Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| safety testing of bacillus thuringiensis preparations, including thuringiensin, using the salmonella assay. | the aim of this study was to test genotoxicity aspects of the safety of two strains of bacillus thuringiensis. the strains were of serotype h-1, producing thuringiensin, toxic to flies, and serotype h-14, producing endotoxin, toxic to mosquitoes, but not thuringiensin. four preparations were tested: tenfold concentrated cell-free culture media of serotypes h-1 and h-14, prepurified thuringiensin, and purified endotoxin. no increases in revertant colony numbers of the tester strains of salmonella ... | 1995 | 7658050 |
| a glycoprotein multimer from bacillus thuringiensis sporangia: dissociation into subunits and sugar composition. | two glycoproteins (205 and 72 kda) were found in bacillus thuringiensis sporangia. they were predominantly localized in the exosporium and/or the spore coat, although a small proportion was also found in membranes. a method for the dissociation of hydrophobic aggregates that resist the usual conditions of sds-page is described. using this method we established that the 205 kda glycoprotein is a multimer of the 72 kda one. deglycosylation of the 205 kda and 72 kda glycoproteins with trifluorometh ... | 1995 | 7659076 |
| domain organization of bacillus thuringiensis cryiiia delta-endotoxin studied by denaturation in guanidine hydrochloride solutions and limited proteolysis. | denaturation of bacillus thuringiensis cryiiia delta-endotoxin--an insecticidal protein, active against coleoptera larvae--in concentrated guanidine hydrochloride solutions was pursued by fluorescence and circular dichroism spectroscopy and limited proteolysis. it was found that the protein consists of two fragments that differ by their stability to denaturation by guanidine hydrochloride at ph 3. the less stable fragment corresponds to the n-terminal alpha-helical domain limited by leu-279; the ... | 1995 | 7662112 |
| deletion mutants of the gene encoding delta-endotoxin specific to scarabaeid beetles: minimum region of the gene required to express the activity. | various deletion genes for the delta-endotoxin protein of bacillus thuringiensis strain buibui were made. the truncated proteins were produced in e. coli, and their larvicidal activity against the cupreous chafer was checked. the fifth block of the five blocks described as "conserved" was shown to be necessary for the activity. | 1995 | 7670204 |
| expression and synergistic effect of three types of crystal protein genes in bacillus thuringiensis. | bacillus thuringiensis nt0423 newly isolated from sericultural farms in korea produces quite atypical bipyramidal crystals of a common major band of ca. 130 kda, and has dual specificity against lepidoptera and diptera. to enforce the diptera toxicity of b. thuringiensis nt0423, cryivd and cyta genes were transformed into b. thuringiensis nt0423. the transformant b. thuringiensis pt0529 was obtained from introduction of pcg5 into b. thuringiensis nt0423 by electroporation. the expression of crys ... | 1995 | 7677771 |
| lepidopteran-specific crystal toxins from bacillus thuringiensis form cation- and anion-selective channels in planar lipid bilayers. | previous studies in our laboratory have shown that cryic, a lepidopteran-specific toxin from bacillus thuringiensis, triggers calcium and chloride channel activity in sf-9 cells (spodoptera frugiperda, fall armyworm). chloride currents were also observed in sf-9 membrane patches upon addition of cryic toxin to the cytoplasmic side of the membrane. in the present study the ability of activated cryic toxin to form channels was investigated in a receptor-free, artificial phospholipid membrane syste ... | 1993 | 7681482 |
| effect of promoter modification on mosquitocidal cryivb gene expression in synechococcus sp. strain pcc 7942. | the impact of promoter modification on the expression of the mosquitocidal bacillus thuringiensis subsp. israelensis cryivb gene when used to transform the cyanobacterium synechococcus sp. strain pcc 7942 has been examined. maximal transcript and protein abundances were achieved by the addition of the lacz promoter upstream of the cryivb sequence. replacement of the endogenous corresponding bacillus sequences with the synechococcus petf1 promoter, ribosome binding site, and initiation codon also ... | 1993 | 7690220 |
| characterization of an avirulent pleiotropic mutant of the insect pathogen bacillus thuringiensis: reduced expression of flagellin and phospholipases. | an avirulent pleiotropic mutant of the insect pathogen bacillus thuringiensis subsp. gelechiae, isolated by heierson et al. (a. heierson, i. sidén, a. kivaisi, and h. g. boman, j. bacteriol. 167:18-24, 1986) as a spontaneous phage-resistant mutant, was further characterized and found to lack the expression of phosphatidylcholine- and phosphatidylinositol-degrading phospholipase c, beta-lactamase, and flagellin because of the absence of corresponding mrnas. the avirulent mutant was also found to ... | 1993 | 7693592 |
| ion channel activity of n-terminal fragments from cryia(c) delta-endotoxin. | proteolytically-derived amino-terminal fragments from the bacillus thuringiensis delta-endotoxin, cryia(c), demonstrated ion channel activity in two in vitro assays in the absence of any membrane receptors. a 24.5 kda fragment (from spodoptera frugiperda digestive proteolysis) formed cation-selective channels (10mv for a 3:1 salt gradient) in planar lipid bilayers up to several hundred picosiemen conductance. a 21.5 kda fragment doublet (from alkaline hydrolysis) also showed large conductance in ... | 1993 | 7694582 |
| production of multiple delta-endotoxins by bacillus thuringiensis: delta-endotoxins produced by strains of the subspecies galleriae and wuhanensis. | a method was developed to assess the number of delta-endotoxins contained in bacillus thuringiensis entomocidal crystals. it utilized proteolytic conversion of 130-kda protoxin into 60- to 65-kda "true" toxin via limited proteolysis with trypsin and separation of stable n-terminal domains by fast-performance liquid chromatography. immunodiffusion experiments and n-terminal sequence determination (applied to the major component isolated by sds-page) completed the analysis of the crystal protein c ... | 1994 | 7704829 |
| evaluation of granular corncob formulations of bacillus thuringiensis serovar israelensis against mosquito larvae using a semi-field bioassay method. | a semi-field bioassay method using commonly available laundry tubs evaluated efficacy and residual activity of 6 granular corncob formulations of bacillus thuringiensis serovar israelensis against laboratory-reared late 3rd- and early 4th-instar larvae of aedes taeniorhynchus introduced to the tubs. these formulations produced appreciable larval mortalities (up to 75%) for 9 days posttreatment, with indications of having more prolonged activity. the consistent posttreatment larval mortality tren ... | 1994 | 7707052 |
| protocol for the introduction of new bacillus thuringiensis israelensis products into the routine mosquito control program in germany. | the efficacy of new and frequently used formulations of bacillus thuringiensis israelensis (b.t.i.) has been evaluated in the laboratory and in the field conditions under which they will be used in germany. the principles governing the successful introduction of new formulations of microbial control agents into routine programs have been highlighted. the potency of the formulations in use (teknar, bactimos, and vectobac) and their efficacy against the indigenous mosquito species aedes vexans, ae ... | 1994 | 7707059 |
