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1988[X]
101Author    K. KirschfeldRequires cookie*
 Title    The Role of Dorsal Rim Ommatidia in the Bee's Eye  
 Abstract    Bee, Astronavigation. e-Vector Analysis A recent model of celestial e-vector analysis by the bee assumes that polarization information is transformed into modulation of perceived brightness while the bee scans the sky by rotating its field of view. It is shown that the sug-gested simple strategy to read compass information from the polarization pattern of the sky in natural conditions can work only in a part of the sky close to the zenith. The bee would need a different strategy for other regions of the sky. 
  Reference    Z. Naturforsch. 43c, 621—623 (1988); received April 131988 
  Published    1988 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0621_n.pdf 
 Identifier    ZNC-1988-43c-0621_n 
 Volume    43 
102Author    Denis Barron, RagaiK. IbrahimRequires cookie*
 Title    Synthesis of Flavonoid Sulfates. II. The Use of Aryl Sulfatase in the Synthesis of Flavonol-3-sulfates  
 Abstract    The rates of aryl sulfatase hydrolysis of several 7-, 4'-and 3-sulfated flavonoids were compared and found to follow the order 7 or 4' >» 3. The complete resistance of the 3-sulfate ester to enzyme hydrolysis provided a unique and convenient method for the synthesis of a number of naturally occurring flavonol-3-sulfates from the corresponding higher sulfated analogs in quanti-tative yield. 
  Reference    Z. Naturforsch. 43c, 625—630 (1988); received February 23/May 17 1988 
  Published    1988 
  Keywords    Flavonol Sulfate Esters, Synthesis, 13 C NMR, FAB-MS, UV Spectra 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0625.pdf 
 Identifier    ZNC-1988-43c-0625 
 Volume    43 
103Author    Denis Barron, RagaiK. IbrahimRequires cookie*
 Title    Synthesis of Flavonoid Sulfates. III. Synthesis of 3',4'-ortho Disulfates Using Sulfur Trioxide-trimethylamine Complex, and of 3'-SuIfates Using Aryl Sulfatase  
 Abstract    A number of flavonoid 3',4'-disulfates were synthesized from the corresponding 4'-sulfate esters, using sulfur trioxide-trimethylamine complex. Desulfation of the sulfate esters using aryl sulfatase demonstrated that the rate of hydrolysis of the 3'-sulfate group was slower than either the 7-or 4' groups, thus allowing the specific synthesis of flavonol 3,3'-disulfates. The effects of ori/io-disulfation on the L1 C NMR spectra of flavonoids, and the regative FAB-MS spectra of di-and trisulfated flavonoids are discussed. 
  Reference    Z. Naturforsch. 43c, 631—635 (1988); received March 18 1988 
  Published    1988 
  Keywords    Flavonoid Sulfate Esters, Synthesis, 13 C NMR, FAB-MS, UV Spectra 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0631.pdf 
 Identifier    ZNC-1988-43c-0631 
 Volume    43 
104Author    AndreasB. Wolff, Maung Thynn, Elisabeth Gorge, Dietrich WernerRequires cookie*
 Title    Wyerol and Wyerone Accumulation in Tissue Cultures of Vicia faba  
 Abstract    Callus cultures of various cultivars of Vicia faba were studied for regeneration. During callus growth on agar or in liquid medium a black tissue was often observed correlated with an autolysis of some cells. With those tissues callus growth and regeneration of plants was inhibited. In black callus the phytoalexin synthesis is induced without infection by microorganism. The main phyto-alexins in the callus tissue are wyerol and wyerone, with some wyeronic acid and dihydrowyerone. Wyerol was found especially in the cultivar Troy at a high concentration. In four cultivars the pooled phytoalexin concentration varied between 10 and 150 pg-g _1 fresh weight. 
