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1980 (201)
161Author    N. Oel, T. K. Een, L. InghamRequires cookie*
 Title    Phytoalexins from Dolichos biflorus  
 Abstract    , 2'-hydroxygenistein, dalbergioidin, kievitone and phaseollidin have been found to accumulate in leaves and stems of Dolichos biflorus (horsegram) following inoculation with the non-pathogens Pseudomonas pisi and Phytophthora megasperma f. sp. glycinea, respectively. They are accompanied by isoferreirin (5,7,4'-trihydroxy-2'-methoxyisoflavanone), a compound not previously reported as a natural product. Coumestrol and psoralidin occur constitutively in Dolichos leaves and stems. 
  Reference    Z. Naturforsch. 35c, 923—926 (1980); received June 30 1980 
  Published    1980 
  Keywords    Leguminosae, Dolichos, Isoflavonoids, Phytoalexins, Structure Elucidation Genistein 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0923.pdf 
 Identifier    ZNC-1980-35c-0923 
 Volume    35 
162Author    Z. NaturforschRequires cookie*
 Title    Enzymatic Preparation of i4C-Labeled Phytoene, Squalene, and Geranylgeranyl Pyrophosphate from [2-nC]Mevalonic Acid  
 Abstract    1 4 C-Labeled Terpenoids, cw-Phytoene, Kaurene, Squalene, Geranylgeranyl Pyrophosphate Methods are described for an enzymatic preparation of 1 4 C-labeled terpenoids. With a cell-free system of a white mutant of Phycomyces blakesleeanus (Mucoraceae) [14C]squalene and [14C-m]phytoene can be synthesized from [2-14C]mevalonate. The application of norflurazon, a phenyl-pyridazinone herbicide, helps to increase the yield of squalene. Furthermore, the liquid endosperm of Echinocystis lobata (Cucurbitaceae) was used for the formation of either [14C(-)]kaurene from [14C]mevalonic acid or [14C-/ram']geranylgeranyl pyrophosphate in the presence of Amo 1618. The hydrocarbons formed were purified by alumina-column chromatography and preparative thm-layer chromatography (TLC). Geranylgeranyl chromatography followed by TLC. 
  Reference    Z. Naturforsch. 35c, 927—930 (1980); received August 25 1980 
  Published    1980 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0927.pdf 
 Identifier    ZNC-1980-35c-0927 
 Volume    35 
163Author    N. An, K. Ayashi, M. Azuyuki, Aeshim, Isam, N. Oguchi, H. Isashi, M. Ae, T. Akashi SakaoRequires cookie*
 Title    Distribution of Terpenes and Phenol Ethers of Asarum Species Growing in Islands in Pacific Ocean  
 Abstract    A survey of chemical compositions of ten species of Asarum subgenus Heterotropa growing in some islands in Pacific Ocean showed that two groups could be distinguished on the basis of terpene and phenyl propane compositions. 
  Reference    Z. Naturforsch. 35c, 931—935 (1980); received July 7 1980 
  Published    1980 
  Keywords    Aristolochiaceae, Asarum, Terpene, Phenyl Propane, Orcinol, Chemosystematics 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0931.pdf 
 Identifier    ZNC-1980-35c-0931 
 Volume    35 
164Author    H.-JB. Auch, E. L. EistnerRequires cookie*
 Title    Bioproduction of Axenomycins in Batch Cultures of Streptomyces lisandri  
 Abstract    The influence of various factors such as aeration, pH and size of the inoculum on production of axenomycin A, B, and D and on growth of Streptomyces lisandri was studied in batch cultures. An investigation of the nutritional requirements showed that growth and antibiotic production are not necessarily correlated. The yield of acenomycins was increased to 1.7 g per liter medium by repeated selection for a high producing strain. Bioautography showed that these strains produced a hitherto undescribed antibiotic and that all strains tested differed in the total amount of axenomycins produced but not in the composition of the fraction containing antibiotic activity. Addition to the medium of extra amounts of inorganic phosphate and various nitrogen sources showed that both nutritional components selectively inhibited axenomycin formation but did not inhibit growth of Streptomyces lisandri. Good growth of Streptomyces lisandri was observed in the presence of sucrose and its monomers (glucose, fructose), but whereas sucrose inhibited axenomycin formation almost completely, its monomers did not. 
