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Facet   Publication Year 1988  [X]
Facet   section ZfN Section C:Volume 043  [X]
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1988[X]
61Author    P. M. Abuja, I. PilzRequires cookie*
 Title    Investigation of Ribulose-1,5-bisphosphate Carboxylase-Oxygenase from Tobacco by Small Angle X-Ray Scattering: A Structural Model for the Enzyme in Solution  
 Abstract    The quaternary structure of ribulose-l,5-bisphosphate carboxylase/oxygenase from tobacco (Nicotiana tabacum) was investigated in solution by means of small angle X-ray scattering. The most important molecular parameters as the radius of gyration (Rg) and the maximum diameter (Dmax) were determined. Both the active and the inactive form of the enzyme were measured at 5 °C and at 20 °C. A more distinct difference in size could be detected between the inactive forms at these two temperatures (Rg = 4.80 nm (5 °C) and 4.68 nm (20 °C)) than between the active forms (Rg = 4.73 nm and 4.69 nm). The maximum diameters were determined to be 13.1 nm for the inactive form at 5 °C and 12.8 nm for the other forms. A model is proposed consisting of eight large and eight small subunits arranged in the way that seems to be typical for this enzyme in higher plants. 
  Reference    Z. Naturforsch. 43c, 373—376 (1988); received December 21 1987/February 15 1988 
  Published    1988 
  Keywords    Small-Angle X-Ray Scattering, Solution Structure, Ribulose-l, 5-bisphosphate Carboxylase/ Oxygenase, Conformational Change, Temperature Effect 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0373.pdf 
 Identifier    ZNC-1988-43c-0373 
 Volume    43 
62Author    Beate Klein, Hartmut FollmannRequires cookie*
 Title    Deoxyribonucleotide Biosynthesis in Green Algae. S Phase-Specific Thymidylate Kinase and Unspecific Nucleoside Diphosphate Kinase in Scenedesmus obliquus  
 Abstract    NDP kinase and thymidylate kinase are essential for DNA precursor formation in that they phosphorylate the products of de novo deoxyribonucleotide biosynthesis, deoxyribonucleoside 5'-diphosphates and thymidine 5'-monophosphate to the corresponding triphosphates which then serve as DNA polymerase substrates. The two enzymes have been measured in synchronous cultures of the green algae, S. obliquus. Thymidylate kinase exhibits an activity peak at the 11 —12th hour of the 24-hour cell cycle, coinciding with DNA synthesis. Enzyme activity is markedly stimulated in presence of fluorodeoxyuridine in the culture medium. This behaviour of dTMP kinase is very similar to that of three other S phase-specific peak enzymes previously analyzed in synchronous algae, viz. ribonucleotide reductase, thymidylate synthase, and dihydro-folate reductase. In contrast, NDP kinase exhibits high and constant activity through the entire cell cycle. The two kinases have been isolated from cell-free extracts, and separated from each other by chromatography on Blue Sepharose. The peak enzyme, dTMP kinase, has been purified to near homogeneity and its catalytic properties are described; the molecular weight is 56,000. NDP kinase activity is separable into two enzyme fractions, both of molecular weight 100,000 (or higher), which are unspecific with respect to ribonucleotide and deoxyribonucleotide substrates. Characterization and purification of the whole series of deoxyribonucleotide-synthesizing enzymes from one organism provides a basis for in vitro experiments towards reconstitution of an S phase-specific DNA precursor/DNA replication multien-».yme aggregate. 
