisoni isolate pg-14 toxins. | the parasporal bodies of the mosquitocidal isolates of bacillus thuringiensis subsp. israelensis and b. thuringiensis subsp. morrisoni isolate pg-14 were compared with regard to their hemolytic and cytolytic activities and the immunological relatedness of the 28- and 65-kilodalton (kda) proteins that occur in both subspecies. the alkali-solubilized parasporal bodies of b. thuringiensis subsp. israelensis caused 50% lysis of human erythrocytes at 1.14 micrograms/ml, whereas those of b. thuringien ... | 1987 | 3300548 |
| cloning and expression in escherichia coli of an insecticidal crystal protein gene from bacillus thuringiensis var. aizawai hd-133. | using a gene probe derived from the cloned var. sotto insecticidal crystal protein (icp) gene, we have cloned a bacillus thuringiensis var. aizawai hd-133 icp gene in escherichia coli. the gene encodes a polypeptide that is toxic to lepidoptera in vivo and in vitro. the protein is expressed at a level sufficient to produce phase-bright inclusions in recombinant e. coli strains, and these inclusions can be partially purified using discontinuous sucrose density gradients. immunoblotting shows that ... | 1987 | 3329679 |
| characterization of the toxicity and cytopathic specificity of a cloned bacillus thuringiensis crystal protein using insect cell culture. | an insecticidal protein gene from bacillus thuringiensis var. aizawai was cloned in escherichia coli. the cloned gene expressed at a high level and the synthesized protein appeared as an insoluble, phase-bright inclusion in the cytoplasm. these inclusions were isolated by density gradient centrifugation, the isolated protein was activated in vitro by different proteolytic regimes and the toxicity of the resulting preparations was studied using insect cells grown in tissue culture. the inclusions ... | 1987 | 3330756 |
| u.v.-induced and n-methyl-n'-nitro-n-nitrosoguanidine-induced mutagenesis in bacillus thuringiensis. | the lethal and mutagenic effects of u.v. light and n-methyl-n'-nitro-n-nitrosoguanidine (mnng) on bacillus thuringiensis were investigated. lethality studies demonstrated that b. thuringiensis was relatively sensitive to these agents. this bacterium was mutated at the rifampicin resistance marker by u.v. light and to a lesser extent by the direct acting alkylating agent mnng. one mutant selected for its greater sensitivity to u.v. light expressed a higher frequency of mutagenesis after u.v. ligh ... | 1987 | 3331699 |
| the biotechnology of bacillus thuringiensis. | one of the challenges in the application of biotechnology to pest control is the identification of agents found in nature which can be used effectively. biotechnology offers the potential of developing pesticides based on such agents which will provide environmentally sound and economically feasible insect control alternatives. such an agent, the insect pathogen bacillus thuringiensis, is the subject of intense investigations in several laboratories. insecticides which use the entomocidal proper ... | 1987 | 3333741 |
| nucleotide sequence of an additional crystal protein gene cloned from bacillus thuringiensis subsp. thuringiensis. | | 1988 | 3362680 |
| [effect of the conditions for mosquito larval development on their sensitivity to bacterial insecticides]. | | 1988 | 3367856 |
| isolation of a bacillus thuringiensis rna polymerase capable of transcribing crystal protein genes. | we report the isolation of an rna polymerase from sporulating cells of bacillus thuringiensis subsp. kurstaki hd-1-dipel that directs transcription from the promoter region of an insecticidal crystal protein gene. the core components of this rna polymerase are associated with a polypeptide that has an apparent mass of 35 kda. neither rna polymerase holoenzyme isolated from vegetative b. thuringiensis, nor the core derived from this enzyme, is capable of transcribing from the crystal protein gene ... | 1988 | 3380786 |
| [screening of temperature-sensitive mutants of bacillus thuringiensis phages and the identification of its character]. | | 1988 | 3388831 |
