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[sanitary microbiological standards for bac. thuringiensis, a producer of bacterial insecticides, in plant products].survival of bac. thuringiensis, producers of bacterial insecticides in plant products, was studied in the process of culinary and technological treatment (thermal treatment, preservation, etc.), depending on the extent of dissemination of plant raw material, type of the plant product and pattern of culinary treatment. a study was also made of the viability of the above species in finished products and dishes exposed to varying storage temperatures. according to the data obtained, the use of plan ...19807405137
a comparison of protein crystal subunit sizes in bacillus thuringiensis.we have employed gel electrophoresis to determine the number and size of the subunits present in the protein crystals from 16 strains of baccillus thuringiensis. the calculated molecular weights (mw) fell into three major categories whose crystals exhibited the following protein banding patterns: type i, high mw only (140 000- 160 000); type ii, both high mw and medium mw (60 000 and 150 000); and type iii, low mw only (40 000 - 50 000). interestingly, the type i and type ii crystals were the ex ...19807459713
purification and properties of phosphatidylinositol-specific phospholipase c of bacillus thuringiensis.a phosphatidylinositol-specific phospholipase c was purified from the culture broth of bacillus thuringiensis to a homogeneous state as indicated by polyacrylamide gel electrophoresis. specific activity of purified enzyme was 312 units/mg, and the recovery of the enzyme activity was 27.2%. the purified enzyme (molecular weight: 23 000 +/- 1000) was maximally active at ph 7.5 and not influenced by edta. the enzyme specifically hydrolyzed phosphatidylinositol, but did not act on phosphatidylcholin ...19807417468
incorporation of specific fatty acid precursors during spore germination and outgrowth in bacillus thuringiensis.the selective incorporation of precursors specific for individual fatty acids in germinating and outgrowing spores of bacillus thuringiensis is described. the specific precursors utilized were [c]butyrate, -isobutyrate, -valerate, and -isovalerate, which were incorporated into even-numbered normal-chain isomers, even-numbered iso-isomers, odd-numbered normal-chain acids, and odd-numbered isohomologs, respectively. this preferential incorporation by b. thuringiensis allows the terminal carbons of ...198016345590
some effects of douglas fir terpenes on certain microorganisms.the douglas fir terpene alpha-pinene was shown to inhibit the growth of a variety of bacteria and a yeast. other terpenes of the douglas fir, including limonene, camphene, and isobornyl acetate, were also inhibitory to bacillus thuringiensis. all terpenes were inhibitory at concentrations normally present in the fir needle diet of douglas fir tussock moth larvae. the presence of such terpenes in the diet of these insects was found to strongly influence the infectivity of b. thuringiensis spores ...198016345609
rocket immunoelectrophoresis of the entomocidal parasporal crystal of bacillus thuringiensis subsp. kurstaki.rocket immunoelectrophoresis was used to quantitate the soluble parasporal crystal of bacillus thuringiensis subsp. kurstaki. the method described is rapid, reliable, specific, and extremely accurate, and it can be used to measure crystal toxin in commercial microbial insecticides that contain a mixture of spores, vegetative cells, and carrier materials.198016345656
biocontrol: bacillus penetrans and related parasites of nematodes.bacillus penetrans mankau, 1975, previously described as duboscqia penetrans thorne 1940, is a candidate agent for biocontrol of nematodes. this review considers the life stages of this bacterium: vegetative growth phase, colony fragmentation, sporogenesis, soil phase, spore attachment, and penetration into larvae of root-knot nematodes. the morphology of the microthallus colonies and the unusual external features of the spore are discussed. taxonomic affinities with the actinomycetes, particula ...198019300701
toxicity of bacillus thuringiensis spo cr mutants for the european corn borer ostrinia nubilalis.inclusion bodies isolated from spo cr mutants of bacillus thuringiensis were toxic for larvae of the european corn borer. probit analysis revealed comparable toxicity between wild-type crystals (isolated from b. thuringiensis subsp. kurstaki) and crystals produced from two spore-free mutants of the same subspecies. death of the larvae was due to starvation, presumably through delta-endotoxin-induced gut paralysis. inclusion bodies pretreated with alpha-chymotrypsinogen were equally as toxic as n ...198116345839
transformation of bacillus thuringiensis protoplasts by plasmid deoxyribonucleic acid.a method has been developed to transform plasmid deoxyribonucleic acid into protoplasts of the insect pathogen bacillus thuringiensis. protoplasts were formed by treatment of cells with lysozyme. the efficiency of formation of protoplasts was affected by the strain, the media, and the cell density. deoxyribonucleic acid uptake was induced by polyethylene glycol. deoxyribonucleic acid from the staphylococcus aureus plasmid pc194 was used for transformation. although this plasmid could not be isol ...19817462165