| membrane permeabilization by listeria monocytogenes phosphatidylinositol-specific phospholipase c is independent of phospholipid hydrolysis and cooperative with listeriolysin o. | we have examined potential cooperative interactions of listeria monocytogenes phosphatidylinositol-specific phospholipase c (pi-plc) and listeriolysin o (llo), a pore-forming hemolysin, in a liposome lysis assay. large unilamellar vesicles, approximately 0.1 micron in diameter, encapsulating the fluorescent probe calcein, were treated with pi-plc or llo at ph 6.0, and each was capable of causing dye release. with phosphatidylcholine/phosphatidylinositol/cholesterol liposomes at 0.1 microm lipid, ... | 1995 | 7708759 |
| bacillus thuringiensis protoxin: location of toxic border and requirement of non-toxic domain for high-level in vivo production of active toxin. | insecticidal crystal proteins, or protoxins, of bacillus thuringiensis are composed of two domains, an amino-terminal half essential for toxicity, and a carboxy-terminal half with an as yet unassigned function. to define the boundary of the two domains, sequential termination codons were introduced from the 3'-end of the dna sequence encoding the toxic domain of the 1155-residue cry1a(b) gene product. the mutated and the intact genes were placed under the control of the escherichia coli inducibl ... | 1995 | 7711901 |
| comparative toxicity of certain mosquitocidal compounds to larvivorous fish, poecilia reticulata. | toxicity of certain mosquitocidal compounds (both larvicides and adulticides) to the larvivorous fish poecilia reticulata was determined in the laboratory. among the various chemical insecticides tested, the synthetic pyrethroid deltamethrin was most toxic to fish (lc50 = 0.016 ppm), while the organophosphorus insecticide abate was least toxic (lc50 = 34 ppm). the bioinsecticides spherix (bacillus sphaericus) and bactoculicide (bacillus thuringiensis h-14) showed highest safety for the fish (lc5 ... | 1994 | 7713258 |
| specificity domain localization of bacillus thuringiensis insecticidal toxins is highly dependent on the bioassay system. | the bacillus thuringiensis cryla(a) and cryla(c) gene specificity regions were probed by creating and testing hybrid toxins both in vivo and in vitro against cultured insect cells or dissociated midgut epithelial cells. toxin threshold dose determinations revealed that cryla(c) is highly active against cultured choristoneura fumiferana cells (cf-1) whereas cryla(a) is nontoxic. in live insect bioassays, a reversed order of toxicity was observed. hybrid analysis revealed that the cryla(c) toxicit ... | 1994 | 7715447 |
| in vitro binding of bacillus thuringiensis var. israelensis individual toxins to midgut cells of anopheles gambiae larvae (diptera: culicidae). | midguts from anopheles gambiae fourth instars were dissected and processed for immuno-light microscopy. cloned insecticidal crystal proteins (icps) from bacillus thuringiensis var. israelensis (bti) were individually expressed in crystal-negative strains of bacillus thuringiensis. tissue sections of a. gambiae were incubated in vitro with each solubilized and trypsin-activated icp. immunodetection of cryiva, cryivb, cryivd and cyta toxins on sections was performed using purified rabbit igg direc ... | 1995 | 7720855 |
| increased efficacy of bacillus thuringiensis subsp. kurstaki in combination with tannic acid. | we identified tannic acid as an inexpensive additive that increased the efficacy of sublethal concentrations of bacillus thuringiensis subsp. kurstaki (berliner). tannic acid mimicked the active constituents contained in an aqueous, tannin-rich extract of taxus baccata (l.) bark that retarded development of heliothis virescens (f.) larvae at 10,000 ppm; most larvae remained in first and second stage when treated with 250-10,000 ppm of tannic acid. instar development of trichoplusia ni (hübner) l ... | 1995 | 7722082 |
| the insecticidal cryib crystal protein of bacillus thuringiensis ssp. thuringiensis has dual specificity to coleopteran and lepidopteran larvae. | the crystals found in sporulation extracts of bacillus thuringiensis (berliner) contain proteins that are highly toxic to insects. different crystal proteins exhibit distinct specificities for restricted groups of insects. an uncharacterized strain of b. thuringiensis (bts2), derived from china, was found to carry several crystal protein genes and to be toxic to a wide variety of insects, including some coleopterans. surprisingly, the coleopteran toxicity was traced to a cryib-class protein. the ... | 1995 | 7722342 |
| random amplified polymorphic dna fingerprinting of mosquito-pathogenic and nonpathogenic strains of bacillus sphaericus. | random amplified polymorphic dna fingerprinting was used to examine 31 mosquito-pathogenic and 14 nonpathogenic strains of bacillus sphaericus. we verified that dna bands that migrated the same distance in an agarose gel were homologous by using pcr-generated probes made from the random amplified polymorphic dna bands. the band patterns obtained with eight primers were analyzed by using the jaccard coefficient and unweighted pair group with arithmetic average clustering. pathogenic strains belon ... | 1995 | 7727272 |
| single amino acid changes in domain ii of bacillus thuringiensis cryiab delta-endotoxin affect irreversible binding to manduca sexta midgut membrane vesicles. | deletion of amino acid residues 370 to 375 (d2) and single alanine substitutions between residues 371 and 375 (fnigi) of lepidopteran-active bacillus thuringiensis cryiab delta-endotoxin were constructed by site-directed mutagenesis techniques. all mutants, except that with the i-to-a change at position 373 (i373a), produced delta-endotoxin as cryiab and were stable upon activation either by manduca sexta gut enzymes or by trypsin. mutants d2, f371a, and g374a lost most of the toxicity (400 time ... | 1995 | 7730254 |
| transcriptional regulation of the cryivd gene operon from bacillus thuringiensis subsp. israelensis. | the cryivd protein is involved in the overall toxicity of the bacillus thuringiensis subsp. israelensis parasporal inclusions and is one of the four major components of the crystals. determination of the dna sequence indicated that the cryivd gene is the second gene of an operon which includes three genes. the first one encodes a 19-kda polypeptide and has sequence homology with the orf1 gene of the bacillus thuringiensis cryiia and cryiic operons. the second and third genes have already been id ... | 1995 | 7730255 |
| expression of the genes for insecticidal crystal proteins in bacillus thuringiensis: cryiva, not cryivb, is transcribed by rna polymerase containing sigma h and that containing sigma e. | to investigate the mechanism of transcriptional regulation of cryiva and cryivb, encoding 130-kda dipteran-active crystal proteins, in bacillus thuringiensis subsp. israelensis, we introduced each gene into several sporulation mutants of bacillus subtilis. a spoiig mutation, the wild-type gene of which encodes sigma e precursor, completely blocked the cryivb transcription. in contrast, low but detectable transcription of cryiva was observed in the spoiig mutant. in the wild-type b. subtilis, no ... | 1995 | 7737485 |
| kinetics of bacillus thuringiensis toxin binding with brush border membrane vesicles from susceptible and resistant larvae of plutella xylostella. | an optical biosensor technology based on surface plasmon resonance was used to determine the kinetic rate constants for interactions between the cryia(c) toxin from bacillus thuringiensis and brush border membrane vesicles purified from susceptible and resistant larvae of diamondback moth (plutella xylostella). cryia(c) association and dissociation rate constants for vesicles from susceptible larvae were determined to be 4.5 x 10(3) m-1 s-1 and 3.2 x 10(-5) s-1, respectively, resulting in a calc ... | 1995 | 7744839 |