  Reference    Z. Naturforsch. 43c, 636—640 (1988); received March 7/May 30 1988 
  Published    1988 
  Keywords    Vicia faba, Callus and Liquid Cultures, Regeneration, Phytoalexins 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0636.pdf 
 Identifier    ZNC-1988-43c-0636 
 Volume    43 
105Author    P. A. Bäumker, S. Arendt, R. WiermannRequires cookie*
 Title    Metabolism of Ferulic Acid Sucrose Esters in Anthers of Tulipa cv. Apeldoorn: I. The Accumulation of Esters and Free Sugars  
 Abstract    The authors of Tulipa cv. Apeldoorn accumulate a large amount of ferulic acid sucrose esters. In addition to the well-known diferuloyl-(DFS) and triferuloyl sucrose esters (TFS), a new phenylpropanoid characterized as a monoester of ferulic acid and sucrose is described. Like TFS and DFS, this ester exhibits an accumulation maximum in the early stages of pollen development. Numerous free sugars have been extracted from Tulipa anthers. Three of them were identified as sucrose, glucose and fructose. Sucrose as the main component is accumulated in extremely high amounts during specific developmental stages (= 20% of the dry weight). After separation of the anthers into an anther wall fraction (AWF) and pollentapetum (PTF), each fraction shows a different accumulation kinetic of the free sugars and the ferulic acid esters. A correlation could be observed between the occurrence of the esters and sucrose in the pollen-tapetum fraction during the anther development. 
  Reference    Z. Naturforsch. 43c, 641—646 (1988); received May 16 1988 
  Published    1988 
  Keywords    Tulipa cv Apeldoorn, Anthers, Ferulic Sucrose Esters, Free Sugars 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0641.pdf 
 Identifier    ZNC-1988-43c-0641 
 Volume    43 
106Author    P. A. Bäumker, S. Arendt, R. WiermannRequires cookie*
 Title    Metabolism of Ferulic Acid Sucrose Esters in Anthers of Tulipa cv. Apeldoorn: II. Highly Specific Degradation of the Esters by Different Esterase Activities  
 Abstract    Protein extracts from anthers of Tulipa cv. Apeldoorn catalyze the degradation of ferulic acid sucrose esters. Different products are generated when triferuloyl sucrose (TFS) and diferuloyl sucrose (DFS) were applied as substrates. By the aid of reversed-phase HPLC, TLC and spectro-scopy the products could be identified as free ferulic acid, monoferuloyl sucrose ester [feruloyl-sucrose(mono)] and two different diesters of ferulic acid and sucrose [feruloylsucrose(di) and the endogenously occurring diferuloylsucrose (DFS)]. By means of protein fractionation (chromatofocusing, anion exchange HPLC and molecular sieving HPLC), four different enzyme activities involved in the degradation process could be separated. According to their catalytic properties, they were characterized as esterases (= EA). The partially purified esterase activity I (EA I) obtained after fractionation by chromatofocus-ing catalyzes the formation of feruloylsucrose(di) and ferulic acid when TFS is used as substrate. Incubations with EA la or EA lb isolated in smaller portions lead to the same product pattern. The esterase activity II (EA II) degrades TFS to ferulic acid and DFS. DFS as substrate is only accepted by the EA I activities, in all three cases ferulic acid and feruloyl sucrose(mono) are formed as products. The kinds of different degradation reactions clearly indicate that one enzyme (= the EA II activity) catalyzes exclusively the formation of DFS from TFS. Both enzymes, EA I and EA II, exhibit a high specificity towards ferulic acid sucrose esters. Hydroxycinnamic sucrose esters with only sinapic acid moieties do not function as substrates. When enzymatically formed sucrose esters like feruloylsucrose(di), feruloylsucrose(mono) and mono-sinapoylsucrose were used as substrates, no product formation could be observed. Applying SFS as substrate, only the ferulic acid moiety was released by EA I. Further, naturally occurring esters (glucose-and CoA-esters of p-coumaric, caffeic, ferulic and sinapic acid; chlorogenic acid; BGM) tested so far were not degraded by EA I and EA II. It is assumed that these esterase activities play a specific role in the ferulic acid metabolism in Tulipa anthers. 
