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41Author    Andre Bellossi, Chantal Rocher, Michel RuellouxRequires cookie*
 Title    Effect of a Pulsed Magnetic Field and of First Cold-Pressure Sunflower Oil on Mice  
 Abstract    In previous studies it has been shown that exposure of mice to a 12-Hz 6 mT unipolar square pulsed magnetic field (PM F) suppressed the excess of weight due to application of 1st cold-pressure sunflower oil. This time we considered the effect of oil and/or PMF on the growing curves lifespans of mice. The exposure took place for 30 min 5 days a week, from the 7th week of life to death. The results are 1) a broken slope in the growing curves from the 125th day of aging: the exposed mice were lighter than the controls, keeping the differ­ ences between the growing curves needed a repeated exposure all life long; 2) a significant increase in the lifespan of the controls which received oil versus the controls which received water; 3) an increase in the lifespan of the exposed mice versus the non-exposed control batches. On one hand it has been reported that essential polyunsaturated fatty acids found in first cold-pressure sunflower oil played a prominent role in membrane structures and in immune equilibrium. On the other hand, it was activate N a+,K+-ATPase. 
  Reference    Z. Naturforsch. 55c, 267 (2000); received September 20 1999 
  Published    2000 
  Keywords    Magnetics Fields, Mice, Sunflower Oil 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0267.pdf 
 Identifier    ZNC-2000-55c-0267 
 Volume    55 
42Author    Stylianos Tsakiris3, Panagoula Angelogianni3, KleopatraH. Schulpisb, Panagiotis Behrakis3Requires cookie*
 Title    Protective Effect of L-Cysteine and Glutathione on Rat Brain Na+,K+-ATPase Inhibition Induced by Free Radicals  
 Abstract    The aim of this study was to investigate whether the preincubation of brain homogenates with L-phenylalanine (Phe), L-cysteine (Cys) or reduced glutathione (G SH) could reverse the free radical effects on N a+,K+-ATPase activity. Two well established systems were used for the production of free radicals: 1) F e S 0 4 (84 ^i m) plus ascorbic acid (400 |o.m) and 2) F e S 0 4, ascorbic acid and H20 2 (1 mM) for 10 min at 37 °C in hom ogenates o f adult rat whole brain. Changes in brain N a+,K+-ATPase activity and total antioxidant status (TAS) were studied in the presence of each system separately, with or without Phe, Cys or GSH. TAS value reflects the amount of free radicals and the capacity of the antioxidant enzymes to limit the free radicals in the homogenate. N a+,K+-ATPase was inhibited by 35 -5 0 % and TAS value was decreased by 5 0 -6 0 % by both systems of free radical production. The enzy­ matic inhibition was completely reversed and TAS value increased by 150-180% when brain homogenates were preincubated with 0.83 mM Cys or GSH. However, this N a+,K+-ATPase inhibition was not affected by 1.80 m M Phe, which produced a 4 5 -5 0 % increase in TAS value. It is suggested that the antioxidant action of Cys and GSH may be due to the binding of free radicals to sulfhydryl groups of the m olecule, so that free radicals cannot induce N a+,K+-ATPase inhibition. Moreover, Cys and GSH could regulate towards normal values the neural excitability and metabolic energy production, which may be disturbed by free radical action on N a+,K+-ATPase. 
  Reference    Z. Naturforsch. 55c, 271—2 (2000); received October 8/Decem ber 21 1999 
  Published    2000 
  Keywords    L-Cysteine, Reduced Glutathione, L-Phenylalanine, Free Radicals, N a+, K+-ATPase 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0271.pdf 
 Identifier    ZNC-2000-55c-0271 
 Volume    55 
43Author    Melánia Babincová3, Veronika Altanerová, Miloš Lampertc, Čestmír Altanerb, Eva Machová, Miron Šrámkac, Peter Babinec3, Uniba SkRequires cookie*
 Title    Site-Specific in vivo Targeting of Magnetoliposomes Using Externally Applied Magnetic Field Fax: + (4 2 1 )-7 -6 5 4 -2 5 -8 8 2 . E-mail: babincova@fmph  
 Abstract    M agnetoliposom es, Drug Targeting, Kidney Cancer Human serum albumin labeled with technetium-99m was encapsulated together with mag­ netite particles into phosphatidylcholine/cholesterol liposomes. In order to investigate the stability of this complex and its ability to be used for magnetic drug targeting, the in-vivo distribution after intravenous administration in rats was estimated. For in-vivo targeting an SmCo permanent magnet with intensity -0 .3 5 T was attached near the right kidney. Differ­ ence between the relative radioactivity in the magnetically targeted right kidney (25.92±5.84%) and non-targeted left kidney (0.93±0.05%) is sufficiently high for relevant clinical applications. 
