bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Cembranoid from Tobacco, IV *
Authors: Heemann Volker , Bylov Anne-Marie , Hass Werner , Kahre Claudius , Seehofer Friedlieb 
Published: August 2018

Abstract
4,8-Dimethyl-11-isopropyl-6,8-dihydroxy-pentadeca-4,9-dien-14-on-1-al (3) was identified as a new natural product from tobacco. 3 was isolated from the surface gum of fresh tobacco. The spectral data, chemical properties and the synthesis 3 are given.
Studies on the O2 Evolution under Flash Light Illumination in Preparations of Anacystis nidulans
Authors: Pistorius E. K. , Schmid G. H. 
Published: August 2018

Abstract
The O2 yield under flash light illumination in preparations of Anacystis nidulans was examined in the presence of redox components such as ferricyanide and ferrocyanide. When ferricyanide (1 mᴍ) was added to the lyophilized, lysozyme treated and EDTA washed cells of A. nidulans the familiar Joliot-Kok oscillalion with maximum on the third flash and periodicity of four was observed (in the presence of added CaCl2 and MnCl2). However, when the ferricyanide con­centration was increased to about 8 mᴍ , a reduction of the O2 evolution under flash illumination was observed, and an O2 uptake could clearly be seen under the first and second flash. This O2 uptake was inhibited by DCMU and o-phenanthroline, but was not influenced by KCN or salicylhydroxamic acid. As ferrocyanide was progressively added to 1 mᴍ ferricyanide, the oscillations faded out and the steady-state O2 evolution decreased. Light would progressively increase the O2 evolution and reduce the damping of the oscillations.
Two patterns of O2 evolution under short saturating light flashes were observed with these Anacystis preparations on first illumination in the presence of cations but in the absence of ferricyanide. One pattern corresponded to the typical pattern which has been repeatedly described in the literature, but the second pattern gave the indication of an initial “over-reduced” state of the photosystem II reaction center. With suitable procedures the two patterns were interchangeable. Moreover, the effect of ʟ-arginine on the flash pattern was examined. The results are discussed in connection with the possible dual function of the previously described flavin protein as an ʟ-amino acid oxidase and as a component of the O2 evolving reaction center (E. K. Pistorius and H. Voss, Eur. J. Biochemistry 126,203-209 (1982)).
Light Induced Changes in the Conformation of Spinach Thylakoid Membranes as Monitored by 90° and 180° Scattering Changes: A Comparative Investigation
Authors: Coughlan S. J. , Schreiber U. 
Published: August 2018

Abstract
A series of investigations on light induced thylakoid membrane conformational changes has been carried out using scattering changes measured either at 90° or 180° (transmittance changes) as criteria for changes in membrane structure upon illumination. These two phenomena were found to react similarly to a range of photosynthetic inhibitors, to changes in the ionic (Mg2+, H+) concentration, and to have similar difference spectra. However, it was found possible to distinguish these two phenomena by the differences in the kinetics of the light induced rise times. This could be shown most clearly using an Aminco DW2 spectrophotometer with the measuring beam deflected through 90° by front face mirrors. The dark decay time of the two scattering changes was similar.
These results are discussed in relation to the hypothesis that the light induced narrow angle 90° scattering response represents microconformational membrane changes in response to proton uptake, and the 180° scattering changes represent a mixed response including changes in the stacking of thylakoids.
Haemolytic Properties of Cereal 5-n-Alk(en)ylresorcinols
Authors: Kozubek Arkadiusz 
Published: August 2018