  Reference    Z. Naturforsch. 35c, 936—944 (1980); received August 8 1980 
  Published    1980 
  Keywords    Streptomyces lisandri, Axenomycins, Bioproduction, Control by Nitrogen, Phosphate and Carbon 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0936.pdf 
 Identifier    ZNC-1980-35c-0936 
 Volume    35 
165Author    Z. NaturforschRequires cookie*
 Title    Effects of L-Methionine-S-sulfoximine on Growth and Glutathione Synthesis in Tobacco Suspension Cultures  
 Abstract    L-Methionine-S-sulfoximine, Glutathione, Tobacco, Tissue Culture Tobacco cells grown photoheterotrophically with high ammonium and sulfate concentrations are able to cope with small amounts of methionine-sulfoximine. The observed methionine-sulfoximine tolerance of tobacco suspensions is due to an extracellular glutathione and an intra­ cellular glutamine reservoir, both reservoirs are considerably reduced by treatment with methionine-sulfoximine concentrations that do not affect the growth of the cells. In tobacco suspension cultures grown with nitrate as sole nitrogen source that do not contain high amounts of glutathione and glutamine, growth inhibition by methionine-sulfoximine can be prevented by addition of these substances to the growth medium. These data indicate that synthesis of glutathione and glutamine are both inhibited by mentionine-sulfoximine; furthermore they show evidence that — in contrary to animal cells -the whole glutathione molecule is taken up by tobacco cells. Synthesis of glutathione from the consisting amino acids is inhibited by methionine-sulfoximine in crude cell homogenates to a similar extent than observed in tobacco suspensions in vivo; therefore, the activity, and not the amount of enzymes of glutathione syn­ thesis seems to be reduced by treatment with methionine-sulfoximine. As tobacco suspensions are able to recover from methionine-sulfoximine treatment with respect to accumulation of glutathione in the medium as well as with respect to growth, detoxication of methionine-sulf­ oximine has to be assumed. 
  Reference    Z. Naturforsch. 35c, 945—951 (1980); received June 6 /August 8 1980 
  Published    1980 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0945.pdf 
 Identifier    ZNC-1980-35c-0945 
 Volume    35 
166Author    L. Udw, B. Ergm AnnRequires cookie*
 Title    Adenosine Triphosphate Sulfurylase and O-Acetylserin Sulfhydrylase in Photoheterotropically and Heterotrophically Cultured Tobacco Cells  
 Abstract    Nicotiana tabacum, Cell Suspension Culture, Assimilatory Sulfate Reduction, Adenosine Tri­ phosphate Sulfurylase, O-Acetylserine Sulfhydrylase Photoheterotrophic and heterotrophic cell suspension cultures of Nicotiana tabacum have been examined for changes in specific activity of ATP-sulfurylase (EC 2.1.1 A) and OAS-sulfhydrylase (EC 4.2.99.8) during growth on different nitrogen sources. During exponential growth the specific activity of ATP-sulfurylase and OAS-sulfhydrylase remained constant and was on the same level in cells with high and with low rates of sulfate assimilation. The specific activity of both enzymes rapidly increased in green photoheterotrophic cells as well as in chloroplast-free heterotrophic cells after the sulfur from the medium had been used up. This increase was reversed when the cells were transfered back to a sulfate supplemented nutrient solution. The changes in enzyme activity due to sulfur depletion seem to indicate a regulatory mechanism for these enzymes. 
