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1979 (244)
61Author    Sabine Milz, Horst RimplerRequires cookie*
 Title    Verbreitung von Iridoiden in der Gattung Verbena und einigen anderen Verbenoideae Iridoids in Verbena and Some Other Verbenoideae  
 Abstract    12 species of the genus Verbena and one Citharexylum species have been examined for iridoids. Besides the known compounds verbenaline, hastatoside, griselinoside, lamiide, ipolamiide and brasoside, two new iridoids, pulchelloside I (1) [2] and pulchelloside II (2) [3] have been isolated from Verbena species. The structures and absolute configurations of pulchelloside I and II have been determined by spectroscopical methods and some chemical reactions. Citharexylum solanaceum has been shown to contain lamiide and durantoside I. The distribution of the iridoids is in excel­ lent agreement with the taxonomic treatment of the genus Verbena by Schauer. The taxonomic significance of our data and some data from the literature regarding the classification of the sub­ family Verbenoideae is discussed. 
  Reference    Z. Naturforsch. 34c, 319 (1979); eingegangen am 20. Februar 1979 
  Published    1979 
  Keywords    Iridoids, Verbena, Citharexylum, Chemotaxonomy, Pulchelloside 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0319.pdf 
 Identifier    ZNC-1979-34c-0319 
 Volume    34 
62Author    Ruth Seeger, Tjakko StijveRequires cookie*
 Title    Amanitin Content and Toxicity of Amanita verna Bull  
 Abstract    The < x-, /?-, and ^-amanitin content of 11 samples of Amanita verna Bull., collected during 1975 — 1978 in Germany and Switzerland, has been determined by high performance thin-layer chromatography (HPTLC) of crude methanolic extracts. The toxicity (i. v. LD50 for mice of defatted, lyophilized, methanolic extracts) of 3 samples has been compared with that of A. phal­ loides from the same site of collection. The amanitin content of A. verna ranged from 2250 to 4570 mg/kg dry weight; the fungi con­ tained almost as much ß-as a-amanitin, whereas the y-amanitin content amounted to about 12% of the total amanitin. A. verna contained less amanitin (65% on the average) than A. phalloides from the same collection site, but it was not significantly less toxic, since the phallotoxins contributed to the toxicity of either species in our tests. 
  Reference    Z. Naturforsch. 34c, 330 (1979); received February 5 1979 
  Published    1979 
  Keywords    Amanitins, Amanita verna, Amanita phalloides, Mushroom Poisoning, Chromatography 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0330.pdf 
 Identifier    ZNC-1979-34c-0330 
 Volume    34 
63Author    Brigitte Kopp, Wolfgang Löffelhardt, Wolfgang KubelkaRequires cookie*
 Title    Untersuchungen zum Biosyntheseort und Transport von Cardenoliden in Convallaria majalis L. Cardenolide Biogenesis and Translocation in Convallaria majalis L  
 Abstract    Convallaria majalis L., [4-14C] Progesterone, Cardenolide Biogenesis, Translocation [4-14C] Progesterone, fed to leaves and whole plants of Convallaria majalis L., was incorporated into the main cardenolide glycosides. After application of [4-14C] progesterone to the leaves of intact plants via the epidermis labelled desglucocheirotoxin, convallatoxin and convallatoxol were isolated from rhizomes and roots. When the precursor was administered to rhizome cuttings no radioactivity could be detected in the cardiac glycoside fraction. The experiments pointed out that during the stage of flowering biosynthesis of cardenolide glycosides takes place in the leaves of Convallaria majalis rather than in the subterranean parts of the plant. A translocation of these substances from the leaves to rhizomes and roots seems possible. 