  Reference    Z. Naturforsch. 43c, 377—385 (1988); received February 12/March 17 1988 
  Published    1988 
  Keywords    Algae, Cell Cycle, Deoxyribonucleotides, Nucleoside Diphosphate Kinase, Scenedesmus obliquus 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0377.pdf 
 Identifier    ZNC-1988-43c-0377 
 Volume    43 
63Author    Hans EcksteinRequires cookie*
 Title    Evidence for Cyclic GMP in the Yeast Saccharomyces cerevisiae, and Studies on Its Possible Role in Growth  
 Abstract    The yeast Saccharomyces cerevisiae is shown to be equipped with cyclic GMP, the level of which ranges from 6 pmol/10 9 cells with pressed baker's yeast to 21 pmol/10 9 cells with exponentially growing cells. In extracts from synchronized growing yeast, cyclic GMP increases stepwise, being doubled at the time of each mitosis. Theophylline and 3-isobutyl-l-methylxanthine induce a rapid increase of cyclic GMP, followed by a premature formation of the septal cell wall between mother cell and bud. The effects of 3-isobutyl-l-methylxanthine are reversible. Dibutyryl-cyclic GMP, and, after a pronounced lag, also dibutyryl-cyclic AMP, induce a premature cell division, too. Cholera toxin induces premature cell divisions without a preceding increase in cyclic GMP. Neither theophylline nor 3-isobutyl-l-methylxanthine, cholera toxin or one of the dibutyryl-cyclic nucleotides modify the growth rate of the culture. None of the agents has significant effects on the level of cyclic AMP. The results suggest that cyclic GMP possibly controls an early step of mitosis, whereas ADP-ribosylation might govern a subsequent event. 
  Reference    Z. Naturforsch. 43c, 386—396 (1988); received October 20 1987 
  Published    1988 
  Keywords    Cyclic GMP, Cyclic AMP, Phosphodiesterase Inhibitors, Cholera Toxin, Growth, Yeast 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0386.pdf 
 Identifier    ZNC-1988-43c-0386 
 Volume    43 
64Author    Kurt-Peter Raezke, Hermann Frister, Eckhard SchlimmeRequires cookie*
 Title    Ribosylierung mono-und bicyclischer Dicarbonsäureimide Ribosylation of Mono-and Bicyclic Dicarboxylic Acid Imides  
 Abstract    The N-trimethylsilyl compounds of the cyclic imides derived from c/s-cyclohexan-l,2-dicar-boxylic acid, cw-4-cyclohexen-l,2-dicarboxylic acid and phthalic acid were prepared. Reaction of the N-silylated cyclic imides 2 and 10 with 1,2,3,5-tetra-O-acetyl-ß-D-ribofuranose in the presence of tin tetrachloride yielded the appropriate unusual ribonucleosides 4 and 12 whereas 14 led only to traces of the ribosylated derivative. The silylation and ribosylation sites in the aforementioned bicyclic imides were proved by "H, 13 C, and 29 Si NMR spectroscopy and compared with data found for the monocyclic imides N-succinimide and N-maleinimide. 
  Reference    Z. Naturforsch. 43c, 397—402 (1988); received November 26 1987/February 9 1988 
  Published    1988 
  Keywords    Dicarboxylic Acid Imides, Lactam Systems, Silylation, Ribosylation, Ribonucleosides 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0397.pdf 
 Identifier    ZNC-1988-43c-0397 
 Volume    43 
65Author    Walter Maier, Brigitte Schumann, Detlef GrögerRequires cookie*
 Title    Effect of Chlorsulfuron, a Potent Inhibitor of Acetohydroxyacid Synthase, on Metabolism of Claviceps purpurea  
 Abstract    Chlorsulfuron, Claviceps purpurea, Alkaloid Pattern, Acetohydroxyacid Synthase Chlorsulfuron (CS) is a potent sulfonylurea herbicide inhibiting specifically acetohydroxyacid synthase which catalyzes the first step in the biosynthesis of branched-chain amino acids in plant cells, bacteria and yeast. The peptide portion of some ergot alkaloids contain inter alia branched-chain amino acids. The influence of CS on growth and alkaloid formation in Claviceps was studied. In an ergotoxine strain growth is inhibited by chlorsulfuron in the range of 10—100 UM. Under CS influence ergosine is accumulated besides ergotoxines. Growth inhibition caused by CS could be reversed by addition of L-valine (~ 35 mM), but neither by leucine nor isoleucine. Ergosine did not occur under these conditions. Acetohydroxyacid synthase (AHAS) from Claviceps purpurea was partially purified. AHAS preparations are not inhibited even by high concentrations of chlorsulfuron. 
