| interaction of bacillus thuringiensis and nuclear polyhedrosis virus in spodoptera exigua. | | 1975 | 773648 |
| insect resistant cotton plants. | we have expressed truncated forms of the insect control protein genes of bacillus thuringiensis var. kurstaki hd-1(cryia(b) and hd-73 (cryia(c) in cotton plants at levels that provided effective control of agronomically important lepidopteran insect pests. total protection from insect damage of leaf tissue from these plants was observed in laboratory assays when tested with two lepidopteran insects, an insect relatively sensitive to the b.t.k. insect control protein, trichoplusia ni (cabbage loo ... | 1990 | 1366777 |
| nucleotide sequence and transcriptional analysis of the polyhedrin gene of spodoptera exigua nuclear polyhedrosis virus. | the nucleotide sequence of a 1.1 kbp fragment of the multiple nucleocapsid nuclear polyhedrosis virus (mnpv) of spodoptera exigua (se) containing the polyhedrin gene was determined. an open reading frame (orf) of 738 nucleotides (nt) was detected. this orf encoded a protein of 246 amino acids with a predicted m(r) of 29k. the nucleotide and amino acid sequences were compared with the sequences of eight other npv polyhedrins. the semnpv polyhedrin protein was most closely related to s. frugiperda ... | 1992 | 1431809 |
| insecticidal properties of a crystal protein gene product isolated from bacillus thuringiensis subsp. kenyae. | a protoxin gene, localized to a high-molecular-weight plasmid from bacillus thuringiensis subsp. kenyae, was cloned on a 19-kb bamhi dna fragment into escherichia coli. characterization of the gene revealed it to be a member of the cryie toxin subclass which has been reported to be as toxic as the cryic subclass to larvae from spodoptera exigua in assays with crude e. coli extracts. to directly test the purified recombinant gene product, the gene was subcloned as a 4.8-kb fragment into an expres ... | 1992 | 1610185 |
| isolation and characterization of a novel insecticidal crystal protein gene from bacillus thuringiensis subsp. aizawai. | bacillus thuringiensis subsp. aizawai eg6346, a novel grain dust isolate, was analyzed by southern blot hybridization for its insecticidal crystal protein (icp) gene profile. strain eg6346 lacks previously characterized cryia icp genes yet does possess novel cryi-related gene sequences. a recombinant genomic plasmid library was constructed for strain eg6346 in escherichia coli. one recombinant plasmid, peg640, isolated from the library contained a novel icp gene on a 5.7-kb sau3a insert. the seq ... | 1991 | 2061280 |
| isolation and identification of paralytic peptides from hemolymph of the lepidopteran insects manduca sexta, spodoptera exigua, and heliothis virescens. | seven paralytic peptides were isolated and identified from lepidopteran hemolymph. all of these peptides cause rapid, rigid paralysis when injected into manduca sexta and some other lepidopteran larvae. each peptide contains 23 amino acid residues including 2 cysteines and the carboxyl termini are acidic. synthetic peptides in the disulfide or reduced forms, and as carboxyl-terminal acids or amides were equally paralytic. the most potent paralytic peptide, mas pp i, has the following sequence: h ... | 1991 | 2071576 |
| a novel bacillus thuringiensis gene encoding a spodoptera exigua-specific crystal protein. | only one of the four lepidoptera-specific crystal protein subclasses (cryic) bacillus thuringiensis was previously shown to be highly toxic against several spodoptera species. by using a cryic-derived nucleotide probe, dna from 25 different strains of b. thuringiensis was screened for the presence of homologous sequences. a putative crystal protein gene, considerably different from the cryic gene subclass, was identified in the dna of strain 4f1 (serotype kenyae) and cloned in escherichia coli. ... | 1990 | 2254254 |
| novel cloning vectors for bacillus thuringiensis. | seven replication origins from resident plasmids of bacillus thuringienis subsp. kurstaki hd263 and hd73 were cloned in escherichia coli. three of these replication origins, originating from plasmids of 43, 44, and 60 mda, were used to construct a set of compatible shuttle vectors that exhibit structural and segregational stability in the cry- strain b. thuringiensis hd73-26. these shuttle vectors, peg597, peg853, and peg854, were designed with rare restriction sites that permit various adaptati ... | 1990 | 2268153 |
| toxicity to spodoptera exigua and trichoplusia ni of individual p1 protoxins and sporulated cultures of bacillus thuringiensis subsp. kurstaki hd-1 and nrd-12. | the toxicities to neonate spodoptera exigua and trichoplusia ni of lyophilized powders obtained from sporulated liquid cultures (referred to as sporulated cultures) and escherichia coli-expressed p1 [cryia(a) cryia(b) cryia(c)] protoxins from three-gene strains of nrd-12 and hd-1 of bacillus thuringiensis subsp. kurstaki were determined by using diet incorporation bioassays. although sporulated cultures from both strains were more toxic to t. ni than s. exigua, there were no differences in toxic ... | 1990 | 2403254 |
| construction and analysis of an autographa californica nuclear polyhedrosis virus mutant lacking the polyhedral envelope. | an autographa californica nuclear polyhedrosis virus (acmnpv)-specific protein of 34 kda (pp34) is shown to be involved in the morphogenesis of the polyhderal envelope of baculoviruses. the region of the acmnpv genome encompassing ecori-h and -s (map positions 82.6-85.8) contains five open reading frames (orfs) forming one transcriptional unit. the bacterial beta-galactosidase (lacz) gene was inserted in phase with the n-terminal 12 amino acids of orf3, thereby intervening this gene. a recombina ... | 1989 | 2683364 |
| immunochemical characterization of juvenile hormone esterase from different species of lepidoptera. | cross-immunoreactivity of juvenile hormone esterase (jhe) from different species was tested using anti-jhe (trichoplusia ni) (noctuidae) polyclonal antibody. partial cross-reactivity was observed between jhe from hyphantria cunea, isia isabella (arctuidae) and spodoptera exigua (noctuidae) in immunoblot analysis. soluble antigen-antibody complex formation was observed between anti-jhe (t. ni) and antigen(s) from heliothis virescens (noctuidae) during immunotitration of antigen(s). using an elisa ... | 1987 | 3579958 |
| characteristics of a galactose-binding hemagglutinin (lectin) from hemolymph of spodoptera exigua larvae. | hemolymph from spodoptera exigua larvae agglutinates rabbit and human o erythrocytes. the agglutinin appears to be naturally occurring i.e., injury (by injection) or injection of larvae with fungal cells does not induce an increase in titer of hemolymph samples. hemagglutinin activity is destroyed by heat or edta, and galactosidic carbohydrates inhibit agglutination of both red blood cell types. the agglutinin was purified by affinity chromatography using an affi-gel ovalbumin column. binding to ... | 1986 | 3817244 |
| sex pheromones of noctuid moths. v. circadian rhythm of pheromone-responsiveness in males of autographa californica, heliothis virescens, spodoptera exigua, and trichoplusia ni (lepidoptera: noctuidae). | | 1965 | 5834924 |
| 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 ... | 1983 | 6666415 |
| enhanced production of insecticidal proteins in bacillus thuringiensis strains carrying an additional crystal protein gene in their chromosomes. | a two-step procedure was used to place a cryic crystal protein gene from bacillus thuringiensis subsp. aizawai into the chromosomes of two b. thuringiensis subsp. kurstaki strains containing multiple crystal protein genes. the b. thuringiensis aizawai cryic gene, which encodes an insecticidal protein highly specific to spodoptera exigua (beet armyworm), has not been found in any b. thuringiensis subsp. kurstaki strains. the cryic gene was cloned into an integration vector which contained a b. th ... | 1995 | 7487039 |