| mosquito larvicidal activity of escherichia coli with combinations of genes from bacillus thuringiensis subsp. israelensis. | the genes cryiva and cryivd, encoding 134- and 72-kda proteins, respectively, and the gene for a regulatory 20-kda polypeptide of bacillus thuringiensis subsp. israelensis (serovar h14) were cloned in all seven possible combinations by the escherichia coli expression vectors pt7 and puhe. the four combinations containing cryiva (cryiva alone, with cryivd, with the 20-kda-protein gene, and with both) displayed high levels of mosquito larvicidal activity in puhe. the toxicity of the combination of ... | 1995 | 7751296 |
| the genetic basis of the aggregation system in bacillus thuringiensis subsp. israelensis is located on the large conjugative plasmid pxo16. | the aggregation phenotypes agr+ and agr- of bacillus thuringiensis subsp. israelensis are correlated with a conjugation-like plasmid transfer and characterized by the formation of aggregates when the bacteria are socialized during exponential growth. we present evidence for the association of the agr+ phenotype with the presence of the large (135-mda) self-transmissible plasmid pxo16. | 1995 | 7751306 |
| bacillus cereus phage typing as an epidemiological tool in outbreaks of food poisoning. | bacillus cereus is responsible for an increasing number of food poisoning cases. by using 12 bacteriophages isolated from sewage, a typing scheme for b. cereus isolates from outbreaks or sporadic cases of food poisoning was developed. the phages belonged to three morphotypes. ten phages with contractile tails and icosahedral heads were members of the myoviridae family, and two phages with noncontractile tails belonged to the siphoviridae family. phage 11 represented a new species. it had an isom ... | 1995 | 7751369 |
| insect resistant rice generated by introduction of a modified delta-endotoxin gene of bacillus thuringiensis. | as a first step towards development of insect resistant rice we have introduced a truncated delta-endotoxin gene, cryia(b) of bacillus thuringiensis (b.t.) which has specific biological activity against lepidopteran insects into a japonica rice. to highly express the cryia(b) gene in rice the coding sequence was extensively modified based on the codon usage of rice genes. transgenic plants efficiently expressed the modified cryia(b) gene at both mrna and protein levels. bioassays using r2 genera ... | 1993 | 7764096 |
| cloning, heterologous expression, and localization of a novel crystal protein gene from bacillus thuringiensis serovar japonensis strain buibui toxic to scarabaeid insects. | recombinant escherichia coli strains harboring pag1, pag2, pkbb100, and pkbb101 were cloned by using antiserum constructed against 130-kda crystal protein antigen of bacillus thuringiensis serovar japonensis strain buibui. dnas in the recombinant strains hybridized to the 26-base oligonucleotide probe corresponding to n-terminal amino acids of the 130-kda crystal protein of strain buibui. cultures of the recombinant strains were toxic to larvae of the cupreous chafer, anomala cuprea. furthermore ... | 1994 | 7764305 |
| genetic engineering on bacillus thuringiensis insecticidal proteins. | 1994 | 7764780 | |
| cloning of a new cryia(a) gene from bacillus thuringiensis strain fu-2-7 and analysis of chimaeric cryia(a) proteins for toxicity. | we cloned the cryia(a) gene from bacillus thuringiensis strain fu-2-7, one of the toxin genes encoding lepidopteran-specific protoxins. sequence analysis of the gene showed two amino acid differences (pro77 to leu and phe965 to ser) from the cryia(a) of b. thuringiensis strain hd-1. we constructed chimaeric cryia(a) genes using fu-2-7 and hd-1 cryia(a) genes and isolated the chimaeric protoxins, as well as the parental ones, from escherichia coli cells harboring the recombinant plasmids to exami ... | 1994 | 7764972 |
| current research to develop the entomopathogen bacillus thuringiensis for horn fly control. | bacillus thuringiensis subspecies israelensis (bti) has been shown to produce at least two sporulation-specific proteins which result in larvicidal activity when incorporated in bioassays against horn flies (haematobia irritans l.). development of a new control technology for horn flies based on bti appears to be feasible through the use of recombinant dna technology. substantial work remains however, to develop new research tools and techniques for this application. | 1994 | 7765154 |
| recombinant bacillus thuringiensis crystal proteins with new properties: possibilities for resistance management. | to obtain bacillus thuringiensis crystal proteins with new properties and to identify the regions involved in insecticidal activity, we generated hybrid genes composed of cryic and cryie by in vivo recombination. analysis of the hybrid proteins showed that domain iii of cryic is involved in the toxicity towards spodoptera exigua and mamestra brassicae. transfer of this domain to cryie, which is not active against these insects, resulted in a new protein with a broader activity. this hybrid prote ... | 1994 | 7765229 |
| importance of the central region of 130-kda insecticidal proteins of bacillus thuringiensis var. israelensis for their activity in vivo and in vitro. | to delineate the mosquitocidal regions of the isrh3 (cryivb) and isrh4 (cryiva) proteins, which are two of the mosquitocidal 130-kda proteins contained in the crystalline protein bodies (cpbs) of bacillus thuringiensis var. israelensis (bti), a deletion analysis of these protein genes has been done. based on the evidence that each 130-kda protein had two mosquitocidal regions, n-terminal and c-terminal ones, and these two regions shared a common part in the center of the 130-kda proteins, delete ... | 1993 | 7765303 |
| nucleotide sequence of the gene encoding novel delta-endotoxin from bacillus thuringiensis serovar japonensis strain buibui specific to scarabaeid beetles. | a new isolate of bacillus thuringiensis serovar japonensis strain buibui, which was specific to scarab beetles (m. ohba et al., lett. appl. microbiol. 14:54, 1992), was shown to have a 130-kda insecticidal crystal protein (icp) (h. hori et al., j. appl. bacteriol. 76:307, 1994). clai restriction enzyme fragments of total cell dna of the isolate were cloned into e. coli (sato et al., curr. microbiol. 28:15, 1994). whole 3480-bp nucleotide sequence of the gene encoding 130-kda icp was determined, ... | 1995 | 7765896 |
| improved production of the insecticidal cryivd protein in bacillus thuringiensis using cryia(c) promoters to express the gene for an associated 20-kda protein. | previous studies have shown that a 20-kda protein enhances production of the insecticidal cyta and cryiva proteins of bacillus thuringiensis in escherichia coli as well as cyta production and crystal formation in b. thuringiensis. to determine whether the 20-kda protein could enhance cryivd production, an expression vector was constructed with the 20-kda open-reading frame under control of cryia(c) promoters and the cryivd gene under control of its own promoter. acrystalliferous cells of b. thur ... | 1995 | 7765910 |
| penicillin-g enhanced production of thuringiensin by bacillus thuringiensis sp. darmstadiensis. | the effect of penicillin-g on the production of the potential microbial insecticide thuringiensin by bacillus thuringiensis sp. darmstadiensis was studied. shake flask and 3-l jar fermentor studies showed that the addition of 360 units/ml penicillin-g at 9 h, when the fermentable sugar in the medium was about to be mostly consumed, improved thuringiensin production by more than 1-fold relative to the control. the dosage of 360 units/ml penicillin-g had only a modest effect on the growth of the m ... | 1995 | 7766105 |