  Reference    Z. Naturforsch. 35c, 952—957 (1980); received July 4 1980 
  Published    1980 
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 Identifier    ZNC-1980-35c-0952 
 Volume    35 
167Author    W. Alter Liedgens, R. Udi, G. Rü Tzm, H. An, Sjö Rg, A.W S ChneiderRequires cookie*
 Title    Highly Efficient Purification of the Labile Plant Enzyme 5-Aminolevulinate Dehydratase (EC 4.2.1.24) by Means of Monoclonal Antibodies  
 Abstract    5-Aminolevulinate Dehydratase, Monoclonal Antibodies, Purification of 5-Aminolevulinate Dehydratase, Subunits of 5-Aminolevulinate Dehydratase, Spinach (Spinatia oleracea) 5-Aminolevulinate dehydratase (ALAD) from spinach (Spinatia oleracea) was isolated by affinity purification on an immunoabsorbens with a yield of 70 to 80% of the activity in the crude enzyme preparation. The enzyme eluted from the immunoabsorbens was pure as judged by poly­ acrylamide gel electrophoresis and is a hexamer with a subunit molecular weight of about 50000. Enzyme bound to the immunoabsorbens was able to synthesize porphobilinogen in a continuous manner. Owing to the lability of the enzyme and its low abundance in plant tissue, we have been unable to obtain similar yields of purified enzyme using classical purification procedures. This highly efficient purification was made possible by using monoclonal antibodies as described by Köhler and Milstein (Nature 256, 495 (1975)). The availability of monoclonal antibodies meant that it was not necessary to purify the enzyme to homogeneity by classical means in order to raise an antiserum specific for ALAD. Sixteen clones of cells producing anti­ bodies against ALAD were selected. They all expressed a x light chain but differed in the heavy chain class which was either y\ or y2a-The availability of pure ALAD enzyme and of highly specific antibodies against the enzyme now enables us to answer questions concerning properties, localization, intercellular transport and evolution of ALAD. It is clear that the technique used and the questions asked are not restricted to ALAD. 
  Reference    Z. Naturforsch. 35c, 958—962 (1980); received July 7 1980 
  Published    1980 
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 Identifier    ZNC-1980-35c-0958 
 Volume    35 
168Author    D. Ieter Strack, G. Erh, N. Urm An, G. Esine SachsRequires cookie*
 Title    Sinapine Esterase ü . Specificity and Change of Sinapine Esterase Activity During Germination of Raphanus sativus  
 Abstract    Raphanus, Brassicaceae, Esterase, Sinapine, Choline Esters Following a 20 to 24 h lag-phase after sowing, the onset of both rapid degradation of sinapine (sinapolycholine) and rapid increase in sinapine esterase activity in cotyledons of Raphanus sativus was observed. After 2 days of germination maximal enzyme activity was reached and declined in subsequent germination stages as rapidly as it had appeared. Esterases, active against indophenyl acetate, showed highest activity in dry seeds, declining to more than 50% between the 1st and 3rd day of germination. Starch gel electrophoresis showed that all protein extracts contained a multiplicity of esterases, active against ar-naphthyl acetate. When gels were incubated with sinapine, one new band appeared, stainable with diazotized /»-nitroaniline. This band represents sinapine esterase activity. Tests for substrate specificity towards cinnamic acid choline esters showed highest enzyme activity with sinapine. Studies on the occurrence of sinapine esterase in other Brassicaceae revealed that the enzyme activity coincides with the occurrence and degradation of sinapine. 
  Reference    Z. Naturforsch. 35c, 963—966 (1980); received September 31980 
  Published    1980 
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 Identifier    ZNC-1980-35c-0963 
 Volume    35 
169Author    A. Fleuriet, J. J. Macheix, R. Suen, R. K. IbrahimRequires cookie*
 Title    Partial Purification and Some Properties of a Hydroxycinnamoyl Glucosyltransferase from Tomato Fruits  
 Abstract    A glucosyltransferase was isolated from im mature "cherry" tom atoes and was partially purified (200-fold) by am m onium sulphate precipitation and successive chrom atography on Sephadex G-100 and DEAE-cellulose columns. The enzyme utilised the free hydroxycinnamic acids and UDP-glucose in the form ation o f their respective glucosides (pH 8.0) and glucose esters (pH 7.0); but did not accept the CoA thiolesters o f HCAs in the presence of glucose-1-phosphate. The constant glucoside/glucose ester ratio observed during purification suggests that both reactions are catalysed by the sam e enzyme. The K m values for /»-coumaric, caffeic, ferulic and sinapic acids were 0.8, 1.5, 1.4 and 2.5 hm, respectively. W ith ferulic acid as substrate, the K m value for U D PG was 10 hm. The enzyme required an -S H group for activity and the reaction was strongly inhibited by EDTA, divalent metal ions and UDP. 
