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separation of protein crystals from spores of bacillus thuringiensis by ludox gradient centrifugation.a method is described for the purification of bacillus thuringiensis protein crystals by ludox gradient centrifugation. this method is simple, inexpensive, fast, and efficient compared with other techniques. it has been successfully used to purify and characterize the protein crystals from several b. thuringiensis strains.198916347918
protozoan response to the addition of bacterial predators and other bacteria to soil.representatives of several categories of bacteria were added to soil to determine which of them might elicit responses from the soil protozoa. the various categories were nonobligate bacterial predators of bacteria, prey bacteria for these predators, indigenous bacteria that are normally present in high numbers in soil, and non-native bacteria that often find their way in large numbers into soil. the soil was incubated and the responses of the indigenous protozoa were determined by most-probable ...198916347983
worldwide abundance and distribution of bacillus thuringiensis isolates.we found the insect control agent bacillus thuringiensis to be a ubiquitous soil microorganism. using acetate selection to screen soil samples, we isolated b. thuringiensis in 785 of 1,115 soil samples. these samples were obtained in the united states and 29 other countries. a total of 48% of the b. thuringiensis isolates (8,916 isolates) fit the biochemical description of known varieties, while 52% represented undescribed b. thuringiensis types. over 60% (1,052 isolates) of the isolates tested ...198916348022
a cytolytic delta-endotoxin from bacillus thuringiensis var. israelensis forms cation-selective channels in planar lipid bilayers.in order to determine the mechanism of action of the 27 kda mosquitocidal delta-endotoxin of bacillus thuringiensis var. israelensis we have studied its effects on the conductance of planar lipid bilayers. the toxin formed cation-selective channels in the bilayers, permeable to k+ and na+ but not to n-methylglucamine or cl-, showing very fast, cooperative opening and closing. channel opening was greatly reduced in the presence of divalent cations (ca2+, mg2+) and the effect was reversed when the ...19892465921
transformation of bacillus thuringiensis vegetative cells by electroporation.a highly efficient procedure for the transformation of bacillus thuringiensis and bacillus subtilis using covalently closed circular plasmid dna was developed by using the small staphylococcus aureus plasmid pc194 and electroporation. we have achieved transformation efficiencies in b. thuringiensis subsp. kurstaki (hd-73) greater than 5 x 10(6) transformants/micrograms plasmid dna. the electro-transformation (or electroporation) procedure also worked with b. subtilis 168 although at a 200-fold l ...19892583476
a broad evaluation of b.t.i. for black fly (diptera: simuliidae) control in a michigan river: efficacy, carry and nontarget effects on invertebrates and fish.efficacy for black fly control, carry and nontarget effects of b.t.i. (teknar hp-d), applied in the betsie river, michigan, were studied in june 1988. black fly mortality was high (approximately 100%) for a 2,200 m stretch downstream from the application site, declined to 30% at 3,200 m, and was nil at 4,500 m. drift of black flies greatly increased after application at a downstream site, but did not change at an upstream site. there were no detectable nontarget effects of b.t.i. application on: ...19892584974
characterization of a dynamic s layer on bacillus thuringiensis.the surfaces of three bacillus thuringiensis strains possess an s layer composed of linear arrays of small particles arranged with p2 symmetry and with a = 8.5 nm, b = 7.2 nm, and gamma = 73 degrees. platinum shadows of whole cells and s-layer fragments revealed the outer surface of the array to be smooth and the inner surface to be corrugated. treatment with 2 m guanidine hydrochloride at ph 2.5 to 4 best removed the s layer for chemical characterization; it was a relatively hydrophilic 91.4-ki ...19892592346
susceptibility of adult phlebotomine sandflies (diptera: psychodidae) to bacillus thuringiensis var. israeliensis. 19892604459
a novel phage genome integrated into a plasmid in bacillus thuringiensis strain af101.bacillus thuringiensis strain af101 possesses a single plasmid (paf101) with a molecular size of 42 mda (69 kb). during plasmid curing experiments in strain af101, we found that a phage (j7w-1) was induced by ethidium bromide treatment. moreover, the phage genome (48 kb) hybridized only with paf101 on a southern blot of the dna of a cleared lysate prepared from strain af101. comparison of the restriction patterns of paf101 and j7w-1 phage dna revealed that paf101 contains not only the entire pha ...19892614379
a new method of testing bacillus thuringiensis var. israelensis (h-14) formulations on aedes taeniorhynchus in an abandoned rice impoundment in south carolina. 19892614409
effect of bacillus thuringiensis israelensis (h-14) on the isopod asellus forbesi and spring aedes mosquitoes in michigan. 19892614410
specificity of bacillus thuringiensis for lepidopteran larvae: factors involved in vivo and in the structure of a purified protoxin.the relative ld50 values in two test lepidoptera of bacillus thuringiensis subspecies kurstaki hd1, which contains three cryla protoxin genes, was the same as a plasmid-cured derivative or a bacillus cereus transcipient containing only one of the three genes. differential rates of transcription of these genes in the original strain could account, at least partly, for this result. strains containing only the single protoxin gene (cryla(b] produced inclusions when grown at 25 degrees c but not 32 ...19892615654
[the effect of mineral salts on the growth and development of bacillus thuringiensis strain h14 266/2-1].potassium phosphates in the concentration of 1.0 g/l are the most favourable for the growth and development of the culture of bacillus thuringiensis h14 266/2-1. the data obtained may be used when optimizing the medium for the submerged cultivation of a bactoculicide producer.19892622399
binding and aggregation of the 25-kilodalton toxin of bacillus thuringiensis subsp. israelensis to cell membranes and alteration by monoclonal antibodies and amino acid modifiers.the 25-kilodalton toxin of bacillus thuringiensis subsp. israelensis binds irreversibly to aedes albopictus cells, choristoneura fumiferana cells, and erythrocytes. the binding to cells increased with both toxin concentration and time and when the cells were first preincubated with unlabeled toxin. binding data indicated a two- to threefold increase in the rate of binding after the amount of the membrane-bound toxin reached approximately 3.5 fmol/3 x 10(5) a. albopictus cells or 3.3. fmol/2 x 10 ...19892624459