| mapping and characterization of the entomocidal domain of the bacillus thuringiensis cryia(b) protoxin. | the amino acid sequences necessary for entomocidal activity of the cryia(b) protoxin of bacillus thuringiensis were determined. introduction of stop codons behind codons arg601, phe604 or ala607 showed that amino acid residues c-terminal to ala607 are not required for insecticidal activity and that activation by midgut proteases takes place distal to ala607. the two shortest polypeptides, deleted for part of the highly conserved beta-strand, were prone to proteolytic degradation, explaining thei ... | 1995 | 7770056 |
| bacillus thuringiensis protoxin: location of toxic border and requirement of non-toxin domain for high-level in vivo production of active toxin. | 1995 | 7773421 | |
| structure, function and engineering of bacillus thuringiensis toxins. | nature has provided potent insecticidal toxins as fermentation products of many bacillus thuringiensis strains. elucidation of structure-function relationships for this class of natural toxins is in its early stages. both direct experimentation and application of theoretical structure-function principles emerging from the rapidly growing field of protein structure are accelerating understanding of these toxins. coupled with the increasing demand for biologically sound pesticides, the benefits fr ... | 1995 | 7779517 |
| seven-helix bundles: molecular modeling via restrained molecular dynamics. | simulated annealing via restrained molecular dynamics (sa/md) has been used to model compact bundles of seven approximately (anti)parallel alpha-helices. seven such helix bundles occur, e.g., in bacteriorhodopsin, in rhodopsin, and in the channel-forming n-terminal domain of bacillus thuringiensis delta-endotoxin. two classes of model are considered: (a) those consisting of seven ala20 peptide chains; and (b) those containing a single polypeptide chain, made up of seven ala20 helices linked by g ... | 1995 | 7787019 |
| cloning and sequencing of a beta-lactamase-encoding gene from the insect pathogen bacillus thuringiensis. | a beta-lactamase (bla)-encoding gene (bla) from bacillus thuringiensis (bt) was cloned and the nucleotide (nt) sequence was determined. both the nt sequence and deduced amino acid sequences reveal that the bt bla is very similar to that of b. cereus and other group a bla. the transcription start point was also determined. comparison of the upstream region of bt bla with that of other genes suggested the presence of three sequence elements that might be involved in promoter function: the -10 (tcg ... | 1995 | 7789815 |
| distribution of cryv-type insecticidal protein genes in bacillus thuringiensis and cloning of cryv-type genes from bacillus thuringiensis subsp. kurstaki and bacillus thuringiensis subsp. entomocidus. | dna dot blot hybridizations with a cryv-specific probe and a cryi-specific probe were performed to screen 24 bacillus thuringiensis strains for their cryv-type (lepidopteran- and coleopteran-specific) and cryi-type (lepidopteran-specific) insecticidal crystal protein gene contents, respectively. the cryv-specific probe hybridized to 12 of the b. thuringiensis strains examined. most of the cryv-positive strains also hybridized to the cryi-specific probe, indicating that the cryv genes are closely ... | 1995 | 7793960 |
| biochemical and morphological changes in rat muscle cultures caused by 28,000 mol. wt toxin of bacillus thuringiensis israelensis. | the 28,000 mol. wt protein of bacillus thuringiensis israelensis showed a high degree of toxicity to rat muscle in culture. application of 1 microgram/ml to the culture medium completely inhibited cell fusion. reversibility of this effect was demonstrated by replacement of the culture medium with fresh medium, and the consequence was that cell fusion was resumed. when differentiated myotubes were treated with 1 microgram/ml of the toxin, the spontaneous contractile activity was abolished within ... | 1994 | 7801348 |
| coleopterancidal delta-endotoxin and constructing its genomic library. | the composition of crystal proteins and plasmid patterns in five new coleopterancidal strains of bacillus thuringiensis were investigated. larvae of plagiodera versicolora were chosen as a model insect in bioassay. strain ym-03 had the highest toxicity. plasmid patterns were detected by rapid agarose gel electrophoresis. it was demonstrated that plasmid patterns of five bt strains were quite different. the partial amino acid sequences of the n-terminal of crystal protein from ym-03 were analyzed ... | 1994 | 7803692 |
| promotion of cytotoxic t-cell generation in mixed leukocyte culture by phosphatidylinositol-specific phospholipase c from bacillus thuringiensis. | phosphatidylinositol-specific phospholipase c (piplc) from bacillus thuringiensis, which cleaves phosphatidylinositol or glycosylphosphatidylinositol on the external cell surface to generate a second messenger for intracellular signal transduction (s. rahman et al., febs lett. 303:193-196, 1992), was found to preferentially promote the generation of alloantigen-specific cytotoxic t lymphocytes in mixed leukocyte culture. piplc affected an early stage of cytotoxic t-lymphocyte activation in cultu ... | 1995 | 7806363 |
| integrated management of waste tire mosquitoes utilizing mesocyclops longisetus (copepoda: cyclopidae), bacillus thuringiensis var. israelensis, bacillus sphaericus, and methoprene. | this study evaluated the compatibility and efficacy of using a predatory copepod, mesocyclops longisetus in concert with 3 "biorational" compounds for mosquito control in waste tires. the toxicity of bacillus thuringiensis var. israelensis (b.t.i), bacillus sphaericus, and methoprene to mesocyclops longisetus was assessed in the laboratory using concentrations 10 times the maximum labeled or suggested rate and based on a water depth of 7.6 cm. microbials were tested using mature copepods exposed ... | 1994 | 7807078 |
| emergency control of aedes aegypti in the dominican republic using the scorpion 20 ulv forced-air generator. | in an effort to develop a more effective measure for use in emergency control of the dengue vector aedes aegypti. applications of a combination of a larvicide (bacillus thuringiensis israelensis [b.t.i.]) and an adulticide (permethrin) were made using a truck-mounted forced-air generator (scorpion 20) and evaluated in the dominican republic. this method has the potential to simultaneously control adults and larvae. in bioassay cages placed in household water containers at the time of application ... | 1994 | 7807084 |
| zwittermicin a-producing strains of bacillus cereus from diverse soils. | bacillus cereus uw85 produces a novel aminopolyol antibiotic, zwittermicin a, that contributes to the ability of uw85 to suppress damping-off of alfalfa caused by phytophthora medicaginis. uw85 produces a second antibiotic, provisionally designated antibiotic b, which also contributes to suppression of damping-off but has not been structurally defined yet and is less potent than zwittermicin a. the purpose of this study was to isolate genetically diverse strains of b. cereus that produce zwitter ... | 1994 | 7811080 |