| characterization, sequencing and phylogeny of the ecdysteroid udp-glucosyltransferase gene from two distinct nuclear polyhedrosis viruses isolated from choristoneura fumiferana. | the ecdysteroid udp-glucosyltransferase (egt) gene isolated from a plaque-purified isolate of choristoneura fumiferana multinucleocapsid nuclear polyhedrosis virus (cfmnpv) was compared to its homologue from a defective mnpv virus (cfdef) present in wild type virus populations infecting the eastern spruce budworm, c. fumiferana. the egt genes were located in the same relative position within the virus genomes and their genomic location and arrangement were similar to that found in autographa cal ... | 1995 | 7595348 |
| adaptation of spodoptera exigua larvae to plant proteinase inhibitors by induction of gut proteinase activity insensitive to inhibition. | tobacco plants were transformed with a cdna clone of chymotrypsin/trypsin-specific potato proteinase inhibitor ii (pi2) under the control of a constitutive promoter. although considerable levels of transgene expression could be demonstrated, the growth of spodoptera exigua larvae fed with detached leaves of pi2-expressing plants was not affected. analysis of the composition of tryptic gut activity demonstrated that only 18% of the proteinase activity of insects reared on these transgenic plants ... | 1995 | 7644535 |
| 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 |
| comparative analysis of phagocytosis of fungal cells by insect hemocytes versus horse neutrophils. | in this study, the phagocytic ability of spodoptera exigua hemocytes was compared to horse neutrophils. in vitro assays showed that the insect granulocytes and horse neutrophils actively phagocytose fitc-labeled paecilomyces farinosus blastospores opsonized with s. exigua hemolymph lectin or horse serum, respectively. killing of fungal cells by the neutrophils and hemocytes was analyzed under in vitro conditions. neutrophils reduced the growth of p. farinosus up to 65% whereas no fungicidal acti ... | 1994 | 7768313 |
| deletion of the baculovirus ecdysteroid udp-glucosyltransferase gene induces early degeneration of malpighian tubules in infected insects. | deletion of the ecdysteroid udp-glucosyltransferase gene (egt) from the autographa californica nuclear polyhedrosis virus (acnpv) genome increases the speed of killing of this virus (d. r. o'reilly and l. k. miller, bio/technology 9:1086-1089, 1991). second-instar spodoptera exigua larvae are killed more rapidly by the egt deletion mutant of acnpv than by wild-type acnpv. unlike wild-type acnpv-infected larvae, larvae infected with an egt deletion mutant molt and resume feeding as mock-infected ... | 1995 | 7769717 |
| 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 |
| interaction of trichoplusia ni granulosis virus-encoded enhancin with the midgut epithelium and peritrophic membrane of four lepidopteran insects. | enhancin, an infectivity-enhancing protein from trichoplusia ni granulosis virus (tngv) was tested for its ability to increase autographa californica multiple nucleocapsid nuclear polyhedrosis virus (acmnpv) infection in the larvae of four lepidopteran insects. enhancin increased the mortality of acmnpv infection in all the four insect species tested. peritrophic membrane (pm) assays showed altered protein profiles in pms treated with enhancin in all the four species. this supports the hypothesi ... | 1994 | 8046398 |
| expression of the crystal protein gene under the control of the alpha-amylase promoter in bacillus thuringiensis strains. | the expression of an insecticidal crystal protein gene of bacillus thuringiensis under the control of the alpha-amylase gene promoter was investigated. the cryic gene, which encodes a protein known to have a unique activity against spodoptera (armyworm) species, was used in this investigation. the cryic gene was placed, along with the alpha-amylase promoter from b. subtilis, in a b. thuringiensis-derived cloning vector, generating a pair of recombinant plasmids, psb744 and psb745. the cloning ve ... | 1994 | 8074511 |
| isolation and sequencing of insecticidal peptides from the primitive hunting spider, plectreurys tristis (simon). | about 50 peptide toxins were purified from venom of the primitive hunting spider, plectreurys tristis. bioassay by injection into larval heliothis virescens (tobacco budworm) allowed selection of nine toxins for analysis of amino acid sequences. total sequences were determined for six of the more insecticidal peptides (46-49 amino acids) and three contained free carboxyl-terminal amino acids. these toxins (plectoxins) are paralytic and/or lethal when injected into insect pests such as the lepido ... | 1994 | 8157635 |
| insecticidal activity of the cryiia protein from the nrd-12 isolate of bacillus thuringiensis subsp. kurstaki expressed in escherichia coli and bacillus thuringiensis and in a leaf-colonizing strain of bacillus cereus. | a 4.0-kb bamhi-hindiii fragment encoding the cryiia operon from the nrd-12 isolate of bacillus thuringiensis subsp. kurstaki was cloned into escherichia coli. the nucleotide sequence of the 2.2-kb acci-hindiii fragment containing the nrd-12 cryiia gene was identical to the hd-1 and hd-263 cryiia gene sequences. expression of cryiia and subsequent purification of cryiia inclusion bodies resulted in a protein with insecticidal activity against heliothis virescens, trichoplusia ni, and culex quinqu ... | 1994 | 8161182 |
| new spodoptera exigua cell lines susceptible to spodoptera exigua nuclear polyhedrosis virus. | | 1993 | 8167910 |
| specificity of baculovirus p10 functions. | three functional domains in baculovirus p10 proteins have been postulated for aggregation, nuclear disintegration, and fibrillar structure formation (van oers et al., j. gen. virol. 74, 563-574, 1993). to study the specificity of these functions, a recombinant autographa californica nuclear polyhedrosis virus (accr1) was constructed in which the coding sequence of the p10 gene was replaced with the p10 sequence of the distantly related spodoptera exigua (se) mnpv. in accr1-infected cells the sem ... | 1994 | 8178439 |
| variations in the ability of galactose and mannose-specific lectins to bind to cell wall surfaces during growth of the insect pathogenic fungus paecilomyces farinosus. | the arrangement of carbohydrate molecules on surfaces of fungal cells may play an important role in nonself recognition of these microorganisms by potential invertebrate hosts. changes in the ability of various galactose and mannose-specific lectins to bind to surface components on cell walls of the insect pathogen paecilomyces farinosus were therefore examined during growth and differentiation of the fungus. fluorescein isothiocyanate conjugates of concanavalin a (con a, specific for alpha-d-ma ... | 1993 | 8330630 |
| evasion of host defense by in vivo-produced protoplast-like cells of the insect mycopathogen beauveria bassiana. | in vivo cells (hyphal bodies) of the hyphomycetous insect pathogen beauveria bassiana collected from host spodoptera exigua larval hemolymph were osmotically sensitive and lacked a well-defined cell wall. in light and electron microscope studies, a galactose-specific lectin purified from s. exigua hemolymph, concanavalin a (specific for alpha-mannose), and a polyclonal antibody to b. bassiana cell walls all bound to surfaces of in vitro-produced b. bassiana blastospores; however, none of these p ... | 1993 | 8376342 |