comparative biochemistry of entomocidal parasporal crystals of selected bacillus thuringiensis strains.parasporal crystals of bacillus thuringiensis subspp. kurstaki, tolworthi, alesti, berliner, and israelensis were compared by electron microscopy, polyacrylamide gel electrophoresis, amino acid analysis, tryptic peptide mapping, immunological analysis, and insecticidal activity. spore coats also were compared by polyacrylamide gel electrophoresis. b. thuringiensis subsp. israelensis crystals were lethally toxic to mosquito larvae and nontoxic to tobacco hornworm larvae. conversely, crystals from ...19817462158
[toxicity of bacillus thuringiensis var. israelensis serotype hi4, for larvae of sandflies, the leishmaniasis vectors (author's transl)]. 19817318051
occurrence of resistance to neomycin and kanamycin in bacillus popilliae and certain serotypes of bacillus thuringiensis: mutation potential in sensitive strains. 19817240780
correlation between specific plasmids and delta-endotoxin production in bacillus thuringiensis. 19817267811
[bactericidal activity of the dye erio acid red xb 400 towards bacillus thuringiensis].laboratory and field tests revealed that the addition of erio acid red xb 400 dye (ear) to bacillus thuringiensis formulations inhibited spores of the bacillus. in the laboratory, 74% of the spores present in a suspension containing 16 x 10(9) viable spores/ml, and 0.25 gm/l of ear, were inhibited after 28 h. spore inactivation in a physiological solution containing 1 x 10(7) viable spores/ml was 75% after the same period of exposure to the same ear concentration. field tests showed a reduction ...19817306883
[biological insecticides: new weapons against the transmission of disease by vectors]. 19816458310
purification and characterization of the entomocidal protoxin of bacillus thuringiensis.a procedure for purifying the insecticidal parasporal protoxin of bacillus thuringiensis and a description of its biochemical and biophysical properties is provided. mild alkali titration was necessary to generate a functional protoxin in a soluble form, and anion-exchange chromatography was used to remove contaminating cytoplasmic proteases that are nonspecifically bound to whole native parasporal crystals. polyacrylamide gel electrophoresis, gel filtration chromatography, and meniscus depletio ...19817204384
transformation of bacillus thuringiensis subsp. galleria protoplasts by plasmid pbc16.protoplasts of the entomopathogenic bacterium bacillus thuringiensis subsp. galleria were transformed by plasmid pbc16. the frequency of transformation was much lower than that of bacillus subtilis. all isolated b. thuringiensis transformants were characterized by increased sensitivity to lysozyme as compared with the original strain.19817217007
cloning and expression of the bacillus thuringiensis crystal protein gene in escherichia coli.sau 3a1 partial digestion fragments from bacillus thuringiensis var. kurstaki hd-1 plasmid dna were ligated into the bamhi site of the cloning vector pbr322 and transformed into escherichia coli strain hb101. colonies presumed to contain recombinant plasmids were screened for production of an antigen that would react with antibody made against b. thuringiensis crystals. one strain, es12, was isolated by using this procedure. es12 contains a plasmid of mr 11 x 10(6) that has dna sequence homology ...19817019914
[bacillus thuringiensis bacteriophage interference].strains of bacillus thuringiensis lysogenic for temperate bacteriophage tm2 inhibit the development of virulent bacteriophage tg4, although the latter can absorb to and kill these bacteria. tm2 mediated interference did not act directly on the tg4 genome; rather, the phage altered the host physiology. the latent period of tg4 growth in bac. thuringiensis lysogenic for phage tm2 was longer than when nonlysogenic bacteria were infected. progeny yields have been counted in bac. thuringiensis strain ...19817198072
[specificity and active principle of bacillus thuringiensis var. israelensis].bio-assays of b. thuringiensis var. israelensis on larvae of drosophila melanogaster, musca domestica, culicoides sp. and chironomus plumosus are negative except in the last case, but only with doses much higher than those which are lethal for mosquito larvae. tests on mollusks (biomphalaria glabrata) and golden fishes are also negative. the specificity of action of the h 14 serotype, limited to a few diptera families, should be mainly related to the special characteristics of its crystals, whic ...19817249246
bacillus thuringiensis distribution in soils of the united states.during a 2-year study, samples of various types of soils were collected from 115 fields that had not previously been tested with bacillus thuringiensis and which were remote from any large-scale aggregations of lepidopterous insects in rearing or grain-storage areas. an average of about 400 isolates were examined from each soil, and, of 46 373 isolates examined, only 250 (0.5%) were identified as b. thuringiensis. while it was almost impossible to insure that a field had never been treated with ...19817306875
[sensitization and hyposensitization to bac. thuringiensis]. 19817308791
relative activity of bacillus thuringiensis var. kurstaki and b. thuringiensis var. israelensis against larvae of aedes aegypti, culex quinquefasciatus, trichoplusia ni, heliothis zea, and heliothis virescens. 19817320315