  Reference    Z. Naturforsch. 34c, 334 (1979); eingegangen am 5. Februar 1979 
  Published    1979 
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 Identifier    ZNC-1979-34c-0334 
 Volume    34 
64Author    Wolfgang Miiller, Gerhard Nohynek, Friedhelm Korte, Frederic CoulstonRequires cookie*
 Title    Aufnahme, Verteilung, Umwandlung und Ausscheidung von Dieldrin in nicht-menschlichen Primaten und anderen Labortieren Absorption, Body Distribution, Metabolism, and Excretion of Dieldrin in Non-Human Primates and Other Laboratory Animals  
 Abstract    Dieldrin in Mammals, Comparative Pharmacokinetics, Comparative Biotransformation Using 14C-labelled dieldrin, the resorption, body distribution, and rate of excretion as well as the metabolism was investigated qualitatively and quantitatively. The experiments with mice, rats, rabbits, Rhesus monkeys, and chimpanzees were performed under identical conditions to obtain reliably comparable results. 
  Reference    Z. Naturforsch. 34c, 340 (1979); eingegangen am 10. Januar 1979 
  Published    1979 
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 Identifier    ZNC-1979-34c-0340 
 Volume    34 
65Author    BryanP. Cooper, HansG. TrüperRequires cookie*
 Title    Improved Synthesis and Rapid Isolation of Millimole Quantities of Adenylylsulfate  
 Abstract    An improved enzymatic method for the synthesis of adenylylsulfate (APS) from adenosine 5'-phosphate using APS-reductase from Thiobacillus denitrificans is described. Isolation of millimole quantitities of this sulfur nucleotide is achieved rapidly by means of ion exchange chromatography on a strongly basic ion exchange resin. A facile and reproducible desalting procedure is described. 
  Reference    Z. Naturforsch. 34c, 346 (1979); received March 2 1979 
  Published    1979 
  Keywords    Thiobacillus denitrificans, Sulfur Metabolism, Adenylylsulfate Synthesis, Adenylylsulfate Isolation, APS-Reductase 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0346.pdf 
 Identifier    ZNC-1979-34c-0346 
 Volume    34 
66Author    Frank Seela, Johann Ott, Helmut RosemeyerRequires cookie*
 Title    Immobilisierung von Adenosinacetalen mit variablem Alkylidenrest — die Funktion des Spacers bei enzymatischer Desaminierung Immobilization of Adenosine-Acetals with Variable Alkylidene Residues — the Function of the Spacer during Enzymatic Deamination —  
 Abstract    Acetalation of the cis-diol moiety of adenosine or inosine with aliphatic ketoesters of different chain lengths leads to alkylidene derivatives of the nucleosides, which differ in the number of methylene groups in the hydrocarbon chain. By alkaline hydrolysis of the ester group in l a — c or 3 a —c the corresponding acids 2 a —c and 4 a —c have been prepared. The configuration of the new chiral centres has been determined as R. Enzymatic deamination of the alkylidene derivatives of adenosine leads to the inosine compounds. The rate of deamination reaction is raised by an increasing number of methylene groups in the alkylidene residues or by use of the esters instead of the acids. The alkylidene derivatives of adenosine were coupled with 6-aminohexylagarose yielding polymers with adenosine as ligands. No enzymatic deamination of the polymer with the shortest spacer was observed. The polymers with the longer spacers were converted to the corresponding inosine derivatives. The velocity of the deamination reaction was raised by an increasing spacer length. 