growth & toxicity of bacillus thuringiensis var israelensis.chemically defined media containing glutamic acid, glutamine and aspartic acid at a 20 mm concentration individually supported abundant growth and sporulation of bacillus thuringiensis var israelensis. the parasporal crystals produced in these media were toxic to fourth instar larvae of culex pipiens quinquefasciatus say. the medium containing 20 mm of glutamine induced early sporulation of b. thuringiensis var israelensis. an lc50 value of 3.92 micrograms/l was obtained. calcium alginate and ag ...19892628294
action of activated 27,000 mr toxin from bacillus thuringiensis var. israelensis on malpighian tubules of the insect, rhodnius prolixus.the action of activated 27,000 mr toxin from bacillus thuringiensis var. israelensis (bti toxin) on malpighian tubules of rhodnius prolixus has been investigated. its binding to the tubules is slowed by low temperature but is not prevented even at 0 degree c. the binding is less effective at ph 10 than at ph7. pretreatment of the tubules with 0.1 mmol l-1 ouabain or bumetanide or 1 mumol l-1 5-hydroxytryptamine did not affect the toxicity of the toxin. the toxin causes very large changes in the ...19892632587
[use of bacteria in the control of medically important diptera]. 19892641395
genetic manipulations in auto-induced protoplasts of bacillus thuringiensis. 19892641396
a 20-kilodalton protein is required for efficient production of the bacillus thuringiensis subsp. israelensis 27-kilodalton crystal protein in escherichia coli.the 27-kilodalton (kda) mosquitocidal protein gene from bacillus thuringiensis subsp. israelensis has been cloned as a 10-kilobase (kb) hindiii fragment from plasmid dna; efficient expression in escherichia coli km1 depends on a region of dna located approximately 4 kb upstream (k. mclean and h. r. whiteley, j. bacteriol. 169:1017-1023, 1987). we have cloned the upstream dna region and show that it contains a complete open reading frame (orf) encoding a protein with a molecular mass of 19,584 da ...19892644205
formation of crystals of the insecticidal proteins of bacillus thuringiensis subsp. aizawai ipl7 in escherichia coli.escherichia coli jm103 cells harboring expression plasmid ptb1 or pkc6 synthesized the 130- and 135-kilodalton insecticidal proteins, respectively, of bacillus thuringiensis subsp. aizawai ipl7, and both products accumulated as cytoplasmic inclusion bodies. amorphous inclusions which contained contaminating proteins, together with the corresponding insecticidal proteins, were formed in cultures at 37 degrees c, but bipyramidal crystals practically free of contaminants were observed at 30 degrees ...19892656661
insecticidal crystal proteins of bacillus thuringiensis.a classification for crystal protein genes of bacillus thuringiensis is presented. criteria used are the insecticidal spectra and the amino acid sequences of the encoded proteins. fourteen genes are distinguished, encoding proteins active against either lepidoptera (cryi), lepidoptera and diptera (cryii), coleoptera (cryiii), or diptera (cryiv). one gene, cyta, encodes a general cytolytic protein and shows no structural similarities with the other genes. toxicity studies with single purified pro ...19892666844
[bacillus thuringiensis fluorescence induced by anaerobiosis and its relation to the cellular functional state].the fluorescence spectra of bacillus thuringiensis native cells at 340 nm induction have been investigated. the spectral curve has 440-445 and 510-515 nm maximums of fluorescence of pyridine nucleotides (pn) and flavoproteins (fp). the induction of pn and fp fluorescence under anaerobiosis resulted from bacterium breath has been found. the fluorescence induction is connected with the viability of cells. the amplitude of induced fluorescence is in a linear dependence on the number of vegetative c ...19892669979
[the effect of the method of inoculation on the growth and variability of bacillus thuringiensis h14 266/2-1].the method of inoculation was studied for its effect on the growth and variability of bacillus thuringiensis h14 266/2-1 when cultivating them in the liquid nutrient medium inoculate with inoculum prepared by different procedures. optimal conditions of the inoculum preparation are determined. productivity of the strain when inoculating the medium with the aerial-dry inoculum was studied as compared to the inoculation by the inoculum taken from the mown agar. it is established that selection of t ...19892695795
[ineffectiveness of bacterial insecticides against egg laying by female mosquitoes].insecticides on the base of bacillus thuringiensis and b. sphaericus proved to be ineffective against laying of eggs by female mosquitoes in the water containing these formulations.19892710050
thuricin: the bacteriocin produced by bacillus thuringiensis.bacillus thuringiensis serovar, thuringiensis (hd-2) demonstrated antibacterial activity against 48 of 56 strains of b. thuringiensis and against some other gram-positive species but not against gram-negative species. the antibacterial activity was not inducible by mitomycin c or by ultraviolet irradiation, and additional activity was not liberated from cells by sonication. upon dilution of the antibacterial substance, zones of inhibition diminished without the appearance of plaques. gel filtrat ...19892723445
activity of commercial bacillus thuringiensis preparations against trichostrongylus colubriformis and nippostrongylus brasiliensis. 19892723447
[intraspecies plasmid transformation of bacillus thuringiensis].bacillus thuringiensis strains 1009, 3004, 3029 of the natural isolates of var. dendrolimus harbouring two large plasmids were transformed by a mix of small plasmids dna. one of transforming plasmids carried a gene for tetracyclinresistance. the natural isolates of var. dendrolimus strain 2002 and var. berliner strain 1035 were used as donors for plasmid dna transformation. three variants of plasmid spectra registered in tetracycliresistant transformants are discussed.19892725537
functional relationships between free amino acids in the hemolymph of fourth instar larvae of the mosquito aedes aegypti (diptera, culicidae) as a basis for toxicological studies.characteristic correlations reflecting particular metabolic interactions between free amino acids have been pointed out and used as a sensitive test for the detection of biochemical intoxication symptoms in fourth instar larvae of the mosquito aedes aegypti exposed for 0-8, 12, 24, and 36 hr to various doses of bacillus thuringiensis delta-endotoxin ranging from 0.01 to 1 mg liter-1. in a first pool, serine was negatively correlated with glycine while cystine and alanine were positively correlat ...19892738416