| is231 and other bacillus thuringiensis transposable elements: a review. | bacillus thuringiensis is an entomopathogenic bacterium whose toxicity is due to the presence in the sporangia of delta-endotoxin crystals active against agricultural pests and vectors of human and animal diseases. most of the genes coding for these toxin proteins are plasmid-borne and are generally structurally associated with insertion sequences (is231, is232, is240, isbt1 and isbt2) and transposons (tn4430 and tn5401). several of these mobile elements have been shown to be active and are beli ... | 1994 | 7813910 |
| is231a insertion specificity: consensus sequence and dna bending at the target site. | in its natural host, bacillus thuringiensis, the insertion sequence is231a is preferentially inserted into the terminal inverted repeats of the transposon tn4430. using a novel transposition assay, we demonstrate that the tn4430 ends behave as insertion hot spots for is231a in escherichia coli. sequence analysis reveals that is231a insertion sites match the 5'-ggg(n)5ccc-3' consensus. however, this consensus is not the only determinant of is231a insertion specificity. although both tn4430 ends h ... | 1994 | 7830551 |
| elucidation of the mechanism of cryiiia overproduction in a mutagenized strain of bacillus thuringiensis var. tenebrionis. | nb176 is a bacillus thuringiensis mutant derived by gamma-irradiation of nb125 bacillus thuringiensis var. tenebrionis (krieg). it exhibits two interesting phenotypes: (i) oligosporogeny and (ii) twofold to threefold overproduction of the cryiiia protein. southern profiles of the nb176 strain showed an additional copy(s) of the cryiiia gene located on a 4 kb hindiii fragment, in addition to the expected cryiiia gene on a 3 kb hindiii fragment. each cryiiia gene-bearing hindiii fragment was clone ... | 1994 | 7830581 |
| characterization of the bacillus anthracis s-layer: cloning and sequencing of the structural gene. | bacillus anthracis, a gram-positive, spore-forming bacterium, is the etiological agent of anthrax. the gene coding for the s-layer protein (sap) was cloned on two contiguous fragments in escherichia coli, and the complete sequence of the structural gene was determined. the protein, sap, is composed of 814 residues, including a classical prokaryotic 29-amino-acid signal peptide. the mature form has a calculated molecular mass of 83.7 kda and a molecular mass of 94 kda on a sodium dodecyl sulfate- ... | 1995 | 7836294 |
| [bioassays with entomopathogenic bacteria]. | 1994 | 7838980 | |
| cytolytic differences among lepidopteran cell lines exposed to toxins of bacillus thuringiensis subsp. kurstaki (hd-263) and aizawai (hd-112): effect of aminosugars and n-glycosylation. | comparison of lytic-dose response behavior of seven lepidopteran cell lines to the activated delta-endotoxin polypeptides of bacillus thuringiensis subspecies kurstaki (hd-263) and aizawai (hd-112) indicated distinct differences among the lines. the lines derived from spodoptera species s. exigua (urc-se-1a) and s. littoralis (uiv-sl-575) were more susceptible to lysis by aizawai toxin (bta) than kurstaki toxin (btk) as were cells from the lymantria dispar line (iplb-ld652y). however, the concen ... | 1994 | 7842169 |
| dengue vector control: present status and future prospects. | dengue fever (df) and dengue haemorrhagic fever (dhf) have been the most common urban diseases in southeast asia since the 1950s. more recently, the diseases have spread to central and south america and are now considered as worldwide diseases. both aedes aegypti and aedes albopictus are involved in the transmission of df/dhf in southeast asian region. the paper discusses the present status and future prospects of aedes control with reference to the malaysian experience. vector control approache ... | 1994 | 7844836 |
| [the acute toxicity of a bacterial insecticidal preparation containing a beta-exotoxin]. | the acute toxicity of a new bulgarian bioinsecticide preparation is determined, produced on the basis of bacillus thuringiensis containing 0.1% beta-exotoxin by oral, dermal, inhalational and intraperitoneal introduction in experimental animals. the evaluation of the toxicity is performed by a complex of toxicometric, integral, haematologic and pathologicoanatomic methods according to the who and usa criteria for studying the safety of the microbic agents for plant protection. it is already esta ... | 1993 | 7845961 |
| role of the exosporium in the stability of the bacillus sphaericus binary toxin. | the persistence of toxicity of the bacillus sphaericus 1593 binary toxin was compared when produced in b. sphaericus, inside the exosporium, or in a recombinant b. thuringiensis strain, outside the exosporium. the stability of the toxin crystal was affected by temperature and quality of the water, but not by the location of the production in the bacterial cell. | 1994 | 7851734 |
| the assembly and organization of the alpha 5 and alpha 7 helices from the pore-forming domain of bacillus thuringiensis delta-endotoxin. relevance to a functional model. | the pore-forming domain of bacillus thuringiensis insecticidal cryiiia delta-endotoxin contains two helices, alpha 5 and alpha 7, that are highly conserved within all different cry delta-endotoxins. to gain information on the mode of action of delta-endotoxins, we have used a spectrofluorimetric approach and characterized the structure, the organization state, and the ability to self-assemble and to co-assemble within lipid membranes of alpha 5 and alpha 7. circular dichroism (cd) spectroscopy r ... | 1995 | 7852320 |
| synergism of mosquitocidal toxicity between cyta and cryivd proteins using inclusions produced from cloned genes of bacillus thuringiensis. | the toxicity to mosquito larvae of the parasporal body produced by bacillus thuringiensis subsp. israelensis and the pg-14 isolate of b. thuringiensis subsp. morrisoni is at least 20-fold greater than any of the four mosquitocidal proteins of which it is composed (cyta, cryiva, b, and d). this high toxicity is postulated to be due to synergistic interactions among parasporal proteins. however, this remains controversial because values reported for the specific toxicity of individual proteins, es ... | 1994 | 7854129 |
| cloning and characterization of a bacillus thuringiensis homolog of the spoiiid gene from bacillus subtilis. | the spoiiid protein of bacillus subtilis (bs) is a small dna-binding protein that is essential for gene expression of the mother cell compartment during sporulation. we have cloned a dna fragment from bacillus thuringiensis (bt) that showed a specific hybridization with the bs spoiiid gene. sequence analysis found an open reading frame encoding 90 amino acids (aa), which are 89% identical to the deduced aa sequence of bs spoiiid. upstream from the transcription start point (tsp), a nucleotide se ... | 1995 | 7867944 |
| interaction of the insecticidal crystal protein cryia from bacillus thuringiensis with amino acid transport into brush border membranes from bombyx mori larval midgut. | the activities of three related bacillus thuringiensis delta-endotoxins, designated cryia(a), cryia(b), and cryia(c), as inhibitors of k(+)-dependent amino acid transport into membrane vesicles prepared from the anterior and posterior portions of bombyx mori larval midgut were measured. under experimental conditions similar to those occurring in vivo (membrane potential approximately -100 mv, inside negative; ph 7.2in/8.8out; an inwardly directed k+ gradient) cryia(a) toxin produced a clear dose ... | 1995 | 7876592 |
| germination of bacillus thuringiensis spores in bacteriophagous nematodes (nematoda: rhabditida). | during screening of bacillus thuringiensis isolates for nematicidal activity it was observed that spores of b. thuringiensis germinated in the intestine of bacteriophagous nematodes in the presence of antibiotics. this phenomenon was studied more closely by scanning electron microscopy. the nematodes were fed with bacterial spore-crystal mixtures in axenic culture medium supplemented with tetracyclin and chloramphenicol. germination of spores was rare but was more frequently observed in panagrel ... | 1995 | 7876593 |