  Reference    Z. Naturforsch. 55c, 278—281 (2000); received October 20/November 22 1999 
  Published    2000 
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 Identifier    ZNC-2000-55c-0278 
 Volume    55 
44Author    Christoph Bauer3, Thomas Burger3, Martin Stetterb, ElmarW. Lang3Requires cookie*
 Title    A Neural Network Model for the Self-Organization of Cortical Grating Cells  
 Abstract    A neural network model with incremental Hebbian learning of afferent and lateral synap­ tic couplings is proposed,which simulates the activity-dependent self-organization o f grating cells in upper layers of striate cortex. These cells, found in areas VI and V2 of the visual cortex of monkeys, respond vigorously and exclusively to bar gratings of a preferred orienta­ tion and periodicity. R esponse behavior to varying contrast and to an increasing number of bars in the grating show threshold and saturation effects. Their location with respect to the underlying orientation map and their nonlinear response behavior are investigated. The number of emerging grating cells is controlled in the model by the range and strength of the lateral coupling structure. 
  Reference    Z. Naturforsch. 55c, 282 (2000); received July 5/Decem ber 10 1999 
  Published    2000 
  Keywords    Self-Organization, Nonlinearities, Visual Cortex, (Anti-)H ebbian Learning, Lateral Plasticity 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0282.pdf 
 Identifier    ZNC-2000-55c-0282 
 Volume    55 
45Author    HartmutK. Lichtenthaler, Johannes Zeidler, Jörg Schwender, Christian MüllerRequires cookie*
 Title    The Non-Mevalonate Isoprenoid Biosynthesis of Plants as a Test System for New Herbicides and Drugs against Pathogenic Bacteria and the Malaria Parasite  
 Abstract    1-Deoxy-D-xylulose 5-Phosphate Pathway, Fosmidomycin, Isopentenyl diphosphate, Isoprene, 2-C-Methyl-D-erythritol 4-phosphate Higher plants and several photosynthetic algae contain the plastidic 1-deoxy-D-xylulose 5-phosphate / 2-C-methyl-D-erythritol 4-phosphate pathway (DOXP/MEP pathway) for iso­ prenoid biosynthesis. The first four enzymes and their genes are known of this novel pathway. All of the ca. 10 enzymes of this isoprenoid pathway are potential targets for new classes of herbicides. Since the DOXP/MEP pathway also occurs in several pathogenic bacteria, such as Mycobacterium tuberculosis, and in the malaria parasite Plasmodium falciparum, all inhibi­ tors and potential herbicides of the DOXP/MEP pathway in plants are also potential drugs against pathogenic bacteria and the malaria parasite. Plants with their easily to handle DOXP/MEP-pathway are thus very suitable test-systems also for new drugs against patho­ genic bacteria and the malaria parasite as no particular security measures are required. In fact, the antibiotic herbicide fosmidomycin specifically inhibited not only the D O X P reduc-toisomerase in plants, but also that in bacteria and in the parasite P. falciparum, and cures malaria-infected mice. This is the first successful application of a herbicide of the novel isoprenoid pathway as a possible drug against malaria. Invited Trends A rtic le 
  Reference    Z. Naturforsch. 55c, 305 (2000); received February 22/March 2 2000 
  Published    2000 
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 Identifier    ZNC-2000-55c-0305 
 Volume    55 
46Author    Eckhard Wollenweber3-, Anja Wielandb, Klaus HaasbRequires cookie*
 Title    Epicuticular Waxes and Flavonol Aglycones of the European Mistletoe, Viscum album L  
 Abstract    Viscum album, Cuticular Waxes, Flavonol Aglycones Cuticular waxes of Viscum album ssp. album contain oleanolic acid as main constituent, accompanied by aliphatic compounds like alkanes, esters and primary alcohols. A number of flavonol aglycones (methyl ethers of quercetin and kaempferol) have also been identified. Seasonal changes in amount and composition of cuticular waxes and the presence of flavonol aglycones are described and the ecophysiological significance of flavonoids on the surface of the mistletoe is briefly discussed. 