| [extracellular ribonuclease from bacillus thuringiensis]. | the ability of the strain bacillus thuringiensis var. subtoxicus to produce extracellular ribonuclease (ribonuclease bt) was studied. it was found that the culture medium possesses a rna-depolymerizing activity whose maximum is observed 4-5 hours after the beginning of the linear growth phase. a three-step chromatography of the culture extract on phosphocellulose resulted in a homogeneous enzyme with a molecular mass of 12000 da. the enzyme showed the maximum activity towards rna at ph 8.5, cata ... | 1988 | 3395642 |
| nucleotide sequence of crystal protein gene isolated from b. thuringiensis subspecies entomocidus 60.5 coding for a toxin highly active against spodoptera species. | | 1988 | 3399402 |
| crystallization and preliminary x-ray diffraction studies of a toxic crystal protein from a subspecies of bacillus thuringiensis. | the toxic crystal protein (mr 64,000) from a subspecies of the bacterium bacillus thuringiensis has been solubilized and recrystallized yielding diffraction quality crystals. crystals are obtained by a change in ph and ionic strength using na2co3. they can also be obtained by a change in ionic strength only using nabr as the precipitant. the space group of both forms is c222(1) with a = 133, b = 116, c = 104 a and one molecule/asymmetric unit. still photographs show reflections to 3.0-a resoluti ... | 1988 | 3403554 |
| [biological activity of the parasporal crystals of bacillus thuringiensis]. | | 1988 | 3411010 |
| factors affecting the larvicidal activity of bacillus thuringiensis israelensis toxin for trichostrongylus colubriformis (nematoda). | | 1988 | 3418132 |
| affinity purification of a 65-kilodalton parasporal protein from bacillus thuringiensis pg-14 that shows mosquitocidal activity. | by using antibody-mediated affinity chromatography, a highly mosquito larvicidal but nonhemolytic fraction was obtained from alkali-solubilized, silkworm (bombyx mori) larval gut juice-treated parasporal inclusions of bacillus thuringiensis strain pg-14 (serotype 8a:8b). this fraction contained a 65-kda protein only but not a 25-kda protein, the main component in the flow through fraction unbound to the affinity column. the 25-kda protein purified from the unbound fraction by cm-cellulose chroma ... | 1988 | 3421669 |
| insecticidal activity of bacillus thuringiensis subspecies against menopon gallinae (mallophaga: menoponidae). | 10 bacillus thuringiensis strains were used to determine the susceptibility of menopon gallinae (l). in order to identify b. thuringiensis from dead insects, previously exposed to bacteria, the streptomycin-resistant mutants of strains were also applied. the experiments were conducted in a group of 20 specimens, in three replications. the absorbtion at 750 nm directly corresponded to the concentration of 23 x 10(6) spores/ml in each assay. the biting lice were exposed on agar plates, inoculated ... | 1987 | 3425965 |
| influence of surfactants and polymeric adjuvants on physicochemical properties, droplet size spectra and deposition of fenitrothion and bacillus thuringiensis formulations under laboratory conditions. | the effect of two surfactants and two polymeric adjuvants on droplet size spectra and deposition patterns of nine spray formulations was investigated following atomization in a laboratory chamber using a spinning disc atomizer that can produce a narrow droplet size spectrum. spray droplets were sampled using kromekote cards and deposit recoveries were examined on glass plates. physicochemical properties studied were: viscosity-shear rate relationship, surface tension, volatility, ph, conductance ... | 1987 | 3429786 |
| properties of bovine erythrocyte acetylcholinesterase solubilized by phosphatidylinositol-specific phospholipase c1. | the properties of acetylcholinesterase solubilized from bovine erythrocyte membrane by phosphatidylinositol (pi)-specific phospholipase c of bacillus thuringiensis or with a detergent, lubrol-px, were studied. the activity of lubrol-px-solubilized acetylcholinesterase was broadly distributed in the fractions having ve/vo = 1.0-2.0 in gel filtration on a sepharose 6b column. the intermediary fractions (ve/vo = 1.3-1.7) were collected as "the middle active sepharose 6b eluate" and characterized on ... | 1987 | 3436952 |