mortality in adult tsetse, glossina morsitans morsitans, caused by entomopathogenic bacteria.mortality in adult tsetse, glossina morsitans morsitans, caused by pseudomonas aeruginosa, serratia marcescens, bacillus sphaericus, bacillus cereus, bacillus thuringiensis h-14, b. thuringiensis 1, b. thuringiensis 5, b. thuringiensis var. insraelensis, and providentia rettgeri was determined. when bacteria were smeared on rabbit skin and tsetse allowed to feed only once on the contaminated area, mortality 8 days postingestion was significantly higher (p less than 0.01) in tsetse fed on p. aeru ...19892738417
expression of an nca cdna in nih/3t3 cells yields a 110k glycoprotein, which is anchored into the membrane via glycosyl-phosphatidylinositol.the nca cdna, which represents a gene belonging to the cea family, was inserted into an sv40 early promoter-driven expression vector and used for transfection of mouse nih/3t3 cells. a cell line, nih/3t3/knca ig7, was selected which expressed a molecule with an apparent molecular weight of 110,000. the mode of membrane attachment of this nca, which we already proposed to be anchored via glycosyl-phosphatidylinositol, was investigated by treatment of nih/3t3/knca ig7 cells with phosphatidylinosit ...19892742579
[biochemical diagnosis of the presence of poisoning by bacillus thuringiensis serotype "h3a,3b" in two lepidopterans].a detailed biochemical analysis has shown that during larval development on artificial medium, the amounts of k+, na+, and ca2+ in the hemolymph of healthy choristoneura fumiferana varied from 85 to 110 mg/100 ml, 29 to 33 mg/100 ml, and 4.8 to 7.3 mg/100 ml, respectively. similar results were obtained with malacosoma disstria. intoxication by bacillus thuringiensis "h3a,3b" (b. t.) considerably modified the amounts of the cations. thus, after 4 h, the quantity of k+ in m. disstria increased fro ...19892743217
a screening for the presence of four different crystal protein gene types in 25 bacillus thuringiensis strains.25 different strains of bacillus thuringiensis, belonging to 18 different serotypes were screened by southern hybridization analysis for the presence of nucleotide sequences of four different gene types coding for crystal proteins showing different insecticidal spectra. many but not all strains showed sequences homologous to any of the probes used. homology with sequences of the gene type present in strain kurstaki hd1 occurred in all positive strains, whereas the other gene types were much less ...19892744415
delineation of the toxin coding fragments and an insect-specificity region of a dual toxicity bacillus thuringiensis crystal protein gene.a series of deletion mutants have been constructed from the dual toxicity bacillus thuringiensis aizawai ic1 (bta ic1) crystal protein gene. the mutant toxin genes were expressed in escherichia coli, their protein products purified and the authenticity of these mutant proteins confirmed immunologically. analysis of the toxicity spectra of these mutants revealed that lepidopteran toxicity is located on the n-terminal region of the toxin between residues ile30-glu595. 3' deletion of a further 37 r ...19892744417
[experiences in conducting studies of toxicologic evaluation of industrial microorganisms for the purpose of their hygienic standardization]. 19892744520
release of pi-anchoring enzymes and other effects of phosphatidylinositol-specific phospholipase c from bacillus thuringiensis on tn-368 cells from a moth ovary.release of pi-anchoring enzymes and other effects of phosphatidylinositol-specific phospholipase c from bacillus thuringiensis on tn-368 cells from a moth ovary. toxicon 27, 637-645, 1989.--the effect of phosphatidylinositol-specific phospholipase c(piplc) from bacillus thuringiensis was investigated on tn-368 cells, derived from the ovary of a moth, trichoplusia ni. quantitative analysis of lipids showed that phosphatidylinositol (pi) was contained as one of the major phospholipids in tn-368 ce ...19892749761
functional mapping of an entomocidal delta-endotoxin. single amino acid changes produced by site-directed mutagenesis influence toxicity and specificity of the protein.mutagenesis has been used to investigate the toxicity and specificity of a larvicidal protein from bacillus thuringiensis aizawai ic1 that is toxic to both lepidoptera and diptera and differs by only three residues from a monospecific lepidopteran toxin from b. thuringiensis berliner. site-directed mutagenesis was used to investigate the contribution of these residues to the dual specificity of the aizawai protein. the results suggest that changes in the identity of residues adjacent to arg544 a ...19892769751
[site-specific restriction endonuclease btci from bacillus thuringiensis var. canadensis].efficiency of bacteriophage tp4 plating on bacillus thuringiensis var. canadensis h5 (can) is decreased 10(7)-fold as compared with the efficiency of plating on bacillus thuringiensis var. galleriae h5 (gal). bacteriophage tp4 having propagated for one cycle in can cells might be further grown in this strain without restriction. the sitespecific restriction endonuclease btci isolated from bacillus thuringiensis var. canadensis recognises the same nucleotide sequence gatc in dna as recognised by ...19892787475
characterization of the mammalian toxicity of the crystal polypeptides of bacillus thuringiensis subsp. israelensis.solubilized crystal polypeptide preparations of bacillus thuringiensis subsp. israelensis (bti) were fractionated by immunoaffinity chromatography using a bound monoclonal antibody formed against the 28k crystal polypeptide. the 28k polypeptide was confirmed to be hemolytic and to possess low mosquitocidal activity against aedes aegypti larvae. by comparison, the 28k polypeptide was more potent than the solubilized bti crystals in male swiss webster mice, as the ld50 values were (p less than 0.0 ...19892792598
two forms of plasma membrane-intercalated heparan sulfate proteoglycan in rat ovarian granulosa cells. labeling of proteoglycans with a photoactivatable hydrophobic probe and effect of the membrane anchor-specific phospholipase c.the structures of cell-associated heparan sulfate (hs) proteoglycans and their interaction with the plasma membrane was studied using rat ovarian granulosa cell culture. hs proteoglycans were either metabolically labeled by incubating cell cultures with [3h] leucine and [35s]sulfate or labeled in plasma membrane preparations with a photoactivatable reagent, 3-(trifluoromethyl)-3-(m-[125i]iodophenyl)diazirine (tid), a compound which has been shown to selectively label the hydrophobic membrane-bin ...19892793870
[structure and biological features of the temperate phage of bacillus thuringiensis var. galleriae 69/9, sensitive to chloroform].a new temperate bacteriophage designated px1 has been isolated from the culture of bacillus thuringiensis var. galleriae 69/6 producing enthobacterin. the bacteriophage belongs to morphological group b1 in accordance with the classification by d. reanney and h. ackerman. the bacteriophage head has an isometric multifaceted form with 40 nm diameter. the length of its noncontractile transversely lined tail is 130 nm. high sensitivity to chloroform is peculiar of the phage. the lytical specter of t ...19892811909