  Reference    Z. Naturforsch. 43c, 403—407 (1988); received December 29 1987/February 12 1988 
  Published    1988 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0403.pdf 
 Identifier    ZNC-1988-43c-0403 
 Volume    43 
66Author    Anat Rozen, Mordechay Schönfeld, Elisha Tel-OrRequires cookie*
 Title    Fructose-Enhanced Development and Growth of the N 2 -Fixing Cyanobiont Anabaena azollae  
 Abstract    Fructose supported the heterotrophic growth of the cyanobiont Anabaena azollae, isolated from the water fern Azolla filiculoides, and also enhanced its growth in the light by 2-3-fold. Fructose was taken up at a high rate in the light and in the dark, in an energy-dependent reaction. The photosynthetic and respiratory activities of the fructose grown cells were modified: 0 2 evolu-tion in vivo was decreased by 40%, while PS I activity and dark respiration were 2-3-fold higher than in autotrophically grown cells. These changes were accompanied by 2-3-fold increase in heterocyst differentiation and by a 4-fold stimulation of nitrogenase activity. 
  Reference    Z. Naturforsch. 43c, 408—412 (1988); received February 1 1988 
  Published    1988 
  Keywords    Nitrogen Fixation, Symbiotic Cyanobacteria, Photosynthesis, Respiration, Heterotrophic Growth 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0408.pdf 
 Identifier    ZNC-1988-43c-0408 
 Volume    43 
67Author    Matthias Kuhn, Andreas Thiel, Peter BögerRequires cookie*
 Title    The 9-kDa Phosphoprotein Involved in Photoinhibition  
 Abstract    Photosystem-II particles exhibit strong photoinhibition. Short-term illumination of photosys-tem-II particles with high-intensity light (5000 piE/m 2 x s) leads to a typical change of the protein pattern on SDS-PAGE. Two proteins are mainly affected, namely the well-described 32-kDa herbicide-binding protein which probably is degraded [1] and, first published here, the 9-kDa phosphoprotein, whose function in the PS-II complex is still unknown. This protein is not de-graded, but seems to be linked to other polypeptides of the PS-II complex. During light treatment new bands of 23, 41, 50 and 54 kDa appear in the protein pattern of SDS-PAGE. A monospecific antiserum was produced against the 9-kDa phosphoprotein to investigate its fate. After light treatment the antibodies reacted with new proteins of higher molecular weights, most pronounced with a 23-kDa and a 41-kDa peptide. 
  Reference    Z. Naturforsch. 43c, 413—417 (1988); received February 15 1988 
  Published    1988 
  Keywords    9-kDa Phosphoprotein, Photosystem-II Particles, Photoinhibition, Protein Phosphorylation, Antibody 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0413.pdf 
 Identifier    ZNC-1988-43c-0413 
 Volume    43 
68Author    A. Hloušek-Radojčič, N. LjubešičRequires cookie*
 Title    The Development of Daffodil Chromoplasts in the Presence of Herbicides SAN 9789 and SAN 9785  
 Abstract    The effects of two pyridazinone herbicides (SAN 9789 and SAN 9785) were studied on the fine structure and carotenoid composition during the transformation of chloroplasts into chromoplasts in daffodil (Narcissus poëticus L.) flowers. SAN 9789 caused the absence of big characteristic carotene crystals and the appearance of numerous nonosmiophilic plastoglobuli in chromoplasts. The accumulation of all carotenoids was drastically reduced and the content of carotenes was 40-fold lower than in the control. SAN 9785 caused no gross abnormalities in ultrastructure of chromoplasts. The synthesis of carotenes was partially reduced to about 75%. In spite of this the accumulation of xanthophylls is two times higher than in the control. The interaction between chromoplast ultrastructure and carotenoid composition is discussed. 