  Reference    Z. Naturforsch. 34c, 350—358 (1979); eingegangen am 30. 12. 1978/12. 2. 1979 
  Published    1979 
  Keywords    Cyclic 0-2', 3'-Adenosine-acetals, Affinity Resins, Spacer, Adenosine Deaminase 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0350.pdf 
 Identifier    ZNC-1979-34c-0350 
 Volume    34 
67Author    Lech Dudycz, Ryszard Stolarski, Reynaldo Pless, David ShugarRequires cookie*
 Title    A 1H NM R Study of the Syn-Anti Dynamic Equilibrium in Adenine Nucleosides and Nucleotides with the Aid of Some Synthetic Model Analogues with Fixed Conformations  
 Abstract    The syn-anti equilibrium about the glycosidic bond in adenosine and some related analogues was studied by means of *H NMR spectroscopy, with the aid of several model analogues fixed in given conformations either by intramolecular bonding, or by introduction of a bulky substituent. A model unambiguously and exclusively in the syn conformation is 8-(a-hydroxyisopropyl) adenosine; while one fixed in the a n ti conformation is 8,5'-anhydro-8-oxoadenosine. A new analogue, fixed in the high an ti conformation, is 8,2'-0-isopropylidenearabinofuranosyladenine. Several additional new model compounds were synthesized and their properties are described. With the aid of these models, the syn-anti dynamic equilibrium was examined for adenosine and some related compounds in different solvent systems, and the conformer populations evaluated quantitatively. The validity of the procedure applied, and the accuracy of the results, are critically examined, and compared with findings obtained by other procedures. Available literature data on the syn-anti equilibrium in other 8-substituted adenosines are re analyzed in the light of the present results. An analysis is also presented of the interdependence of the various conformational parameters, i. e. conformation about the glycosidic bond and those of the sugar ring and exocyclic carbinol group, in adenosine and 2',3'-0-isopropylideneadenosine. 
  Reference    Z. Naturforsch. 34c, 359 (1979); received November 21 1978 
  Published    1979 
  Keywords    NMR Spectroscopy, Conformation, S yn -A n ti Equilibrium, Purine Nucleosides and Nucleotides, Chemical Syntheses 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0359.pdf 
 Identifier    ZNC-1979-34c-0359 
 Volume    34 
68Author    E. Lengfelder, E. F. ElstnerRequires cookie*
 Title    Cyanide Insensitive Iron Superoxide Dismutase in Euglena gracilis Comparison of the Reliabilities of Different Test Systems for Superoxide Dismutases  
 Abstract    Two proteins (Px and P2 , with mol weights of 57,500 and 27,500, respectively) were isolated from Euglena gracilis. Both proteins show cyanide-insensitive superoxide dismutase activity in the "classical" superoxide dismutase assay, using xanthine-xanthine oxidase as 0 2 ~ generator. If 0 2'~ is generated chemically (autoxidation of reduced anthraquinone), photochemically (illuminated riboflavine) or pulse radiolytically, only protein Pt but not P2 shows SOD activity. Protein P t contains l g atom (determined: 0.82) iron (no Mn or Cu) per mole protein and may thus be defined as iron-superoxide dismutase. Protein P2 , showing the spectral properties of a flavoprotein, exhibits the activities of ferredoxin-NADP-oxidoreductase and "diaphorase". The cyanide-insensi-tive SOD-activity of this "diaphorase" in the xanthine oxidase-assay for superoxide dismutase makes this classical and commonly used test unreliable for assaying cyanide insensitive SOD activities. The existence of the "prokaryote-type" of superoxide dismutase (Fe-SOD) in Euglena gracilis is exceptional for an eukaryotic, autotrophically grown organisms. 
  Reference    Z. Naturforsch. 34c, 374 (1979); received February 9 1979 
  Published    1979 
  Keywords    Fe-Superoxide Dismutase, Superoxide Dismutase Test Systems, E uglena gracilis, Pulse Radiolysis 
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 Identifier    ZNC-1979-34c-0374 
 Volume    34 
69Author    H.-G Löffler, K.-H RohmRequires cookie*
 Title    Comparative Studies on the Dodecameric and Hexameric Forms of Yeast Aminopeptidase I  
 Abstract    Yeast Aminopeptidase I, Molecular Forms, Immunological Behaviour Yeast aminopeptidase I, when purified from autolysates of brewer's yeast, is obtained in two molecular forms a) the enzymatically active dodecameric complex (Mr = 640 000, S 2 0 ,w = 22 S) and b) inactive hexamers (Mr = 320 000, S 2 0 ,w = 12 S). Although the amino acid composition of the 12 S protein is very similar to that of the active enzyme, the hexamers behave differently in ionic ex­ change chromatography and during electrophoresis on polyacrylamide gels. Moreover, the anti­ genic properties of 12 S and 22 S aminopeptidase forms suggest a considerable degree of structural diversity. Several strains of Saccharom yces cerevisiae did not contain hexameric forms although their 22 S aminopeptidase was immunologically indistinguishable from brewer's yeast amino­ peptidase. It is proposed that the hexameric protein aminopeptidase subunits. 