  Reference    Z. Naturforsch. 43c, 647—655 (1988); received May 16 1988 
  Published    1988 
  Keywords    Tulipa cv Apeldoorn, Anthers, Ferulic Acid Sucrose Esters, Degradation, Esterases 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0647.pdf 
 Identifier    ZNC-1988-43c-0647 
 Volume    43 
107Author    Frank Beise, Harald Labischinski, Hans BradaczekRequires cookie*
 Title    On the Relationships between Molecular Conformation, Affinity towards Penicillin-Binding Proteins, and Biological Activity of Penicillin G-Sulfoxide  
 Abstract    The binding capacity of penicillin G-sulfoxide towards the penicillin-binding proteins (PBP) of Staphylococcus aureus H was studied. The sulfoxide and its parent compound, penicillin G, differ only in two aspects, the sulfur-bound oxygen and an altered conformation of the five-membered thiazolidine-ring system. These minor alterations of the penicillin structure resulted in a drastical decrease of binding activity (about two orders of magnitude) of the sulfoxide derivative towards its target enzymes. Furthermore, the sulfoxide did not exhibit the selectivity of subinhibitory doses for PBP 3, as could be observed for penicillin G. The biological consequences of this behaviour were monitored via growth curves, uptake of cell wall label, and analysis of the cell wall. Binding studies revealed that comparable growth inhibi-tion and impairment of cell wall label uptake were achieved by at least a 100-fold higher penicillin G-sulfoxide concentration, compared to its parent compound. In cell wall analysis, the application of high doses of the antibiotics, i.e. nearly saturated PBP, verified the above mentioned observation. Surprisingly, small but significant differences in cell wall composition occurred using subinhibitory doses, probably due to the altered affinity towards PBP 3, supporting the hypothesis of an important role of this PBP in peptidoglycan transpeptida-tion. 
  Reference    Z. Naturforsch. 43c, 656—664 (1988); received March 25/June 28 1988 
  Published    1988 
  Keywords    Penicillin G, Penicillin G-Sulfoxide, Penicillin-Binding Proteins, Biological Activity, Structure Activity Relationships 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0656.pdf 
 Identifier    ZNC-1988-43c-0656 
 Volume    43 
108Author    MarilenaE. Lekka, DemokritosC. Tsoukatos, AlexandrasD. Tselepis, VassiliosM. KapoulasRequires cookie*
 Title    Semisynthetic Preparation of l-0-hexadecyl-2-acetyl-sn-glyceryl-3- phosphorylcholine (Platelet Activating Factor)  
 Abstract    -2-acetyl-sn-glyceryl-3-phosphorylcholine (platelet activating factor, PAF), (1.9 pmol) was prepared from the total lipid extract of the protozoan Tetrahymena pyriformis 9xlO 7 cells. The procedure involved mild alkaline hydrolysis of the total lipids, followed by acetylation and purification of the product by preparative TLC and HPLC. The yield was 60% with respect to the content of l-0-alkyl-2-acyl-sn-glyceryl-3-phosphorylcholine in the total lipids, determined after preparative TLC. The alkyl side chain of the semisynthetic PAF was composed of hexadecyl residue. Our product was identified as PAF according to its biological activity, the chromatographic behaviour on TLC and HPLC, the physicochemical properties and the be-haviour under treatment with PLA2 and Lipase from Rhizopus arrhizus. The above procedure is proposed as a facile, inexpensive and convenient method. 
  Reference    Z. Naturforsch. 43c, 665—670 (1988); received March 7 1988 
  Published    1988 
  Keywords    Platelet Activating Factor, Tetrahymena pyriformis, Ether Lipids, Platelets, Phospholipids l-0-hexadecyl 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0665.pdf 
 Identifier    ZNC-1988-43c-0665 
 Volume    43 
109Author    Thomas Vom Bruch, Klaus-Heinrich RöhmRequires cookie*
 Title    Fluorescence Properties of Hog Kidney Aminoacylase I  
 Abstract    The state of the tryptophan residues of porcine kidney aminoacylase I (EC 3.5.1.14) was investigated by fluorescence spectroscopy and chemical modification. The pH-dependence of the fluorescence emission spectrum of the enzyme indicates that its native conformation prevails between pH 6 and 9.5. Within this range, the ionization of a residue with an apparent pKa of 7.1 quenches the enzyme fluorescence by about 15%. A similar reduction of fluorescence intensity accompanies the inactivation of aminoacylase I by treatment with N-bromosuccinimide in low excess. This suggests that in both cases a single tryptophyl residue out of eight residues per subunit is affected. Quenching by iodide revealed that, in the native conformation of the enzyme, 5—6 tryptophans per subunit are accessible, while 2—3 are buried within the protein. 8-Anilinonaph-thalene-L-sulfonate (ANS) is tightly bound to aminoacylase I (1 mol/mol dimer, K d < 1 PM). ANS binding does not interfere with substrate turnover; the spectroscopic properties of the amino-acylase-ANS complex are consistent with bound ANS being excited by radiationless energy transfer (RET) from buried tryptophyl residues of the enzyme. 