[experiments to inactivate the entomopathogenic action of the preparation dipel in the silkworm bombyx mori l].experiments were carried out at the vivarium of the silkworm experimental station in vratsa during the autumn silkworm feeding in 1980, using the kinshu x showa hybrid. tested was its tolerance of a water solution of chlorinated lime with active chlorine from 0.003 to 1.0 per cent administered orally with the feed. studied was at the same time the inactivating capacity of these chlorine solutions with regard to 0.3 per cent water solutions of dipel in less than a minute's time, the latter being ...19817324378
isolation of a protein from the parasporal crystal of bacillus thuringiensis var. kurstaki toxic to the mosquito larva, aedes taeniorhynchus. 19817332548
a new subfamily of microbial serine proteinase? structural similarities of bacillus thuringiensis and thermoactinomyces vulgaris extracellular serine proteinases. 19817028036
[extracellular serine proteinase of bacillus thuringiensis].pure extracellular serine proteinase has been isolated from a broth filtrate of bacillus thuringiensis, strain 69-6r by fractionation with ammonium sulfate and affinity chromatography on sepharose 4b derivatives containing p-(omega-aminomethyl)-phenylboronic acid and cyclopeptide bacillichin as ligands. the enzyme is completely inactivated by phenylmethylsolfonyl fluoride, a specific reagent for serine proteinases, has the molecular weight of 29 000 and pi of 8.4, reveals maximal activity and st ...19817028140
[cloning and the expression of the dna promotor fragments of bacillus thuringiensis in escherichia coli cells].the promoter-containing fragments of bacillus thuringiensis subsp. galleria 69-6 dna have been cloned on the pga24 vector in escherichia coli cells. the recombinant plasmids make cells resistant to tetracycline in a wide range. the level of tetracycline-resistance does not depend on the length of a foreign insertion. new polypeptides are synthesized on the template of the recombinant plasmids in vitro. the data point out the presence in bac. thuringiensis dna of many genes which are able to expr ...19817033045
[detection of thermolabile exotoxin in b. thuringiensis and its separation from phospholipase c]. 19817315023
[ph variations in the midgut of aedes aegypti in relation to bacillus thuringiensis var. israelensis (serotype h14) crystal intoxication].after feeding aedes aegypti larvae with b. thuringiensis var. israelensis crystals the very alkaline ph (greater than or equal to 10) of the anterior midgut remains stable during the first twenty minutes, in spite of important cytological damage. thereafter, the ph drops to surround the neutrality and the death occurs. these results are discussed according to the knowledge on the action of b. thuringiensis var. israelensis.19817296735
[innocuousness of bacillus thuringiensis var. israelensis for the larvae of oysters]. 19817296737
progress in malaria vector control.malaria control, except in tropical africa, will probably continue to be based to a large extent on the use of insecticides for many years. however, the development of resistance to insecticides in the vectors has caused serious difficulties and it is necessary to change the strategy of insecticide use to maximize their efficacy. a thorough knowledge of the ecology and behaviour of each vector species is required before the control strategy can be adapted to different epidemiological situations. ...19816976842
[use of the supernatant from cultures of bacillus thuringiensis in an in vivo study of the functioning of the nucleolar organizer in drosophila melanogaster].the use of drosophila melanogaster mutants deficient in active ribosomal genes, allowed us to demonstrate that the in vivo degree of resistance to a given concentration of supernatant from bacillus thuringiensis cultures, can be an indication of the ribosomal genes functional level.19816796208
[isolation and characteristics of radioresistant bacillus subtilis and bacillus thuringiensis mutants]. 19816796992
[instability of the auxotrophic markers in bacillus thuringiensis].auxotrophic mutants of bacillus thuringiensis have been isolated and compared with the mutants of bacillus subtilis. it has been found that after spore formation and a prolonged storage, the considerable part of cells in a population of some strains display a genetically unstable additional requirement for arginine with high frequency. the correlation between tetracycline sensitivity and unstable requirement for arginine and other growth factors has been found. the possible reasons for instabili ...19816797872
mammalian safety of microbial agents for vector control: a who memorandum.this memorandum outlines recommended safety tests for application to biological agents under consideration for widespread use for pest control. the basic principles utilized in developing these recommendations were that: (i) the hazards presented by microbial pesticides are inherently different from those associated with chemical pesticides and the tests used to determine hazard potential to man should reflect this; (ii) a high proportion of negative results is likely; (iii) tiered testing syste ...19816978192
the entomocidal toxins of bacillus thuringiensis. 19817025037
[cytologic alterations induced in bacillus thuringiensis (berliner) by zearalenone].zearalenone (f-2 toxin) an estrogenic mycotoxin secreted by some species of fusarium exhibits an antibacterial activity which can be easily demonstrated in gram-positive spore forming bacteria, especially in bacillus sp. morphologically abnormal cells were produced by bacillus thuringiensis (berliner) in response to zearalenone. the most significant ultrastructural alterations obtained with the mycotoxin at 2.5 or 5.0 micrograms/ml, are: increase of number of mesosomes which are hypertrophied, d ...19816454078