| immunologically unrelated heliothis sp. and spodoptera sp. midgut membrane-proteins bind bacillus thuringiensis cryia(b) delta-endotoxin. | the bacillus thuringiensis toxins, cryia(a), cryia(b), cryia(c) and cryic were used in a ligand-blot assay to detect specific toxin-binding proteins in the brush-border membranes of heliothis virescens, helicoverpa zea, spodoptera littoralis, spodoptera exigua and spodoptera litura. while cryia(a) and cryia(b) always recognize the same protein(s) in a given species, cryia(c) and cryic were found to bind to other proteins. polyclonal antibodies directed against the cryia(b) binding protein of h. ... | 1993 | 8383036 |
| immunological characterization of the vsv nucleocapsid (n) protein expressed by recombinant baculovirus in spodoptera exigua larva: use in differential diagnosis between vaccinated and infected animals. | vesicular stomatitis is a viral disease of cattle, pigs, and horses. the disease is characterized by vesicular lesions on the epithelium of the mouth, feet, and teats. the pathological lesions are virtually indistinguishable from that of foot-and-mouth disease. we have developed a recombinant baculovirus that expresses the nucleocapsid (n) protein of the new jersey serotype of vesicular stomatitis virus (vsvnj) in insect cells (sf9) and larvae (spodoptera exigua). the gene was expressed under co ... | 1993 | 8390753 |
| effect of beauveria bassiana and candida albicans on the cellular defense response of spodoptera exigua. | a marked difference in the cellular response of spodoptera exigua was observed when larvae were challenged with the insect mycopathogen beauveria bassiana versus the yeast candida albicans. both fungi were rapidly phagocytized by circulating hemocytes. the relative growth rate of c. albicans as measured by daughter cell formation was partially suppressed, whereas b. bassiana blastospores produced germ tubes at rates equivalent to those under in vitro conditions. limited growth by c. albicans wit ... | 1993 | 8463710 |
| cloning of a novel cryic-type gene from a strain of bacillus thuringiensis subsp. galleriae. | a novel cryic-type gene was isolated from a strain of bacillus thuringiensis subsp. galleriae. a new polymerase chain reaction (pcr) technique with a set of several oligonucleotide primer pairs specific to the cryic gene was used to screen a number of b. thuringiensis strains. pcr amplified several dna fragments ranging from 100 bp to 1 kb for b. thuringiensis strains containing a cryic gene. pcr fragments amplified from the bacillus thuringiensis subsp. galleriae hd29 dna differed from the frag ... | 1993 | 8476286 |
| nucleotide sequence and transcriptional analysis of the p10 gene of spodoptera exigua nuclear polyhedrosis virus. | the p10 gene of spodoptera exigua multiple nuclear polyhedrosis virus (semnpv) was localized on the xbai fragment h (5.1 kb) of the physical map of the viral genome. the coding sequence of the semnpv p10 gene is 264 nucleotides (nt) long corresponding to a predicted protein of 88 amino acids with an mhf of 9607. the semnpv p10 protein showed only limited amino acid identity (39% and 26%, respectively) to those of orgyia pseudotsugata mnpv (opmnpv) and autographa californica mnpv (acmnpv) and thu ... | 1993 | 8509757 |
| characterization of baculovirus insecticides expressing tailored bacillus thuringiensis cryia(b) crystal proteins. | full-length, truncated, and mature forms of the cryia(b) insecticidal crystal protein gene of bacillus thuringiensis were engineered into the p10 locus of autographa californica nuclear polyhdrosis virus (acnpv). a signal sequence of heliothis virescens juvenile hormone esterase was introduced at the n-terminus of these constructs to induce secretion. all recombinants, except those containing the mature toxin, produced high levels of cryia(b) icps in insect cells. thirty percent of the intracell ... | 1995 | 8568280 |
| a bacillus thuringiensis insecticidal crystal protein with a high activity against members of the family noctuidae. | the full characterization of a novel insecticidal crystal protein, named cry9ca1 according to the revised nomenclature for cry proteins, from bacillus thuringiensis serovar tolworthi is reported. the crystal protein has 1,157 amino acids and a molecular mass of 129.8 kda. it has the typical features of the lepidoptera-active crystal proteins such as five conserved sequence blocks. also, it is truncated upon trypsin digestion to a toxic fragment of 68.7 kda by removal of 43 amino acids at the n t ... | 1996 | 8572715 |
| replication of a mamestra brassicae nuclear polyhedrosis virus in a newly established mamestra brassicae cell line. | a continuous cell line, designated mbl-3, was newly established from minced neonate larvae of the cabbage armyworm, mamestra brassicae. this new cell line is heteroploid, containing triploid cells predominantly at the frequency of about 50%. doubling time of the cell population is 33 hrs. the akutsu isolate of a mamestra brassicae nuclear polyhedrosis virus (mbnpv) was examined for replication in 16 continuous cell lines, including the cell line mbl-3, from seven lepidoptera species: mamestra br ... | 1995 | 8578995 |
| baculovirus infection of spodoptera exigua larvae: lacz expression driven by promoters of early genes pe38 and me53 in larval tissue. | to follow the progression of infection of autographa californica multicapsid nuclear polyhedrosis virus (acmnpv) within tissues of its larval host, we have constructed acmnpv recombinants carrying lacz reporter genes under the control of the early virus promoters pe38 and me53, in addition to the authentic genes. the early promoter-lacz gene cassettes were located upstream of the very late polyhedrin gene. in infected insect cell lines, pe38 transcription is initiated at an early promoter, while ... | 1996 | 8609477 |
| domain iii substitution in bacillus thuringiensis delta-endotoxin cryia(b) results in superior toxicity for spodoptera exigua and altered membrane protein recognition. | to test our hypothesis that substitution of domain iii of bacillus thuringiensis delta-endotoxin (cry) proteins might improve toxicity to pest insects, e.g., spodoptera exigua, in vivo recombination was used to produce a number of cryia(b)-cryic hybrid genes. a rapid screening assay was subsequently exploited to select hybrid genes encoding soluble protoxins. screening of 120 recombinants yielded two different hybrid genes encoding soluble proteins with domains i and ii of cryia(b) and domain ii ... | 1996 | 8633853 |
| vip3a, a novel bacillus thuringiensis vegetative insecticidal protein with a wide spectrum of activities against lepidopteran insects. | a novel vegetative insecticidal gene, vip3a(a), whose gene product shows activity against lepidopteran insect larvae including black cutworm (agrotis ipsilon), fall armyworm (spodoptera frugiperda), beet armyworm (spodoptera exigua), tobacco budworm (heliothis virescens), and corn earworm (helicoverpa zea) has been isolated from bacillus thuringiensis strain ab88. vip3-insecticidal gene homologues have been detected in approximately 15% of bacillus strains analyzed. the sequence of the vip3a(b) ... | 1996 | 8643585 |
| different domains of bacillus thuringiensis delta-endotoxins can bind to insect midgut membrane proteins on ligand blots. | we investigated the role of the constituent domains of the cryia(b) and cryia(c) delta-endotoxins in binding to midgut epithelial cell membrane proteins of spodoptera exigua and manduca sexta on ligand blots. a collection of wild-type and cryic-cryia hybrid toxins was used for this purpose. as demonstrated elsewhere (r. a. de maagd, m. s. g. kwa, h. van der klei, t. yamamoto, b. schipper, j. m. vlak, w. j. stiekema, and d. bosch, appl. environ. microbiol. 62:1537-1543, 1996), cryia(b) domain iii ... | 1996 | 8702267 |