  Reference    Z. Naturforsch. 35c, 967—9 (1980); received August 14 1980 
  Published    1980 
  Keywords    Glucosyltransferase, Glucosides, Glucose Esters, Hydroxycinnamic Acids, Enzyme Purification and Properties, Tom ato Fruit, Lycopersicum esculentum (Solanaceae) 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0967.pdf 
 Identifier    ZNC-1980-35c-0967 
 Volume    35 
170Author    Klaus Fuisting, Gottfried WeissenböckRequires cookie*
 Title    "Flavanone Synthase" in Oat Primary Leaves Time Course and Distribution at the Tissue and Subcellular Level  
 Abstract    Oat Primary Leaves, "Flavanone Synthase", Time Course, Localization "Flavanone Synthase" (FS) isolated from oat primary leaves shows maximal activity in the differentiating zone of five day old leaves. Activity of FS is distributed in both the upper and lower epidermis, but dominant in the mesophyll. After fractionation of mesophyll protoplasts of Avena by differential centrifugation, FS activity could only be detected in the "cytosol" and not in intact chloroplasts or other particulate fractions. 
  Reference    Z. Naturforsch. 35c, 973—9 (1980); received July 7 1980 
  Published    1980 
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 Identifier    ZNC-1980-35c-0973 
 Volume    35 
171Author    Günter DöhlerRequires cookie*
 Title    Zur photosynthetischen C 0 2-Fixierung von Synechococcus Photosynthetic C 0 2 Fixation o f Synechococcus  
 Abstract    14C 0 2 Fixation, Effect of Preillum ination and Tem perature, Synechococcus The cyanobacterium Synechococcus (Anacystis nidulans strain L 1402-1) was grown at +37 °C in 3.0 vol.% C 0 2. The effect of preillum ination with white light on the subsequent dark 14C 0 2 fixation was studied under aerobic conditions at + 3 0 ° C . The radioactive carbon first incoiporated into 3-phosphoglyceric acid was transferred during the later periods o f dark UC 0 2 fixation to phosphoenolpyruvate and aspartate. No labelling or a very low label in sugar monophosphates could be observed. D uring the d ark/light transients the initial fixation product was mainly aspartate. The pattern o f l4C -incorporation into photosynthetic products under steady state conditions (10 min photosynthesis) varied with the tem perature during the experiments. The radioactive carbon was firstly incorporated into 3-phosphoglyceric acid. D uring the later periods of photosynthetic UC 0 2 fixation an increased 14C -incorporation into aspartate and glutamate could be observed. O ur findings were interpreted with operating o f a phospho­ enolpyruvate carboxylation besides the Calvin cycle. 
  Reference    Z. Naturforsch. 35c, 978—981 (1980); eingegangen am 27. A ugust 1980 
  Published    1980 
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 Identifier    ZNC-1980-35c-0978 
 Volume    35 
172Author    NawalA. El-Rabbat, H. K. MangoldRequires cookie*
 Title    A Convenient Method for the Preparation of Pheromones from Inexpensive Starting Materials  
 Abstract    -9-Tetradecenoic acid was isolated from the total fatty acids o f beef tallow. (Z)-9-Tetra-decenol, (Z)-9-tetradecenyl acetate and (Z)-9-tetradecenal, compounds known to function as sex attractants in various insect species, were prepared from this fatty acid. 