[results of laboratory trials of bac. thuringiensis berliner preparations on the larvae of blood sucking mosquitoes in the family culicidae. i]. 19826121285
the action of two formulations containing bacillus thuringiensis (serotype h-14) on some autochthonous mosquito species (diptera : culicidae). 19826126174
effect of bacillus thuringiensis var. israelensis on some egyptian mosquito larvae. 19826130117
transfer of bacillus thuringiensis plasmids coding for delta-endotoxin among strains of b. thuringiensis and b. cereus.the recently discovered high-frequency transfer of plasmids between strains of bacillus thuringiensis was used to study the genetic relationship between plasmids and production of the insecticidal delta-endotoxin crystal. three strains of b. thuringiensis transmitted the cry+ (crystal-producing) phenotype to cry- (acrystalliferous) b. thuringiensis recipients. agarose gel electrophoresis showed that one specific plasmid from each donor strain was always present in cry+ "transcipients." the size ...19826294667
role of the parasporal body in causing toxicity of bacillus thuringiensis toward aedes aegypti larvae. 19826120198
[joint action of bacterial preparations and insect growth regulators on the larvae of blood-sucking mosquitoes]. 19826127605
the effect of bacillus thuringiensis var. israelensis on toxorhynchites rutilus rutilus (diptera: culicidae) in the presence and absence of prey. 19826128423
comparative bioassays of bacillus thuringiensis h-14 formulations against four species of mosquitoes in malaysia.comparative laboratory bioassays of three formulations of bacillus thuringiensis h-14 (ips-78, san 402-i and bactimos) were conducted against late 3rd/early 4th instar larvae of four species of mosquito, viz., aedes aegypti, culex quinquefasciatus, anopheles balabacensis and mansonia (mansonioides) indiana, in malaysia. from the average response of the mosquito larvae to the three formulations of b. thuringiensis h-14, ae. aegypti was found to be most susceptible, followed by cx. quinquefasciatu ...19826128794
field evaluation of the microbial insecticide bacillus thuringiensis serotype h-14 against floodwater mosquitoes.four experimental formulations of the microbial insecticide bacillus thuringiensis var. israelensis (serotype h-14) were evaluated in the field against larvae of the floodwater mosquitoes aedes nigromaculis and psorophora columbiae with ground and aerial application methods. the formulations included abg-6108d (abbott laboratories, north chicago, ill.), a wettable powder containing about 400 iu/mg, sandoz 402-wdc (sadoz, inc., homestead, fla.), a flowable concentrate containing 600 iu/mg, and tw ...19826125127
[study of the larvicidal activity of bacillus thuringiensis var. israelensis on toxorhynchitinae larvae (author's transl)].toxicity of bacillus thuringiensis var. israelensis, h 14 serotype, has been tested on larvae of toxorhynchites amboinensis, predaceous larvae of other culicinae larvae. the toxorhynchites larvae are not sensitive to the bacterial toxin up to relatively high dosages, except when larvae of aedes aegypti are provided in the suspension. mode of action of the crystal appears to be similar to the one observed in the epithelial cells of intoxicated aedes aegypti larvae midgut.19826125271
[effect of different carbon and purine nucleotide sources on exoprotease synthesis by bacillus thuringiensis].bacillus thuringiensis cells, depending on their physiological state, produce different quantities of exoprotease. easily metabolizable carbon sources in the medium can affect the process in the opposite way: they inhibit synthesis of the enzyme by the cells in the exponential growth phase, and stimulate it by the sporulating cells. apparently, camp is not an effector of catabolite repression regulating exoprotease synthesis by the cells in the exponential growth phase, inspite of stimulating th ...19827040922
[exoprotease synthesis, insecticidal activity and spore formation in a bacillus thuringiensis mutant defective in glucose transport]. 19826759887
enzyme-linked immunosorbent assays for detection and quantitation of the entomocidal parasporal crystalline protein of bacillus thuringiensis subspp. kurstaki and israelensis.an enzyme-linked immunosorbent assay was used to detect and quantitate the parasporal crystal toxins of bacillus thuringiensis subspp. kurstaki and israelensis. the assay method described is extremely sensitive, accurate, and highly specific. with this technique, crystalline insecticidal proteins from several subspecies of b. thuringiensis were compared. the dipteran crystal toxin produced by b. thuringiensis subsp. israelensis was shown to share few epitopes with the lepidopteran toxin from b. ...19827081987
relationship of the syntheses of spore coat protein and parasporal crystal protein in bacillus thuringiensis.two major classes of polypeptides were extracted from the spore surface of bacillus thuringiensis subsp. kurstaki: the 134,000-dalton protoxin that is the major component of the crystalline inclusion and spore coat polypeptides very similar to those found on bacillus cereus spores. the quantity of spore coat polypeptides produced was reduced when compared with that produced by certain acrystalliferous mutants or by b. thuringiensis subsp. israelensis. the latter organism produced an inclusion to ...19827085565