| [spontaneous bacteriophage induction in bacillus thuringiensis]. | the production of temperate bacteriophages was studied in the process of batch cultivation of three bacillus thuringiensis lysogenic strains. phage titres were determined using an indicator culture (ipm-1148). the growth of bacteriophages was induced when thermoactivated spores germinated. some cells (1.10(-3)-2.10(-3)) underwent lysis without their division. the subsequent lytic cycles occurred in the actively growing culture. phage titres ceased to rise before the exponential growth phase was ... | 1987 | 3448468 |
| [laboratory studies of the effectiveness of the polish biological preparation turidan in the control of flies (musca domestica l.) sensitive to insecticides]. | | 1987 | 3451359 |
| dynamics of biomass production, sporulation & toxin synthesis in bacillus thuringiensis h 14 strains. | | 1987 | 3451904 |
| comparative cost of mosquito control with larvicidal bacilli and insecticides. | | 1987 | 3452548 |
| plasmids and crystal toxin production in bacillus thuringiensis subsp. israelensis. | | 1986 | 3471064 |
| laboratory and field efficacy of bacillus thuringiensis var. israelensis and bacillus sphaericus against anopheles gambiae s.l. and culex quinquefasciatus in ouagadougou, burkina faso. | two wettable powders (bactimos and vectobac) and one flowable concentrate (teknar) of bacillus thuringiensis var. israelensis (b.t.i.) and primary powders of bacillus sphaericus isolates 1593 and 2362 were evaluated (laboratory) against field-collected larvae of anopheles gambiae s.l. and culex quinquefasciatus in ouagadougou, burkina faso. bactimos, vectobac and a corn-cob b.t.i. formulation (abg-6138g) were field tested against cx. quinquefasciatus and an. gambiae s.l. the isolates of b. sphae ... | 1987 | 3504891 |
| an alternative bioassay employing neonate larvae for determining the toxicity of suspended particles to mosquitoes. | an alternative bioassay using neonate larvae of aedes aegypti is described for determining the toxicity of suspended particles, particularly insecticidal bacteria, to mosquitoes. this new assay is comparable in precision to the 4th instar bioassay recommended by the world health organization, but is quicker and requires much less space. values obtained using neonate larvae as the test insect showed less variation within and between replicates in regard to lc50 and slope of the regression line, a ... | 1987 | 3504908 |
| evaluation of larvicides for the control of simulium damnosum s.l. (diptera: simuliidae) in west africa. | the onchocerciasis control program of the world health organization is carrying out an extensive screening program in a search for new larvicides to be used for control of simulium damnosum s.l. emphasis has been given to finding a pyrethroid and a carbamate to supplement the organophosphates currently in use. these chemicals with differing modes of action, together with bacillus thuringiensis h-14, are being used in an attempt to cope with the development and spread of resistance to the organop ... | 1987 | 3504910 |
| efficacy of arosurf msf and formulations of bacillus thuringiensis var. israelensis against anopheles albimanus: laboratory bioassay. | the efficacy of arosurf msf alone and in combination with three preparations of bacillus thuringiensis var. israelensis (b.t.i.) against anopheles albimanus larvae, pupae and eggs was determined by bioassay. arosurf msf alone was effective against the egg, 4th larval instar and pupal stages. all arosurf msf and b.t.i. combined formulations produced over 90% mortality of all larvae and pupae, 48 hr posttreatment. egg eclosion was reduced to approximately 25% with all formulations containing arosu ... | 1987 | 3504934 |
| efficacy of bacillus sphaericus and bacillus thuringiensis var. israelensis for control of culex pipiens and floodwater aedes larvae in iowa. | granular and flowable concentrate formulations of bacillus thuringiensis var. israelensis provided a 90-100% reduction in aedes vexans and culex spp. larvae in natural larval habitats. a briquet formulation of b. thuringiensis was less effective, providing a 12-76% reduction. no residual activity occurred in sites treated with b. thuringiensis. granular formulations of bacillus sphaericus (2.78-8.42 kg/ha) caused a 100% reduction in culex pipiens larvae in natural sites and artificial pools. bac ... | 1987 | 3504943 |