isolation of carboxyl-terminal peptides from proteins by diagonal electrophoresis: application to the entomocidal toxin from bacillus thuringiensis.a procedure for the selective isolation of the c-terminal peptides from enzymatic digests of proteins is described. the methodology is based on the diagonal electrophoretic procedure described by r. g. duggleby and h. kaplan (1975) anal. biochem. 65, 346-354). the carboxyl groups in the protein are amidated with [14c]-methylamine followed by enzymatic digestion. since only the c-terminal peptides lack a free carboxyl group, these peptides will lie on a diagonal line of a two-dimensional electrop ...19892817385
nucleotide sequence of a gene cloned from bacillus thuringiensis subspecies entomocidus coding for an insecticidal protein toxic for bombyx mori. 19892911478
two highly related insecticidal crystal proteins of bacillus thuringiensis subsp. kurstaki possess different host range specificities.two genes encoding insecticidal crystal proteins from bacillus thuringiensis subsp. kurstaki hd-1 were cloned and sequenced. both genes, designated cryb1 and cryb2, encode polypeptides of 633 amino acids having a molecular mass of ca. 71 kilodaltons (kda). despite the fact that these two proteins display 87% identity in amino acid sequence, they exhibit different toxin specificities. the cryb1 gene product is toxic to both dipteran (aedes aegypti) and lepidopteran (manduca sexta) larvae, whereas ...19892914879
factors influencing lethality of bacillus thuringiensis kurstaki toxin for eggs and larvae of trichostrongylus colubriformis (nematoda).a toxin from bacillus thuringiensis kurstaki was lethal to eggs and first- and second-stage larvae of the ruminant nematode trichostrongylus colubriformis. sheathed and exsheathed third-stage larvae were also killed by the toxin. however, susceptibility of the ova to the toxin decreased after several hours of development. heating at 65 c for 1 hr or freezing at 0 c for 3 mo did not affect stability of the toxin. ovicidal activity of the toxin was not altered by treatment with 13 microbial or mam ...19892926587
acute toxicity of temephos, fenoxycarb, diflubenzuron, and methoprene and bacillus thuringiensis var. israelensis to the mummichog (fundulus heteroclitus). 19892480827
expression of the insecticidal protein gene from bacillus thuringiensis subsp. aizawai in bacillus subtilis and in the thermophile bacillus stearothermophilus by using the alpha-amylase promoter of the thermophile.expression of the insecticidal protein gene from bacillus thuringiensis subsp. aizawai ipl7 in b. subtilis mi113 and b. stearothermophilus sic1 was examined. production of the protein (130 kilodaltons [kda]) was analyzed by its reaction with antibody against the insecticidal proteins of the parental b. thuringiensis. when the original gene containing its own promoter was subcloned in b. subtilis, only a small amount of the protein was produced. therefore, both the promoter for the b. stearotherm ...19892482704
absorption edge imaging of bacterial endospores with synchrotron radiation.this article describes a new method of viewing biological specimens by taking advantage of the absorptive characteristics of monochromatic x-rays above and below the absorption edge of a specific element. bacterial endospores were imaged before and after treatment with an experimental vanadium-containing sporocide using monochromatic synchrotron radiation at the nitrogen absorption edge, and above and below the vanadium liii absorption edge. this morphological study demonstrates a rapid, easy-to ...19892496511
[plasmid transduction by bacillus anthracis bacteriophage cp54].possibility of plasmid transduction in bacillus anthracis vaccine strains sterne and sti-1 by bacteriophage cp54ant having an increased ability of adsorbtion and a shortened period of latent development in bacillus anthracis cells has been isolated. the main parameters of plasmid transduction by the bacteriophage have been established for the plasmid ptg141 (tcr). they include the effect of multiplicity of infection, the level of uv-inactivation of bacteriophage, the presence of antiphage serum ...19892499772
identification of bacillus anthracis by polyclonal antibodies against extracted vegetative cell antigens.the extractable protein antigens ea1 and ea2 of bacillus anthracis were prepared from electrophoresis transblots of sds extracts of vegetative bacteria of the sterne strain. hyperimmune guinea-pig antiserum against ea2 failed to react with b. anthracis cells in immunofluorescence (if) tests. guinea-pig antiserum against ea1 (anti-ea1) reacted strongly in if tests with non-encapsulated vegetative cell of 10 of 12 strains of b. anthracis and with cells of strains of b. cereus and b. thuringiensis. ...19892502530
cloning of a gene encoding a major secreted polypeptide of listeria monocytogenes and its potential use as a species-specific probe.a gene, designated msp, that encodes a major secreted polypeptide with a molecular mass of approximately 60 kilodaltons (kda) was cloned from listeria monocytogenes 10403. dna hybridization analysis indicated that the msp gene was highly conserved among 15 independent l. monocytogenes isolates and that each of 5 isolates tested secreted a 60-kda polypeptide that was immunologically related to the msp gene product. dna sequences related to msp were not detected in any other listeria species or in ...19892508555
accumulation of the insecticidal crystal protein of bacillus thuringiensis subsp. kurstaki in post-exponential-phase bacillus subtilis.a gene from bacillus thuringiensis subsp. kurstaki that codes for a lepidoptera-specific insecticidal toxin (delta-endotoxin) was engineered for expression in bacillus subtilis. a low-copy-number plasmid vector that replicates in escherichia coli and b. subtilis was constructed to transform b. subtilis with gene fusions first isolated and characterized in e. coli. naturally occurring promoter sequences from b. subtilis (43, veg, ctc, and spovg) were inserted upstream from the plasmid-borne struc ...19892508556
ultrastructural effects of macrotetrolides of streptomyces griseus lks-1 in tissues of culex pipiens larvae.the isolate of macrotetrolides produced by streptomyces griseus strain lks-1 was tested in its effect on the ultrastructure of larvae of culex pipiens autogenicus. changes were mainly in mitochondria where the cristae were destroyed and the outer membrane inflated. the endoplasmic reticulum was vacuolized and subsequently the nuclear membranes were seriously affected. microvilli of the midgut epithelial cells and the surface membrane of these cells were unaltered and there were no changes in the ...19892509144