interchangeability of delta subunits of rna polymerase from different species of the genus bacillus.rna polymerase was purified from five species of bacillus, including bacillus subtilis. each polymerase had a subunit composition analogous to that reported for b. subtilis, i.e., beta beta '2 alpha sigma delta omega 1 omega 2. the delta subunits from the b. subtilis and bacillus thuringiensis polymerases were interchangeable, as judged from their effects on promoter selection in the polymerase binding assay.19826802805
[plasmid transformation of bacillus thuringiensis protoplasts]. 19826800747
[enterobacterial gene expression of antibiotic resistance under the control of bacillus thuringiensis regulatory signals in gram-negative and gram-positive bacteria].two recombinant plasmids ppbt9 and ppbt74 carrying hindiii promoter-active dna fragments of bacillus thuringiensis onto the vector pga24 were studied. the cloned fragment of ppbt9 plasmid has many homologous regions in bac. thuringiensis genome. this fragment contains three escherichia coli rna polymerase binding sites, one of which is responsible for promoting tetracycline resistance of the promoter-deficient enterobacterial tet gene in e. coli cells. the bacillar fragment of ppbt74 plasmid has ...19826818110
effect of strain and medium variation on mosquito toxin production by bacillus thuringiensis var. israelensis.the effect of strain variation and culture medium on production of toxin lethal to mosquito larvae by bacillus thuringiensis var. israelensis serotype h-14 was investigated. shake flask culture of b. thuringiensis h-14 strains showed varied ability to produce toxins lethal to mosquito larvae dependent upon the particular strain and growth medium used. buffered media demonstrated no better mosquito toxicity than did unbuffered media that ranged in ph from 5.7 to 8.1 at harvest. although toxin pro ...19827139413
laboratory evaluation of bacillus thuringiensis var. israelensis serotype h-14 against mosquito larvae with particular reference to aedes aegypti. 19827153478
activity of a "thermostable exotoxin" of bacillus thuringiensis subsp. morrisoni in the salmonella/microsomal assay for bacterial mutagenicity. 19827153535
[study of sporulation of the bacterium bac. thuringiensis apropos of its infection by phages, using the method of mathematical planning of experiments]. 19827168255
molecular relationships among plasmids of bacillus thuringiensis: conserved sequences through 11 crystalliferous strains.screening for the plasmid content of 11 strains belonging to nine different serotypes of b. thuringiensis was carried out by electron microscopic examination and electrophoresis in agarose gels. all the strains contained at lest two covalently closed, circular (ccc) dna species. in one strain (berliner 1715), 17 extrachromosomal elements could be distinguished with regard to their size, ranging from 3.9 to 180 mdal. southern hybridisation experiments showed that most of these plasmids fell into ...19826956789
cloning and localization of the lepidopteran protoxin gene of bacillus thuringiensis subsp. kurstaki.bacillus thuringiensis subsp. kurstaki produces a proteinaceous crystalline inclusion that is toxic for lepidopteran larvae. there are several size classes of plasmids in this organism and the presence of one or more has been correlated with production of this protein, defined as a protoxin. dna fragments of b. thuringiensis subsp. kurstaki, obtained by ecori digestion, were cloned into the vector charon 4a. recombinant phage were screened immunologically for the production of protoxin. cells in ...19826310560
cloning and expression of the crystal protein genes from bacillus thuringiensis strain berliner 1715.from a clone bank of the entire genome of bacillus thuringiensis, one clone that contains a plasmid ( pbt 15-88) harboring a sporulation gene was identified by molecular hybridization. this gene, identified as the crystal protein gene, occurs both on a large host plasmid dna and in the chromosomal dna in b. thuringiensis strain berliner 1715. the inserted sequence of pbt 15-88, which corresponds to the chromosomal sequence, was not expressed in escherichia coli. in b. thuringiensis (kurstaki), t ...19826329704
[distribution, homology and cloning of cryptic bacillus thuringiensis plasmids].the 69-6 strain of bacillus thuringiensis subsp. galleriae harbours at least 7 cryptic plasmids (pbtg1 - pbtg7) with molecular lengths 8,4 to 15,7 kb. according to hybridization analysis, the plasmid pbtg2 (8,7 kb) and other plasmids of the same host strain as well as cryptic plasmids of the strains belonging to 10 other serotypes of bac. thuringiensis share detectable homology. as shown by the data of heteroduplex analysis, about 60% of pbtg1 and pbtg2 genomes have homologous dna sequences. the ...19827037539
[electron microscope study of "bacillus thuringiensis" var. "israelensis" sporulation and crystal biogenesis (author's transl)].the sporulation and crystal development of bacillus thuringiensis serotype h-14 was described for a wild spore- and crystal-forming strain and for a mutant crystal but non spore-forming strain. the special nature of the israelensis var. consisted in the composite structure of the crystal, made of a number of components differing in size, shape and electron density. the components were formed in a single inclusion or sometimes separately inside the same bacterial cell.19827103310
[participation of bacillus thuringiensis plasmids in the synthesis of an insecticidal delta-endotoxin]. 19827105967