  Reference    Z. Naturforsch. 35c, 982 (1980); received July 13 1980 
  Published    1980 
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 Identifier    ZNC-1980-35c-0982 
 Volume    35 
173Author    H. Am, E. Städler, S. Rauscher, H. R. Buser, H. Mustaparta, P. Esbjerg, H. Philipsen, O. Zethner, D. L. Struble, R. BuesRequires cookie*
 Title    Multicomponent Sex Pheromone in Agrotis segetum: Preliminary Analysis and Field Evaluation  
  Reference    Z. Naturforsch. 35c, 986—9 (1980); received July 23 1980 
  Published    1980 
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 Identifier    ZNC-1980-35c-0986 
 Volume    35 
174Author    Emst PriesnerRequires cookie*
 Title    Sex Attractant System in Polia pisi L. (Lepidoptera: Noctuidae)  
 Abstract    Electrophysiological analysis o f olfactory h air sensilla in male P. pisi has revealed four different types o f presum ed pherom one receptor cells, maximally responsive to (Z)-ll-tetradecenyl acetate (Z ll-1 4 :A c), (Z)-9-tetradecenyl acetate (Z 9-14:A c), (Z)-l 1-hexadecenyl acetate (Z ll-1 4 :A c) and (Z)-7-dodecenyl acetate (Z7-12: Ac), respectively. These four compounds were tested, singly and in various combinations, for efficacy in attracting P. pisi males in the field. High trap catches were obtained with mixtures of Z ll-1 4 :A c /Z 9 -1 4 :A c in the ratio 100/100, whereas the 100/30 and 30/100 mixtures o f the two compounds were only slightly attractive. N o male P. pisi were captured by single chemicals or binary combinations o f Z ll-1 4 :A c /Z ll-1 6 :A c , Z ll-1 4 :A c /Z 7 -1 2 :A c , Z 9 -1 4 :A c /Z l 1-16:Ac, Z 9 -1 4 :A c/Z 7 -1 2 :A c, or Z 1 1-16:A c/Z 7-12:A c. Various compounds, including Z 1 1-16:Ac and Z7-12:A c, were tried as third chemicals in ad d i­ tion to 100 ng Z 1 1-14: Ac + 100 ng Z 9-14: Ac but none increased trap catches over the basic lure. 
  Reference    Z. Naturforsch. 35c, 990—9 (1980); received August 26 1980 
  Published    1980 
  Keywords    Pheromones, Sex A ttractant, Olfactory Receptors, Alkenyl Acetates, N octuidae 
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 Identifier    ZNC-1980-35c-0990 
 Volume    35 
175Author    Martin Wenzel, Ursula LemmRequires cookie*
 Title    In vivo und in vitro Hydroxylierung von Androgenen in Ratten nach Leberschädigung und Nahrungskarenz  
 Abstract    In vivo and in vitro hydroxylation o f testosterone and dihydrotestosterone in rats after liver damage and starvation The in vivo C-2-hydroxylation o f testosterone and 5-dihydrotestosterone in rats was measured by labilisation o f tritium as H TO after injection o f [1 a, 2 a-T]testosterone or [1 a, 2a-T]5a-dihy-drotestosterone (radiospirometry). After experimental liver dam age caused by CC14 or after starvation for 60 h the hyroxylation of the androgens decreased. Sim ilar results were gained by measuring the C-2-hydroxylation of testosterone, 5 a-dihydrotestosterone and estradiol. 