[transduction ability of mutants of phage cp51, virulent for bacteria of the bacillus cereus group].the virulent phage cp51 used usually to transfer chromosomal and plasmid markers between bacteria of the bacillus cereus group was treated with n-methyl-n'-nitro-n-nitroguanidine. mutants with reduced viability and ts-mutants were isolated. some of the mutants were found to have an increased efficiency of transduction and allow to simplify the process. transfer frequencies of the plasmid pbc16 by the phages cp51-26 and cp51-4-59 were 5 x 10(-4) per plaque-forming unit and 4-5 x 10(-3) per bacter ...19892509285
a comparative study of enzyme variation in bacillus cereus and bacillus thuringiensis.thirty-two strains of bacillus spp. were examined in a multilocus enzyme study by agarose gel electrophoresis. the organisms were bacillus thuringiensis (21 strains, b. cereus (8), including two of var. mycoides, and b. megaterium (3). strains having similar enzyme variants were grouped into zymovars. a total of 10 of 11 enzyme loci studied were polymorphic and 27 zymovars were distinguished among the 32 strains. the results were subjected to numerical analysis, phenetic affinities and genetic d ...19892515182
[the use of plasmid screening for the differentiation of bacillus anthracis strains from closely related species of soil bacilli].b. anthracis virulent and vaccine strains differ from the strains of species closely related to b. anthracis, such as b. cereus and b. thuringiensis, in their plasmid spectrum. the use of their plasmid spectrum. the use of the plasmid analysis of the strain is recommended for laboratory practice as the main differential diagnostic test.19892515698
mechanism of action of bacillus thuringiensis insecticidal delta-endotoxin: interaction with phospholipid vesicles.bacillus thuringiensis (bt) crystal delta-endotoxin from three subspecies and the product of a cloned crystal protein gene were activated in vitro and their interaction with phospholipid liposomes studied. despite their diverse spectrum of activity, all these toxins were found to cause a rapid increase in the light scattering of liposome suspensions, which reflects a morphological change in the lipid bilayer. when liposomes loaded with radioactive markers were incubated with b. thuringiensis aiz ...19892536557
involvement of tn4430 in transfer of bacillus anthracis plasmids mediated by bacillus thuringiensis plasmid pxo12.the self-transmissible plasmid pxo12 (112.5 kilobases [kb]), originally isolated from strain 4042a of bacillus thuringiensis subsp. thuringiensis, codes for production of the insecticidal crystal protein (cry+). the mechanism of pxo12-mediated plasmid transfer was investigated by monitoring the cotransfer of the tetracycline resistance plasmid pbc16 (4.2 kb) and the bacillus anthracis toxin and capsule plasmids, pxo1 (168 kb) and pxo2 (85.6 kb), respectively. in matings of b. anthracis donors wi ...19892536653
expression of a cloned bacillus thuringiensis delta-endotoxin gene in bacillus subtilis.the entire coding region of the bacillus thurigiensis hd73 crystal protein gene was subcloned from plasmid pjwk20 into the integration vector pug2-15. this plasmid expresses chloramphenicol resistance when integrated into the bacillus subtilis chromosome in the outh locus near the rece region. the correct molecular organization of the integrated plasmid was verified by hybridization to southern blots of chromosomal dna digests. production of the toxic crystal protein was monitored at different t ...19892541663
location of the bombyx mori specificity domain on a bacillus thuringiensis delta-endotoxin protein.bacillus thuringiensis produces different types of insecticidal crystal proteins (icps) or delta-endotoxins. in an effort to identify the insect specificity of icp toxins, two icp genes were cloned into the escherichia coli expression vector pkk223-3, and bioassays were performed with purified crystals. the type a protein [from an icpa1, or 4.5-kilobase (kb) gene, from b. thuringiensis var. kurstaki hd-1] was found to be 400 times more active against bombyx mori than type c protein (from an icpc ...19892542961
nucleotide sequence and characterization of a new insertion element, is240, from bacillus thuringiensis israelensis.the nucleotide sequence of two repeated sequences (rs) in opposite orientations flanking the 125-kda toxin gene of bacillus thuringiensis israelensis (c. bourgouin et al., j. bacteriol. 170, 3575-3583, 1988) is reported in this paper. the analysis of these sequences indicates that these two rs display characteristic features of bacterial insertion sequences (is) and are therefore referred to as is240. is240 b is 865 bp long and has two perfect terminal-inverted repeats of 16 bp; is240 a is 99% i ...19892543009
phosphatidylinositol-specific phospholipase c of bacillus thuringiensis as a probe for the distribution of phosphatidylinositol in hepatocyte membranes.phosphatidylinositol-specific phospholipase c (pi-plc) produced by bacillus thuringiensis has been used as a probe for the distribution of phosphatidylinositol in hepatocyte membranes. approx. 50% of this phospholipid was hydrolysed in microsomal vesicles (endoplasmic reticulum) with no significant hydrolysis of the remaining membrane phospholipids. latency of mannose-6-phosphatase was retained during treatment indicating that the vesicles remained impermeable. stripping of the ribosomes did not ...19892543374
[strains of bacillus thuringiensis subspecies produce two delta- endotoxins in various ratios]. 19892544389
transformation of bacillus thuringiensis by electroporation.plasmids were transformed by electroporation into various strains of bacillus thuringiensis with frequencies of up to 10(5) transformants/micrograms. pc 194 transformed all strains tested at a high frequency and cells could be stably transformed with pc194 and pub110 simultaneously by electroporation with a frequency of 10(2) pc194+ pub110 transformants/micrograms dna. low transformation frequencies observed with some plasmids, especially those grown initially in escherichia coli, could be incre ...19892545517
nucleotide sequence and analysis of the n-terminal coding region of the spodoptera-active delta-endotoxin gene of bacillus thuringiensis aizawai 7.29.the nucleotide sequence of a 2711bp dna segment which contains the n-terminal coding sequence and the 5' flanking region of a crystal protein gene (bta) from bacillus thuringiensis subsp. aizawai 7.29 has been determined. the coding region encodes an 824 amino-acid polypeptide corresponding to a carboxy-terminally truncated delta-endotoxin specifically active against the cotton leaf worm spodoptera littoralis. comparison of the deduced amino acid sequence of the bta gene with that of the 4.5, 5. ...19892548060