  Reference    Z. Naturforsch. 34c, 381 (1979); received February 20 1979 
  Published    1979 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0381.pdf 
 Identifier    ZNC-1979-34c-0381 
 Volume    34 
70Author    SatishK. Sharma, JinnieM. Garrett, StewartA. BrownRequires cookie*
 Title    Separation of the S-Adenosylmethionine: 5-and 8-Hydroxyfuranocoumarin O-Methyltransferases of Ruta graveolens L. by General Ligand Affinity Chromatography  
 Abstract    Two S-adenosyl-L-methionine:furanocoumarin O-methyltransferases of R . graveolens, acting at the 5-and 8-hydroxyls of the psoralen nucleus, were completely resolved by adsorption on a general affinity ligand, 5 -(3-carboxypropanamido) xanthotoxin, followed by specific desorption by bergaptol and xanthotoxol, respectively. The 5-O-methyltransferase was purified 450-fold by this procedure, the 8-O-methyltransferase 112-fold, and both enzyme fractions were electrophoretically homogeneous. No resolution could be achieved of the activity against two 5-hydroxypsoralens or of the activity against two 8-hydroxypsoralens, and conclusive evidence is presented for the existence of only one 5-O-methyltransferase and only one 8-O-methyltransferase acting on linear furanocoumarins. In tro d u c tio n 
  Reference    Z. Naturforsch. 34c, 387 (1979); received March 9 1979 
  Published    1979 
  Keywords    Coumarins, Furanocoumarins, O-Methyltransferases, Affinity Chromatography, R u ta graveolens 
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 Identifier    ZNC-1979-34c-0387 
 Volume    34 
71Author    F. M. Veronese, 0. Schiavon, R. Bevilacqua, G. RodighieroRequires cookie*
 Title    Drug-Protein Interaction: 8-Methoxy Psoralen as Photosensitizer of Enzymes and Amino Acids  
  Reference    Z. Naturforsch. 34c, 392 (1979); received August 3 1978 
  Published    1979 
  Keywords    8-Methoxy-psoralen, Furocoumarins, Photochemotherapy, Photosensitization of Amino Acids and Proteins, Drug-Protein Interaction 
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 Identifier    ZNC-1979-34c-0392 
 Volume    34 
72Author    M. G. Ganesan, M. Lakshmanan, K. V. Ravindran, C. D. Am OdaranRequires cookie*
 Title    Action of Citrinin on Liposomes  
 Abstract    Citrinin, Ion leakage, Liposomes Citrinin, a mycotoxin, was studied for its effect on artificial membranes (liposomes). Of the three (net positive, negative and neutral) liposomal preparations tested, the membrane carrying a net positive charge was preferentially acted upon by citrinin and in this case even the lowest con­ centration was found to be sufficient for causing a high degree of damage. This is the first report of evidence that citrinin has a direct effect on membranes. It was shown to exhibit concentration dependency in its lytic activity on artificial membranes 
  Reference    Z. Naturforsch. 34c, 397 (1979); received December 1 1978/January 29 1979 
  Published    1979 
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 Identifier    ZNC-1979-34c-0397 
 Volume    34 
73Author    H. J. Schmidt, M. Sommer, J. PichotkaRequires cookie*
 Title    Effect of Mechanical Traumatization on Rate and Constancy of Oxygen Uptake of Isolated Diaphragms  
 Abstract    Diaphragms of mice were traumatized by division parallel or transversally to the muscle fibres. The extent of traumatization was varied by the degree of subdivision. Oxygen uptake was measured by the Warburg technique. Undivided diaphragms as control displayed constant oxygen uptake for the four hours of observation. With divided diaphragms oxygen uptake was unstable. Division parallel to the muscle fibres resulted in continuous decrease of oxygen uptake after a normal initial phase; the decline was significantly steeper with increasing extent of traumatization. Divi­ sion transversally to the muscle fibres resulted in an initial increase of oxygen uptake followed in a second phase by a continuous decrease. The initial increase as well as the final decrease of oxygen uptake was more pronounced with higher extent of subdivision. In tro d u c tio n 