| identification of insect cell lines by dna amplification fingerprinting (daf). | fingerprint profiles were generated from twenty insect cell lines spanning the orders, lepidoptera, diptera, coleoptera and homoptera employing dna amplification fingerprinting (daf) with arbitrarily selected primers. the fingerprint pattern is a stable characteristic of the cell line because high and low passages generated the same profile. in addition, insect hosts and homologous cell lines generated similar profiles. all cell lines could be distinguished from each other with the following exc ... | 1996 | 8799737 |
| sequence and transcriptional analysis of the ubiquitin gene cluster in the genome of spodoptera exigua nucleopolyhedrovirus. | the nucleotide sequence of a 1200 bp dna fragment of spodoptera exigua nucleopolyhedrovirus (semnpv) was determined. this sequence contained a cluster of two open reding frames (orfs), one coding for a viral ubiquitin (v-ubi) and another with homology to orf2 of autographa californica (ac) mnpv and orgyia pseudotsugata (op) mnpv. the vubi orf is 240 nucleotides (nt) long, potentially encoding a protein of 80 amino acids with a predicted molecular mass of 9.4 kda. the amino acid sequence of the v ... | 1996 | 8811032 |
| in vivo and in vitro characterization of several isolates of spodoptera exigua nuclear polyhedrosis virus. | spodoptera exigua nuclear polyhedrosis viruses (senpvs), isolated form five geographically distinct regions of japan and thailand, were characterized by their dna restriction endonuclease pattern, level of virus production in a continuous cell line of s. exigua and biological activity to s. exigua larvae. the ecori and psti fragments exhibited similar overall patterns with minor differences. digestion of virus dna from a plaque-purified isolate, senpv-i1, with psti yielded 14 fragments and the e ... | 1995 | 8825303 |
| characterization of the ecdysteroid udp-glucosyltransferase gene from mamestra brassicae nucleopolyhedrovirus. | the ecdysteroid udp-glucosyltransferase (egt) gene of mamestra brassicae multinucleocapsid nucleopolyhedrovirus (mbmnpv) has been cloned and characterized. mbmnpv egt potentially encodes a protein of 528 amino acids. analysis of the substrate specificity of the mbmnpv egt protein showed that it mirrors that of autographa californica mnpv (acmnpv) egt. mbmnpv egt also appears to be secreted from infected cells. confirmation that the cloned gene encodes an active egt was obtained by transient expr ... | 1996 | 8922482 |
| involvement of two amino acid residues in the loop region of bacillus thuringiensis cry1ab toxin in toxicity and binding to lymantria dispar. | two amino acids, gly and ser, at positions 282 and 283 in the loop region of domain ii of cry1ab2 toxin are substituted with ala and leu in the cry1ab9-033 toxin. cry1ab2 exhibited about a 10-fold increase in toxicity and a 9-fold increase in binding affinity to lymantria dispar compared to cry1ab9-033. however, these toxins showed similar toxicity and binding affinity to manduca sexta and spodoptera exigua. heterologous competition assays and brush border membrane vesicle (bbmv) ligand blotting ... | 1996 | 8954096 |
| a synthetic cryic gene, encoding a bacillus thuringiensis delta-endotoxin, confers spodoptera resistance in alfalfa and tobacco. | spodoptera species, representing widespread polyphagous insect pests, are resistant to bacillus thuringiensis delta-endotoxins used thus far as insecticides in transgenic plants. here we describe the chemical synthesis of a cryic gene by a novel template directed ligation-pcr method. this simple and economical method to construct large synthetic genes can be used when routine resynthesis of genes is required. chemically phosphorylated adjacent oligonucleotides of the gene to be synthesized are a ... | 1996 | 8986755 |
| spodoptera exigua multicapsid nucleopolyhedrovirus deletion mutants generated in cell culture lack virulence in vivo. | the baculovirus spodoptera exigua multicapsid nucleopolyhedrovirus (semnpv) has high potential for development as a bio-insecticide for control of the beet armyworm (s. exigua). it is highly infectious for s. exigua larvae and its host range is very narrow. a prerequisite for such application is the possibility of growing this virus in large quantities, e.g. in insect cell lines. it was observed, however, that polyhedra of semnpv plaque-purified in se-ucr1 cells did not cause larval mortality or ... | 1996 | 9000107 |
| characterization of the ecdysteroid udp-glucosyltransferase gene of a single nucleocapsid nucleopolyhedrovirus of buzura suppressaria. | a putative ecdysteroid udp-glucosyltransferase (egt) gene was identified in the single nucleocapsid nucleopolyhedrovirus of buzura suppressaria (busunpv). this is the first egt gene to be characterized in a snpv, suggesting that egt genes are prevalent in nucleopolyhedroviruses and possibly in all baculoviruses. the open reading frame (orf) of the gene is 1539 nucleotides (nt) long, encoding a putative protein (egt) of 513 amino acids (aa) with a m of 58922. the 5' noncoding region contains thre ... | 1997 | 9037741 |
| enhanced bioactivity of recombinant baculoviruses expressing insect-specific spider toxins in lepidopteran crop pests | two genetically enhanced isolates of the autographa californica nuclear polyhedrosis virus (acmnpv) expressing insect-specific neurotoxin genes from the spiders diguetia canities and tegenaria agrestis were evaluated for their commercial potential. since prevention of feeding damage is of primary importance in assessing agronomic efficacy, a method for estimating the median time to cessation of feeding (ft50) was developed. neonate droplet feeding assays with preoccluded virus samples were condu ... | 1997 | 9056461 |
| cytolytic activity of bacillus thuringiensis cryic and cryiac toxins to spodoptera sp. midgut epithelial cells in vitro. | a sensitive lactate dehydrogenase (ldh) assay was modified to determine the cytolytic activity of bacillus thuringiensis cryic and cryiac delta endotoxins to viable collagenase-dissociated midgut epithelial cells (mec) from larvae of spodoptera frugiperda and spodoptera exigua. the mec preparations from these spodoptera sp. consisted predominantly of columnar cells (65-75%) and goblet cells (25-35%). time course microscopy experiments indicated that only the columnar cells became swollen during ... | 1997 | 9156349 |
| identification and functional analysis of a non-hr origin of dna replication in the genome of spodoptera exigua multicapsid nucleopolyhedrovirus. | the genome of spodoptera exigua multicapsid nucleopolyhedrovirus (semnpv) was screened for the presence of putative origins of dna replication (oris). using a transient dna replication assay, several fragments were identified that underwent semnpv-dependent dna replication in spodoptera frugiperda cells (sf-ae-21). preliminary sequence data revealed the presence of multiple copies of homologous repeats (hrs). restriction fragment xbal-f2 showed a distinct sequence reminiscent of autographa calif ... | 1997 | 9191948 |
| in vivo recombination between two strains of the genus nucleopolyhedrovirus in its natural host, spodoptera exigua. | the dna restriction map for the enzymes bamhi, bglii, psti, and xbai of semnpv-us (se-us), the best-studied nucleopolyhedrovirus strain isolated from spodoptera exigua in california, was used as a reference to construct that of semnpv-sp2 (se-sp2), a closely related spanish strain of the same virus. after coinfection of s. exigua with both the se-us and se-sp2 strains per os, a recombinant virus (semnpv-sur1 [se-sur1]) was detected after one passage which quickly replaced the parental viruses. a ... | 1997 | 9251191 |