  Reference    Z. Naturforsch. 43c, 418—422 (1988); received December 7 1987/January 26 1988 
  Published    1988 
  Keywords    Pyridazinone Herbicides, Chromoplast Ultrastructures, Carotenoids 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0418.pdf 
 Identifier    ZNC-1988-43c-0418 
 Volume    43 
69Author    J. Bednarz, A. Radunz, G. H. SchmidRequires cookie*
 Title    Lipid Composition of Photosystem I and II in the Tobacco Mutant Nicotiana tabacum NC 95  
 Abstract    The lipids of photosystem II particles, of chloroplasts and leaves are compared in the variegated tobacco mutant NC 95. The mutant differs from other N. tabacum mutants by the phenomenon that it has variegated leaves with green and with yellow-green leaf patches. Chloroplasts from the green leaf areas exhibit photosystem II and photosystem I reactions and have a normal lamellar system with grana and intergrana regions. Chloroplasts from the yellow-green leaf areas, how-ever, yield only photosystem I reactions and have only single stranded isolated thylakoids. Hence, this mutant offers the unique possibility to compare without the use of detergents within the same plant the lipid composition of photosystem II particles with that in intact chloroplasts, exhibiting either photosystem II and I reactions or those exhibiting exclusively photosystem I reactions. The lipids of photosystem II particles are composed of 37% glycolipids, 4% phospholipids, 5% carotenoids and 54% chlorophyll. Lipids of chloroplasts with grana stacking are composed of 75% glycolipids, 7% phospholipids, 2% carotenoids and 16% chlorophyll. Chloroplasts with single isolated thylakoids have a lipid composition consisting of 83% glycolipids, 14% phos-pholipids and only 0.5% carotenoids and 2% chlorophyll. The chloroplast lipid mixture is charac-terized in comparison to the respective leaf lipid mixture by a 16—17% higher glycolipid portion and by a 13-70% lower phospholipid content. The main difference in the lipid composition of photosystem I and II consists in the observation that chloroplasts active in only photosystem I contain more than double the amount of glycolipids and the 4-fold amount of phospholipids in comparison to photosystem II active preparations. The amount of monogalactolipid is even 3 times higher in chloroplasts active only in photosystem I when compared to those in photosystem II particles. In photosystem II particles phosphatidyl-ethanolamine is completely lacking and phosphatidylglycerol and phosphatidylinositol occur only in traces. The fatty acids of the sulfolipid are by 45% more saturated in the photosystem II particles and the digalactolipids of the photosystem II particles are by 28% more saturated than in chloroplasts exhibiting photosystem I and II activity. 
  Reference    Z. Naturforsch. 43c, 423—430 (1988); received March 3 1988 
  Published    1988 
  Keywords    Lipids, Fatty Acids, Chloroplasts, Lipid Asymmetry, Photosystem II Particles 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0423.pdf 
 Identifier    ZNC-1988-43c-0423 
 Volume    43 
70Author    JosefA. Graf, Karin Witzan, RetoJ. StrasserRequires cookie*
 Title    Cerulenin-Induced Modifications in the Fatty Acid Composition Affect Excitation Energy Transfer in Thylakoids of Petunia hybrida Leaves  
 Abstract    Dedicated to Professor Ulrich Kuli, Stuttgart, on the occasion of his 50th birthday Cerulenin, Fatty Acid Synthesis, Excitation Energy Distribution Cerulenin-induced modifications in the fatty acid composition have been used to investigate the influence of acyl lipids on excitation energy distribution in thylakoid membranes of Petunia hybrida by means of 77 K fluorescence spectroscopy. Although cerulenin has no effect on relative contents of chlorophyll and acyl lipids, changes in the fatty acid composition of all thylakoid acyl lipids have been observed. The main cerulenin effect seems to be an increase in linoleic acid at the expense of saturated and monounsaturated C16-and C18-fatty acids resulting most likely in an increase in acyl lipid species containing both linoleic and linolenic acid. Low temperature (77 K) fluorescence kinetics reveal a remarkable decrease in the ratio of the variable divided by the maximal fluorescence of photosystem II (F2(v)/F2(M>), taken as indicator for cerulenin-induced changes in this photosystem. Calculations of the excitation energy distribution terms based on a grouped bipartite model of photosynthesis suggest that a decrease in this ratio is caused by changes in energy transfer probabilities responsible for both, photochemical trapping of photosys-tem II and energetic cooperativity (grouping) between different photosystem Il-light harvesting complex-units. Moreover, changes in the conformation responsible for spillover energy transfer are most likely to occur. Correlations between cerulenin-induced modifications of fatty acid composition and energy distribution support the assumption that excitation energy transfer depends on the structural state of the lipid matrix. 