| [testing effectiveness of selected bio-insecticides for reducing the population of cockroaches (blattella germanica l.)]. | the usefulness was tested of the biological insecticides containing b. thuringiensis available in the market in the eradication of cockroaches. thuridan was the most effective out of the tested insecticides in reducing the number of the insects. its higher activity in relation to thuricide was evident at all tested concentrations. males were more sensitive than females. on the other hand, no significant response of cockroaches to m-one preparation was noted, since the per cent of dying insects w ... | 1994 | 7878338 |
| [studies on the ecological distribution of bacillus thuringiensis in forest soils of china]. | a total of 384 forest soils samples at 0-5cm depth collected from 8 forest site zones (13 natural reserves) in china were examined for the distribution of bacillus and bacillus thuringiensis. the 79 cultures (4.21%) in 1873 isolates of bacillus collected referable to the bacillus thuringiensis. soil ph, moisture content and soil nutrient were determined. rules of the ecological distribution of bacillus thuringiensis of 8 forest site zones in china were analysed. toxicities against 6 species of i ... | 1994 | 7879387 |
| inheritance of resistance to bacillus thuringiensis subsp. tenebrionis cryiiia delta-endotoxin in colorado potato beetle (coleoptera: chrysomelidae). | we investigated the genetic inheritance of colorado potato beetle, leptinotarsa decemlineata (say), resistance to bacillus thuringiensis cryiiia delta-endotoxin. standard reciprocal crosses and backcrosses between susceptible (s) and resistant (r) strains were used to determine the characteristics of resistance. analysis of probit lines from the f1 reciprocal crosses indicated that b. thuringiensis delta-endotoxin resistance was inherited autosomaly without maternal effects. we estimated the deg ... | 1995 | 7884077 |
| variation in tolerance to bacillus thuringiensis among and within populations of the spruce budworm (lepidoptera: tortricidae) in ontario. | variation in tolerance to bacillus thuringiensis berliner subsp. kurstaki (strain hd-1-s-1980) among and within populations of the spruce budworm, choristoneura fumiferana (clemens), was assessed in the laboratory. force-feeding assays using offspring of females collected as pupae from nine locations throughout ontario and from a laboratory colony (dcf) demonstrated limited variation in tolerance among populations. variation among populations was comparable with the variation observed among repe ... | 1995 | 7884080 |
| cloning and expression of a receptor for an insecticidal toxin of bacillus thuringiensis. | environmentally friendly toxins of bacillus thuringiensis are effective in controlling agriculturally and biomedically harmful insects. however, little is known about the insect receptor molecules that bind these toxins and the mechanism of insecticidal activity. we report here for the first time the cloning and expression of a cdna that encodes a receptor (bt-r1) of the tobacco hornworm manduca sexta for an insecticidal toxin of b. thuringiensis. the receptor is a 210-kda membrane glycoprotein ... | 1995 | 7890666 |
| mutations in domain i of bacillus thuringiensis delta-endotoxin cryiab reduce the irreversible binding of toxin to manduca sexta brush border membrane vesicles. | site-directed mutagenesis was used to generate cryiab mutants at the selected n-terminal positions to study the function of domain i. structurally stable mutant proteins were tested for toxicity, receptor binding kinetics, and pore function. substitutions of tyrosine at position 153 with arginine (y153r) or alanine (y153a) did not affect toxicity appreciably, whereas replacing this tyrosine with aspartic acid (y153d) resulted in a great loss of toxicity. mutation of alanine at position 92 to glu ... | 1995 | 7890779 |
| bacillus thuringiensis delta-endotoxin and larval manduca sexta midgut brush-border membrane vesicles act synergistically to cause very large increases in the conductance of planar lipid bilayers. | brush-border membrane vesicles prepared from midguts of manduca sexta larvae were incorporated into planar phospholipid bilayers. addition of bacillus thuringiensis delta-endotoxin to the buffered salt solutions bathing these bilayers resulted in large irreversible increases in conductance. at ph 9.6, the smallest toxin-dependent increase in bilayer conductance observed was 13 ns. similar conductance increases were never observed in the absence of delta-endotoxin or in delta-endotoxin-treated bi ... | 1995 | 7891040 |
| a modified bioassay for microbial mosquito larvicides. | the proposed bioassay-the grid assay-eliminates the influence of cannibalism while allowing recycling to take place. the lc50 values of the grid assay were intermediate to those of the group and the individual assay. the grid assay thus reflects the true toxicity values of the microbial pesticides being tested. viable count studies of the microbial pesticides employed, viz., bacillus thuringiensis h-14 and bacillus sphaericus 2362, performed along with the assay support the results of the bioass ... | 1994 | 7896324 |
| diversity of bacillus thuringiensis environmental isolates showing larvicidal activity specific for mosquitoes. | seven mosquito-specific strains of bacillus thuringiensis isolated in japan were examined for their flagellar (h) antigenicities and the properties of parasporal inclusion proteins. they were assigned to six h serovars: serovar fukuokaensis (h 3ade); serovar canadensis (h 5ac); serovar darmstadiensis (h 10); serovar kyushuensis (h 11ac); serovar shandongiensis (h 22); and an undescribed serovar belonging to h serotype 20. purified parasporal inclusions exhibited moderate mosquito larvicidal acti ... | 1993 | 7903978 |
| alkaline phosphodiesterase i release from eucaryotic plasma membranes by phosphatidylinositol-specific phospholipase c. iii. the release from tumor cells. | 1. alkaline phosphodiesterase i release from two tumor cell lines, kb iii or ah-130 cells, by the action of phosphatidylinositol-specific phospholipase c (piplc) of bacillus thuringiensis was studied. 2. a significant amount of alkaline phosphodiesterase i was released from both the cell suspension and homogenate of kb iii cells, but not from ah-130 cells. 3. the release of the enzyme from kb iii cells was dependent on, or proportional to, the reaction time and the piplc or cell concentrations. ... | 1993 | 7904575 |
| mosquitocidal toxins of bacilli and their genetic manipulation for effective biological control of mosquitoes. | the identification, cloning, and characterization of protein toxins from various species of bacilli have demonstrated the existence of mosquitocidal toxins with different structures, mechanisms of action, and host ranges. a start has been made in understanding the polypeptide determinants of toxicity and insecticidal activity, and the purification of toxins from recombinant organisms may lead to the elucidation of their x-ray crystal structures and the cloning of brush border membrane receptors. ... | 1993 | 7905597 |