| the p10 gene of spodoptera littoralis nucleopolyhedrovirus: nucleotide sequence, transcriptional analysis and unique gene organization in the p10 locus. | the p10 gene of the spodoptera littoralis (spli) multicapsid nucleopolyhedrovirus (mnpv) was identified. with a coding sequence of 315 nucleotides (nt), corresponding to a protein of 104 amino acids, the splimnpv p10 gene is the longest p10 gene known. this gene codes for a putative protein with an mr of 11130 and was found to be most closely related to the spodoptera exigua (se) mnpv p10 (49.4% amino acid identity) and most distant from the autographa californica (ac) mnpv p10 (20.0% amino acid ... | 1997 | 9267016 |
| characterization of the polyhedrin gene of spodoptera litura nuclear polyhedrosis virus. | the polyhedrin gene (polh) of a characteristically distinct spodoptera litura nuclear polyhedrosis virus isolate (simnpv) is identified in the hindiii-f fragment of the viral dna. the nucleotide sequence of the 1057 base pair (bp) region of this fragment contains an open reading frame (orf) without any intervening sequence for coding a polypeptide of 246 amino acids. analysis of the nucleotide sequence and deduced amino acid sequence indicate that this has more than 70% sequence identity to know ... | 1997 | 9311561 |
| maintenance of the k+ activity gradient in insect muscle compared in diptera and lepidoptera: contributions of metabolic and exchanger mechanisms | using a comparative approach, the mechanisms involved in maintenance of the transmembrane k+ activity gradients in the larval body-wall muscles of two insects, phormia terraenovae (diptera) and spodoptera exigua (lepidoptera), have been investigated. double-barrelled k+-selective microelectrodes were used to obtain simultaneous measurements of intracellular k+ activity and membrane potential, whilst ordinary microelectrodes were used to monitor input resistance. by application of a variety of ge ... | 1996 | 9319770 |
| characterization of a putative spodoptera exigua multicapsid nucleopolyhedrovirus helicase gene. | putative baculovirus helicases have been implicated as playing an important role in viral dna replication and host specificity. the spodoptera exigua multicapsid nucleopolyhedrovirus (semnpv) helicase is therefore of interest since the virus only infects the beet army worm. sequence analysis of the semnpv lef5-p39 (mu 46.5-55.1) region, which is collinear with the 39k-lef5 area in autographa californica mnpv (acmnpv), revealed an open reading frame (orf) of 3666 bp potentially encoding a protein ... | 1997 | 9400958 |
| occurrence of a common binding site in mamestra brassicae, phthorimaea operculella, and spodoptera exigua for the insecticidal crystal proteins cryia from bacillus thuringiensis. | specific binding to midgut membrane proteins is required for the toxicity of insecticidal crystal proteins (icp) from bacillus thuringiensis. a direct relationship between toxicity and binding has been proposed. it has been hypothesized that sharing of a single receptor by more than one icp could lead to the occurrence of multiple resistance in the event of an alteration in the common receptor. binding of cryia(a), cryia(b) and cryia(c), three structurally related icps, has been studied in phtho ... | 1997 | 9404010 |
| analysis of the ecdysteroid udp-glucosyltransferase gene of heliothis armigera single-nucleocapsid baculovirus. | an ecdysteroid udp-glucosyltransferase (egt) gene was identified from the single (s) nucleocapsid nucleopolyhedrovirus of heliothis armigera (hearnpv). in baculovirus-infected insects the viral enzyme (egt) plays a pivotal role in abrogating the insect molting process. the open reading frame of the egt gene is 1545 nucleotides long, encoding a putative protein of 515 amino acids with a mr of 59.1. the 5'-noncoding region contains a putative early (cagt) and late (taag) motif for transcription in ... | 1997 | 9482587 |
| toxicity and binding properties of the bacillus thuringiensis delta-endotoxin cry1c to cultured insect cells. | a better understanding of the mode of action of bacillus thuringiensis delta-endotoxins is needed to develop strategies which may prevent or slow down selection for resistance. we studied the effect of cry1c on several different cultured insect cell lines by means of toxicity assays, ligand blotting, and toxin binding studies. a clear difference in sensitivity toward cry1c between the insect cell lines was observed. spodoptera frugiperda cell line sf9 was most sensitive, whereas spodoptera exigu ... | 1998 | 9500946 |
| characterization of monoclonal antibodies against cell wall epitopes of the insect pathogenic fungus, nomuraea rileyi: differential binding to fungal surfaces and cross-reactivity with host hemocytes and basement membrane components. | monoclonal antibodies (mabs) were generated against epitopes on yeast-like hyphal bodies and hyphae of the entomopathogenic hyphomycete, nomuraea rileyi. two mabs (4c10, 2h4) bind to epitopes common to both hyphal bodies and hyphae, whereas mab 4e9 binds only to hyphal surfaces. 4c10 and 2h4 appear to be directed towards carbohydrate portions of cell surface mannoproteins, as evidenced by similarities in staining patterns between these mabs and concanavalin a on western blots of n. rileyi cell w ... | 1998 | 9548369 |
| molecular characterization and expression of the trichoplusia ni granulovirus helicase gene. | a putative dna helicase gene from the granulovirus of trichoplusia ni (tngv) was cloned, sequenced, and compared with the corresponding gene of several multinucleocapsid nucleopolyhedroviruses (mnpvs) including those from autographa californica (acmnpv), orgyia pseudotsugata (opmnpv), bombyx mori (bmnpv), and spodoptera exigua (semnpv). the tngv helicase gene (p137) encoded a helicase of 1158 amino acids with a predicted mass of 137 kda. comparison of p137 with acmnpv p143 revealed 44.5% identit ... | 1998 | 9603347 |
| the single-nucleocapsid nucleopolyhedrovirus of buzura suppressaria encodes a p10 protein. | the p10 gene of buzura suppressaria single-nucleocapsid nucleopolyhedrovirus (busunpv) was identified by virtue of its localization downstream from the autographa californica (ac) mnpv p26 homologue. the busunpv p10 gene encodes a protein of 94 amino acids. the amino acid sequence contains domains characteristic of baculovirus p10 proteins, e.g. a coiled-coil domain, a proline-rich motif and a positively charged c terminus. the highest amino acid homologies were found with the spodoptera littora ... | 1998 | 9634101 |
| specificity of multiple homologous genomic regions in spodoptera exigua nucleopolyhedrovirus dna replication. | the region upstream of the spodoptera exigua multicapsid nucleopolyhedrovirus (semnpv) ubiquitin gene contains four near-identical 68-bp-long palindromic repeats. this region, named sehr6 and located at map unit (m.u.) 88 of the semnpv genome on pseecori-2.2, showed structural homology to previously identified homologous regions (hrs) in a number of other baculoviruses. hrs function as enhancers of transcription and as putative origins (oris) of baculovirus dna replication. five additional hrs ( ... | 1998 | 9634102 |