large river treatment with bacillus thuringiensis (h-14) for the control of simulium damnosum s.l. in the onchocerciasis control programme.complete mortality of simulium damnosum theobald s.l. larvae was obtained along a 19 km stretch of the marahoué river including and downstream of the danangoro rapids complex in the bandama basin of ivory coast after treatment with 1.5 ppm/10 min of the sandoz 402-1-wdc formulation of bacillus thuringiensis berliner serotype h-14. partial control was observed for an additional 15 km. the level of control was especially encouraging considering the low concentration (.8%) of active ingredient in t ...19827112688
ultrastructural analysis of membrane development during bacillus thuringiensis sporulation. 19827077740
[antibiotic sensitivity of bacillus thuringiensis var. galleriae strains].bacillus thuringiensis strains forming colonies of the s and r morphology were found to be susceptible to streptomycin, chloramphenicol, rifampicin, neomycin, lincomycin, monomycin, kanamycin, and resistant to ampicillin and polymyxin. the s strains were shown to be susceptible to tetracycline (tets), whereas the r strains were either susceptible (tets) or resistant (tetr). the population of tetr strains was heterogeneous in its resistance to tetracycline (the frequency of tetr cells was from 10 ...19827121329
[effect of physicochemical factors on bacillus thuringiensis sporulation].spore germination was studied in bacillus thuringiensis subsp. galleriae. optimal temperature regimes were selected for spore activation and initiation. the formation of spores and the rate of their subsequent germination were shown to depend on the composition of growth media in which the organism was cultivated. the paper describes changes in the fine structure of spores at different stages of their germination.19827144612
[differences in primary structures of delta-endotoxins produced by various serotypes of bacillus thuringiensis].the primary structures of delta-endotoxins (crystal-forming proteins) produced by two serotypes of bacillus thuringiensis--v (var. galleriae) and iii (var. alesti) were compared. these proteins differ by the specificity of their action on lepidoptera larvae as well as by their molecular weights. to evaluate the homology of primary structures the tryptic hydrolysates of both endotoxins were fractionated by ion-exchange and thin-layer cellulose chromatography with a subsequent amino acid determina ...19827138972
[initiators and inhibitors of spore germination of bacillus thuringiensis]. 19827176973
purification of poly-beta-hydroxybutyrate by density gradient centrifugation in sodium bromide.fractionation of fully sporulated cultures of bacillus thuringiensis by density gradient centrifugation in nabr produced two bands which were identified as poly-beta-hydroxybutyrate. this technique generated high yields of membrane-bound and unbound granules of exceptional purity and degree of polymerization.198216346018
asporogenous bacillus thuringiensis mutant producing high yields of delta-endotoxin.an asporogenous bacillus thuringiensis subsp. kurstaki strain ik mutant, strain 290-1, which produced high yields of delta-endotoxin, was obtained by ethyl methane sulfonate treatment of a spore suspension. the mutant strain produced about the same amount of delta-endotoxin as that produced by the parent strain, but 10 to 10 cells did not form any detectable dormant spores.198216346044
formation of crystalline delta-endotoxin or poly-beta-hydroxybutyric acid granules by asporogenous mutants of bacillus thuringiensis.parental strains and asporogenous mutants of bacillus thuringiensis subspp. kurstaki and aizawai produced high yields of delta-endotoxin on m medium, which contained 330 mug of potassium per ml, but not on st and st-a media, each of which contained only 11 mug of potassium per ml. on st and st-a media, refractile granules were formed instead. these granules had no insecticidal activity against silkworms and were isolated and identified as poly-beta-hydroxybutyric acid. supplementation of the pot ...198216346040
enzyme-linked immunosorbent assay for quantitative detection of bacillus thuringiensis crystal protein.accurate measurement of the toxic protein crystal produced during deep-tank fermentation of bacillus thuringiensis is critical for optimum process yield. the currently accepted method is a bioassay that requires more time to generate data than to complete the fermentation itself. a noncompetitive enzyme-linked immunosorbent assay has been developed with purified b. thuringiensis crystals to generate rabbit antiserum. this technique gives a quantitative crystal protein value with a colorimetric e ...198316346207
dissolution and degradation of bacillus thuringiensis delta-endotoxin by gut juice protease of the silkworm bombyx mori.the dissolution and degradation of dagger-endotoxin (crystal) of bacillus thuringiensis subsp. kurstaki strain hd-1 were investigated. crystals were dissolved in 0.1 m phosphate-carbonate-naoh buffer at ph > 12. swelling of crystals occurred in the buffer between ph 10 and 11, and crystals dissolved in the same buffer supplemented with gut juice protease of the silkworm bombyx mori. the proteolytic dissolution of crystals occurred after a time lag of several minutes in 0.1 m carbonate-naoh buffe ...198316346206