| use of an operon fusion to induce expression and crystallisation of a bacillus thuringiensis delta-endotoxin encoded by a cryptic gene. | a delta-endotoxin gene previously cloned from bacillus thuringiensis subsp. galleriae has been shown by a combination of restriction mapping and dna sequence analysis to be a cryiib clone; in common with other cryiib genes it was found to lack a functional promoter. addition of a promoter resulted in expression of the gene in bacillus thuringiensis but did not result in the formation of the crystalline inclusions normally associated with such toxins. inclusion formation was only observed when th ... | 1994 | 7906381 |
| the receptor for bacillus thuringiensis cryla(c) delta-endotoxin in the brush border membrane of the lepidopteran manduca sexta is aminopeptidase n. | a 120 kda glycoprotein in the larval midgut membrane of the lepidopteran manduca sexta, previously identified as a putative receptor for bacillus thuringiensis cryla(c) delta-endotoxin, has been purified by a combination of protoxin affinity chromatography and anion exchange chromatography. in immunoblotting experiments, the purified glycoprotein has the characteristics predicted of the receptor: it binds cryla(c) toxin in the presence of glcnac but not galnac; it binds the lectin sba; but it do ... | 1994 | 7908713 |
| incorporation of body components of diverse microorganisms by larval mosquitoes. | a pulse-purge schedule of exposure to labeled microorganisms was used to compare their digestibility by larval mosquitoes. larvae were placed for an hour in suspensions of diverse axenically grown microorganisms that had been labeled with radioactive carbon (in the form of glucose or glycine). the guts of these mosquitoes were then purged with nonlabeled sephadex particles for 30 min, and retained radioactivity was measured. larvae imbibed no dissolved material. larval mosquitoes differ in their ... | 1994 | 7912260 |
| characterization of bacillus thuringiensis and related bacteria by ribosomal rna gene restriction fragment length polymorphisms. | ribosomal rna gene restriction patterns have been determined for 43 strains of bacillus thuringiensis representing 10 serovars and eight reference strains of b. anthracis, b. cereus and b. mycoides. strains within a b. thuringiensis serovar produced highly related or identical ribotype patterns: in particular, 12 strains of serovar israelensis, five strains of serovar kurstaki, two strains of serovar galleriae and three strains of serovar aizawa produced ribotype patterns consistent with serotyp ... | 1994 | 7912979 |
| functional analysis of block 5, one of the highly conserved amino acid sequences in the 130-kda cryiva protein produced by bacillus thuringiensis subsp. israelensis. | there are five amino acid sequences highly conserved among bacillus thuringiensis delta-endotoxins. we have changed the amino acid residues in block 5, one of the conserved sequences, of cryiva. when the amino acid residues with charged side chains were replaced by others, the amount of production of the altered cryiva protein was markedly decreased. it is suggested that the decrease is caused by the unstable conformation of the altered cryiva protein molecule, as judged by digestion with trypsi ... | 1994 | 7913448 |
| [comparative effectiveness of bacterial larvicides against mosquito and bloodsucking midges]. | 1994 | 7915702 | |
| structural and functional studies of a synthetic peptide mimicking a proposed membrane inserting region of a bacillus thuringiensis delta-endotoxin. | in order to study the mechanism of action of bacillus thuringiensis delta-endotoxins, a synthetic 31-mer peptide corresponding to the sequence of a putative pore-forming segment of the cryla(c) toxin was characterized structurally and functionally. the peptide maps onto the central helix (alpha 5) of the six-helix bundle of domain i of the crystal structure of the cryiiia toxin. cd and nmr spectroscopic studies indicated that the peptide exists as an alpha-helix in methanol and a random coil in ... | 1994 | 7920867 |
| biochemical characterization of bacillus thuringiensis cytolytic delta-endotoxins. | the entomocidal delta-endotoxins cyta and cytb produced by bacillus thuringiensis (bt) subspecies israelensis and kyushuensis respectively showed a similar level of toxicity to mosquito larvae but were not toxic to the larvae of the lepidopteran manduca sexta. cyta and cytb are also similar in sequence, predicted secondary structure and alpha-helical content, the only obvious difference being a c-terminal fifteen residue 'tail' on cytb. investigations of the function, if any, of the cytb c-termi ... | 1994 | 7921240 |
| survival and respiratory activity of genetically engineered pseudomonas spp. exposed to antimicrobial agents in broth and soil. | the effectiveness of seven chemical disinfectants were tested against genetically engineered pseudomonas spp. under optimal growth conditions. each chemical was tested to determine how quickly 10(8) cells/ml pseudomonas fluorescens c5t (containing bacillus thuringiensis endotoxin gene) were killed in king's b broth at 30 degrees c. the minimal bactericidal concentrations (mbc) for calcium hypochlorite, benzalkonium chloride, germiphene and spectrum clear bath were 0.06% (w/v), 0.01% (w/v), 0.08% ... | 1994 | 7921352 |
| distribution of endogenous and exogenous 5'-nucleotidase on bovine spermatozoa. | a polyclonal rabbit antibody against 5'-nucleotidase purified from bull seminal plasma was used to localize the antigen on bovine spermatozoa. spermatozoa taken from the ampulla of the vas deferens showed strong immunofluorescence at the anterior rim of the head portion. evaluation of spermatozoa prepared from different segments of the seminal pathway indicated the presence of the antigen already in rete testis and epididymal spermatozoa. on cryostat sections of testis tissue a positive immunore ... | 1994 | 7928408 |
| insect resistance of transgenic plants that express modified bacillus thuringiensis cryia(b) and cryic genes: a resistance management strategy. | tobacco and tomato plants were generated exhibiting insect resistance due to the introduction of modified cryia(b) and cryic genes of bacillus thuringiensis. limited modifications at selected regions of the coding sequences of both genes are sufficient to obtain resistance against spodoptera exigua, heliothis virescens and manduca sexta. the criteria used to modify both genes demonstrate that the removal of sequence motifs potentially resulting in premature polyadenylation and transcript instabi ... | 1994 | 7948900 |
| a comparison and analysis of the toxicity and receptor binding properties of bacillus thuringiensis cryic delta-endotoxin on spodoptera littoralis and bombyx mori. | the binding of l-[35s]methionine in vivo labelled cryic toxin to its receptor in brush border membrane vesicle (bbmv's) prepared from spodoptera littoralis and bombyx mori was studied. both insect species were highly susceptible to the cryic toxin in bioassays, b. mori being 7-fold more sensitive to cryic than s. littoralis (lc50's of 10 ng/cm2 and 70 ng/cm2, respectively). competition and direct binding experiments revealed saturable high-affinity binding sites on bbmv's from both insects which ... | 1994 | 7957870 |
| characterization of the type strain of bacillus thuringiensis subsp. cameroun serotype h32. | the strain 273 b, the type strain of a h serotype of bacillus thuringiensis not yet characterized: b. thuringiensis subsp. cameroun, serotype h32, was isolated from soil samples collected in cameroon. this strain produces cuboidal parasporal bodies composed of two major proteins of 53 kda and 35 kda. n-terminal sequences of the major proteins share no homology with published sequences. only the 35 kda protein is susceptible to digestion by trypsin. a complex array of 9 plasmids was revealed. | 1994 | 7958777 |