| amplification of a chimeric bacillus gene in chloroplasts leads to an extraordinary level of an insecticidal protein in tobacco. | the bacillus thuringiensis (bt) crystal toxins are safe biological insecticides, but have short persistance and are poorly effective against pests that feed inside plant tissues. production of effective levels of these proteins in plants has required resynthesis of the genes encoding them. we report that amplification of an unmodified cryla(c) coding sequence in chloroplasts up to approximately 10,000 copies per cell resulted in the accumulation of an unprecedented 3-5% of the soluble protein in ... | 1995 | 9634777 |
| isolation of a strain of bacillus thuringiensis ssp. kurstaki hd-1 encoding delta-endotoxin cry1e. | a strain of bacillus thuringiensis, stb-1, toxic against spodoptera exigua, was isolated. bacillus thuringiensis stb-1 produced bipyramidal inclusions and reacted with the h antiserum of b. thuringiensis ssp. kurstaki. the plasmid and protein profiles of b. thuringiensis stb-1 were compared with those of its reference strains, ssp. kurstaki and ssp. kenyae. to verify the gene type of b. thuringiensis stb-1, pcr analysis was performed with spodoptera-specific cry gene primers. the result showed t ... | 1998 | 9674170 |
| comparison of field-collected ascovirus isolates by dna hybridization, host range, and histopathology. | six field-collected ascovirus isolates obtained from five noctuid species in the continental united states were compared with respect to the general relatedness of their dna, host range, and histopathology. two isolates were from spodoptera frugiperda, and the other four were from autographa precationis, heliothis virescens, helicoverpa zea, and trichoplusia ni. dna-dna hybridization studies showed that the six isolates belonged to three distinct viral species, with the isolates from s. frugiper ... | 1998 | 9709014 |
| a highly conserved genomic region in baculoviruses: sequence analysis of an 11.3 kbp dna fragment (46.5-55.1 m.u.) of the spodoptera exigua multicapsid nucleopolyhedrovirus. | a dna fragment of 11.3 kilobase pairs (kbp) in size of the baculovirus spodoptera exigua multicapsid nucleopolyhedrovirus (semnpv) genome (46.5 to 55.1 m.u.) was completely sequenced. analysis of the sequence revealed eleven potential open reading frames (orf). ten of these orfs showed significant amino acid identity to autographa californica mnpv (acmnpv) and orgyia pseudotsugata mnpv (opmnpv) genes p6.9, lef5, 38k, p19, p143, p25, p18, vp33, lef4, and vp39. one orf (xc12) has no homolog in oth ... | 1998 | 9725671 |
| environmental distribution and diversity of bacillus thuringiensis in spain. | bacillus thuringiensis was isolated from 301 out of 1,005 samples collected in spain from agricultural and non-cultivated soils, dust from stored products, and dead insects. based on the production of parasporal crystals, 1,401 isolates were identified as b. thuringiensis after examining 11,982 b. thuringiensis-like colonies. we found a greater presence of b. thuringiensis in dust from grain storages than in other habitats. sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the spore-c ... | 1998 | 9741114 |
| polyhedrin sequence determines the tetrahedral shape of occlusion bodies in thysanoplusia orichalcea single-nucleocapsid nucleopolyhedrovirus. | a nucleopolyhedrovirus (npv) isolated from the looper thysanoplusia orichalcea l. (lepidoptera: noctuidae) (thornpv) is occluded in a tetrahedral protein matrix. the orf of the thornpv polyhedrin gene contains 738 nt which code for 246 amino acids of the putative polyhedrin protein with an estimated molecular mass of 28,778 da. the promoter of this gene is similar in length to the promoter of spodoptera frugiperda npv (sfmnpv), with a 5 nt deletion before the start codon compared to those of oth ... | 1998 | 9780063 |
| timing of an early sporulation sequence of microsporidia in the genus vairimorpha (microsporidia: burenellidae) | an early sporulation event in the host midgut tissues has been reported for several species of microsporidia infecting diptera, hymenoptera, and lepidoptera. the role of these primary spores, formed between 35 and 96 h postinfection per os, has been suggested to be the cell to cell spread of infection within the host, but the sequence of events during the early sporulation stages has been reported for only a few species of microsporidia. we investigated these early life cycle events for two spec ... | 1998 | 9784358 |
| naturally occurring deletion mutants are parasitic genotypes in a wild-type nucleopolyhedrovirus population of spodoptera exigua | a wild-type nucleopolyhedrovirus (npv) isolate from spodoptera exigua from florida (se-us2) is a variant of the semnpv type strain since it has a unique dna profile but is closely related to other known geographical isolates of semnpv. it consists of several genotypic variants, of which seven were identified in a se-us2 virus stock by a modification of the in vivo cloning method developed by smith and crook (virology 166:240-244, 1988). the us2a variant was the most prevalent genotype, and it wa ... | 1998 | 9797293 |
| toxicity and receptor binding properties of a bacillus thuringiensis cryic toxin active against both lepidoptera and diptera. | this study describes an investigation into the relationship among toxicity, specificity, and binding of cryic delta-endotoxin from bacillus thuringiensis subspecies aizawai hd-229. in vivo bioassays of larvae using inclusions (aedes aegypti) or solubilized toxin (spodoptera littoralis, spodoptera exigua, spodoptera frugiperda, and manduca sexta) revealed that cryic was toxic to both dipteran and lepidopteran larvae. in vitro saturation binding assays with cryic toxin labeled in vivo with [35s]me ... | 1999 | 9878290 |
| toxicity, binding, and permeability analyses of four bacillus thuringiensis cry1 delta-endotoxins using brush border membrane vesicles of spodoptera exigua and spodoptera frugiperda. | the binding and pore formation properties of four bacillus thuringiensis cry1 toxins were analyzed by using brush border membrane vesicles from spodoptera exigua and spodoptera frugiperda, and the results were compared to the results of toxicity bioassays. cry1fa was highly toxic and cry1ac was nontoxic to s. exigua and s. frugiperda larvae, while cry1ca was highly toxic to s. exigua and weakly toxic to s. frugiperda. in contrast, cry1bb was active against s. frugiperda but only marginally activ ... | 1999 | 9925568 |
| overexpression of the bacillus thuringiensis (bt) cry2aa2 protein in chloroplasts confers resistance to plants against susceptible and bt-resistant insects. | evolving levels of resistance in insects to the bioinsecticide bacillus thuringiensis (bt) can be dramatically reduced through the genetic engineering of chloroplasts in plants. when transgenic tobacco leaves expressing cry2aa2 protoxin in chloroplasts were fed to susceptible, cry1a-resistant (20,000- to 40,000-fold) and cry2aa2-resistant (330- to 393-fold) tobacco budworm heliothis virescens, cotton bollworm helicoverpa zea, and the beet armyworm spodoptera exigua, 100% mortality was observed a ... | 1999 | 10051556 |
| microsporidian intrasporal sugars and their role in germination. | the hypothesis that spores of terrestrial and aquatic microsporidia differ in their utilization of sugars was tested by evaluating the sugars in germinated and ungerminated spores of several species in each category. the aquatic species tested were vavraia culicis, edhazardia aedis, and nosema algerae and the terrestrial species were vairimorpha necatrix, nosema disstriae, nosema apis, vairimorpha lymantriae, and nosema spp. from spodoptera exigua and plutella xylostella. the percentage germinat ... | 1999 | 10222184 |
