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  • Electronic Resource  (11)
  • Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry  (6)
  • Evolution  (5)
  • 1
    ISSN: 1432-1432
    Keywords: Cyanelles ; Cyanophora paradoxa ; Endosymbiosis ; Evolution ; Glaucocystophyta ; Glaucophyta ; Phylogeny ; Plastid ; 16S ribosomal RNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Glaucocystophyte algae (sensu Kies, Berl. Deutsch. Bot. Ges. 92, 1979) contain plastids (cyanelles) that retain the peptidoglycan wall of the putative cyanobacterial endosymbiont; this and other ultrastructural characters (e.g., unstacked thylakoids, phycobilisomes) have suggested that cyanelles are “primitive” plastids that may represent undeveloped associations between heterotrophic “host” cells (i.e., glaucocystophytes) and cyanobacteria. To test the monophyly of glaucocystophyte cyanelles and to determine their evolutionary relationship to other plastids, complete 16S ribosomal RNA sequences were determined for Cyanophora paradoxa, Glaucocystis nostochinearum, Glaucosphaera vacuolata, and Gloeochaete wittrockiana. Plastid rRNAs were analyzed with the maximum-likelihood, maximumparsimony, and neighbor joining methods. The phylogenetic analyses show that the cyanelles of C. paradoxa, G. nostochinearum, and G. wittrockiana form a distinct evolutionary lineage; these cyanelles presumably share a monophyletic origin. The rDNA sequence of G. vacuolata was positioned within the nongreen plastid lineage. This result is consistent with analyses of nuclear-encoded rRNAs that identify G. vacuolata as a rhodophyte and support its removal from the Glaucocystophyta. Results of a global search with the maximumlikelihood method suggest that cyanelles are the first divergence among all plastids; this result is consistent with a single loss of the peptidoglycan wall in plastids after the divergence of the cyanelles. User-defined tree analyses with the maximum-likelihood method indicate, however, that the position of the cyanelles is not stable within the rRNA phylogenies. Both maximumparsimony and neighbor-joining analyses showed a close evolutionary relationship between cyanelles and nongreen plastids; these phylogenetic methods were sensitive to inclusion/exclusion of the G. wittrockiana cyanelle sequence. Base compositional bias within the G. wittrockiana 16S rRNA may explain this result. Taken together the phylogenetic analyses are interpreted as supporting a near-simultaneous radiation of cyanelles and green and nongreen plastids; these organelles are all rooted within the cyanobacteria.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1432-0819
    Keywords: Zoned magma body ; Chemical variation ash-flow sheets ; Tephra sequence ; Differentiation time constraints ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract The Rainier Mesa ash-flow is a large (1200 km3), 11.6 My old, chemically zoned unit that ranges in composition from 55 to 76% SiO2 — one of the largest chemical ranges ever observed in a large volume ash-flow sheet. Two chemical trends occur in this sheet, a low silica (55–66% SiO2) and a high silica (〉66% SiO2) trend. Ninety per cent of the Rainier Mesa sheet occurs in the high silica trend. Immediately beneath the Rainier Mesa sheet is a thick tephra sequence. The chemical variation of this sequence is nearly equivalent to the high silica portion of the Rainier Mesa ash-flow sheet (about 66–78% SiO2). Throughout the tephra sequence numerous small ash-flow layers occur, and each ash-flow layer is chemically zoned from more evolved at the base to less evolved at the top. This is consistent with having been erupted from a zoned magma body. The lowest silica tephra units are at the base of the sequence and the highest silica units are at the top — that is, the large-scale chemical trend of the entire sequence is opposite to that of the individual ash-flow layers. These ash-flow layers are of very small volume. The tephra sequence provides a unique record of the incremental development of the zoned, high silica portion of the Rainier Mesa magma body.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-0819