Abstract
The haemolytic activity of 5-n-alk(en)ylresorcinols is temperature dependent and correlated to their transition temperatures. The values of the parameters describing the 5-n-alk(en)yl-resorcinol-induced red blood cell lysis indicate strong affinity of the compounds to the membrane and their high lytic capacity. The affinity of the compounds for the membrane decrease with the increasing quantity of the molecules incorporated into the erythrocyte membrane and is much higher for saturated resorcinols than unsaturated ones. The amount of 5-n-alk(en)ylresorcinol molecules bound to the membrane at a hundred percent lysis is about eighty times and eleven times (for alkyl and alkenyl derivatives respectively) higher than at zero percent lysis. Estimated free energy of erythrocyte lysis was similar for alkyl and alkenyl derivatives of resorcinol provided the preparation of the resorcinolic suspensions above their transition temperatures.
Feeding and Molt Inhibition by Azadirachtins A, B, and 7-Acetyl-azadirachtin A in Rhodnius prolixus Nymphs
Authors: Garcia Eloi S. , Azambuja Patricia de , Forster Hans , Rembold Heinz 
Published: August 2018

Abstract
The antifeedant and antimolting effects of azadirachtins A and B, and of a synthetic derivative, 7-acetyl-azadirachtin A were examined. Given through a blood meal, the effective dose (ED50) for the antifeedant effect ranged from 25 to 30 μg/ml of blood for the three compounds. ATP, a phagostimulant, also given orally, reversed the antifeedant action of azadirachtin A. The ED50 values for molt inhibition were 0.04, 0.015, and 0.45 (μg/ml of blood for azadirachtins A, B, and 7-acetyl-azadirachtin A, respectively. The mechanisms of feeding and molt inhibitions by azadirachtin A B, and its 7-acetyl-azadirachtin A derivative are discussed.
A Micromethod for Rapid Quantitative Determination of Phosphonate Phosphorus
Authors: Kapoulas Vassilios M. , Mastronicolis Sofia K. , Nakhel Ibrahim C. , Stavrakakis Helen J. 
Published: August 2018

A rapid method for initial quantitative estimation of the phosphate present in compound containing a carbon-phosphorus bond is described.
Two phosphorus assays are employed. One assay is for total phosphorus, which can be determined by digesting with perchloric acid and the other assay is for total non phosphonate phosphorus which can be determined by digesting with sulfuric acid simultaneously. The difference between total phosphorus and the non phosphonate phosphorus determined represents the amount of phosphorus present in a carbon-phosphorus linkage in a crude phospholipids sample
Mechanisms of Adriamycin-Dependent Oxygen Activation Catalyzed by NADPH-Cytochrome c-(Ferredoxin)-Oxidoreductase
Authors: Paur Eva , Youngman Richard J. , Lengfelder Edmund , Elstner Erich F. 
Published: August 2018

Under aerobic conditions, O2 uptake and production of O2
- and H2O2 by isolated NADPH - cytochrome c-(ferredoxin)-oxidoreductase from Euglena gracilis was strongly stimulated by adriamycin. Further stimulation was not observed with 0.1 mᴍ Fe3+-EDTA. Methionine fragmentation (measured as ethylene release), as a reliable indicator for the formation of OH- radical-like oxidants under aerobic conditions (100 μmol O2 in a 10 ml reaction vessel) was strongly stimulated by 0.1 mᴍ Fe3+-EDTA or, in the absence of iron, by partial anaerobiosis (1 μmol O2 per vessel). The highest rate of methionine fragmentation was observed under anaerobic conditions in the presence of both reduced adriamycin and added H2O2.
Aerobic methionine fragmentation in the presence of adriamycin and Fe3+-EDTA was inhibited by superoxide dismutase and catalase by more than 90%, while methionine fragmentation under semianaerobiosis in the absence of Fe3+-EDTA was inhibited by superoxide dismutase to only about 50%, while catalase again inhibited by more than 90%. These results indicate that the adriamycin-catalyzed production of a strong oxidant appears to be governed by different mechanisms depending on oxygen availability; namely the production of a Fenton-type oxidant driven by adriamycin-catalyzed superoxide formation and also, the formation of the “crypto-OH- radical” by direct electron donation from the adriamycin semiquinone radical to H2O2 under oxygen limiting conditions
The Crystal Structure of Anhydrous Xanthosine Displays Intramolecular O(2′)H ... O(3′) Hydrogen Bond
Authors: Lesyng Bogdan , Marck Christian , Saenger Wolfram 
Published: August 2018