  Reference    Z. Naturforsch. 55c, 314 (2000); received March 1 2000 
  Published    2000 
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 Identifier    ZNC-2000-55c-0314 
 Volume    55 
47Author    Angel Rumbero3, F. J. Arriaga-Ginerb, Eckhard WollenwebercRequires cookie*
 Title    New Constituents of the Leaf and Stem Exudate of Ozothamnus hookeri (Asteraceae)  
 Abstract    Ozothamnus hookeri, Phenolic Fatty Acid Ester, Kaurane Diterpenoids The exudate of Ozothamnus hookeri has been investigated for its non-flavonoid constitu­ ents. A new natural C6-C3 ester of a long chain fatty acid and seven structurally related kaurane-diterpenoids were isolated. Three of the latter are new natural products, too. A rare 8-methoxy flavonol was also identified. 
  Reference    Z. Naturforsch. 55c, 318 (2000); received March 1 2000 
  Published    2000 
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 Identifier    ZNC-2000-55c-0318 
 Volume    55 
48Author    Chalerm Ruangviryachaib, Insa Barelmann3, Regine Fuchs3, Herbert Budzikiewicz3Requires cookie*
 Title    An Exceptionally Large Pyoverdin from a Pseudomonas Strain Collected in Thailand+  
 Abstract    Pseudomonas, Pyoverdin Pf 1547, Siderophore From a Pseudomonas strain obtained from a soil sample collected in Thailand a pyoverdin was obtained containing twelve amino acids in its peptide chain. The structure elucidation is described. 
  Reference    Z. Naturforsch. 55c, 323 (2000); received February 18/March 2 2000 
  Published    2000 
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 Identifier    ZNC-2000-55c-0323 
 Volume    55 
49Author    Maik Münzinger3, Herbert Budzikiewicz3, Dominique Expertb, Corine Enardb, Jean-Marie MeyercRequires cookie*
 Title    Achromobactin, a New Citrate Siderophore of Erwinia chrysanthemi  
 Abstract    Erwinia chrysanthemi, Achromobactin, Siderophore The structure of a citrate siderophore named achromobactin isolated from the culture medium of Erwinia chrysanthemi was elucidated by spectroscopic methods and chemical de­ gradation. 
  Reference    Z. Naturforsch. 55c, 328 (2000); received February 18/March 2 2000 
  Published    2000 
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 Identifier    ZNC-2000-55c-0328 
 Volume    55 
50Author    Javier De Santos3, AnaM. Díaz, Lanza3-*, Lidia Fernández3, Angel RumberobRequires cookie*
 Title    Isoangoroside C, a Phenylpropanoid Glycoside from Scrophularia scorodonia Roots  
 Abstract    Isoangoroside C, Scrophularia scorodonia, Phenylpropanoid Glycoside A new phenylpropanoid glycoside isoangoroside C was isolated from the roots of Scrophu­ laria scorodonia. Its structure was determined on the basis of spectral data as: 3-hydroxy-4-m ethoxy-ß-phenylethoxy-0-a-L-arabinopyranosyl-(1^6)a L-rhamnopyranosyl-(l-^-3)-4-0-Z-feruloyl-ß-D -glucopyranoside. Additionally, one known phenylpropanoid, angoroside C, and five known iridoid glycosides, harpagoside, bartsioside, 8-O-acetyl-harpagide, aucuboside and harpagide were isolated and identified. 