  Reference    Z. Naturforsch. 43c, 671—678 (1988); received June 3 1988 
  Published    1988 
  Keywords    Aminoacylase, Kidney, Tryptophan, Fluorescence, ANS 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0671.pdf 
 Identifier    ZNC-1988-43c-0671 
 Volume    43 
110Author    Manfred Schwenk, Erwin ZochRequires cookie*
 Title    Purification and Characterization of Calcium-Activated Neutral Proteinase from Calf Thymus  
 Abstract    A calcium-activated neutral proteinase (CANP) was prepared from the soluble fraction of calf thymus and purified to electrophoretical homogeneity. The purified proteinase was shown to consist of two subunits, each of 80 kDa, in contrast to rabbit skeletal muscle calpain which was shown to consist of 80 kDa and 30 kDa subunits. The calcium requirement for 50% activation was 0.55 mM, indicating that this enzyme belongs to the low calcium sensitive type of CANP, named mCANP or Calpain II. Optimal conditions of enzyme activity towards 0.8% casein as substrate are pH 7.5, a calcium concentration of 1.5 mM, the presence of an SH-reducing agent and an incubation temperature of 30 °C. The enzyme is inhibited by Zn :+ , p-chloromercuribenzoate and N-ethylmaleimide. 
  Reference    Z. Naturforsch. 43c, 679—685 (1988); received June 27/July 12 1988 
  Published    1988 
  Keywords    Calpain II, Proteinase, Ca 2+ -Activated, Thymus (calf) 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0679.pdf 
 Identifier    ZNC-1988-43c-0679 
 Volume    43 
111Author    Ulrich Schreiber, Christof Klughammer, Christian NeubauerRequires cookie*
 Title    Measuring P700 Absorbance Changes around 830 nm with a New Type of Pulse Modulation System  
 Abstract    A new measuring system for monitoring absorbance changes around 830 nm is described, which was developed by modification of a commercially available pulse modulation fluorometer. All modifications concern the emitter-detector unit of the fluorometer, such that only this unit needs to be exchanged when changing from fluorescence to absorbance measurements and vice versa. The new system is shown to be well-suited for measuring redox changes of P700, the reaction center of photosystem I, in intact leaves and isolated chloroplasts. The observed kinetic changes at 830 nm in response to single turnover or multiple turnover saturating flashes are practically identical to those previously measured around 700 nm. The signal/noise ratio is sufficiently high to give well-resolved kinetics without signal averaging. When P700 is oxidized by far-red back-ground light, valuable information on the state of the intersystem electron transport chain is given by the re-reduction kinetics induced by single or multiple turnover saturating flashes. Such meas-urements are facilitated by the use of poly-furcated fiberoptics. With intact leaves, almost identi-cal responses are found when measuring through the leaf (transmission mode) or from the leaf surface (remission mode). Modulated chlorophyll fluorescence can be measured in parallel; appli-cation of saturation pulses for fluorescence quenching analysis produces transient P700 oxidation without oversaturating the measuring system. The information on the P700 redox state comple-ments that obtained from fluorescence measurements, yielding a new practical tool in plant physiological research. 
  Reference    Z. Naturforsch. 43c, 686—698 (1988); received May 9 1988 
  Published    1988 
  Keywords    P700, Chlorophyll Fluorescence, Pulse Modulation, Photosynthesis 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0686.pdf 
 Identifier    ZNC-1988-43c-0686 
 Volume    43 
112Author    Gerhard Sandmann, Peter BögerRequires cookie*
 Title    Accumulation of Protoporphyrin IX in the Presence of Peroxidizing Herbicides  
 Abstract    Peroxidizing herbicides were assayed for their capacity to accumulate tetrapyrrole-like com-pounds in the liquid culture medium when growing the xanthophycean alga Bumilleriopsis filifor-mis. We have isolated and purified this compound by HPLC. For identification optical, fluores-cence, NMR and mass spectroscopy were employed. All these techniques showed that the accu-mulation product is protoporphyrin IX. This tetrapyrrole was found, although to a different extent, using either chlorophthalim, oxadiazon, oxyfluorfen or LS 82-556. Accumulation of proto-porphyrin IX caused by peroxidizing compounds was also found in light-grown Bumilleriopsis cells and heterotrophically (dark-)grown Scenedesmus cells, but neither in light-grown Scenedes-mus cells nor in dark-grown Neurospora. 