  Reference    Z. Naturforsch. 43c, 431—437 (1988); received December 29 1987/March 15 1988 
  Published    1988 
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 Identifier    ZNC-1988-43c-0431 
 Volume    43 
71Author    MatildeBarón Ayala, Gerhard SandmannRequires cookie*
 Title    The Role of Cu in Respiration of Pea Plants and Heterotrophically Growing Scenedesmus Cells  
 Abstract    In Scenedesmus about half of NADH oxidation proceeds via a cyanide-sensitive and the other half via a cyanide-insensitive respiratory pathway. In contrast, respiration is completely cyanide sensitive in pea indicating that the alternative respiratory pathway is absent. Cu deficiency in pea plants and in heterotrophically grown Scenedesmus cells interferes with respiratory activity of mitochondria. In both organisms, the cyanide-sensitive NADH oxidation was strongly decreased during cultivation in low Cu media. Cu sensitivity was also observed for the alternative respiratory pathway in Scenedesmus. These results suggest that a Cu-containing component is involved in the alternative respiratory pathway. This is the main reason why alternative respiration cannot be regarded as a compensation for low cytochrome-oxidase activities during Cu starvation. The Cu dependency of the cyanide-sensitive respiration was located at the site of cytochrome oxidase. A strong coordination of the biosynthesis of the Cu-containing cytochrome-oxidase complex was evident. When the endogenous Cu pool was low, formation of cytochrome aa 3 , another component of cytochrome oxidase, was also decreased. 
  Reference    Z. Naturforsch. 43c, 438—442 (1988); received December 7 1987/February 10 1988 
  Published    1988 
  Keywords    Cu Deficiency, Cytochrome Oxidase, Mitochondria, Pea Plants, Scenedesmus 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0438.pdf 
 Identifier    ZNC-1988-43c-0438 
 Volume    43 
72Author    Martine Bertrand, Barbara Bereza, Esther DujardinRequires cookie*
 Title    Evidence for Photoreduction of NADP + in a Suspension of Lysed Plastids from Etiolated Bean Leaves  
 Abstract    It has been investigated if photoreduction of NADP + (detected by absorption spectroscopy) may take place in lysed plastids within minutes of exposure to light. This process was made possible by removal of oxidants from the reaction mixture. Lysed plastids were suspended in a medium containing NADP + , catalase, glucose oxidase and glucose; exposure to light simultane-ously to addition of ferredoxin and ferredoxin-NADP + reductase, resulted in increased absorb-ance in the band around 340 nm, while addition of 3-phosphoglycerate resulted in the disappear-ance of this band. Ferredoxin and ferredoxin-NADP + reductase are only effective when photo-activation takes place before their addition to the medium. 
  Reference    Z. Naturforsch. 43c, 443—448 (1988); received January 25 1988 
  Published    1988 
  Keywords    NADPH, NADP + Photoreduction, Etioplasts, Absorbance Difference Spectra, Phaseolus vulgaris 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0443.pdf 
 Identifier    ZNC-1988-43c-0443 
 Volume    43 
73Author    E. Jurkiewicz, G. Hunsmann, M. Hayami, Y. Ohta, H. Schmitz, J. SchneiderRequires cookie*
 Title    Serological and Structural Comparison of Immunodeficiency Viruses from Man, African Green Monkey, Rhesus Monkey and Sooty Mangabey  
 Abstract    Human Immunodeficiency Virus, Simian Immunodeficiency Virus. Peptide Mapping We have studied the serological relationship among the human immunodeficiency virus type 1 (HIV-1), and three simian immunodeficiency viruses (SIV). SIVagm was isolated from African green monkeys (Cercopithecus aethiops), and compared with the previously described isolates of SIVmac from a rhesus macaque (Macaca mulatta) and SIVsm from a sooty mangabey (Cercocebus atys). With respect to the glycoproteins, the simian viruses represent a subgroup apparently different from HIV. To classify HIV and SIV isolates further, we compared tryptic peptide maps of the core polypeptides pl8 and p24 of HIV-2, three HIV-1 and five SIV isolates. Each peptide map was distinguishable, and differences are most prominent between the HIV-1 group and the SIVmac/SIVsm group. HIV-2 is very similar to SIVmac and SIVsm. The three SIVagm isolates form a more heterogeneous group. The p24s of all SIVagms are more similar to the p24s of HIV-1, but with respect to pl8, one isolate is similar to HIV-1, while the two others are more related to SIVmac, SIVsm, and HIV-2. 