  Reference    Z. Naturforsch. 55c, 333 (2000); received November 18 1999/February 25 2000 
  Published    2000 
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 Identifier    ZNC-2000-55c-0333 
 Volume    55 
51Author    LeneH. Harder, LarsP. ChristensenRequires cookie*
 Title    A New Flavone O-Glycoside and Other Constituents from Wheat Leaves (Triticum aestivum L.)  
 Abstract    Triticum aestivum, Gramineae, C-Glycosylflavones From leaves of Triticum aestivum a new O-glycosylflavone has been isolated together with chlorogenic acid and its 3'-methyl ether and 6 C-glycosylflavones. The structure of the new flavonoid was determined by ID and 2D NMR techniques and other spectral evidence as 5,7-dihydroxy-3',4',5'-trimethoxyflavone-7-0-ß-rutinoside. 
  Reference    Z. Naturforsch. 55c, 337 (2000); received February 24/March 10 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0337.pdf 
 Identifier    ZNC-2000-55c-0337 
 Volume    55 
52Author    Afgan Farooq3, Satoshi TaharaaRequires cookie*
 Title    Oxidative Metabolism of Ambrox and Sclareolide by Botrytis cinerea  
 Abstract    Ambrox (1), a perfumery diterpene, was oxidatively metabolised by a plant pathogenic fungus Botrytis cinerea in a xenobiotic fashion to afford a major product, i.e., lß-hydroxy-8-epiambrox (13) (60%) along with three minor metabolites 3ß-hydroxyambrox (2), sclareolide (5) and 3ß-hydroxysclareolide (7). Sclareolide (5), a cytotoxic diterpenoidal lactone was fer­ mented with the same fungus to yield 3ß-hydroxysclareolide (7) (59%) as a major metabolite together with two minor metabolites characterised as 1-ketosclareolide (15), and 3ß,14-dihy-droxysclareolide (16). 
  Reference    Z. Naturforsch. 55c, 341 (2000); received March 1/March 30 2000 
  Published    2000 
  Keywords    Ambrox, Sclareolide, Botrytis cinerea 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0341.pdf 
 Identifier    ZNC-2000-55c-0341 
 Volume    55 
53Author    Fabio Naro3, MariaG. Tordic, GiorgioM. Giacomettid, Francesco Tomeia, AnnaM. Timperiob, Lello ZollabRequires cookie*
 Title    Metal Binding to Pseudomonas aeruginosa Azurin: a Kinetic Investigation  
 Abstract    The interaction between azurin from Pseudomonas aeruginosa and A g(I), C u(II), H g(II), was investigated as a function of protein state, i.e. apo-, reduced and oxidised azurin. Two different metal binding sites, characterized by two different spectroscopic absorbancies, were detected: one is accessible to Ag(I) and Cu(II) but not to H g(II); the other one binds Ag(I) and Hg(II) but not copper. When added in stoichiometric amount, Ag(I) shows high affinity for the redox center of apo-azurin, to which it probably binds by the -SH group of C y sll2; it can displace Cu(I) from reducedazurin, while it does not bind to the redox center of oxidizedazurin. Kinetic experiments show that Ag(I) binding to the reducedform is four times faster than binding to the apo-form. This result suggests that metal binding requires a conformational rearrangement of the active site of the azurin. Interaction of A g(I) or Hg(II) ions to the second metal binding site, induces typical changes of UV spectrum and quenching of fluorescence emission. 
  Reference    Z. Naturforsch. 55c, 347 (2000); received December 21 1999/February 4 2000 
  Published    2000 
  Keywords    Azurin, Pseudomonas aeruginosa, Metal Binding 
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 Identifier    ZNC-2000-55c-0347 
 Volume    55 
54Author    Nikolai Tuparev, Anelia Dobrikova, Stefka Taneva, Tzvetana LazarovaRequires cookie*
 Title    Bacteriorhodopsin Thermal Stability: Influence of Bound Cations and Lipids on the Intrinsic Protein Fluorescence  
 Abstract    Temperature -induced changes in protein intrinsic fluorescence of native, delipidated and deionized purple membranes are investigated. It is found that the removal of cations most strongly affects the protein and its thermal stability. The denaturation of dei-BR completes at 70 °C, while delipidated and native BR still maintain their native structure at this temper­ ature. Both, the quantum yield and the fluorescence maximum suggest correlation between the Trp-retinal coupling and protein structural stability. The low red shift of the fluorescence maximum caused by increasing of temperature indicates limited unfolding of bacteriorhodop­ sin upon denaturation. 