molecular characterization and sequence of phosphatidylinositol-specific phospholipase c of bacillus thuringiensis.the gene encoding monophosphatidylinositol inositol phosphohydrolase (pi-specific phospholipase c, pi-plc) of bacillus thuringiensis was cloned in staphylococcus carnosus tm300. the complete coding region comprises 987 base pairs corresponding to a precursor protein of 329 amino acids (molecular weight, 38,095). the nh2-terminal sequence of the purified enzyme from escherichia coli indicated that the mature pi-plc consists of 299 amino acid residues with a molecular weight of 34,586. polyacrylam ...19892548063
[cloning and comparative characteristics of genes coding two structurally distant delta-endotoxins of bacillus thuringiensis var. galleriae and kurstaki].representative total dna libraries of bac. thuringiensis var. kurstaki (strain dipel) and galleriae (strain 11-67) have been constructed on the basis of phasmid vector lambda psl5. recombinant phasmid clones, carrying delta-endotoxin-coding genes of both subspecies have been isolated by means of immunoenzyme screening. restriction mapping and partial nucleotide sequence determination have demonstrated that phasmid lambda poc2, isolated from var. kurstaki dna library, contains the complete delta- ...19892549394
facile preparation and characterization of the toxin from bacillus thuringiensis var. kurstaki.we report a simple three-step method of generating a homogeneous toxic fragment (toxin) in high yield from b. thuringiensis var. kurstaki. purified crystals were digested with trypsin at ph 10.5, followed by (nh4)2so4 precipitation and dialysis. for the hd73 strain the preparation is toxic to eastern-spruce-budworm (choristoneura fuminiferana) larvae. it gives a single 66 kda band on polyacrylamide-gel electrophoresis and a single band with an isoelectric point of 5.5 on an isoelectric-focusing ...19892549961
proteolytic processing of a coleopteran-specific delta-endotoxin produced by bacillus thuringiensis var. tenebrionis.insecticidal protein delta-endotoxin crystals harvested from sporulated cultures of bacillus thuringiensis var. tenebrionis contain a major polypeptide of 67 kda and minor polypeptides of 73, 72, 55 and 46 kda. during sporulation, only the 73 kda polypeptide could be detected at stage i. the 67 kda polypeptide was first detected at stage ii and increased in concentration throughout the later stages of sporulation and after crystal release, with a concomitant decrease in the 73 kda polypeptide. t ...19892549968
transformation and expression of a cloned delta-endotoxin gene in bacillus thuringiensis.a shuttle vector containing the replication region of a resident plasmid of b. thuringiensis, was used to determine the conditions allowing efficient transformation of b. thuringiensis by electroporation. using this plasmid a delta-endotoxin gene was cloned and expressed both in escherichia coli and b. thuringiensis. it was shown that this gene was poorly expressed in the wild type situation whereas after cloning in acrystalliferous strains of b. thuringiensis large amounts of crystal protein we ...19892550317
gene dosage effect on the expression of the delta-endotoxin genes of bacillus thuringiensis subsp. kurstaki in bacillus subtilis and bacillus megaterium.significant differences in expression of the delta-endotoxin genes crya1 and crya2 of bacillus thuringiensis subsp. kurstaki were observed in b. subtilis and b. megaterium. the crya1 gene was expressed when present on a high-copy-number (hcn) vector in b. megaterium but not in b. subtilis. the crya2 gene was expressed in both hosts, but at a higher level in b. megaterium. expression of the crya2 gene in b. megaterium was better from a hcn vector than from a low copy number vector. inhibition of ...19892550328
efficient transformation of bacillus thuringiensis and b. cereus via electroporation: transformation of acrystalliferous strains with a cloned delta-endotoxin gene.electroporation was used as a method to transform intact cells of bacillus thuringiensis and b. cereus. with our optimized method a range of plasmid vectors could be transformed into strains of b. thuringiensis at frequencies of up to 10(7) transformants/micrograms dna. this high frequency allows cloning experiments to be done directly in b. thuringiensis. a bifunctional vector capable of replicating in escherichia coli and in bacillus spp. was constructed. the kurhd1 protoxin gene was cloned in ...19892550762
radioimmunoassay of delta-toxin from b. thuringiensis: correlation with bioassay.a radioimmunoassay procedure, developed for delta-toxin of b. thuringiensis, is applicable to the assay of the toxin's bioactivity. when delta-toxin is inactivated to different degrees by heat treatment, the amount of toxin as determined by radioimmunoassay is proportionally decreased. it thus appears that the delta-toxin antibody may recognize and bind to the conformation in the molecule associated with its insecticidal activity.19892551079
biosynthesis of 130-kilodalton mosquito larvicide in the cyanobacterium agmenellum quadruplicatum pr-6.the 130-kilodalton mosquito larvicidal gene, cloned from bacillus thuringiensis var. israelensis, was introduced into the cyanobacterium agmenellum quadruplicatum pr-6 by plasmid transformation. transformed cells synthesized 130-kilodalton delta-endotoxin protein and showed mosquito larvicidal activity. results demonstrate a potential use of a cyanobacterium for biological control of mosquitoes.19892552921
improved purification and biochemical properties of phosphatidylinositol-specific phospholipase c from bacillus thuringiensis.monophosphatidylinositol inositol phosphohydrolase (phosphatidylinositol-specific phospholipase c. ptdins-plc. ec 3.1.4.10) has been purified from a bacillus thuringiensis culture supernatant and from the cellular fraction of a recombinant escherichia coli clone containing the ptdins-plc gene from b. thuringiensis. the two-step purification procedure involved ion-exchange chromatography on deae-sepharose followed by separation on a mono-q/fplc-column with yields of 32% and 50%, respectively. the ...19892553399
molecular cloning and expression of bacillus thuringiensis subsp. galleriae insecticidal crystal protein genes in escherichia coli.the location of the toxin gene of b. thuringiensis subsp. galleriae (h5ab) on the mr-130md plasmid is determined by molecular cloning. double digestion fragments (bamhi and sali) and psti restriction fragments as well, from the 130 md plasmid, of b. thuringiensis subsp. galleriae, are ligated with the cloning vector pat 153 respectively and transformed into e. coli strain hb 101. out of 208 transformants, three colonies (fg2, fg9, fg19) give positive hybridization reaction using the hd-1 delta-e ...19892554939