    Keywords: Key wordsZoned magma body ; Chemical variation ; ash-flow sheets ; Tephra sequence ; Differentiation ; time constraints ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract The Rainier Mesa ash-flow is a large (1200 km3), 11.6 My old, chemically zoned unit that ranges in composition from 55 to 76% SiO2– one of the largest chemical ranges ever observed in a large volume ash-flow sheet. Two chemical trends occur in this sheet, a low silica (55–66% SiO2) and a high silica (〉66% SiO2) trend. Ninety per cent of the Rainier Mesa sheet occurs in the high silica trend. Immediately beneath the Rainier Mesa sheet is a thick tephra sequence. The chemical variation of this sequence is nearly equivalent to the high silica portion of the Rainier Mesa ash-flow sheet (about 66–78% SiO2). Throughout the tephra sequence numerous small ash-flow layers occur, and each ash-flow layer is chemically zoned from more evolved at the base to less evolved at the top. This is consistent with having been erupted from a zoned magma body. The lowest silica tephra units are at the base of the sequence and the highest silica units are at the top – that is, the large-scale chemical trend of the entire sequence is opposite to that of the individual ash-flow layers. These ash-flow layers are of very small volume. The tephra sequence provides a unique record of the incremental development of the zoned, high silica portion of the Rainier Mesa magma body.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-072X
    Keywords: Eubacterium ; Thermophile ; Evolution ; Fervidobacterium ; Lipids ; Thermotoga
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An extremely thermophilic anaerobic fermentative eubacterium growing at temperatures between 50 and 80°C (opt.: 65°C) was isolated from an Icelandic hot spring. The cells were Gram-negative motile rods, about 1.8 μm in length, and 0.6 μm in width occurring singly and in pairs. About 50% of the cells formed large spheroids at one end similar to Fervidobacterium nodosum. The new isolate H 21 differed from Fervidobacterium nodosum by a 6 mol % higher GC-content of its DNA (41 mol %), its ability to grow on cellulose, and insignificant DNA homology. The lipids of isolate H 21 were similar to that of members of “Thermotogales”. 16S rRNA sequencing of isolate H 21 and Fervidobacterium nodosum indicated (a) that isolate H 21 represents a new species of the genus Fervidobacterium which we name Fervidobacterium islandicum and (b) that the genus Fervidobacterium belongs to the “Thermotogales” branch.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-072X
    Keywords: Evolution ; Eubacteria ; Thermophile ; Anaerobe ; Thermotoga maritima
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A novel type of bacterium has been isolated from various geothermally heated locales on the sea floor. The organisms are strictly anaerobic, rod-shaped, fermentative, extremely thermophilic and grow between 55 and 90°C with an optimum of around 80°C. Cells show a unique sheath-like structure and monotrichous flagellation. By 16S rRNA sequencing they clearly belong to the eubacteria, although no close relationship to any known group could be detected. The majority of their lipids appear to be unique in structure among the eubacteria. Isolate MSB8 is described as Thermotoga maritima, representing the new genus Thermotoga.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Archives of Insect Biochemistry and Physiology 10 (1989), S. 281-291 
    ISSN: 0739-4462
    Keywords: antennal lobe ; electrophysiology ; olfaction ; Chemistry ; Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Recently, chemical analysis of solvent rinses of the external surfaces of pheromone glands from female Manduca sexta revealed a blend of 12 aldehydes, including the previously identified sex pheromone component, (E,Z)-10,12-hexadecadienal (bombykal). Previous electrophysiological studies showed that olfactory (deutocerebral) interneurons in the antennal lobes of males exhibited a wide range of responsiveness to pheromonal stimulation of the ipsilateral antenna. These experiments were performed with crude extracts of pheromone glands as well as two synthetic compounds: the major pheromone component, bombykal, and (E,Z)-11,13-pentadecadienal, a mimic of a second component of the female's pheromone blend. Using intracellular methods, we have now reexamined similar olfactory interneurons, using each of the 12 chemically identified components as well as synthetic blends of various combinations of them. Eight of the 12 components isolated from female glands elicited some form of response in olfactory interneurons in males. In accordance with biochemical and behavioral data, the most potent are bombykal and two trienals, (E,E,E)- and (E,E,Z)-10,12,14-hexadecatrienal. We also conclude that the C15 dienal is selective for one of the trienal receptors on the antenna, but is much less potent than the natural trienal stimulant.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Archives of Insect Biochemistry and Physiology 26 (1994), S. 97-109 