  Reference    Z. Naturforsch. 43c, 699—704 (1988); received August 10 1988 
  Published    1988 
  Keywords    Bumilleriopsis, FAB Mass Spectrometry, HPLC, NMR Spectrometry, Chlorophthalim, Neuro-spora 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0699.pdf 
 Identifier    ZNC-1988-43c-0699 
 Volume    43 
113Author    Walter Oettmeier, Klaus Masson, Andreas DonnerRequires cookie*
 Title    QSAR of Nitro-diphenylethers as Inhibitors of Cyclic Photophosphorylation  
 Abstract    A number of 25 nitro-diphenylethers have been synthesized and assayed for their inhibitory activity in N-methylphenazonium-methosulfate mediated cyclic photophosphorylation. Their p/50-values were in the range from 3.5 to 5.3. A QSAR-analysis revealed that the lipophilicity of the nitro-diphenylethers as expressed by Z:t played a major role. In addition, the Taft steric parameter £s in positions 6', 4' and 2' (in decreasing order) contributed to the inhibitory activity. For maximal biological activity, positions 4' and 6' should be left unsubstituted whereas a bulky substituent is required for position 2'. 
  Reference    Z. Naturforsch. 43c, 705—708 (1988); received May 31 1988 
  Published    1988 
  Keywords    Cyclic Photophosphorylation, Herbicides, Nitro-diphenylethers, Quantitative Structure-Activity Relationship 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0705.pdf 
 Identifier    ZNC-1988-43c-0705 
 Volume    43 
114Author    Y. Shiraiwa, K. P. Bader, G. H. SchmidRequires cookie*
 Title    Mass Spectrometry Analysis of Oxygen Gas Exchange in High-and LOW-C0 2 Cells of Chlorella vulgaris  
 Abstract    Oxygen gas exchange was monitored in the unicellular green alga Chlorella vulgaris 211 — 11 h by means of a mass spectrometer equipped with a special membrane gas-inlet-system and a photosynthetic reaction vessel. C02-dependent I8 02-uptake as well as ,6 02-evolution were ana-lyzed in both High-and Low-C02 cells. In High-C02 cells, the 18 Oruptake in the light (UL) decreased by 65% upon addition of 3 mM NaHC03, while l6 02-evolution (E) was increased approx. 1.8 times by the same treatment. 18 02-uptake in the dark (UD) was not affected by the addition of external inorganic carbon (Ci). The addition of 3.3 mM NaHCO, also affected UL and E in Low C02-cells, however, to a minor extent. UL under C02-saturating conditions was light intensity-independent up to 2 klux and 1.2 klux in High-and Low-C02 cells, respectively. Above these light intensities UL increased approx. 4-fold in High-and approx. 6-fold in Low-C02 cells. Under C02-limiting conditions, however, UL increased in High-CO: cells even under very low light intensities, showing that photorespiratory oxygen uptake occurred even in the near vicinity of the light compensation point. Under C02-saturating and strong light conditions UL represented almost half of E in Low-C02 cells and about 30% of E in High-C02 cells. In Low-C02 cells addition of ethoxyzolamide (EZA), an inhibitor of carbonic anhydrase, enhanced UL and suppressed E and NET under C02-limiting conditions, whereas the compound had only a minor effect on High-C02 cells. DCMU (3 |XM) strongly inhibited E and UL under C02-saturating conditions, with the remain-ing UL being smaller than UD. KCN (1 mM) and SHAM (1.5 mM) added to DCMU-treated Low-C02 cells suppressed UL by approx. 50%. The resulting value corresponded to half of UD. KCN also inhibited E under CÓ2-saturating conditions, with UL being strongly enhanced showing a maximal uptake at 0.4 mM KCN. Under these conditions NET was nearly zero. The effect seems to be due to an inhibition of RubisCO and an enhancement of Mehler reactions. At 0.7 mM KCN, DCMU entirely inhibited UL, but oxygen uptake appeared increased after turning the light off. This uptake corresponded to approx. 60% of UD. Whereas KCN and SHAM inhibited approx. 70% of UD, only 16% of UL was suppressed. These results suggest that the contribution of mitochondrial respiration to UL was négligeable, since UL seemed to be suppressed in the light under C02-saturated conditions. Iodoacetamide, which is an inhibitor of the Calvin cycle and thereby diverts carbon into the respiratory pathway, inhibited E and NET under C02-saturating conditions, but did not affect UL. This result also shows that UL is not due to mitochondrial respiration. A hydroxylamine derivative [20, 21] which changes the ratio of the RuBP carboxyla-tion to oxygenation activity in tobacco leaves did not affect this ratio in Chlorella. 