specificity of bacillus thuringiensis delta-endotoxins. importance of specific receptors on the brush border membrane of the mid-gut of target insects.to study the molecular basis of differences in the insecticidal spectrum of bacillus thuringienesis delta-endotoxins, we have performed binding studies with three delta-endotoxins on membrane preparations from larval insect mid-gut. conditions for a standard binding assay were established through a detailed study of the binding of 125i-labeled bt2 toxin, a recombinant b. thuringiensis delta-endotoxin, to brush border membrane vesicles of manduca sexta. the toxins tested (bt2, bt3 and bt73 toxins ...19892557209
functional characteristics of phosphatidylinositol-specific phospholipases c from bacillus cereus and bacillus thuringiensis.phosphatidylinositol-specific phospholipase c was purified from the culture medium of b. thuringiensis to high specific activity using a procedure we recently described for purification of pi-plc from b. cereus (volwerk et al. (1989) j. cell. biochem. 39, 315-325). the purified enzymes from b. thuringiensis and b. cereus have similar specific activities towards hydrolysis of the membrane lipid phosphatidylinositol, and also towards hydrolysis of the glycosyl-phosphatidylinositol-containing membr ...19892558947
[proteins and proteinase-resistant polypeptides of delta-endotoxins from bacillus thuringiensis and their insecticidal activity].proteins, solubility in alkaline buffer and proteinase-resistant polypeptides (prp) of parasporal crystals (delta-endotoxin) from bacillus thuringiensis were investigated. 19 sorts of crystals were divided into 7 types. difference of crystalline proteins were coincident with their solubility and prp. the characters of the protein, solubility and prp were subspecies-specific basically, but in a few of crystals they were strain-specific. there was a closed relation between the biochemistry propert ...19892560877
[the role of bitoxibacillin components in the manifestation of its biological activity].new methods were developed and applied to quantitative determination of beta-exotoxin and antibiotic activity of delta-endotoxin with respect to micrococcus spp. in bitoxibacillin (btb) and the fermentation broths prepared under industrial conditions. the biosynthesis of beta-exotoxin in the period of its maximum accumulation during the fermentation was estimated. it was shown that the primary biological effect of btb on insects consisted in the actions of beta-exotoxin and delta-endotoxin. biol ...19892561254
cloning and expression of delta-endotoxin gene of bacillus thuringiensis in escherichia coli.fragments (larger than 4 kb) of partially sau 3ai-digested plasmid dna from bacillus thuringiensis subsp. kenyae 7404 and kurstaki hd-1 were cloned into the bamh i site of pbr322. four transformants, containing the corresponding delta-endotoxin gene and producing proteins that reacted with antiserum against crystalline protein, were selected on the basis of results from in situ colony hybridization, radioimmunologic screening, and western blot analysis. three of those tested, i.e., the lysates o ...19892562364
effect of bacillus sphaericus and bacillus thuringiensis on acid-phosphatase activity of mosquito larvae, culex pipiens and aedes caspius.the use of bacillus sphaericus and b. thuringiensis h-14 form one of the important group of biological control agent against mosquito larvae. acid phosphatase enzyme plays a significant role in determining susceptibility of mosquito larvae to both bacterial species. biochemical assay showed activation in acid phosphatase in culex pipiens and aedes caspius treated with b. thuringiensis. variation in acid phosphatase activity occurred in both mosquitoes treated with b. sphaericus, while there was ...19892565356
purification and properties of a 28-kilodalton hemolytic and mosquitocidal protein toxin of bacillus thuringiensis subsp. darmstadiensis 73-e10-2.the mosquitocidal crystal of bacillus thuringiensis subsp. darmstadiensis 73-e10-2 was purified, bioassayed against third-instar aedes aegypti larvae (50% lethal concentration, 7.5 micrograms/ml), and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, revealing polypeptides of 125, 50, 47, and 28 kilodaltons (kda). when solubilized and proteolytically activated by insect gut proteases or proteinase k, the crystal was cytotoxic to insect and mammalian cells in vitro and was h ...19892566594
efficacy of duplex and vectobac against psorophora columbiae and anopheles quadrimaculatus larvae in arkansas ricefields. 19892568399
evidence for two different types of insecticidal p2 toxins with dual specificity in bacillus thuringiensis subspecies.analysis of polypeptides in the crystalline delta-endotoxins from different bacillus thuringiensis strains revealed two antigenically similar forms of the p2 protein which differed in molecular mass, peptide profile, and amino acid sequence. purified preparations of the two forms displayed the characteristic dual toxicity of the p2 protein towards members of the orders lepidoptera and diptera in vivo but differed markedly in potency for the insects tested. both species of the p2 protoxin, solubi ...19892570060
[intensification of the growth and development of bacillus thuringiensis h14 266/2-1 by optimizing the nutrient medium].the mathematical method of experimental design was used to develop a new enzymic medium for cultivation of bacillus thuringiensis h14 266/2-1, a bactoculicide producer. the optimized medium based on corn flour enzyme lysate as a carbon source and fodder yeast enzyme lysate as a source of nitrogen amine made it possible to increase twice the titre biomass yield for 24 h cultivation as compared to the initial medium. the above medium does not yield to the initial production medium in the insectici ...19892576097
new facts and trends in bacteriological control of mosquitoes. 19892577058
the development of bacillus thuringiensis and bacillus sphaericus as biocontrol agents: from research to industrial production. 19892577059
restriction map of large plasmid pfw1 in bacillus sphaericus strain 10.some strains of bacillus sphaericus have been found to be toxic to mosquito larvae (1). they differ from bacillus thuringiensis var. israelensis (bti) (2,3) in the following aspects: bti is relatively ineffective in polluted water, and its residual activity in most habitats is limited to a few days after treatment, whereas bs isolates are effective in such habitats, particularly against species of culex; bs also remains effective longer, as a result of either persistence or recycling. b. sphaeri ...19892577477
phosphatidylinositol-attached 5'-nucleotidase from synaptic plasma membrane of rat brain.synaptic plasma membranes (spm) of rat brain contained a 5'-nucleotidase that was specifically released by bacillus thuringiensis phosphatidylinositol-specific phospholipase c (piplc). about 30% of the enzyme was readily released and the remainder was less susceptible. purified 5'-nucleotidase was treated with piplc and the resultant enzyme was almost totally partitioned into the detergent-poor phase following phase-separation in triton x-114 indicating that piplc converted the enzyme from an am ...19901965942