complete purification of phosphatidylinositol-specific phospholipase c from a strain of bacillus thuringiensis.a phosphatidylinositol-specific phospholipase c was purified from the culture broth of bacillus thuringiensis iam 12077 to a homogeneous state as revealed by polyacrylamide gel electrophoresis. the specific activity of the purified enzyme was 559 units/mg and recovery of the enzyme activity was 31%. molecular and physiological properties of the purified enzyme, including molecular weight (22,000), isoelectric point (pi = 4.9) and its ectoenzyme-releasing activity, were studied in comparison with ...19836885748
[activity of intracellular enzymes in bacillus thuringiensis prospores and sporangia].the activity of endocellular enzymes (alkaline phosphatase, protease, glucose dehydrogenase, aldolase, malate dehydrogenase, nadh dehydrogenase, nadh oxidase) was studied in isolated prospores and sporangia as well as in vegetative cells of bacillus thuringiensis strains, one of which produced crystals and one did not. the activity of malate dehydrogenase and nadh dehydrogenase was high in prospores of the both strains at the fifth and sixth stages of spore formation. the strain which did not pr ...19836341786
[pathogenesis of bacillus thuringiensis var. israelensis in killing larva of mosquitoes and its application]. 19836675863
two types of entomocidal toxins in the parasporal crystals of bacillus thuringiensis kurstaki.two types of entomocidal proteins of bacillus thuringiensis kurstaki were isolated from the parasporal bodies (crystals), and their structures were compared with each other in relation to the toxic activity. when the crystals were dissociated in 2% 2-mercaptoethanol at ph 10, a protein of mr = 135,000, called delta-endotoxin, was liberated. the crystals of a strain of b. thuringiensis kurstaki, the hd-1 strain, also released another protein in small quantities. this minor component of hd-1, whic ...19836357098
[effect of proteins on exoprotease synthesis by bacillus thuringiensis].bacillus thuringiensis was shown to grow better in media with albumin, gelatin and casein than in a chemically defined medium; proteins did not induce the synthesis of exoprotease. two maxima were found in the enzyme synthesis: the first one at the exponential phase of the cultural growth, and the second one during spore formation by the culture. the synthesis at the exponential growth phase was susceptible to nitrogen metabolite repression while the synthesis of exoprotease at the stationary ph ...19836358805
potassium ion transport atpase in insect epithelia.k+ transport by the epithelia of midgut, salivary glands, malpighian tubules, sensory sensilla, possibly rectum, and other organs of certain insects appears to use a unique k+ atpase. ouabain inhibition of transport-related events has not been demonstrated in these epithelia. the k+ pump is unlike the na-k;ump but resembles the h;ump of phosphorylating membranes in its transport orientation, efficient thermodynamics, speculated two k+ per one mgatp2- stoichiometry, electrogenicity, and structure ...19836317792
utilization of fodder yeast and agro-industrial by-products in production of spores and biologically - active endotoxins from bacillus thuringiensis.a number of newly-devised fermentation media were evaluated with respect to their ability to support sporulation and biosynthesis of endotoxins by strains of bacillus thuringiensis that are biologically active against spodoptera littoralis, heliothis armigera, and spodoptera exigua. fodder yeast from dried cells of saccharomyces cerevisiae could be used as a complete mono-component medium for production of highly active spore-delta-endotoxin complexes from b. thur., vars. entomocidus, kurstaki a ...19836666415
[effect of gramicidin d on the exoprotease activity of bacillus thuringiensis].a treatment of bacillus thuringiensis cells with gramicidine d in the medium containing the yeast and polysaccharides increases the lag-phase up to 12 h without a change of the rate during the logarithmic phase of the culture growth. the exoprotease activity of cells treated with gramicidine reaches a maximum value 4 h earlier in comparison with the control culture, and the activity level is increased 2-fold. at a concentration increasing the exoprotease activity, gramicidine was found to induce ...19836196773
[current problems of developing biological methods for controlling the vectors of human parasitic diseases]. 19836143243
[experiments with bacillus thuringiensis protoplasts. ii. study of the potential interspecies fusion of bacterial protoplasts: bacillus thuringiensis and bacillus megaterium].in the present study the possibility of obtaining interspecific bacterial hybrids by polyethylene glycol-assisted fusion of protoplasts from bacillus thuringiensis and bac. megaterium has been examined. electron microscopic and genetic data allow to confirm with great probability that cytological fusion takes place. however, genetic analysis revealed that neither of methods applied for protoplast fusion gave stable recombinants. apparently, it is due to the lack of recombination or the death of ...19836407894
isolation of a dna sequence related to several plasmids from bacillus thuringiensis after a mating involving the streptococcus faecalis plasmid pam beta 1.the transmissible plasmid pam beta 1, which codes for resistance to erythromycin and lincomycin, was transferred from streptococcus faecalis to several strains of bacillus thuringiensis by a filter-mating process. introduction of pam beta 1 into the emr transconjugant strains of b. thuringiensis was confirmed by southern hybridisation using the 32p-labelled pam beta 1 as a probe. in the b. thuringiensis transconjugant strains, used as donors, the beta plasmid conserved its ability to be transfer ...19836413823