  Reference    Z. Naturforsch. 34c, 400 (1979); received June 27 1978/February 7 1979 
  Published    1979 
  Keywords    Isolated Tissues, Oxygen Consumption, Mechanical Traumatization, Division of Tissue Samples 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0400.pdf 
 Identifier    ZNC-1979-34c-0400 
 Volume    34 
74Author    J. Luisetti, H. Möhwald, H. J. GallaRequires cookie*
 Title    Spectroscopic and Thermodynamic Studies of Chlorophyll Containing Monolayers and Vesicles Part II: Chlorophyll a and Pheophytin a Aggregation on DMPC Vesicles  
 Abstract    Absorption and fluorescence experiments on pheophytin and chlorophyll containing lipid bilayer vesicles are reported. Pheophytin aggregates on the vesicles are established from an additional red shifted band (at 695 nm) in the absorption spectrum. These aggregates contain pheophytin in an arrangement with the molecular planes of the porphyrin rings being parallel and cover about 10% of the vesicle surface. The lipid phase dissolves pheophytin up to a molar ratio of 15% above the lipid phase transition. This solubility limit decreases hardly on solidification of the lipid. For chlorophyll a containing vesicles the aggregates are not observed in the absorption spectrum. The chlorophyll solubility is about equal to that of pheophytin. This suggests that the phase separa­ tion indicated from fluorescence measurements at temperatures below the lipid phase transition does not lead to the formation of strongly bound chlorophyll aggregates. In tro d u c tio n 
  Reference    Z. Naturforsch. 34c, 406—413 (1979); received January 25 1979 
  Published    1979 
  Keywords    Lipid Bilayers, Chlorophyll, Phase Separation, Absorption Spectroscopy, Fluorescence Spectroscopy 
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 Identifier    ZNC-1979-34c-0406 
 Volume    34 
75Author    GeorgH. Schmid, Pierre ThibaultRequires cookie*
 Title    Evidence for a Rapid Oxygen-Uptake in Tobacco Chloroplasts  
 Abstract    A fast oxygen uptake, induced by a sequence of short (5 /usee) saturating flashes was observed in chloroplasts of wild type tobacco and two chlorophyll-deficient tobacco mutants. One of the chlorophyll mutants is the earlier described variegated tobacco NC 95. Chloroplasts of this mutant exhibit only photosystem I mediated photoreactions, hence the observed oxygen uptake is to be associated with photosystem I. This is further substantiated by the fact that the oxygen uptake is insensitive to DCMU in the two chloroplast types used, which have both photosystems fully func­ tioning. The uptake depends on the addition of electron acceptors like p-benzoquinone in intact chloroplasts or on p-benzoquinone or ferricyanide in chloroplasts that have lost the envelope. In dark adapted chloroplasts, therefore, under these conditions the overall apparent gas exchange in the first two flashes is consumption. Although the uptake is slower than photosynthetic oxygen evolution it clearly affects the oxygen yield in the flash sequences. This is demonstrated by several experiments in which the apparent oxygen consumption in the absence of DCMU oscillates with a periodicity of four. We have indications that in chloroplasts of the tobacco aurea mutant Su/su the oxygen uptake is faster than in wild type chloroplasts. 