  Reference    Z. Naturforsch. 35c, 995—9 (1980); eingegangen am 22. Mai 1980 
  Published    1980 
  Keywords    Hydroxylation, Steroid-Horm ones, Tritium W ater, Liver Dam age 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0995.pdf 
 Identifier    ZNC-1980-35c-0995 
 Volume    35 
176Author    Stefan Zabori, Rainer Rudolph, Rainer JaenickeRequires cookie*
 Title    Folding and Association of Triose Phosphate Isomerase from Rabbit Muscle  
 Abstract    The enzymatic activity and quaternary structure o f rabbit muscle triose phosphate isomerase remains unchanged in the concentration range from 2 ng/m l to 2 ng/m l. In this concentration range the enzyme can be reactivated after dissociation and denaturation in 6.5 m guanidine hydrochloride. Removal of the denaturant by dilution and separation o f inactive wrong aggregates (5-20%) lead back to active dimers, indistinguishable from the native enzyme as far as enzymatic and physicochemical properties are concerned. Based on the long term stability o f the enzyme, the reactivation kinetics were analyzed at low concentrations and 0 °C, conditions where the association of inactive monomers to active dim ers is predom inant in the process of reactivation. The concentration dependence of the rate of reactivation and the kinetic profiles could be described by a consecutive first-order folding and second-order association reaction scheme with the rate constants k ^ = 1.9 x 10~2 s-1 and kbi = 3 x 105 m _1 • s~\ This implies that the folded monomers o f triose phosphate isomerase, which are interm ediate states during reconstitution, cannot possess appreciable enzymatic 
  Reference    Z. Naturforsch. 35c, 999—1004 (1980); received A ugust 7 1980 
  Published    1980 
  Keywords    Association, Folding, Reconstitution, Triose Phosphate Isomerase 
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 Identifier    ZNC-1980-35c-0999 
 Volume    35 
177Author    Wilhelm Hasselbach, Andrea MigalaRequires cookie*
 Title    The Inhibition of the Calcium Transport ATPase of the Sarcoplasmic Reticulum by Fluorescamine: Evidence for an Oligomeric Functional Unit of the Calcium Transport System  
 Abstract    The labelling of the protein moiety o f the sarcoplasm ic calcium transport ATPase by fluo­ rescamine suppresses calcium transport, calcium dependent ATPase activity, protein phosphoryla­ tion by [y-32P]ATP and [32P]phosphate at different extent o f am ino group substitution. F or the hydrolysis of para nitrophenylphosphate by the calcium transport A TPase it is shown that the relationship between the extent o f amino group labelling can considerably be altered by the tem perature and the presence o f ethyleneglycol. It is shown that the am ino residues o f the phosphatidylethanolam ine moiety do not contribute to the inhibiting effect of fluorescamine labelling. The observations suggest that the different functions o f the calcium transport system are based on the cooperation o f a varying num ber o f calcium transport ATPase molecules. 
  Reference    Z. Naturforsch. 35c, 1005—1011 (1980); received A ugust 27 1980 
  Published    1980 
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 Identifier    ZNC-1980-35c-1005 
 Volume    35 
178Author    Wilhelm Hasselbach, Vera KoenigRequires cookie*
 Title    Low Affinity Calcium Binding Sites of the Calcium Transport ATPase of Sarcoplasmic Reticulum Membranes  
 Abstract    Calcium binding sites having low affinity constants of < 103 M-1 were titrated in native sarcoplasmic reticulum vesicles as well as in lipid deprived m em branes and in the isolated calcium transport ATPase. Short time calcium binding m easurem ents and the determ ination o f the calcium binding heat allow to distinguish low affinity calcium binding sites located on the external surface of the sarcoplasmic reticulum m em branes from those present in the section o f the transport molecule directed to the vesicular space. The same num ber o f internal binding sites was found for preparations deprived of their lipid content as well as of preparations depleted o f their lipids and of their accessorial proteins. Magnesium interferes with calcium binding to the external as well as to the internal low affinity calcium binding sites. The im plications o f the existence o f the low affinity calcium binding sites in the internal section o f the calcium transport ATPase are discussed. 