Abstract
From an equimolar dipeptide/xanthosine mixture in water/methanol, only the nucleoside crystallized in anhydrous form, space group P212121 with a = 17.406 (5) Å, b = 12.378 (4), c = 5.350 (2) Å, Z = 4, C10H12O6N4, FW = 284.26, Dx = 1.639 g · cm-3. The structure was determined by direct methods on the basis of 984 X-ray data and refined to an agreement index of R = 3.9%. Xanthosine occurs in the syn conformation with χ = -132.7° which is stabilized by an intramolecular hydrogen bond N (3) - H ... O(5′). The pseudorotation parameters for sugar puckering are P = 156° and τm = 38.7° corresponding to C(2′)-endo form. The crystal packing of xanthosine in anhydrous and dihydrate modifications are very different, yet the molecular conformations are similar. In the anhydrous form, an unusual intramolecular hydrogen bond O (2′) - H ... O(3′) is observed.
Effects of Vitamin A in the Presence of Vitamins D3, E, K, on Red Cell Membrane Structure
Authors: Cicero R. , Callari D. , Guidoni L. , Viti V. , Scalia M. , Maida I. , Billitteri A. , Sichel G. 
Published: August 2018

Abstract
The incubation of erythrocyte ghosts with mixtures of vitamins A + D 3, A + E, A + K1 , produces decrease or increase of fluorescence anisotropy r of the DPH probe, depending on the vitamin/vitamin ratio. We found a correlation between the order parameter S and cell fusion phenomena observed by phase contrast microscopy.
Notizen: In vivo Metabolism of [4-13C]Phenacetin in an Isolated Perfused Rat Liver Measured by Continuous Flow 13C NMR Spectroscopy
Authors: Albert Klaus , Kruppa Gerd , Zeller Klaus-Peter , Bayer Ernst , Hartmann Franz 
Published: August 2018

Abstract
Metabolism, [4-13C]Phenacetin, Continuous Flow 13C NMR Continuous flow 13C NMR spectroscopy has been used for the first time to monitor the metabolism of a 13C labeled drug in an isolated liver. Continuous and almost immediate information on the metabolite formation could be obtained using 13C labeled phenacetin without alteration of the biological system. The data are consistent with those observed by conventional techniques (HPLC, aliquot 13C NMR measurements). From the biological point of view the sensitivity of continuous flow 13C NMR spectroscopy is still low (10-3 ᴍ). The results presented demonstrate however that non-invasive and non-radio-active real time monitoring of drug metabolism in intact organs is possible.
Induced and Constitutive Isoflavonoids in Phaseolus mungo L. Leguminosae
Authors: Adesanya Saburi A. , O’N eill Melanie J. , Roberts Margaret F. 
Published: August 2018

Abstract
Sixteen isoflavonoids have been isolated from the black gram. Phaseolus mungo L. (syn. Vigna mungo) following treatment with aqueous CuCl2. These include 12 known isoflavonoids: genistein. 2′-hydroxygenistein. 2′-hydroxydaidzein, kievitone, dalbergioidin, cyclokievitone. 5-deoxykievitone, 2′-hydroxydihydrodaidzein, isoferreirin, aureol, glycinol and demethylvestitol. In addition, kievitone hydrate, which was previously known only as a fungal metabolite of kievitone, was isolated together with 3 novel natural isoflavanones which were characterized as 4′-O-methylkievitone, cyclokievitone hydrate and 5-deoxykievitone hydrate.
Phospholipids and Glycerides Composition during Spheroplasts Formation of Mycobacterium smegmatis ATCC 14468
Authors: Murty M. V. V. S. , Venkitasubramanian T. A. 
Published: August 2018