  Reference    Z. Naturforsch. 34c, 414 (1979); received February 14 1979 
  Published    1979 
  Keywords    Chloroplasts, Oxygen uptake, Oscillations, Photosynthesis 
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 Identifier    ZNC-1979-34c-0414 
 Volume    34 
76Author    S. Reimer, K. Link, A. TrebstRequires cookie*
 Title    Comparison of the Inhibition of Photosynthetic Reactions in Chloroplasts by Dibromothymoquinone, Bromonitrothymol and Ioxynil  
 Abstract    The inhibition of photosynthetic electron flow in broken chloroplasts by dibromothymoquinone and dibromothymohydroquinone (DBMIBH2) is reversed by dithiothreitol (DTT) as well as by serum albumin. The reversal of DBMIBH2 inhibition by DTT shows a time lag, that of DBMIB only, when chloroplasts and DBMIB had been preilluminated. This is to show that chloroplasts reduce DBMIB and that probably DBMIBH2 is the actual inhibitor species. Bromonitrothymol, ioxynil and related inhibitory phenolic compounds have a different relation­ ship of inhibitory potency to chemical structure than DCMU and the analogous triazinone herbicide metribuzin but nevertheless inhibit photosynthetic electron flow at the same functional site. This is supported by the finding that labelled metribuzin is displaced from the thylakoid membrane by bromonitrothymol and ioxynil indicating identical binding sites. On the other hand inhibition by the phenolic inhibitors bromonitrothymol and ioxynil but not that of DCMU and metribuzin has a time lag of about 4 min. 
  Reference    Z. Naturforsch. 34c, 419 (1979); received October 31 1978 
  Published    1979 
  Keywords    Photosynthesis, Inhibition, Herbicides, Dibromo-thymoquinone, Bromonitrothymol, Ioxynil 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0419.pdf 
 Identifier    ZNC-1979-34c-0419 
 Volume    34 
77Author    Ursula Lehmann-Kirk, GeorgH. Schmid, Alfons RadunzRequires cookie*
 Title    The Effect of Antibodies to Violaxanthin on Photosynthetic Electron Transport  
 Abstract    Chloroplasts, Photosystem II, Thylakoid M em brane, Violaxanthin, Antibody An antiserum to violaxanthin in h ibits photosynthetic electron transport between water, iodide or tetram ethylbenzidine and various electron acceptors in chloroplasts from green tobacco (N icotian a tabacum var. John W illiam 's B ro a d lea f). However, electron transport from m anganese or diphenyl-carbazide to these acceptors is not im paired. The typical photosystem I reaction from D P IP / ascorbate to anthraquinone-2-sulfonate in the presence of DCMU shows no inhibition. From this it is concluded that the effect of violaxanthin on the photosynthetic electron transport chain lies on the oxygen-evolving sid e of photosystem II before the site from which diphenylcarbazide or m anganese donate electrons. In the presence of DCM U after preillum ination we find an effect of the antiserum on fluo­ rescence. The reaction of the antibodies to violaxanthin with stroma-freed chloroplasts depends on the condition of the thylakoid m embrane. Chloroplasts which are still sw ellable react in a bivalent manner and are agglutinated. Non sw ellable chloroplasts react only in a m onovalent manner. This specific binding was dem onstrated by m eans of the Coombs-test. From these reactions it follow s that the antigenic determ inants of violaxanthin are accessible to the antibodies, hence, they must be located in the outer surface of the thylakoid membrane. 
  Reference    Z. Naturforsch. 34c, 427 (1979); received February 5 1979 
  Published    1979 
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 Identifier    ZNC-1979-34c-0427 
 Volume    34 
78Author    Klaus Großmann, Ursula Seitz, HannsUlrich SeitzRequires cookie*
 Title    Transcription and Release of RNA in Isolated Nuclei from Parsley Cells  
 Abstract    Isolated Nuclei, in vitro Transcription, Plant Suspension Cultures An in vitro transcription system using nuclei from freely suspended callus cells of Petroselinum crispum is described. The use of a filtration technique allowed the measurement of transcription and release of RNA simultaneously over very short time intervals. The transcription showed a biphasic time course, with an early maximum at 2 and a later one at 20 minutes. The early maximum was ascribed to the activity of polymerase II (a-amanitin sensitive), the later to that of polymerase I. While the transcriptional process was independent of the temperature used for incubation up to 26 °C and even increased with temperatures above that, the release of RNA transcribed was in­ hibited by temperatures above 36 °C. 