  Reference    Z. Naturforsch. 55c, 355—360 (2000); received December 27 1999/February 23 2000 
  Published    2000 
  Keywords    Bacteriorhodopsin, Deionization, Delipidation 
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 Identifier    ZNC-2000-55c-0355 
 Volume    55 
55Author    Lutz Schäfer, Jürgen FeierabendRequires cookie*
 Title    Photoinactivation and Protection of Glycolate Oxidase in vitro and in Leaves  
 Abstract    Antioxidants, Glycolate Oxidase, Photoinactivation Glycolate oxidase that was partially purified from pea leaves was inactivated in vitro by blue light in the presence of FMN. Inactivation was greatly retarded in the absence of 0 2. Under aerobic conditions H20 2 was formed. The presence of catalase, GSH or dithiothreitol protected glycolate oxidase against photoinactivation. Less efficient protection was provided by ascorbate, histidine, tryptophan or EDTA. The presence of superoxide dismutase or of hydroxyl radical scavengers had no, or only minor, effects. Glutathione suppressed H20 2 accumulation and was oxidized in the presence of glycolate oxidase in blue light. Glycolate oxidase was also inactivated in the presence of a superoxide-generating system or by H20 2 in darkness. In intact leaves photoinactivation of glycolate oxidase was not observed. How­ ever, when catalase was inactivated by the application of 3-amino-l,2,4-triazole or depleted by prolonged exposure to cycloheximide a strong photoinactivation of glycolate oxidase was also seen in leaves. In vivo blue and red light were similarly effective. Furthermore, glycolate oxidase was photoinactivated in leaves when the endogenous GSH was depleted by the application of buthionine sulfoximine. Both catalase and antioxidants, in particular GSH, appear to be essential for the protection of glycolate oxidase in the peroxisomes in vivo. 
  Reference    Z. Naturforsch. 55c, 361—372 (2000); received March 6/March 24 2000 
  Published    2000 
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 Identifier    ZNC-2000-55c-0361 
 Volume    55 
56Author    Fumio Matsuda, Hisashi Miyagawa, TamioU. EnoRequires cookie*
 Title    ß-l,3-Glucooligosaccharide Induced Activation of Four Enzymes Responsible for iV-/?-coumaroyloctopamine Biosynthesis in Potato {Solanum tuberosum cv.) Tuber Tissue  
 Abstract    ß-l,3-Glucooligosaccharide, /V-/?-Coumaroyloctopamine, Solanum tuberosum Potato tuber disks, when treated with laminarin, a ß-l,3-glucooligosaccharide from Lami-naria digitata, accumulate a hydroxycinnamoyl amide compound, /V-p-coumaroyloctopamine (p-CO). The biosynthesis of p -CO was investigated by feeding experiments, in order to show that the precursors of /V-p-coumaroyl and octopamine moieties of p-C O are L-phenylalanine and L-tyrosine, respectively. The treatment of potato tuber tissue with laminarin resulted in elevated activities of four enzymes which are putatively involved in p-C O biosynthesis: phenylalanine ammonia lyase (PAL; EC 4.3.1.5), 4-hydroxycinnamic acid:CoA ligase (4CL; EC 6.2.1.12), hydroxycinnamoyl-CoA:tyramine /V-(hydroxycinnamoyl)transferase (THT; EC 2.3.1.110) and tyrosine decarboxylase (TyrDC; EC 4.1.1.25). Among these, the response of TyrDC was specific to laminarin treatment, thus indicating that the regulation of TyrDC activity is critical for the accumulation of p -CO in potato tuber tissue. 