Abstract
The phospholipids and glycerides composition of spheroplasts of Mycobacterium smegmatis ATCC 14468 was examined. The percent total phospholipids in total lipids as well as cardio-lipin were found to be higher in spheroplasts as compared to their parent forms. Increase in cardiolipin and free fatty acids content and decrease in triglycerides levels were observed during spheroplasts formation. The results suggest that increase in cardiolipin content in sphero­ plasts is an adaptational change concomittant with the loss of cell walls.
Cell Fusion by Simulated Atmospheric Discharges: Further Support for the Hypothesis of Involvement of Electrofusion in Evolution
Authors: Küppers Gottfried , Diederich Karl-Josef , Zimmermann Ulrich 
Published: August 2018

Abstract
Electrofusion of mesophyll cell protoplasts of Avena sativa was induced by simulated atmospheric discharges. It is shown both experimentally and theoretically that the potential differences which occur at quite long distances from the point of lightning stroke are large enough to induce fusion. Besides electromagnetic waves which are emitted during lightning (G. Küppers and U. Zimmermann, FEBS Lett. 164, 323 (1983)) cell fusion may have also occurred directly by means of the voltage built-up on the earth during evolution in response to a lightning stroke.
The Cellular Substrate: A Very Important Requirement for Baculovirus in vitro Replication
Authors: Miltenburger Herbert G. , Naser Werner L. , Harvey Jeanne P. , Huber Jürg , Huger Alois M. 
Published: August 2018

Abstract
We established more than 200 primary cell lines of Cydia pomonella (codling moth). 81 of them were selected and screened for replication of two baculoviruses (from two different subgroups): the Choristoneura murinana NPV and the Cydia pomonella GV. Although all these cell lines had been derived from the same insect species, they varied largely in their response to challenge with the NPV. Most of them showed CPE or produced different amounts of poly-hedra. Interestingly, we also found a few cell lines that were permissive for GV replication. To our knowledge this is the first time that GV replication in cell lines has been obtained. Our results show that cell line properties are most important for baculovirus in vitro replication.
Determination of 4-Pregnene-3-ones in Thymus Tissue Sam ples by High Performance Liquid Chromatography*
Authors: Reisch Johannes , Norrenbrock Josef 
Published: August 2018

Abstract
A high performance liquid chrom atography method for determining the levels of 4-pregnene-3-ones in tissue containing fat, e.g. in thymus is reported. Following the extraction with chloroform/methanol the fat has been separated from the steroidal-fraction by using disposable extraction-columns. The steroidal-fraction has been analysed in two separation systems, on a RP18-column with a methanol/water gradient and on an amino column with a isopropanol/hexane gradient. The applicability of the described method is demon­ strated with calf thymus samples.
Phospholipid Transfer from ER to the Peribacteroid Membrane in Soybean Nodules
Authors: Mellor R. B. , Christensen T. M. I. E. , Bassarab S. , Werner D. 
Published: August 2018

Organelle membranes subfractionated from nodules of Glycine max differed in lipid compo­sition. Of the enzymes assembling phospholipids, choline kinase (EC 2.7.1.32) was recovered in the cytoplasmic fraction whereas CDP choline 1,2-diacylglyceride choline phosphotransferase (EC2.7.8.2) was located in the ER. When methyl [14C]CDP choline was supplied to nodules in vivo radioactivity was found in the ER. On longer labelling periods [14C]phosphatidylcholine spread into denser regions of the gradient, including the peribacteroid membrane (which surrounds the Rhizobium japonicum symbiont). [14C]Phosphatidylcholine was a notable component of such membranes.
Adenosine triphosphatase (EC 3.6.1.3) activity in the peribacteroid membrane fraction was compared to that of other major organelle fractions. The peribacteroid membrane ATPase was equally active on pH 6.0 and 8.0, was stimulated by K+ and inhibited by DES, DCCD and MoO4. In these respects it was more similar to the ATPase activity in the ER and mitochondria than in tonoplast or cytoplasm.
The results are discussed in relation to modes of peribacteroid membrane biogenesis, in­cluding enzyme modification.
Effects of Carbohydrates on the Ion Conductance of the Hemocyanin Channel
Authors: Menestrina Gianfranco , Pasquali Flavia 
Published: August 2018

