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  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 32 (1985), S. 0 
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: A new species of the uncommon microsporidian genus Telomyxa (Microspora: Telomyxidae) has been found parasitizing the larval fat body of the semiaquatic beetle, Ora texana. In this species, the sporogonic sequence results in the formation of sporocysts measuring 7.7 times 6.5 μm that contain two crested uninucleate spores (averaging 5.7 times 2.2 μm). The spores are essentially oblong/ovate, tapering toward the anterior end and remaining bound together after sporogony by a persistent accessory membrane or sporocyst. The two spores in the sporocyst are produced by an unusual morphogenetic sequence in which, after one mitosis, the binucleate sporont elongates, forming two lobes that fold toward one another and cleave along a central plane, forming two parallel sporoblasts. The general ultrastructural features of this process are described, and diagnostic characters of this new species of Telomyxa are presented.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1573-8248
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Résumé Des rendements élevés en copépodes,Cyclops vernalis infectés par le champignon parasite des moustiques,Coelomomyces dodgei Couch & Dodge ont été obtenus en contaminant les nauplii de populations importantes se développant de façon synchrone. L’exposition pendant 48 ou 72 h de 2 000 nauplii âgés à 6.103 sporanges au stade d’émission des méiospores produit environ 1 500 copépodes infectés. Le taux de copépodes infectés, c’est-à-dire la sensibilité deC. vernalis au champignon, décroit avec le développement du crustacé. Ces taux sont de 75% dans le cas de nauplii âgés et de 32 et 9,6% respectivement dans le cas de copépodides ou d’adultes. Les conséquences de ces résultats, pour la multiplication d’autres espèces deCoelomomyces et les essais sur leur activité à l’égard des organismes non visés, sont discutées. Un procédé amélioré de production de routine deC. dodgei est décrit.
    Notes: Abstract High yields of the copepodCyclops vernalis infected with the mosquito-parasitic fungusCoelomomyces dodgei Couch & Dodge were obtained by infecting nauplii in large synchronously developing populations. Exposure of 2000 48 or 72 h old nauplii to 6×103 sporangia at the time of meiospore release yielded ca. 1500 infected copepods. Based on yields of infected copepods, susceptibility ofC. vernalis toC. dodgei decreased as copepods developed. Infection rates were 75% for copepods exposed as 48 or 72 h old nauplii but declined to 32 and 9.6%, respectively, for those exposed as copepodids or adults. The relevance of these results for domestication of other species ofCoelomomyces and studies on non-target organisms is discussed, and improved procedures for routine production ofC. dodgei are described.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-8798
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary. A multinucleocapsid nuclear polyhedrosis virus (MNPV) isolated from the celery looper, Anagrapha falcifera, has been proposed as a new virus based on differences in virulence and DNA fragment profiles between this isolate and the Autographa californica MNPV, the MNPV type species. In the present study, we examined the relatedness of the AfMNPV and AcMNPV genomes by (1) Southern hybridization, (2) comparison of their genetic organization in the polyhedrin gene region (AcMNPV EcoRI-I fragment), and (3) comparison of the nucleotide and deduced amino acid sequences of eight viral genes in this region. Both DNAs hybridized strongly to one another in reciprocal hybridization experiments under stringent conditions, and physical mapping showed that gene order was conserved between the two viruses in the polyhedrin gene region, though the ORF 984 and ctl genes were absent from this region in the AfMNPV. Gene and deduced amino acid sequences for p78, protein tyrosine phospatase, protein kinase, lef-2, and ORFs 327, 453 and 603, showed identity between the two viruses of greater than 91%. The sequences for the gp64 gene, located on a different EcoRI fragment, were also compared and had a nucleotide sequence identity of 97%, and amino acid sequence identity of greater than 98%. The polyhedrin gene showed the least relatedness between the two viruses, with a nucleotide sequence identity of 80%, and a deduced amino acid sequence identity of 90%. Based on these results, we conclude that the AfMNPV should be considered a variant of the AcMNPV. These results also indicate that caution must be used in basing phylogenetic relationships of NPVs on analysis of a single gene, especially the polyhedrin gene, as is the current practice.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Archives of virology 145 (2000), S. 1933-1945 
    ISSN: 1432-8798
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary.  Well over 100 isolates of granulosis viruses (GVs), genus Granulovirus (family Baculoviridae), have been reported, all from lepidopterous insects. Three types of GVs are recognized, those of Type 1, which attack the fat body, Type 2, which attack most tissues, and Type 3, which attack only the midgut epithelium. To determine whether a correlation exists between tissue tropism and lepidopteran family phylogeny, the granulin gene of the Harrisina brillians (HbGV), a virus that attacks the midgut epithelium of H. brillians (family Zygaenidae) was cloned, sequenced, characterized, and compared with granulin genes of GVs that attack species of Tortricidae, Pieridae, and Noctuidae. The HbGV granulin gene encoded a peptide of 248 amino acids with a predicted Mr of 29.6 kDa, and shared a significant level of homology with other granulin (81–95% identical and 90–98% similar) and polyhedrin (49–58% identical and 62–72% similar) proteins. Phylogenetic analyses based on granulin and polyhedrin genes as well as on their 5′-untranslated sequences (5′-UTSs) indicated that HbGV was more closely related to GVs isolated from the tortricids, Cryptophlebia leucotreta (ClGV), Cydia pomonella (CpGV) and Choristoneura fumiferana (CfGV) than to other GVs and NPVs. This analysis provides preliminary evidence for a correlation between GV tissue tropism and the phylogeny of lepidopteran families, suggesting that GVs attacking species of Tortricidae and Zygaenidae are ancestral to those attacking species of the family Noctudiae.