some considerations on the safety evaluation of nonviral microbial pesticides.the tactics and rationale of maximum challenge safety tests for nonviral microbial pesticides have been reviewed. maximum challenge tests and a tier approach to data collection for regulatory purposes offer the best opportunities to detect the acute effects of entomopathogenic organisms in mammals. premature condemnation of promising organisms that are based on incomplete results of maximum challenge tests must be avoided. further investigations should be conducted on the role of mammalian immun ...19836601535
[synthetic medium for cultivating bacillus thuringiensis].bacillus thuringiensis subsp. galleriae 69/6 was cultivated in a synthetic medium containing 5 amino acids and nicotinic acid. the dynamics of the culture growth and amino acid assimilation were studied in this medium and in a medium containing yeast extract. the phase of spore germination increased, the yield decreased and the maximal growth rate became higher when the culture grew in the synthetic medium. the percentage of thermoresistant spores was slightly lower in the synthetic medium compa ...19836645997
larvicidal activity of bacillus thuringiensis subsp. israelensis, serovar h14 in aedes aegypti: histopathological studies. 19836841993
[action on flea imagoes of bacterial preparations of the thuringiensis-group and their fillers]. 19836843497
[effect of the larval density of aedes aegypti mosquitoes on their mortality as affected by bacillus thuringiensis berl. preparations]. 19836843501
[estimation of the spectrum of the aerial dispersion of bacillus thuringiensis].the present paper estimates the number of viable spores of bacillus thuringiensis per droplet and reveals the importance of this data to improve b. thuringiensis treatments. for a given diameter, droplets from futura formula contained two times more spores than droplets from the formulas used to date. it is preferable to have b. thuringiensis droplets larger than those of chemical insecticides. a grumman agcat aircraft calibrated to give the desired larger droplets resulted in successful b. thur ...19836661697
[action of crystals of bacillus thuringiensis var. israelensis on the midgut of aedes aegypti l. larvae, studied by electron microscopy].ingestion of bacillus thuringiensis var. israelensis crystals by aedes aegypti larvae is followed by midgut epithelium disruption. earliest ultrastructural changes consist of an enlargement of intra- and intercellular spaces in the basal region of the cell. endoplasmic reticula disintegrate by forming spherical structures which increase in size during intoxication. mitochondria are transformed at first into a condensed form, then become swollen with the disappearance of internal cristae. in the ...19836870088
toxicity of bacillus thuringiensis var. israelensis crystals to aedes aegypti larvae: carbonate reversal.the toxicity of purified bacillus thuringiensis var. israelensis crystals to larvae of aedes aegypti could be reversed 100-fold by levels of k(2)co(3) as low as 0.15%.19836870244
bacillus thuringiensis var israelensis crystal delta-endotoxin: effects on insect and mammalian cells in vitro and in vivo.bacillus thuringiensis var israelensis parasporal crystal delta-endotoxin was purified by ultracentrifugation on a discontinuous sucrose gradient. native delta-endotoxin crystals showed no detectable toxicity in the vitro and in vivo systems that are described. by contrast alkali-solubilized crystal delta-endotoxin caused rapid cytological and cytopathological changes in aedes albopictus, choristoneura fumiferana 63 cf1, spodoptera frugiperda and trichoplusia ni cell lines as observed by phase-c ...19836874728
[effect of temperature and aeration on bacillus thuringiensis growth and sporulation].the growth of bacillus thuringiensis was studied as a function of temperature and aeration. the vegetative growth, the yield of viable spores and their thermoresistance did not depend, for all practical purposes, on the rate of aeration within the range of 25 to 60 mg o2 per litre per minute. a rise of temperature from 20 to 35 degrees c doubled the titre of spores and increased their thermoresistance. when the temperature of cultivation was increased to 40 degrees c, the process of spore format ...19836664310
[the effects of bacillus thuringiensis on the greater wax moth, galleria mellonella (l.) (lepidoptera: galleriidae)].the effects of bacillus thuringiensis preparation on the greater wax moth population have been investigated under laboratory conditions. b. thuringiensis isolated from commercial insecticidal formulations such as dipelr (abbott lab. usa), tribactur btb wp (fabrick von chemische production, holland), bactospein (laboratoire roger, france). the effective strain was used in this experiment. the applied concentrations of bacillus on the greater wax moth larvae are 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 gram, ...19836669083
small scale field trials with bacillus thuringiensis variety israelensis h-14 strain against larvae of anopheline and culicine mosquitoes. 19836674325
spontaneous loss of a high molecular weight plasmid and the biocide of bacillus thuringiensis var. israeliensis. 19836838531
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