| coinfection of spodoptera exigua and spodoptera frugiperda cell lines with the nuclear polyhedrosis viruses of autographa californica and spodoptera exigua. | the autographa californica multinucleocapsid nuclear polyhedrosis virus (acmnpv) has a broad host range among lepidoptera. in contrast, the spodoptera exigua mnpv (semnpv) can replicate efficiently only in s. exigua larvae or s. exigua-derived cell lines. in this study, we examined the coinfection of s. exigua se301 and spodoptera frugiperda iplb-sf21aeii (sf21) cell lines with semnpv and acmnpv recombinant (ac360-501beta-gal) which was constructed for expression of beta-galactosidase under cont ... | 1998 | 10325534 |
| replication of spodoptera exigua nucleopolyhedrovirus in permissive and non-permissive lepidopteran cell lines. | the spodoptera exigua multinucleocapsid nucleopolyhedrovirus (semnpv) was inoculated to eight lepidopteran cell lines derived from spodoptera exigua (se301), spodoptera frugiperda (sf21aeii), spodoptera littoralis (cls-79), spodoptera litura (spli-221), pseudaletia separata (lese-11), trichoplusia ni (hi-5), plutella xylostella (pxl/c) and bombyx mori (bmn4). the productive infection of semnpv was observed only in se301 cells. however, a dot-blot hybridization analysis revealed that semnpv dna r ... | 1998 | 10358729 |
| development and field performance of a broad-spectrum nonviable asporogenic recombinant strain of bacillus thuringiensis with greater potency and uv resistance. | the main problems with bacillus thuringiensis products for pest control are their often narrow activity spectrum, high sensitivity to uv degradation, and low cost effectiveness (high potency required). we constructed a sporulation-deficient sigk(-) b. thuringiensis strain that expressed a chimeric cry1c/ab gene, the product of which had high activity against various lepidopteran pests, including spodoptera littoralis (egyptian cotton leaf worm) and spodoptera exigua (lesser [beet] armyworm), whi ... | 1999 | 10473413 |
| identification of bacillus thuringiensis delta-endotoxin cry1c domain iii amino acid residues involved in insect specificity. | cry1c domain iii amino acid residues involved in specificity for beet armyworm (spodoptera exigua) were identified. for this purpose, intradomain iii hybrids between cry1e (nontoxic) and cry1e-cry1c hybrid g27 (toxic) were made. crossover points of these hybrids defined six sequence blocks containing between 1 and 19 of the amino acid differences between cry1e and g27. blocks b, c, d, and e of g27 were shown to be required for optimal activity against s. exigua. block e was also required for opt ... | 1999 | 10508062 |
| characterization of a nucleopolyhedrovirus from the black cutworm, agrotis ipsilon (lepidoptera: noctuidae) | the black cutworm, agrotis ipsilon (hufnagel) (lepidoptera: noctuidae), is a serious localized pest of vegetable and field crops. we have characterized a newly discovered baculovirus, the agrotis ipsilon multicapsid nucleopolyhedrovirus (agipmnpv), that was isolated from a. ipsilon in illinois. restriction enzyme fragment profiles of agipmnpv dna were distinct from those of previously described nucleopolyhedroviruses. electron microscopy of agipmnpv-infected tissues indicated that nucleocapsids ... | 1999 | 10534417 |
| sequence and organization of the spodoptera exigua multicapsid nucleopolyhedrovirus genome. | the nucleotide sequence of the dna genome of spodoptera exigua multicapsid nucleopolyhedrovirus (semnpv), a group ii npv, was determined and analysed. the genome contains 135611 bp and has a g+c content of 44 mol%. computer-assisted analysis revealed 139 orfs of 150 nucleotides or larger; 103 have homologues in autographa californica mnpv (acmnpv) and a further 16 have homologues in other baculoviruses. twenty orfs are unique to semnpv. major differences in semnpv gene content and arrangement we ... | 1999 | 10567663 |
| infectivity studies of a new baculovirus isolate for the control of the diamondback moth (plutellidae: lepidoptera). | this study describes a new baculovirus isolate recovered from infected larvae of the diamondback moth, plutella xylostella (l.), and identified as a multiple nucleopolyhedrovirus (mnpv). the plaque purified isolate designated as pxmnpvcl3 was found to be pathogenic to p. xylostella, heliothis virescens (f.), trichoplusia ni (hübner), h. subflexa (guenée), helicoverpa zea (boddie), spodoptera exigua (hübner), and s. frugiperda (j. e. smith) larvae in decreasing order of susceptibility. the lc50 f ... | 1999 | 10582047 |
| development of a novel expression vector system using spodoptera exigua nucleopolyhedrovirus. | to develop a novel spodoptera exigua nucleopolyhedrovirus (senpv) expression vector system, we examined characteristics of the senpv polyhedrin expression in s. exigua cells (se301). while the extracellular virus titer of senpv was 100-fold lower than that of autographa californica nucleopolyhedrovirus (acnpv), the levels of polyhedral inclusion body (pib) formation and polyhedrin expression were higher in senpv. to investigate foreign gene expression under the control of the polyhedrin promoter ... | 1999 | 10597039 |
| biological activity of semnpv, acmnpv, and three acmnpv deletion mutants against spodoptera exigua larvae (lepidoptera: noctuidae). | virulence and speed of action, as related to dose, are important effectiveness-determining properties of insect-pathogenic biocontrol agents. we used the droplet-feeding bioassay to compare dose responses between two wild-type baculoviruses, autographa californica multicapsid nucleopolyhedrovirus (acmnpv) and spodoptera exigua mnpv (semnpv), and three deletion mutants of acmnpv in s. exigua larvae. in each mutant one gene was deleted by genetic engineering: pp34, coding for the polyhedral membra ... | 2000 | 10631054 |
| characterization of recombinant mustard trypsin inhibitor 2 (mti2) expressed in pichia pastoris. | the mustard trypsin inhibitor mti2 was expressed as secretory protein in the yeast pichia pastoris. in order to evaluate the influence of the c-terminal amino acids of the precursor form on the inhibitor activity, the c-terminal precursor and the mature protein were both expressed. a third his-tagged construct was also designed to compare alternative purification procedures. proteins were efficiently expressed at levels of 40-160 mg/l in shake flasks. equilibrium dissociation constants demonstra ... | 2000 | 10692574 |
| bacillus thuringiensis delta-endotoxin cry1c domain iii can function as a specificity determinant for spodoptera exigua in different, but not all, cry1-cry1c hybrids. | in order to test our hypothesis that bacillus thuringiensis delta-endotoxin cry1ca domain iii functions as a determinant of specificity for spodoptera exigua, regardless of the origins of domains i and ii, we have constructed by cloning and in vivo recombination a collection of hybrid proteins containing domains i and ii of various cry1 toxins combined with domain iii of cry1ca. cry1ab, cry1ac, cry1ba, cry1ea, and cry1fa all become more active against s. exigua when their domain iii is replaced ... | 2000 | 10742242 |
| comparative analysis of the binding of antibodies prepared against the insect spodoptera exigua and against the mycopathogen nomuraea rileyi. | polyclonal antibodies were produced in mice against spodoptera exigua (beet armyworm) larval hemolymph and hemocytes and against cell wall surfaces of hyphal bodies and hyphae of the entomopathogenic hyphomycete nomuraea rileyi. in addition to exhibiting strong activity against their original antigenic substrates, all of the antibodies cross-react extensively with other substrates. the hemolymph antibody binds to hemocytes and vice versa, and both antibodies cross-react to the insect fat body ba ... | 2000 | 10772323 |