  Reference    Z. Naturforsch. 55c, 373—382 (2000); received December 6 1999 
  Published    2000 
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 Identifier    ZNC-2000-55c-0373 
 Volume    55 
57Author    Norbert Grotjohann3, PingH. Eb, GeorgH. Schmid3-Requires cookie*
 Title    Capacity of Enzymes of the Euphorbiacea Aleurites montana Involved in C 0 2- Fixation, Compared to Plants Having C3-, C4-and Crassulacean Acid Metabolism  
 Abstract    Dedicated to Professor Wilhelm Menke on the occasion o f his 90th birthday Aleurites montana, Phosphoenolpyruvate Carboxylase, Malic Enzyme, Malate Dehydrogenase, Ribulose Bisphosphate Carboxylase Capacities of phosphoenolpyruvate carboxylase (PEP-Co), ribulose bisphosphate carbox­ ylase (Rubisco), NADP+ malic enzyme (ME) and of malate dehydrogenase (MDH) were measured in the Euphorbiacea Aleurites montana, grown under 700 ppm C 0 2 for four weeks prior to enzyme extraction. For comparison Bryophyllum daigremontiana (CAM), Saccharum officinarum (C4) and Capsicum frutescens (C3) were treated in the same way. PEP-Co capac­ ity of Aleurites was in the range of 12-, that of Capsicum approx. 26 nmol x min-1 x mg protein-1, without significant influence of the light period or C 0 2-treatment. In contrast, the activity of the enzyme from Saccharum was. depending on the duration of light, 160-respec­ tively 96 times higher than that of the tung-oil tree. In Bryophyllum a rather low activity in the morning was increased during the day to approx. 230 nmol x min-1 x mg protein-1 in plants grown in the greenhouse and to approx. 115 nmol x min-1 x mg protein-1 in those from the growth chamber. Malate was hardly detectable in extracts of Aleurites, whereas it was high in Bryophyllum, depending on the light period. The ratio of average PEP-Co to Rub-Co capacity was high for the CAM-plant (20:1), somewhat lower for sugar cane (10:1), but almost at equality for Aleurites (0.9:1) and chilli (0.8:1). For the NADP+ malic enzyme, low capacity (20 to 28 nmol x min-1 x mg protein-1) was found for Aleurites and for Capsi­ cum!, whereas it was 10 to 17 times higher in Saccharum. In Bryophyllum , the activity was up to 80 nmol x min-1 x mg p r o t e in , dependent on light period. MDH capacity was ex­ tremely high in all plants investigated. Highest rates (10 -2 0 |j,mol x min-1 x mg protein-1), were obtained for Bryophyllum , followed by sugar cane and Capsicum with 5 -8 [.imol x min-1 x mg protein-1. Again, the lowest capacity was found in extracts of Aleurites with approx. 1.3 to 1.6 ^unol x min-1 x m protein-1. Thus, in Aleurites montana no indication for C4-or Crassulacean acid metabolism was obtained. Therefore, the earlier observed very efficient uptake of C 0 2 cannot be explained by a high expression of the PEP-Co protein, known to occur in CAM-and C4-plants. 