  Reference    Z. Naturforsch. 43c, 709—716 (1988); received May 24 1988 
  Published    1988 
  Keywords    Chlorella, Oxygen Gas Exchange, Carbonic Anhydrase, Mass Spectrometry 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0709.pdf 
 Identifier    ZNC-1988-43c-0709 
 Volume    43 
115Author    C. Nespoulous, P. Fabisch, A. Radunz, G. H. SchmidRequires cookie*
 Title    Immunological Study on the Structural Difference between Ribulose- 1,5-bisphosphate Carboxylase/Oxygenase from Nicotiana tabacum var. John William's Broadleaf and the Tobacco Mutant Su/su  
 Abstract    RuBP Carboxylase/Oxygenase, Antibodies, Oxygenase Activity, Ratio RuBP Carboxylase/ Oxygenase-Antibodies, Tobacco mutant Su/su In the present paper we have attempted to characterize by means of immunological methods the molecular difference between ribulose 1,5-bisphosphate carboxylase/oxygenase from the wild type TV. tabacum var. John William's Broadleaf and the tobacco mutant Su/su. The tobacco mutant Su/su exhibits in comparison to the wild type a higher photorespiratory activity. The reagents used in the present study are monospecific antisera to the two bifunctional enzymes to be compared. We have analyzed the oxygenase activity of the two enzymes in dépendance on the binding of the amount of antibodies out of the homologous and the not homologous antiserum. These analyses have shown, that the enzymes of both phenotypes were 40% stronger inhibited in the equivalence regions with respect to their oxygenase function by antibodies of the antiserum to ribulose 1,5-bisphosphate carboxylase/oxygenase of the mutant than by antibodies of the wild type antiserum. It should be noted that the antiserum to the mutant enzyme exhibits a 25% lower antibody titer, than the antiserum to the wild type enzyme. In the region of extreme antibody excess, i.e. when antibodies are mostly monovalently bound and most antigenic determinants are saturated with antibodies, the oxygenase activity of both enzymes decreases towards zero in the presence of the homologous as well as in the presence of non-homologous antibodies. In the region of excess of antigenic determinants, that is when only a few antibody molecules can bind onto the enzymes, only the oxygenase activity of the mutant enzyme is inhibited by its homologous antibodies by 40%. This apparent difference in the molecu-lar structure of the two bifunctional enzymes to be compared is neither caught in the double immuno diffussion test nor in the tandem crossed immuno electrophoresis, using the two antisera as test reagents. In all cases only fused precipitation bands are observed. Chemical modification of ribulose 1,5-bisphosphate carboxylase/oxygenase by hydroxylamine treatment or treatment with o-(/?-nitrophenyl)hydroxylamine or simple heating of the enzyme to 50 °C are immunologically characterized. As a consequence of such treatment considerably less antibodies are adsorbed. The strongest influence exerts a treatment with o-(p-nitrophenyl)-hydroxylamine with simultaneous heat treatment of the enzyme for 20 min at 50 °C. 
  Reference    Z. Naturforsch. 43c, 717—726 (1988); received July 4 1988 
  Published    1988 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0717.pdf 
 Identifier    ZNC-1988-43c-0717 
 Volume    43 
116Author    SeymourSteven BrodyRequires cookie*
 Title    Rebinding of the 33 kDalton Polypeptide of Photosystem II to the D-l/D-2 Sub-Core Complex  
 Abstract    Specific and stoichiometric binding is shown between the D-l/D-2 sub-core complex and the 33 kDa polypeptide of photosystem II. Fluorescence from chlorophyll is used as an endogenous probe. When binding occurs there is an increase in fluorescence yield, as well as changes in both the fluorescence spectrum and excitation spectrum. 