    ISSN: 0739-4462
    Keywords: Hymenoptera ; venom ; host hemolymph ; plasma proteins ; regulation ; Chemistry ; Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Investigations were conducted to determine the titer of storage proteins in larvae of the cabbage looper, Trichoplusia ni (Hübner), that were parasitized by the ectoparasitoid Euplectrus comstockii Howard (Hymenoptera: Eulophidae). A gradual increase was noted in the titer of the storage proteins present in the hemolymph of parasitized third and fourth instar larvae and in the hemolymph of isolated thoracic and abdominal tissues of fourth instar larvae. The final amount present in parasitized third and fourth instar larvae was similar to that found in nonparasitized fifth instar larvae. The stimulation of storage proteins in envenomed larvae demonstrates the ability (competence) of early larval stages to produce a gene product that normally occurs in the last larval stadium of the lepidopteran larval host. The gene expression necessary for storage protein production in isolated tissues may be altered by mechanisms separate from inherent developmental processes and the intact endocrine system. © 1994 Wiley-Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Archives of Insect Biochemistry and Physiology 3 (1986), S. 1-2 
    ISSN: 0739-4462
    Keywords: Chemistry ; Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Archives of Insect Biochemistry and Physiology 13 (1990), S. 83-94 
    ISSN: 0739-4462
    Keywords: molt arrest ; 20-hydroxyecdysone ; juvenile hormone ; methoprene ; Chemistry ; Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Parasitism by Euplectrus plathypenae inhibits larval-larval ecdysis in Trichoplusia ni by injecting nonparalytic factor(s) into the host during the stinging process via the parasitoid's ovipositor. The parasitized host moves freely, feeds, and gains weight prior to the time of the normal ecdysis but does not molt. Parasitoid development is not required for the expression of molt arrest in the host. Parasitism during the first three fourths of the larval stadium results in molt arrest. Arrestment of molting is independent of 20-hydroxyecdysone and juvenile hormone. The arrestment factor(s) affect the epidermal tissue of the thorax and abdomen in ligated hosts without apparent interaction from other areas of the body. Cuticle and epidermal tissue of parasitized insects do not show signs of apolysis or ecdysis.
    Additional Material: 2 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Archives of Insect Biochemistry and Physiology 21 (1992), S. 1-11 
    ISSN: 0739-4462
    Keywords: hemolymph proteins ; diapause protein ; larval diapause ; Chemistry ; Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A diapause associated protein was electrophoretically isolated from the hemolymph of diapausing last instar larvae of the pink bollworm Pectinophora gossypiella. This protein (Mr ∼490,000, glycolipoprotein) was given the name Pectinophora diapause protein (PDP). It is composed of one subunit (Mr 103,000). The concentration of PDP increased dramatically in the hemolymph of diapausing larvae from 17.4% in prediapause (PD) phase to 29.2% in early diapause (ED) phase reaching a level of 38.6% in larval hemolymph of middiapause (MD) phase. The concentrations of total proteins in the hemolymph of active feeding (A), PD, ED, and MD larvae were 69.8, 106.6, 113.3, and 118 mg/ml, respectively, while those in the fat body of the same larvae were 7.1, 7.4, 8.8, and 4.5 mg/g, respectively. In Pectinophora a drop in the concentration of fat body proteins coincided with a corresponding increase in hemolymph proteins, which suggests an active release of protein from the fat body into the hemolymph during the development of diapause. A partial amino acid sequence of pectinophorin showed the first 15 amino acids starting from the amino terminus of the peptide chain: N-ALA-LYS-THR-ILEU-VAL-GLU-ASN-MET-PRO-PRO-THR-PRO-LEU-ASN-ALA-C. © 1992 Wiley-Liss, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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