models for the structure and function of the bacillus thuringiensis delta-endotoxins determined by compilational analysis.the protein delta-endotoxins of bacillus thuringiensis are a commercially and environmentally important class of highly specific insecticides. from an alignment of their sequences, certain structural and functional domains can be inferred which may shed light on the mode of action of these toxins.19901966871
purification of the temperature-specific surface antigen of paramecium primaurelia with its glycosyl-phosphatidylinositol membrane anchor.the membrane form of the temperature-specific g surface antigen of paramecium primaurelia strain 156 has been purified by a novel procedure utilizing solubilization by detergent, ammonium sulfate precipitation, and high-performance liquid chromatography. the surface antigen, which was prepared in a nondenatured state containing a glycosyl-phosphatidylinositol membrane anchor, migrated as a single band upon electrophoresis in sodium dodecyl sulfate-polyacrylamide gels. following cleavage of the p ...19901967078
characterization of the parasporal inclusion of bacillus thuringiensis subsp. kyushuensis.electron microscopy of bacillus thuringiensis subsp. kyushuensis revealed that the parasporal inclusions are composed of a homogeneous center surrounded by a thick, electron-dense coating. antibodies directed against the 135- and 65-kilodalton b. thuringiensis subsp. israelensis peptides cross-reacted with the 70- and 26-kilodalton peptides, respectively, of b. thuringiensis subsp. kyushuensis.19901967173
comparison of development of bacillus thuringiensis subsp. israelensis and bacillus sphaericus in mosquito larvae.immunofluorescent staining was used with thin sections of paraffin-embedded specimens to detect the development of bacillus thuringiensis var. israelensis and bacillus sphaericus in the gut of mosquito larvae. the third- and fourth-instar larvae of aedes aegypti, anopheles maculatus, and culex quinquefasciatus were fed either vegetative cells or spores of the bacteria. spore germination, multiplication, and sporulation were studied in the larvae of each species. the spores of b. thuringiensis va ...19901969455
development of mutants of the mosquitocidal bacterium bacillus thuringiensis subspecies morrisoni (pg-14) toxic to lepidopterous or dipterous insects.the parasporal body of the mosquitocidal isolate (pg-14) of bacillus thuringiensis subsp. morrisoni (btm) contains five major proteins with molecular masses of, respectively, 27.3, 65, 128, 135, and 144 kda. proteins corresponding in mass to the first four of these also occur in the mosquitocidal strain, b. thuringiensis subsp. israelensis (bti), and it is thought therefore that the mosquitocidal activity of both strains is due to these four proteins. in other studies it has been shown that each ...19901969828
efficacy of various bacillus thuringiensis var. israelensis formulations against psorophora columbiae larvae as assessed in small rice plots, 1984-88.granular, liquid and briquette formulations of bacillus thuringiensis var. israelensis were tested in small rice plots during 1984-88 against psorophora columbiae larvae. vectobac as, skeetal g, teknar hpd, abg 6172, abg 6188, abg 6193, abg 6197, abg 6199, abg 6138f and abg 6221 provided excellent control at high dosages and good control (generally greater than 85%) at relatively low concentrations. abg 6221 and abg 6172 provided excellent control at low concentrations. additional testing of the ...19901969931
[clostridium bifermentans serovar malaysia, a new anaerobic bacterium pathogen to mosquito and blackfly larvae].a strain of clostridium bifermentans individualized as serovar malaysia (c.b.m.) according to its specific h antigen is toxic to mosquito and blackfly larvae when given orally. the toxicity occurs in sporulated cells which contain, in addition to spores, proteinic parasporal inclusion bodies and feather-like appendages; the amino acid content of the inclusion bodies is similar to that of bacillus thuringiensis serovar israelensis (b.t.i.) and b. sphaericus crystals. the toxicity to anopheles ste ...19901972899
evaluation of bactimos wettable powder, granules and briquets against mosquito larvae in malaysia.there was high mortality in late larval instars of aedes albopictus (skuse) from laboratory and field populations in the 24 h after application of three bactimos formulations of bacillus thuringiensis h-14. mortalities were higher and residual effects longer in field populations than in laboratory ones. briquets were the most effective formulation (mortality 96-100% after five weeks; 76-92% after eight weeks). culex quinquefasciatus say larvae were tested only against the briquet formulation. in ...19901973019
relative potency of bacillus thuringiensis var. israelensis and bacillus sphaericus 2362 for mansonia titillans and mansonia dyari.bacillus thuringiensis var. israelensis (b.t.i.), hd-968-s-1983, and a primary powder of bacillus sphaericus 2362 were assayed against mansonia titillans and ma. dyari. the susceptibility of the 2 species to the individual bacterial toxins was similar. the b.t.i. lc50 values were 50.5 micrograms/liter for ma. dyari and 54.7 micrograms/liter for ma. titillans; the b. sphaericus lc50 values were 339.0 micrograms/liter and 347.2 micrograms/liter, respectively. the log dose-probit mortality lines we ...19901973452
the medical importance of riceland mosquitoes and their control using alternatives to chemical insecticides.the medical importance, ecology and control of riceland mosquitoes using alternative strategies is reviewed. over 135 pest and vector anopheline and culicine mosquito species found in association with riceland habitats and their medical importance are presented. malaria and japanese encephalitis are the two most serious human diseases transmitted by riceland mosquitoes, but they have been incriminated as vectors of dozens of arboviruses and other parasites and pathogens including the causal agen ...19901973949
function of the hydrophobic transmembrane portion of thy-1 antigen.thy-1 antigen is anchored in the cell membrane by glycophosphatidyl inositol linkages instead of hydrophobic protein domains. the hydrophobic portion of thy-1 antigen is cleaved by putative "transamidase." mutated genes were constructed by using site-directed mutagenesis. one mutant gene codes thy-1 antigen lacking carboxy terminal amino acids from 112cys to 143leu including cell membrane binding amino acid 112cys. the other mutant gene codes thy-1 antigen lacking from 124trp to 143leu that incl ...19901975422
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