  Reference    Z. Naturforsch. 55c, 383—391 (2000); received March 2/April 7 2000 
  Published    2000 
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 Identifier    ZNC-2000-55c-0383 
 Volume    55 
58Author    Adriana Dos, Passos Lemos, CarlosE. Peres-Sampaio, Horácio Guimarães-Motta, JersonL. Silva, JoséR. Meyer-FernandesRequires cookie*
 Title    Effects of Naturally Occurring Polyols and Urea on Mitochondrial F0FjATPase  
 Abstract    Polyols, Mitochondrial F0F1-ATPase. Urea We show that urea inhibits the ATPase activity of MgATP submitochondrial particles (MgATP-SMP) with Ki = 0.7 m . probably as a result of direct interaction with the structure of F()F |-ATPase. Counteracting compounds (sorbitol, mannitol or inositol), despite slightly (10-20%) inhibiting the ATPase activity, also protect the F()Fr ATPase against denaturation by urea. However, this protection was only observed at low urea concentrations (less than 1.5 m), and in the presence of three polyols, the Kj for urea shift from 0.7 m to 1.2 m . Urea also increases the initial activation rate of latent MgATP-SMP in a dose-dependent-manner. However, when the particles (0.5 mg/ml) were preincubated in the presence of 1 m , 2 m or 3 m urea, a decrease in the activation level occurred after 1 h, 30 and 10 min, respectively. At high MgATP-SMP concentration (3 mg/ml) a decrease in activation was observed after 2 h, 1 h and 20 min, respectively. These data indicate that the effect of urea on the activation of MgATP-SMP depends on time, urea and protein concentrations. It was also observed that polyols suppress the activation of latent MgATP-SMP in a dose-dependent manner, and protect the particles against urea denaturation during activation. We suppose that a decrease in membrane mobility promoted by interactions of polyols with phospholipids around the F()Fr ATPase may also increase the compactation of protein structure, explaining the inhibi­ tion of natural inhibitor protein of ATPase (IF,) release and the activation of the enzyme. 
  Reference    Z. Naturforsch. 55c, 392—398 (2000); received December 8 1999/February 18 2000 
  Published    2000 
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 Identifier    ZNC-2000-55c-0392 
 Volume    55 
59Author    Olivier Raymond, Jean-Louis Fiasson, Maurice JayRequires cookie*
 Title    Synthetic Taxonomy of Rosa Races Using ACT-STATIS  
 Abstract    Fifteen Rosa cultivated races were described by means of phenotypic frequencies (11 ta­ bles). Two groups of correlated contingency tables were identified by ACT-STATIS (Analyse Conjointe de Tableaux -Structuration de Tableaux ä Trois Indices de la Statistique) inter­ structure analysis. Three data sets appeared to be independent from the others. Typologies of races were obtained after ACT-STATIS compromise analyses for the two groups of corre­ lated tables, and after Principal Component Analyses for the independent data sets. Each typology was original and variously influenced by genealogical structure, mutation or artifi­ cial selection pressures. A weighted synthesis was attempted in order to build a taxonomy of races taking into account these diversity factors. The good agreement between the resulting classification and the assumptions about the history of Rosa domestication advocated for a wider utilization of ACT-STATIS and RV coefficient when the relationships between individ­ uals or populations have to be studied on the basis of their similarities. 
  Reference    Z. Naturforsch. 55c, 399—409 (2000); received January 24/February 28 2000 
  Published    2000 
  Keywords    Rosa, ACT-STATIS, Taxonomic Congruence 
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 Identifier    ZNC-2000-55c-0399 
 Volume    55 
60Author    Adalberto Bonincontro3, Stefania Cinellib, Giuseppe Onorib, Gianfranco RisuleocRequires cookie*
 Title    Instability of Three-Dimensional Structures in Ribosomal Cores Evidenced by Microcalorimetric Studies  
 Abstract    Ribosomal Cores, M icrocalorimetry In this paper we show a microcalorim etric investigation carried out on the so-called cores, i. e. ribosomes deprived of select proteins by LiCl treatm ent. Thermal degradation of native ribosomes gives rise to two thermal transitions occurring at different temperatures. In the cores the high temperature peak persists even after treatm ent at very high ion strength (2 m LiCl). This strongly suggests the existence of a very stable structure that was previously observed also in particles treated with agents that hydrolyze the RN A moiety. The low tem ­ perature peak gradually but dramatically decreases even though it never disappears com ­ pletely This indicates that the treatm ent to obtain ribosomal cores does not cause complete unfolding of the particle but only the destabilization of a structural three-dimensional domain present in native ribosomes. These data are discussed in the light of previous results obtained by dielectric spectroscopy and microcalorim etric studies on ribosomal particles. 
  Reference    Z. Naturforsch. 55c, 410 (2000); received November 16 1999/M arch 1 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0410.pdf 
 Identifier    ZNC-2000-55c-0410 
 Volume    55 
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