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract 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. thuringiensis transformed with this plasmid, designated pWF53, produced large bitrapezoidal CryIVD crystals that averaged 1.3 × 0.92 × 0.31 μm, approximately fivefold larger in volume than wild-type CryIVD crystals, and 1.7 fold the volume of crystals produced using the cryIV D operon, which contains the cryIV D gene and the gene for the 20-kDa protein. These results demonstrate that the 20-kDa protein significantly improves net synthesis of CryIVD and promotes CryIVD crystal formation. Improved production of proteins as diverse as CryIVD and CytA by the 20-kDa protein indicates this protein may be useful in facilitating the production of other proteins.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  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. thuringiensis transformed with this plasmid, designated pWF53, produced large bitrapezoidal CryIVD crystals that averaged 1.3×0.92×0.31 μm, approximately fivefold larger in volume than wild-type CryIVD crystals, and 1.7 fold the volume of crystals produced using the cryIVD operon, which contains the cryIVD gene and the gene for the 20-kDa protein. These results demonstrate that the 20-kDa protein significantly improves net synthesis of CryIVD and promotes CryIVD crystal formation. Improved production of proteins as diverse as CryIVD and CytA by the 20-kDa protein indicates this protein may be useful in facilitating the production of other proteins.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 19 (1993), S. 2485-2499 
    ISSN: 1573-1561
    Keywords: Bacillus thuringiensis subsp.kurstaki strain HD-73 ; insecticidal proteins ; cotton condensed tannin ; Heliothis virescens ; Lepidoptera ; Noctuidae ; relative growth rate ; relative consumption rate ; bioassays ; Gossypium hirsutum ; tritrophic interactions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The potential interactions among a plant-produced allelochemical, a phytophagous insect, and an endotoxin produced byBacillus thuringiensis were investigated using purified cotton condensed tannins, the CryIA(c)δ-endotoxin fromB. thuringiensis subsp.kurstaki strain HD-73, and larvae ofHeliothis virescens. Purified condensed tannin from cotton fed to neonateH. virescens reduced feeding and mortality caused by insecticidal crystals ofB. thuringiensis. In fifth instars, tannin reduced relative growth rate (RGR), relative consumption rate (RCR), but antagonized the effects of the crystalδ-endotoxin. Tannin did not deter feeding of fifth instars in choice tests with cellulose-ester disks. Masking tannin from interacting with the dietary ingredients of artificial diets and crystal protein by encapsulation in alginate gel suggested that tannin adversely affected feeding after ingestion.These results suggest that insect control tactics that employδ-endotoxins in microbial insecticides and transgenic cotton plants may not be compatible when used in conjunction with plants containing high tannin concentrations.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Protoplasma 121 (1984), S. 65-76 
    ISSN: 1615-6102
    Keywords: Blastocladiales ; Chytridiomycetes ; Coelomomyces ; Cytoplasmic cleavage ; Gametogenesis ; Mosquito-copepodpathogen ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The ultrastructure of gametogenesis was studied inCoelomomyces dodgei Couch (Blastocladiales, Chytridiomycetes), an obligate parasite of anopheline mosquito larvae and the copepod,Acanthocyclops vernalis. In infected copepods reared under a 16/8 hours light/dark photoperiod at 25 +2 °C., the gametophyte develops over a period of approximately seven days, and gametogenesis is triggered by the onset of the dark period during the last day of development. The initial step of gametogenesis is the elongation of the centriole to form the kinetosome, and measuring time from the onset of the final dark period (0 hours), this occurs prior to the beginning of the light period (8 hours). Subsequently, small vesicles that appear to originate from elements of the rough endoplasmic reticulum (rER) fuse at the distal end of the kinetosome forming the flagellar vesicle into which the axonemal microtubules elongate to form the flagellum (8–12 hours). Similar small vesicles apparently also derived from rER align in planes and fuse to form cleavage furrows which delineate the gamete initials (12–14 hours). As the gamete initials begin forming, the mitochondria within each initial fuse to form a single mitochondrion that associates with the lipid globules and microbodies forming the microbody-lipid globule complex (12–16 hours). The time elapsed between the formation of the flagellar vesicle to the release of mature gametes from the copepod host is about 8.5 hours. No differences were observed in the processes or timing of gametogenesis in male and female gametophytes.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Protoplasma 121 (1984), S. 77-86 
    ISSN: 1615-6102
    Keywords: Blastocladiales ; Coelomomyces ; Gametes ; Mosquitocopepod pathogen ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary As part of an investigation on the developmental biology ofCoelomomyces dodgei Couch (Blastocladiales, Chytridiomycetes), the ultrastructure of the male and female gametes was studied. The nucleus is central and conical in shape except for a basal spur that curves back towards the large plate-like mitochondrion. A nuclear cap of ribosomes sits on the flat anterior end of the nucleus. Approximately seven lipid globules are partially embedded in the mitochondrion and are interconnected by membrane cisternae. The lipid globules are covered by a single fenestrated microbody and a backing membrane lies between the microbody and the gamete plasma membrane. The kinetosome is at the base of the nucleus and is connected to a single, posterior, whiplash flagellum. A nonkinetosomal centriole is absent. In the peripheral cytoplasm of both mating types there is a paracrystalline body of unknown composition and function. No significant ultrastructural differences were found between the male and female gametes.
    Type of Medium: Electronic Resource
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