  Reference    Z. Naturforsch. 43c, 449—454 (1988); received March 28 1988 
  Published    1988 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0449.pdf 
 Identifier    ZNC-1988-43c-0449 
 Volume    43 
74Author    Agnes-M Daub, Manfred HauserRequires cookie*
 Title    Primary Cilia in Locust Spermatocytes: Formation, Fate, and Possible Function  
 Abstract    During locust spermatocyte development, rudimentary cilia originate from all centrioles of the doubled prophasic centrosome, located in the centrosphere and specifically linked to the nuclear envelope. Membranous vesicles at the bases of the centrioles fuse to form an intracellular ampulla that contributes the ciliary membranes. Later in prophase the ampulla's membrane is integrated into the plasma membrane so that all primary cilia project into the extracellular medium and lose contact with the nucleus. As the centrioles remain ciliated on their way to their polar positions, we propose a mechanism for this migration which is based on this intimate association between centrosomes and plasma membrane, on membrane fluidity and on a contractile cell cortex. We noted a translocation of the ciliated centrioles below the cell surface at the metaphase/-anaphase transition which may be regarded as "deciliation" by light microscopy. Some possible explana-tions for the primary cilium's role in cell cycle regulation are suggested. 
  Reference    Z. Naturforsch. 43c, 455—462 (1988); received November 30 1987 
  Published    1988 
  Keywords    Primary Cilia, Pole Migration, Deciliation, Metaphase/Anaphase-Transition 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0455.pdf 
 Identifier    ZNC-1988-43c-0455 
 Volume    43 
75Author    M. Tóth, G. Szőcs, J. MolnárRequires cookie*
 Title    Field Tests with Sex Attractants of Diachrysia chrysitis and D. tutti (Lepidoptera: Noctuidae) at Several Sites in Hungary  
 Abstract    Sex attractants for the sibling taxa Diachrysia chrysitis (L.) s.str. and D. tutti (Kost.) were field tested on 9 sites in Hungary. Catches with the two already described attractant blends, Z-5-10:Ac/ Z-7-10:Ac in ratios 10:1 and 2:100, were similar to earlier results obtained in areas more to the west, chrysitis s.str. type males responding to the 10:1 while tutti type males to the 2:100 ratio. Substantial chrysitis s.str. catches were also obtained by the intermediate 1:1 blend. On all 9 sites the two taxa were co-occurring. 
  Reference    Z. Naturforsch. 43c, 463—466 (1988); received February 2 1988 
  Published    1988 
  Keywords    Sex Attractant, Field Trapping, Diachrysia chrysitis, Diachrysia tutti, Lepidoptera 
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 Identifier    ZNC-1988-43c-0463 
 Volume    43 
76Author    K. KirschfeldRequires cookie*
 Title    Navigation and Compass Orientation by Insects According to the Polarization Pattern of the Sky  
 Abstract    A recent theory attempts to explain how bees take their compass orientation from the pattern of polarized light in the sky (S. Rossel and R. Wehner, Nature 323, 128-131 (1986)). According to this theory, orientation can be erroneous and lead to the wrong course of a recruited bee in search of the foraging site whenever only a small patch of the blue sky is visible to the bee. It is shown that orientation under natural conditions is not erroneous, if the compass reference is variable in time but equally defined for both, scout bees and recruits. 