| floating bait formulations increase effectiveness of bacillus thuringiensis var. israelensis against anopheles larvae. | the development and screening of floating-type bait formulations designed to improve the activity of bacterial toxins against larval anopheles is described. floating and spreading abilities of carrier particles (wheat flour) were compared using corn oil, lecithin, and two products yielding surface films on water (arosurf and liparol). mixtures containing 1 or 5% arosurf showed the best spreading abilities on a water surface, but strongly inhibited the ingestion of wheat flour by anopheles albima ... | 1987 | 3504944 |
| thin layer chromatography overlay technique in the analysis of the binding of the solubilized protoxin of bacillus thuringiensis var. kurstaki to an insect glycosphingolipid of known structure. | the hypothesis tested was that a particular glycoconjugate(s) in the exposed cell-surface membrane of susceptible insect cells acts as a receptor and/or modulator for the specific interaction with the protoxin/activated toxin of the delta-endotoxin of bacillus thuringiensis var. kurstaki. as candidates, the total neutral and acidic fraction glycolipids, and the isolated neutral glycosphingolipid components, were screened for binding activity by the thin layer chromatogram overlay technique. the ... | 1986 | 3506816 |
| effects of sublethal exposure to bacillus thuringiensis var. israelensis on larval development and adult size in aedes aegypti. | the effects of exposure to sublethal concentrations of bacillus thuringiensis var. israelensis (serotype h-14) on second instar aedes aegypti larvae were investigated. a test system was developed in which adverse effects would be detected as increased duration of larval development and decreased adult body size. no evidence of negative effects on survivors could be detected when sufficient b.t.i. dosages were applied to kill approximately half of the larvae in the treatment groups. however, when ... | 1986 | 3507506 |
| evaluation of a sustained release formulation of bacillus thuringiensis (h-14) for control of woodland culex mosquitoes. | | 1986 | 3507516 |
| swath width determination for beecomist-applied bacillus thuringiensis (h-14) against anopheles quadrimaculatus larvae in rice fields. | optimum flight path interval of beecomist-applied bacillus thuringiensis var. israelensis (serotype h-14) (bti) against anopheles quadrimaculatus larvae was determined by assessing the effective swath width in rice fields. droplet sensitive cards, laboratory-reared and naturally occurring populations of larvae were used to monitor aerial treatments 1 day posttreatment. overlapping swaths were necessary to provide high levels of larval reduction. based on tests where flight path intervals were 18 ... | 1986 | 3507523 |
| toxicity in carcasses of bacillus thuringiensis var. israelensis-killed aedes aegypti larvae against scavenging larvae: implications to bioassay. | | 1986 | 3507532 |
| the potassium impermeable apical membrane of insect epithelia: a target for development of safe pesticides. | columnar cell apical membranes (ccam) in series with goblet cell apical membranes (gcam) form an electroosmotic barrier separating the midgut lumen from epithelial cell cytoplasm. a unique k+ atpase in gcam generates three gradients across this barrier. a greater than 180 mv electrical gradient (lumen positive) drives amino acid uptake through voltage-dependent k+ symports. a greater than 1000-fold [h+] gradient (lumen alkaline) and a greater than 10-fold [k+] gradient (lumen concentrated) are a ... | 1987 | 3509112 |