Abstract
The effects of glucose and sucrose on the ionic conductance properties of the channel formed by Megathura crenulata hemocyanin in planar lipid bilayers have been studied using membranes of different compositions. It was found that glucose at high concentrations strongly affects the time constants of the current relaxations observed in membranes containing many channels after a step in the voltage clamp from ground to a positive value. At much lower concentrations both sucrose and glucose strengthened the binding of Ba2+ to the protein, what in turn has the effect to shift the conductance voltage curve of the pore towards negative potentials. The possible mechanism underlying these effects and the analogies with other studies on the interaction of sugars and alcohols with proteins have been discussed.
Photodestruction of Propionibacterium acnes Porphyrins
Authors: Melø T. B. , Reisaeter G. , Johnsson A. , Johnsson M. 
Published: August 2018

Abstract
The fluorescence spectra of colonies of Propionibacterium acnes were studied under various experimental conditions.
The spectra contained peaks at 580 nm and 620 nm. These bands were due to two different components; the 580 nm component was likely to be a metalloporphyrin, and there are indications that the 620 nm component could be a coproporphyrin.
The 580 nm fluorescence was destroyed by the combined action of light and oxygen (no destruction under strict anaerobic conditions). A dark period interrupting the bleaching light stopped the destruction of this component for the time of the dark period.
The initial production of the 620 nm component was due to the oxygen exposure. Upon light irradiation this component was later destroyed by the combined action of oxygen and light.
Identification of Cyclic Enolethers from Insects: Alkyldihydropyranes from Bees and AIkyldihydro-4H-pyran-4-ones from a Male Moth*
Authors: Francke W. , Mackenroth W. , Schroder W. , Schulz S. , Tengö J. , Engels E. , Engels W. , Kittmann R. , Schneider D. 
Published: August 2018

Abstract
Mass spectrometric fragmentation patterns of alkyl-3,4-dihydro-2H-pyranes and alkyl-2,3-dihydro-4H-pyran-4-ones are described. Through GC/MS analyses, respective compounds showing unbranched carbon skeletons are identified for the first time as volatile signals of social and solitary bees and of the male moth Hepialus hecta L.
Further Evidence for a Functional Relationship between L-Amino Acid Oxidase Activity and Photosynthetic Oxygen Evolution in Anacystis nidulans. Effect of Chloride on the Two Reactions
Authors: Pistorius Elfriede K. 
Published: August 2018