  Reference    Z. Naturforsch. 43c, 467—469 (1988); received January 25 1988 
  Published    1988 
  Keywords    Navigation, Compass Orientation, e-Vector, Insect, Bee 
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 Identifier    ZNC-1988-43c-0467 
 Volume    43 
77Author    T. Hashimoto, M. Tori, Y. Asakawa, E. WollenweberRequires cookie*
 Title    Synthesis of Two Allergenic Constituents of Propolis and Poplar Bud Excretion  
 Abstract    The prenyl ester and the phenylethyl ester of caffeic acid, formed in the bud excretion of poplar species, were shown recently to be the major contact allergens in bee-glue. An unambiguous synthesis of these compounds, based on the reaction of caffeic acid with l-bromo-3-methyl-2-butene and with ß-bromoethylbenzene, respectively, is reported. The synthetic products confirm the previously described structures of the natural products and allow further testing of their allergenic properties. 
  Reference    Z. Naturforsch. 43c, 470—472 (1988); received January 25 1988 
  Published    1988 
  Keywords    Propolis, Contact Allergens, Prenyl Caffeate, Phenylethyl Caffeate, Synthesis 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0470_n.pdf 
 Identifier    ZNC-1988-43c-0470_n 
 Volume    43 
78Author    Wolfgang Gärtner, Anette PlanggerRequires cookie*
 Title    3-Hydroxy Retinal, a New Chromophore Identified in Insect Eyes: HPLC Separation and NMR Spectroscopic Identification of the Oxime Forms  
 Abstract    3-Hydroxy retinal acts as visual chromophore instead of retinal in the eyes of several insect orders. A HPLC separa-tion system of the aldehyde and oxime isomers and their identification by 400 MHz 'H NMR spectroscopy is described. 
  Reference    Z. Naturforsch. 43c, 473—475 (1988); received February 11 1988 
  Published    1988 
  Keywords    Insect Visual Pigment, 3-Hydroxy Retinal, HPLC Separa-tion, Proton-NMR Spectroscopy 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0473_n.pdf 
 Identifier    ZNC-1988-43c-0473_n 
 Volume    43 
79Author    CarlMichael Ruyter, Helmut Schübel, Joachim StöckigtRequires cookie*
 Title    Novel Glucoalkaloids from Rauwolfia Cell Cultures — Acetylrauglucine and Related Glucosides  
 Abstract    Rauwolfia serpentina (L.) Bentham et Hook, Apocynaceae, Cell Suspension Culture, Mono-terpenoid Indole Glucoalkaloids, Acetylrauglucine From cell suspension cultures of Rauwolfia serpentina grown in an optimized production medium for the glucoalkaloid raucaffricine, a novel glucoalkaloid was isolated and identified as 17-0-acetyl-21-0-ß-D-glucopyranosyl-ajmaline (acetylrauglucine). This alkaloid is formed in very small amounts (< 5 x 10~ 4 %). The biogenetically related N"-demethylated base (acetyl-nor-rau-glucine) and the deacetyl product rauglucine have also been detected in culture extracts. In addition 21(.R)-(ß-D-glucopyranosyl)-hydroxy-sarpagan-17-al has been isolated and identified as an artifact which originates from raucaffricine. 
  Reference    Z. Naturforsch. 43c, 479—484 (1988); received March 9 1988 
  Published    1988 
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 Identifier    ZNC-1988-43c-0479 
 Volume    43 
80Author    R. G. Berger, F. DrawertRequires cookie*
 Title    Glycosilation of Terpenols and Aromatic Alcohols by Cell Suspension Cultures of Peppermint (Mentha piperita L.)  
 Abstract    Plant cell cultures effectively convert terpenoid and aromatic alcohols into glycosides. A quan-titative comparison showed a culture of peppermint (Mentha piperita) to be the most active among four species examined. The synthesis of glycosides was affected by the concentration of substrate, incubation period, cell age and aggregation, and by light. Conversion rates of exogenous alcohols were greater than 70% under optimized conditions. 
  Reference    Z. Naturforsch. 43c, 485—490 (1988); received February 26/April 27 1988 
  Published    1988 
  Keywords    Mentha piperita, Heterotrophic/Photomixotrophic Cell Cultures, Glycosides, Terpenols, Aro-matic Alcohols 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0485.pdf 
 Identifier    ZNC-1988-43c-0485 
 Volume    43 
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