  Reference    Z. Naturforsch. 43c, 727—730 (1988); received January 28/May 31 1988 
  Published    1988 
  Keywords    Photosynthesis, Reaction Center, Photosystem II, Chlorophyll, Fluorescence 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0727.pdf 
 Identifier    ZNC-1988-43c-0727 
 Volume    43 
117Author    B. V. Burger, P. J. Pretorius, Jonine Stander, G. R. GriersonRequires cookie*
 Title    Mammalian Pheromone Studies, VII*. Identification of Thiazole Derivatives in the Preorbital Gland Secretions of the Grey Duiker, Sylvicapra grimmia, and the Red Duiker, Cephalophus natalensis  
 Abstract    Mammalian Pheromones, Semiochemicals, Mass Spectrometry, 13 C and 'H NMR. Thiazole Derivatives 2-Isobutyl-l ,3-thiazole and its 4,5-dihydro derivative were identified in the preorbital gland secretions of the grey duiker, Sylvicapra grimmia, and the red duiker, Cephalophus natalensis, but are absent from the preorbital secretion of the blue duiker, C. monticola. These two compounds which are present in high, but varying concentrations in the secretions of male grey duikers, are present in low concentrations in the secretions of females. This seems to be the only consistent significant difference between the secretions of male and female grey duikers and together with the fact that only males mark out their territories, was construed as evidence in favour of these two compounds playing a significant role in the territorial behaviour of male grey duikers. 
  Reference    Z. Naturforsch. 43c, 731—736 (1988); received March 28 1988 
  Published    1988 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0731.pdf 
 Identifier    ZNC-1988-43c-0731 
 Volume    43 
118Author    M. Wink, D. Schneider, L. WitteRequires cookie*
 Title    Biosynthesis of Pyrrolidine Alkaloid-Derived Pheromones in the Arctiid Moth, Creatonotos transiens: Stereochemical Conversion of Heliotrine  
 Abstract    In larvae and later developmental stages of Creatonotos transiens, which had been reared on the pyrrolizidine alkaloid 75-heliotrine, a new major metabolite was detected by capillary GLC. The structure of this metabolite was determined by GLC-MS (EI, CI-MS) and l3 C NMR to be 1R-heliotrine and 7/?-heliotrine-N-oxide. 7/?-Heliotrine is likely to be the direct precursor for the pheromone R(—)-hydroxydanaidal. 
  Reference    Z. Naturforsch. 43c, 737—741 (1988); received May 4/June 13 1988 
  Published    1988 
  Keywords    Creatonotos, Pyrrolizidine Alkaloids, Heliotrine, Male Pheromone, Hydroxydanaidal 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0737.pdf 
 Identifier    ZNC-1988-43c-0737 
 Volume    43 
119Author    M. Suwalsky, L. Gimenez, V. Saenger, F. NeiraRequires cookie*
 Title    X-Ray Studies on Phospholipid Bilayers. VIII. Interactions with Chlorpromazine * HCl  
 Abstract    Chlorpromazine is a widely used phenothiazine tranquilizer known to alter the shape of normal erythrocytes and their osmotic fragility. In order to understand the nature of the interactions chlorpromazine • HCl (CPZ HCl) was made to interact with phospholipid bilayers formed by dimyristoylphosphatidylethanolamine (DMPE) and dimyristoylphosphatidylcholine (DMPC). This study was carried out by X-ray diffraction on crystalline powders of various molar mixtures of CPZ -HCl with DMPE and DMPC, with and without water. It was found that CPZ -HCl significa-tively affects the bilayer structure of DMPC in the presence of water, but not that of DMPE. 
  Reference    Z. Naturforsch. 43c, 742—748 (1988); received March 23/June 13 1988 
  Published    1988 
  Keywords    X-Ray Diffraction, Phospholipid, Bilayer, Chlorpromazine @BULLET HCl 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0742.pdf 
 Identifier    ZNC-1988-43c-0742 
 Volume    43 
120Author    Horst Pitterich, Rüdiger LawaczeckRequires cookie*
 Title    Effect of Preparative Procedures on Ghostcells from Bovine Erythrocytes  
 Abstract    Several methods for the preparation of "white ghosts" or "resealed ghosts" were described in the recent literature. This article compares three methods to prepare white, resealed ghosts from bovine erythrocytes based on the principle of hypotonic lysis. The methods described differ by the removal of hemoglobin from the empty cells. The main difference between the standard centrifu-gation, the gelfiltration and the hollow-fibre diafiltration is the mechanical stress on the leaky membranes after swelling in hypotonic media. Mean cellular volumes, rates of potassium-efflux and the access of impermeable dyes to cytoplasmatic proteins are criteria to differentiate between ghostcell-populations. 
  Reference    Z. Naturforsch. 43c, 749—753 (1988); received March 18 1988 
  Published    1988 
  Keywords    Red Blood Cells, Erythrocyte Ghosts, Gelfiltration, Diafiltration 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0749.pdf 
 Identifier    ZNC-1988-43c-0749 
 Volume    43 
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