| expression of the green fluorescent protein carried by autographa californica multiple nucleopolyhedrovirus in insect cell lines. | a recombinant acmnpv containing the green fluorescent protein (gfp) gene under the polyhedrin promoter (polh) was used to investigate the expression of the gfp gene as well as the production of recombinant extracellular virus in 14 continuous insect cell lines, including heliothis virescens (bcirl-hv-am1), helicoverpa zea (bcirl-hz-am1), anticarsia gemmatalis (bcirl-ag-am1), trichoplusia ni (tn-cl1), spodoptera frugiperda (iplb-sf21), spodoptera exigua (bcirl/amcy-se-e1 and bcirl/amcy-se-e5), bo ... | 2000 | 10777062 |
| involvement of jasmonate- and salicylate-related signaling pathways for the production of specific herbivore-induced volatiles in plants. | we compared volatiles from lima bean leaves (phaseolus lunatus) infested by either beet armyworm (spodoptera exigua), common armyworm [mythimna (pseudaletia) separata], or two-spotted spider mite (tetranychus urticae). we also analyzed volatiles from the leaves treated with jasmonic acid (ja) and/or methyl salicylate (mesa). the volatiles induced by aqueous ja treatment were qualitatively and quantitatively similar to those induced by s. exigua or m. separata damage. furthermore, both s. exigua ... | 2000 | 10845451 |
| four genotypic variants of a spodoptera exigua nucleopolyhedrovirus (se-sp2) are distinguishable by a hypervariable genomic region. | four genotypes named sp2a, sp2b, sp2c and sp2d were obtained in vivo by infecting s. exigua larvae with limiting dilutions of the spanish field isolate spodoptera exigua nucleopolyhedrovirus (se-sp2) of semnpv. the cloning of variants sp2a, sp2b and sp2c took 1, 6, and 3 passages, respectively, before the dna profiles showed all bands in equimolar concentrations, and they remained constant for at least six further passages indicating the stability of their genotypes. the sp2d variant isolation t ... | 1999 | 10854166 |
| relationships between polydnavirus gene expression and host range of the parasitoid wasp campoletis sonorensis. | to evaluate the relationship between immune suppression and host range six lepidopteran species were parasitized by the ichneumonid parasitoid campoletis sonorensis. parasitism inhibited the growth of permissive hosts (heliothis virescens, helicoverpa zea, and trichoplusia ni), whereas growth of semi-permissive (spodoptera exigua, agrotis ipsilon) and non-permissive hosts (manduca sexta) was not significantly affected. the 29-36 kda ovarian protein (op), responsible for transient immunosuppressi ... | 2000 | 10878266 |
| eicosanoids rescue spodoptera exigua infected with xenorhabdus nematophilus, the symbiotic bacteria to the entomopathogenic nematode steinernema carpocapsae. | xenorhabdus nematophilus is a pathogenic bacterium causing insect haemolymph septicemia, which leads to host insect death. to address the fundamental mechanisms underlying this haemolymph septicemia, or the immunodepressive response of the host insects following bacterial infection, we tested a hypothesis that the insect immune-mediating eicosanoid pathway is blocked by inhibitory action of the bacterium. haemocoelic injection of the bacteria into the fifth instar larvae of spodoptera exigua red ... | 2000 | 10891575 |
| enhancement in activity of homologous and heterologous baculoviruses infectious to beet armyworm (lepidoptera: noctuidae) by an optical brightener. | the nuclear polyhedrosis virus (npv) from the beet armyworm, spodoptera exigua (hübner) (semnpv), was the most active virus tested against the beet armyworm (lc50 = 4.1 pibs/mm2), followed by nuclear polyhedrosis viruses from the alfalfa looper, autographa californica (speyer) (acmnpv; lc50 = 92.6 pibs/mm2), and the celery looper, anagrapha falcifera (kirby) (afmnpv; lc50 = 195.7 pibs/mm2). in the case of the nuclear polyhedrosis virus from the bollworm, helicoverpa armigera (hübner), lc50s coul ... | 2000 | 10902301 |
| isolation of a spodoptera exigua baculovirus recombinant with a 10.6 kbp genome deletion that retains biological activity. | when spodoptera exigua multicapsid nucleopolyhedrovirus (semnpv) is grown in insect cell culture, defective viruses are generated. these viruses lack about 25 kbp of sequence information and are no longer infectious for insects. this makes the engineering of semnpv for improved insecticidal activity or as expression vectors difficult to achieve. recombinants of autographa californica mnpv have been generated in insects after lipofection with viral dna and a transfer vector into the haemocoel. in ... | 2000 | 10993945 |
| molecular genetic manipulation of truncated cry1c protein synthesis in bacillus thuringiensis to improve stability and yield. | cry1 protoxins of bacillus thuringiensis are insecticidal 135-kda proteins synthesized and assembled into parasporal crystals during sporulation. after ingestion, these crystals dissolve in the midgut and active toxins with molecular masses of about 65-kda are released from the n-terminal half of the molecule by midgut proteases. direct synthesis of the toxin-containing n-terminal half of cry1 molecules using recombinant dna techniques results in a low level of unstable truncated proteins that d ... | 2000 | 11010897 |
| a novel baculovirus envelope fusion protein with a proprotein convertase cleavage site. | the entry mechanism of spodoptera exigua multicapsid nucleopolyhedrovirus (semnpv), a group ii npv, in cultured cells was examined. semnpv budded virus (bv) enters by endocytosis as do the bvs of the group i npvs, autographa californica (ac) mnpv and orgyia pseudotsugata (op) mnpv. in group i npvs, upon infection acidification of the endosome triggers fusion of the viral and endosomal membrane, which is mediated by the bv envelope glycoprotein gp64. however, the semnpv genome lacks a homolog of ... | 2000 | 11017785 |
| gut bacteria may be involved in interactions between plants, herbivores and their predators: microbial biosynthesis of n-acylglutamine surfactants as elicitors of plant volatiles. | n-acylamino acids are dominant and widespread constituents of insect oral secretions (regurgitants), serving the insect as biosurfactants in the digestive process. during feeding the conjugates may be introduced into damaged leaves and contribute there to the elicitation of plant defenses such as the induction of volatile biosynthesis. from gut segments of spodoptera exigua, mamestra brassicae and agrotis segetum 23 bacterial strains were isolated, ten of which were able to synthesise typical le ... | 2000 | 11030433 |
| adaptation of spodoptera exigua (lepidoptera: noctuidae) to barley trypsin inhibitor bti-cme expressed in transgenic tobacco. | nicotiana tabacum plants were transformed with the cdna of barley trypsin inhibitor bti-cme under the control of the 35s camv promoter. although the transgene was expressed and the protein was active in the homozygous lines selected, growth of spodoptera exigua (lepidoptera: noctuidae) larvae reared on transgenic plants was not affected. the protease activity in larval midgut extracts after 2 days feeding on transformed tobacco leaves from the highest expressing plant showed a reduction of 25% i ... | 2000 | 11032365 |
| a new ascovirus from spodoptera exigua and its relatedness to the isolate from spodoptera frugiperda. | a new ascovirus was isolated from spodoptera exigua in indonesia and was tentatively assigned as a new species, spodoptera exigua ascovirus 5a (seav-5a) according to the present ictv ascovirus naming scheme based on dna restriction fragment length polymorphism (rflp), hybridization, formation of occlusion body, tissue tropism and host spectrum. seav-5a replicated primarily in the fat body of susceptible hosts. seav-5a could be transmitted to s. frugiperda, pseudoplusia includens and trichoplusia ... | 2000 | 11086139 |