  Reference    Z. Naturforsch. 35c, 1012 (1980); received A ugust 27 1980 
  Published    1980 
  Keywords    Sarcoplasmic Reticulum, Calcium Binding, Low Affinity Binding Sites 
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 Identifier    ZNC-1980-35c-1012 
 Volume    35 
179Author    Volker EhrhardtRequires cookie*
 Title    Modulation of Amino Acid Transport in Rat Liver Slices by Tissue Preincubation  
 Abstract    In rat liver slices, a prolonged preincubation resulted in a stim ulation of AIB and alanine uptake. The increase of transport o f both amino acids can be ascribed to a reduction o f K t without an alteration o f Vt . The enhancem ent o f transport seems to be restricted to the A m ediation as indicated by the findings that only the N a +-dependent, M eAIB-inhibitable portion of AIB transport was increased by the prolonged preincubation, and, furtherm ore, that the uptake of cysteine, a specific substrate for system ASC in liver cells, was not affected. The effect o f an extended preincubation on AIB transport was abolished by the addition o f high concentrations o f AIB and alanine to the preincubation medium. Several other am ino acids tested did not affect the increase o f AIB transport. The observed stim ulation of transport seems not to be due to the derepression o f the synthesis of transport proteins, as cycloheximide and 5-azacytidine did not block the increase o f AIB uptake. The enhancem ent of am ino acid transport does not appear to be a result o f a release from transinhibition since the uptake of alanine was markedly enhanced after 3 h o f preincubation while the alanine concentrations in the incubated liver slices did not change significantly. 
  Reference    Z. Naturforsch. 35c, 1019—1023 (1980); received January 15/August 141980 
  Published    1980 
  Keywords    Adaptive Regulation, A m ino Acid Transport, Liver Slices, Preincubation, R at 
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 Identifier    ZNC-1980-35c-1019 
 Volume    35 
180Author    Alfons RadunzRequires cookie*
 Title    Binding of Antibodies onto the Thylakoid Membrane. VI. Asymmetric Distribution of Lipids and Proteins in the Thylakoid Membrane  
 Abstract    Dedicated to Professor W. Menke at the Occasion o f His 70th Birthday Chloroplasts, Lipids, Proteins, A ntibody Binding, Thylakoid M em brane Surface The maximal binding o f antibodies out o f monospecific antisera to proteins and lipids onto three different chloroplast preparations is compared. In these preparations different parts o f the thylakoid m em brane surface are accessible to antibodies. Whereas stroma-freed chloroplasts bind antibodies only at the outer surface, also the inner m em brane surface is exposed in the two chloroplast preparations which were obtained by ultrasonication and subsequent fractionating centrifugation. In the ultrasonic sedim ent the inner surface is prevailing. In the ultrasonic supernatant antibodies do not only react with the inner and outer surface but also w ith con­ siderable parties of the interior o f the thylakoid mem brane. It was found that the thylakoid m em brane surface exposed to the strom a consists preponder­ antly of proteins whereas the surface directed towards the interior o f the thylakoids consists mainly of lipids. All proteins involved in electron transport such as ferredoxin, ferredoxin-N A D P+-reductase, plastocyanin, cytochrome f and the coupling factor o f photophosphorylation are detectable in the outer surface. The molecules o f the coupling factor span the thylakoid membrane from the outside to the inside. They hinder the binding o f antibodies to mono-galactosyl diglyceride and to a polypeptide with the apparent molecular weight 24000. The polypeptide 24000 is a m ajor com ponent o f the m em brane proteins, and is detected on the outer and inner surface of the m em brane. The m ajor part of this polypeptide, however, is located in the interior of the thylakoid membrane. The lipid mixture has a different com position in the outer surface than on the inside face of the membrane. The sulfoquinovosyl diglyceride and the phosphatides, phosphatidyl glycerol, phosphatidyl cholin and phosphatidyl inositol are stronger concentrated in the outer surface than in the inside face. The neutral monogalactosyl diglyceride and di-or trigalactosyl diglyceride, however, occur in the inner surface in higher concentrations than in the outer surface. The major part of the sulfoquinovosyl diglyceride and o f the monogalactosyl diglyceride are located in the interior of the membrane. 
  Reference    Z. Naturforsch. 35c, 1024—1031 (1980); received A ugust 131980 
  Published    1980 
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 Identifier    ZNC-1980-35c-1024 
 Volume    35 
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