| the inactivation of bacillus thuringiensis subsp. israelensis toxin by mosquito larvae proteases liberated into the medium. | crystal serine-proteases of b. thuringiensis subsp. israelensis were able to process the 28,000-dalton protein during crystal solubilization. on the other hand, solubilized crystal proteins were degraded during the larvicidal bioassay by the action of serine-proteases liberated by mosquito larvae into the medium, with loss of toxicity. however, proteins in intact crystals were protected from the action of these proteases. this resistance to degradation of crystals partly explains the observation ... | 1986 | 3516151 |
| bacteriophage-resistant mutants of bacillus thuringiensis with decreased virulence in pupae of hyalophora cecropia. | starting from a crystal-negative parental strain of bacillus thuringiensis, we isolated certain bacteriophage-resistant mutants which showed decreased virulence in pupae of the cecropia moth (hyalophora cecropia). these strains (class i mutants) were highly pleiotropic and showed resistance to seven or eight different phages, sensitivity to methicillin, and loss of flagella. they were also more sensitive to cecropia immune hemolymph in vitro. in addition, the export of at least three proteins wa ... | 1986 | 3522544 |
| development of sensitive bacterial tests, exemplified by two mycotoxins. | for a sensitive bacterial test for mycotoxins the cup plate assay, based on growth inhibition, was optimised with bacillus thuringiensis as test strain. bacillus thuringiensis allowed the detection of 1.25 microgram kojic acid. a minimal amount of 12.5 micrograms kojic acid or 1.25 micrograms patulin was detectable by means of pigment suppression with isolated mutants of serratia marcescens, whereas the wild type of this strain was insensitive. | 1986 | 3523832 |
| [chemical mutagenesis and the use of indirect enzymatic criteria for the selection of virulent clones of bacillus thuringiensis]. | the effect of the mutagene nitrosoguanidine (n-methyl-n'-nitro-n-nitrosoguanidine) on the growth of bacillus thuringiensis subsp. galleriae st. 69/6 was being studied. it depends on the physiological state of the cells, dose of the mutagene, ph of the culture medium and exposition. nitrosoguanidine was found to have the maximum mutagenic effect on the vegetative cells at ph 6.2 and on the spores at ph 5.6. | 1986 | 3532089 |
| the molecular biology of parasporal crystal body formation in bacillus thuringiensis. | data obtained using several experimental methods (curing, transconjugation, cloning, and hybridization) indicate that crystal protein genes in many subspecies of bt that are toxic to lepidopterans are located on one or more large plasmids; in some subspecies, the gene may be located on the chromosome. detailed mapping has shown that in three plasmids (each from a different strain) the genes are surrounded by multiple copies of two repeated dna elements; the arrangement of these elements is the s ... | 1986 | 3535652 |
| immunological relationships among proteins making up the bacillus thuringiensis subsp. israelensis crystalline toxin. | the immunological relationships among the proteins of the mosquito larvicidal toxin produced by bacillus thuringiensis subsp. israelensis have been investigated by using polyclonal antisera specific for the 28-, 70-, and 135-kilodalton proteins. each of these proteins was immunologically distinct. there was no cross-reaction among the three proteins and the two non-homologous antisera. treatment of toxin proteins with larval gut enzymes for 20 h identified protease-resistant domains at approxima ... | 1986 | 3535673 |
| expression in escherichia coli of a cloned crystal protein gene of bacillus thuringiensis subsp. israelensis. | a ca. 10-kilobase (kb) hindiii fragment of plasmid dna from bacillus thuringiensis subsp. israelensis was cloned into plasmid puc9 and transformed into escherichia coli. extracts of the recombinant strain contained a 27-kilodalton (kda) peptide that reacted with antibodies to a 27-kda peptide isolated from crystals produced by b. thuringiensis subsp. israelensis. extracts of the recombinant strain were hemolytic and toxic to aedes aegypti larvae. full expression of the 27-kda peptide required th ... | 1987 | 3546262 |
| [effectiveness of bacillus thuringiensis israelensis h-14 variety in different mosquito breeding grounds in the city of havana and santiago de cuba provinces]. | | 1986 | 3550961 |