Abstract
The ʟ-amino acid oxidase from Anacystis nidulans is inhibited by cations as well as anions. The inhibition by cations has been previously described (E. K. Pistorius, Eur. J. Biochem. 135, 217-222 [1983]). We have shown that the order of effectiveness was M3+ > M2+ > M+, when e.g. La3+, Ca2+ and K+ were compared. However, in the concentration range where the monovalent cations inhibited, the inhibition was not entirely due to the cation, but an influence of the anion could also be observed. When monovalent anions were compared as the corresponding sodium salts, the order of effectiveness was SCN- > NO3
- > CL-, Br- > I- > F- > HCOO- > CH3COO- . The inhibition of the ʟ-amino acid oxidase activity by the various salts was strongly influenced by the pH of the reaction mixture. It could be shown that the inhibition by cations increased in the alkaline pH region, while the inhibition by anions increased in the acidic pH region.
Our previous results have also shown that a functional relationship might exist between ʟ-amino acid oxidase activity and photosynthetic O2 evolution (E. K. Pistorius and H. Voss, Eur. J. Biochem. 126, 203-209 [1982]). Since the water-splitting complex of photosystem II is affected by a number of anions, although only Cl- and Br- lead to activation of O2 evolution, we investigated whether a correlation could be obtained between the anion effect on the ʟ-amino acid oxidase and on photosynthetic O2 evolution. The results show that those anions which have a higher affinity for the enzyme than CL- or Br-, are especially effective in causing inactivation of the O2 evolution. Moreover, we show that ʟ-arginine which is a substrate of the ʟ-amino acid oxidase, and Cl- have antagonistic effects on the ʟ-amino acid oxidase reaction and on photosynthetic O2 evolution. We suggest that this flavoprotein with ʟ-amino acid oxidase activity is modified by Ca2+ and CL- in such a way that it can now interact with Mn2+ and catalyze the water-splitting reaction of photosystem II.
Preparation of an Enzyme Associated with Carthamin Formation in Carthamus tinctorius L
Authors: Saito Koshi , Takahashi Yoshiyuki , Wada Mizu 
Published: August 2018

Abstract
An enzyme associated with carthamin formation in Carthamus tinctorius L. (carthamin-synthe-sizing enzyme) was isolated from the soluble protein extract of the hypocotyl tips of the etiolated seedlings and purified up to 157-fold by the procedures applying (NH4)2SO4 fractionation, Ca(CH3CO2)2 precipitation, protamine sulfate treatment, Celite adsorption chromatography, and Sephadex G-100 gel filtration. Results from atomic absorption spectral analysis of the enzyme protein showed to contain K as a major component, and Ca and Mg as minor ones. Fe, Cu, and Mn could not be detected in the preparation. At pH 4.8 in 50.0 mᴍ acetate buffer, the partially purified enzyme reacted positively with a flame-coloured precarthamin to produce a reddish product in open cuvettes with incubation medium. The reaction product was identified as carthamin by examining its colour, chromatographic mobilities in different developing solvents and spectroscopic properties inclusive shifts, often by comparing with those of an authentic specimen. Anaerobic incubation reduced the enzyme activity, while exogenously applied O2 slightly enhanced the catalytic rate of carthamin formation. The enzyme was sensitive to phosphorus sub­ stances. Among those compounds tested at 1.2 mᴍ level, orthophosphate showed the most striking inhibitory action on the enzyme. Metal ions affected on the enzyme activity by different extents. Mn2+ stimulated the enzyme reaction, while Cu2+ and Mo6+ exhibited reverse effects. Fe2+, Fe3+, Zn2+, Mg2+, and Co2+ were also unfavourable to the enzyme catalyzed carthamin formation. The preparation of the carthamin-synthesizing enzyme showed no activity of polyphenol oxidase or peroxidase under the conditions specifically designed for detecting both enzyme activities.
Formation and Decay of the Vanadate Complex of the Sarcoplasmic Reticulum Calcium Transport Protein
Authors: Medda Pankaj , Hasselbach Wilhelm 
Published: August 2018

Abstract
The calcium free sarcoplasmic reticulum calcium transport ATPase incorporates in the presence of magnesium ions approx. 8 nmol monovanadate per mg protein, indicating the formation of a complex containing one vanadate residue per enzyme molecule. On ligand-removal or dilution, the saturated enzyme complex displays biphasic decay kinetics, while the unsaturated complex slowly dissociates monophasically. - Ligand competition by raising the concentrations of unlabeled vanadate results in a progressive decrease of the dissociation rate of the unsaturated enzyme. The complicated dissociation kinetics indicate a sequential mode of interaction between two ligand binding sites. The one to one stoichiometry of the complex suggests that the two sites are located at adjacent ATPase molecules. - It appears unlikely that the decay of the enzyme, vanadate complex is retarded by the formation of a stable quaternary complex between the enzyme, magnesium, mono-and polyvanadate.