| crystallization and preliminary x-ray diffraction studies of the lepidopteran-specific insecticidal crystal protein cryla(a). | a trypsin-activated cryla(a) protein from bacillus thuringiensis has been purified and crystallized. crystals belong to orthorhombic space group p2(1)2(1)2(1), with cell dimensions a = 53.3, b = 111.3 and c = 154.7 a. the crystals diffract to at least 2.2 angstrum resolution and are suitable for x-ray structural analysis. they contain a single molecule in the asymmetric unit. | 1994 | 7966278 |
| recent advances in vector control in filariasis. | three factors are involved when vector control is incorporated into an integrated control program for filariasis: (1) the vector species or species complex of each filarial worm; (2) type of control measures employed; (3) pesticide application. recent advances in vector control in filariasis include the use of bed nets, environmental manipulation, insecticides and biological control. three promising advances in vectrol control are the use of pathogenic bacteria such as bacillus thuringiensis h-1 ... | 1993 | 7973950 |
| new bacillus bacteriophage species. | nine new species of tailed bacillus phages, based on morphological and physicochemical properties, are defined. phage p10 is one of the largest viruses known. the total number of tailed bacillus phage species is presently 33. | 1994 | 7979971 |
| activation of the glycosyl-phosphatidylinositol-anchored membrane dipeptidase upon release from pig kidney membranes by phospholipase c. | incubation of pig kidney microvillar membranes with bacillus thuringiensis or staphylococcus aureus phosphatidylinositol-specific phospholipase c (pi-plc) resulted in the release of a number of glycosyl-phosphatidylinositol (gpi)-anchored hydrolases, including alkaline phosphatase (ec 3.1.3.1), amino-peptidase p (ec 3.4.11.9), membrane dipeptidase (ec 3.4.13.19), 5'-nucleotidase (ec 3.1.3.5) and trehalase (ec 3.2.1.28). of these five ectoenzymes only for membrane dipeptidase was there a signific ... | 1994 | 7980426 |
| hydrolysis of cell surface inositol phospholipid leads to the delayed stimulation of phosphatidylinositol synthesis in bovine aortic endothelial cells. | in order to address the issue of how inositol phospholipid synthesis is controlled in a resting cell we looked for enhanced [3h]phosphatidylinositol (ptdins) labelling in response to the hydrolysis of cell surface ptdins. bacillus thuringiensis ptdins-plc when added to intact bovine aortic endothelial (bae) cells rapidly hydrolysed 9.1 +/- 1% of the total cellular ptdins. this result suggests that bae cells have a cell surface pool of ptdins. hydrolysis of cell surface ptdins, in contrast to the ... | 1994 | 7981239 |
| a small (2.4 mb) bacillus cereus chromosome corresponds to a conserved region of a larger (5.3 mb) bacillus cereus chromosome. | we have determined the sizes of the chromosomes of six bacillus cereus strains (range 2.4-4.3 mb) and constructed a physical map of the smallest b. cereus chromosome (2.4 mb). this map was compared to those of the chromosomes of four b. cereus strains and one b. thuringiensis strain previously determined to be 5.4-6.3 mb. of more than 50 probes, 30 were localized to the same half of the larger b. cereus and b. thuringiensis chromosomes. all 30 were also present on the small chromosome. twenty of ... | 1994 | 7984090 |
| structural and functional analysis of the promoter region involved in full expression of the cryiiia toxin gene of bacillus thuringiensis. | the promoter region of the cryiiia toxin gene of bacillus thuringiensis is composed of at least three domains: an upstream region extending from nucleotide positions -635 to -553 (with reference to the translational start codon of cryiiia), an internal region extending from nucleotide positions -553 to -367, and a downstream region extending from nucleotide position -367 to +18. deletion analysis and transcriptional fusions to the lacz gene indicate that full expression of cryiiia requires the a ... | 1994 | 7984098 |
| the relationship between phospholipid content and ca2+-atpase activity in the sarcoplasmic reticulum. | the relationship between the phospholipid composition of sarcoplasmic reticulum and the activity of the ca2+, mg2+-stimulated atpase was analyzed by digestion of membrane phospholipids with phospholipase c and a2 enzymes of diverse specificity and by detergent extraction. phospholipase c of clostridium perfringens and clostridium welchii, that hydrolyze preferentially phosphatidylcholine (pc), inhibited the ca2+-atpase activity parallel with the depletion of phosphatidylcholine from the membrane ... | 1994 | 7986804 |
| laboratory and field evaluation of bacillus thuringiensis and b. sphaericus against mosquito larvae. | laboratory and field trials were carried out with two formulations of bacillus thuringiensis and four strains of bacillus sphaericus (b 42, b 64, b 87 and b 33) against mosquito larvae in different breeding habitats of tezpur, assam. lc90 of b. thuringiensis var israelensis (formulation teknar) against ae. albopictus, cx. quinquefasciatus and cx. gelidus were recorded as 0.443, 0.453 and 2.15 ppm respectively and lc90 of b. thuringiensis (deltox: vcrc b-17) against ae. albopictus, cx. quinquefas ... | 1994 | 7989680 |
| [expression of a partially modified delta-endotoxin gene from bacillus thuringiensis var. tenebrionis in transgenic potato plants]. | a modified gene (bt77) of delta-endotoxin from bacillus thuringiensis var. tenebrionis was constructed and cloned into pmon505. this binary transformation vector was introduced into agrobacterium tumefaciens strains containing different helper disarmed ti-plasmids, lba4404, a281, and cbe21. these agrobacterium strains were used to transform potato stem segments (s. tuberosum, cv desiree, resy, temp, granat). regenerants were selected on kanamycin-containing media. the presence of the bt77 sequen ... | 1994 | 7990839 |
| nucleotide sequence and analysis of an insertion sequence from bacillus thuringiensis related to is150. | a 5.8-kb dna fragment encoding the cryic gene from bacillus thuringiensis (bt) subsp. aizawai hd229 was subcloned into the pmex7 vector for expression in escherichia coli. in addition to the 135-kda cryic delta-endotoxin, this dna fragment also encoded a 30-kda polypeptide whose open reading frame (orfx) was located less than 200 bp upstream of cryic. nucleotide sequencing showed that orfx was truncated at the 5' end, and full sequence was obtained from a second overlapping clone. sequence analy ... | 1994 | 7991668 |
| expression of mosquitocidal toxin genes in a gas-vacuolated strain of ancylobacter aquaticus. | a series of plasmids bearing the binary toxin genes of bacillus sphaericus 2297 or 2317.3, the 100-kda toxin gene of b. sphaericus ssii-1, or the 130-kda (cryivb) toxin gene of bacillus thuringiensis subsp. israelensis were constructed and introduced into ancylobacter aquaticus by electroporation. the transformed a. aquaticus cells exhibited significant toxicity towards mosquito larvae, demonstrating a potential use of recombinant a. aquaticus for biological control of mosquitoes. | 1994 | 7993101 |
| transfer of shuttle vectors containing bacillus thuringiensis toxin gene into wild-type b. cereus, b. brevis and b. subtilis by electroporation. | gram positive and negative bacterial shuttle vectors carrying bacillus thuringiensis (b.t.) toxin gene were introduced by electroporation into wild-type bacillus cereus, b. brevis and b. subtilis. the transformation efficiencies for these bacteria were around 10(1)-10(4) transformants per micrograms dna based on the numbers of neomycin- and ampicillin-resistant colonies produced. the structure of the transferred plasmids proved identical with the original ones both in size and restriction patter ... | 1994 | 7993966 |