  Reference    Z. Naturforsch. 34c, 431 (1979); received February 20 1979 
  Published    1979 
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 Identifier    ZNC-1979-34c-0431 
 Volume    34 
79Author    ThomasL J Boehm, Dusan DrahovskyRequires cookie*
 Title    Die Sequenzkomplexität transkribierter unique D N A Sequenzen im Genom von Maus P815 Mastocytoma Zellen Sequence Complexity of Transcribed Unique DNA Sequences in Genome of Mouse P815 Mastocytoma Cells  
 Abstract    The sequence complexity of nuclear RNA from mouse liver, mouse spleen and highly malignant P815 mastocytoma was measured by nRNA driven hybridization to unique DNA sequences of P815 cells. The unique DNA sequences represent 63% of the total nuclear DNA of P815 cells and their availibility in hybridization experiments was found to be 76%. Of these sequences 7.8% formed hybrids with nuclear RNA of this cell, about 11.5% with mouse spleen and about 14.53> with mouse liver nuclear RNA. Assuming an asymmetrical transcription, the complexities of these transcripts are 2.8 X 1 0 8 nucleotides for mouse P815 mastocytoma, 4.3 X 108 for mouse spleen and about 5.3 X 108 nucleotides for mouse liver. Cellular specifity of the transcribed information was analyzed in additivity experiments, in which unique DNA sequences, not complementary to the nuclear RNA of one cell were annealed to the nuclear RNAs of the two other tissues/cells. In these experiments most of the nuclear RNA se­ quences of P815 cells were found to be also present in the nucleus of mouse liver and spleen. Only a small portion of the unique DNA sequences of P815 mastocytoma (about 1.2% correspond­ ing to 4.4 X 107 nucleotides) was found to be complementary only to P815 mastocytoma nuclear RNA. 
  Reference    Z. Naturforsch. 34c, 436 (1979); eingegangen am 28. Dezember 1978/13. Februar 1979 
  Published    1979 
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 Identifier    ZNC-1979-34c-0436 
 Volume    34 
80Author    Paul Miller, W. Alfried, A. Linden, Claudio NicoliniRequires cookie*
 Title    Physico-Chemical Studies of Isolated Chromatin Compared with in situ Chromatin after Partial Hepatectomy in the Rat  
 Abstract    Chromatin was isolated from rat liver cells at 0, 3, 5, 11, 18 and 24 h following partial hepa­ tectomy. Consistent with findings in cultured cells stimulated to proliferate, there was an increase in chromatin molar ellipticity measured at 276 nm, and a decrease in thermal stability 3 to 8 h after surgery. These events occured prior to the onset of DNA synthesis. These early changes be­ tween non-proliferating (G0) and proliferating (Gj) cells, as well as later chromatin conformational changes observed at S and G2 phases, mimic changes in template activity. Results with sheared and unsheared chromatin (both with in vitro and in vivo systems) prove that structural and functional changes can be caused by even the slightest shearing during chromatin preparation, suggesting the loss of native chromatin organization. To eliminate this problem, ex­ periments were also conducted using chromatin in situ. A flow cytometer (FCM) was used to study unfixed liver cell suspensions stained with ethidium bromide (EB). Fluorescence was mea­ sured in the green spectral range after addition of increasing amounts of EB. Experimental evidence is provided that the same alteration in chromatin conformation can be best detected using low molar ratios of EB per unit DNA due to greater fluorescence emission in Gj respect to G0 cells. These correlated studies demonstrate that the same changes controlling chromatin organization in situ are detected also in the tertiary-quaternary structure of "isolated" chromatin. These changes in chromatin conformation are macromolecular events related to cell proliferation both at the G0 —Gt and Gt —S transitions. 
  Reference    Z. Naturforsch. 34c, 442 (1979); received December 15 1978/February 19 1979 
  Published    1979 
  Keywords    Isolated Chromatin, Partial Hepatectomy, Molar Ellipticity, Thermal Stability, Flow Cytometry 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0442.pdf 
 Identifier    ZNC-1979-34c-0442 
 Volume    34 
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