bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluorescence Energy Transfer between ATPase Monomers in Sarcoplasmic Reticulum Reconstituted Vesicles, in the Presence of Low Concentrations of a Nonionic Detergent
Authors: Champeil Philippe , Rigaud Jean-Louis , Gingold Marcel Pierre 
Published: August 2018

Abstract
We measured fluorescence energy transfer between ATPase monomers labeled with either a donor or an acceptor fluorophore, in order to test the hypothesis that the presumably oligomeric sarcoplasmic reticulum ATPase would dissociate into monomers within the membrane on the addition of low nonsolubilizing amounts of a nonionic detergent, C12E18. We found that at low nonsolubilizing detergent concentrations below the critical micellar concentration (c.m.c.), there was indeed direct interaction between the detergent and the protein; however, only solubilizing detergent concentrations reduced fluorescence transfer to a minimum. Considering the current literature, fluorescence energy transfer proved insufficient, at the present time, to confirm or reject the hypothesis.
On the Essential Oil Components from Humulus lupulus L. var. neomexicanus Nels. & Cockerell. I. Contribution
Authors: Knobloch Karl , Paulini Hubert , Eley Claudia , Eley James H. , Ziegler Erich , Brandauer Herbert , Michaelis Karl , Vostrowsky Otto 
Published: August 2018

Abstract
The essential oil of strobiles from Humulus lupulus L. var. neomexicanus Nels. & Cockerell, grown in the semi-arid climate of Central Colorado, was isolated by steam distillation. A characteristic seasonal dependence of oil production was observed over two vegetation periods. - The main components of the essential oil were identified structurally by means of GC and GC-MS analysis. About 40 different compounds, including monoterpenoic hydrocarbons and alcohols, ketones, methylesters of saturated and unsaturated carboxylic acids were detected. Other sub­ stances were esters of short chain acids with monoterpene alcohols, plus sesquiterpene hydro­carbons.
Vorstufen cyclischer Polysulfide in den Samen von Parkia speciosa Hassk. / Precursors of Cyclic Polysulphides in Seeds of Parkia speciosa Hassk.
Authors: Susilo Rudy , Gmelin Rolf 
Published: August 2018

Abstract
Two sulphur containing amino acids, dichrostachinic acid and djenkolic acid, and one sulphur containing imino acid, thiazolidine-4-carboxylic acid, have been isolated from the seeds o f Parkia speciosa Hassk. Dichrostachinic acid and djenkolic cyclic polysulphides in Parkia speciosa Hassk.
Herbicides which Inhibit Electron Transport or Produce Chlorosis and Their Effect on Chloroplast Development in Radish Seedlings II. Pigment Excitation, Chlorophyll Fluorescence and Pigment-Protein Complexes
Authors: Buschmann C. , Grumbach K. H. 
Published: August 2018

Abstract
DCMU, bentazon, amitrole and SAN 6706 affected the formation of the pigment-protein complexes and caused drastic alterations in the absorption of light and in the transfer of the absorbed energy in the antennae systems. Bentazon and DCMU, photosystem II inhibitors, did not change the pigment absorption and fluorescence excitation spectra. After application of both herbicides the long wavelength fluorescence emission band at 740 nm was reduced similar as in young developing leaves. Although DCMU and bentazon inhibit the photosynthetic electron transport at the same site, bentazon mainly suppressed the formation of the photosystem I complexes CP 1 a and CP 1 while DCMU mainly reduced the photosystem II complex CPa. Bentazon specifically enhanced the formation of LHCP3. This may be important for the increased grana stacking in plastids from bentazon treated plants.
The bleaching herbicides amitrole and SAN 6706 inhibited the formation of carotenoids leading to an accumulation of lycopene, phytofluene and phytoene, while the accumulation of chlorophylls was suppressed. This bleaching effect was most pronounced during growth under higher intensities of light. In weak light (100 lux) amitrole reduced the long wavelength fluorescence maximum but the fluorescence excitation was not affected. With amitrole at 2000 lux and SAN 6706 at 100 lux the long wavelength emission band was further decreased and the fluorescence excitation spectra point to a less efficient energy transfer to chlorophyll a. The fluorescence spectra changed due to herbicide treatment resembled those of not yet fully developed leaves. In contrast to the photosystem II herbicides the bleaching herbicides amitrole and SAN 6706 had a similar effect on the formation of pigment-protein complexes. After growth at 2000 lux both herbicides suppressed the formation of the photosystem I complex CP 1 a and the photosystem II complex CPa. At 100 lux only the formation of CPla was affected.
Except for DCMU all herbicides assayed primarily changed the formation of photosystem I.
Variation in cephalic volatile substances in relation to worker age and behavior in the stingless bee, scaptotrigona postica
Authors: Francke W. , Schröder W. , Engels E. , Engels W. 
Published: August 2018

Head extracts of adult workers of the Brazilian stingless bee Scaptotrigona postica (Trigonini, Meliponinae: Apidae) were analysed for volatile substances by gas chrom atography/ mass spectroscopy. Individual worker bees performing clearly defined tasks and representing five age groups were collected. A total of 36 compounds was identified, 22 of which had not been previously described for a Trigona species.
The major components are 2-heptanol, 2-tridecanone, 2-pentadecanone, Z-5-tetradecenylbutanoate and Z-7-hexadecenylbutanoate. 11 of the 36 compounds increase in concentration with age, but only 2 decrease. The other substances are present in more or less constant concentrations. These data are discussed assuming more complicated pheromone-m ediated interactions within an age-dependent polyethism between old workers acting inside and outside the nest than between young house bees
Ein verbessertes verfahren zur isolierung und quantitativen bestimmung von vincaleukoblastin aus intakten pflanzen und gewebekulturen von catharanthus roseus g. don. / An im proved method of isolation and titative determination of vincaleucoblastine from intact plants and tissue cultures of catharanthus roseus g. don.
Authors: Hofmann W. , Kubeczka K.-H. , Czygan Franz-C. 
Published: August 2018

Improved methods of extracting vincaleucoblastin from leaves and tissue cultures of Catharanthus
roseus and of the quantitative determination of this dimeric indole-alkaloid by reflectance densitometry of TLC-plates have been established. Approximately 0.05% VLB were found in the leaves and, using high-performance-thin-layer-chromatography, 0.00013% VLB in callus cultures (not in suspension cultures!) derived from this plant
Mechanisms of Inhibition by Mevinolin (MK 803) of Microsome- Bound Radish and of Partially Purified Yeast HMG-CoA Reductase (E C .l.1.1.34)
Authors: Bach Th. J. , Lichtenthaler H. K. 
Published: August 2018

1) In kinetic studies, mevinolin proved to be a highly specific inhibitor of partially purified yeast HMG-CoA reductase (Ki = 3.5 nᴍ towards HMG-CoA) and of microsomal HMG-CoA reductase from etiolated radish seedlings (Ki = 2.2 nᴍ). At low concentrations of NADPH, the inhibitor counteracts the sigmoidal response of plant HMG-CoA reductase activity towards the cosubstrate. At higher concentrations of NADPH, the inhibition pattern is of non-competitive type.
2) Our results are extensively compared with that obtained by the use of animal tissue and yeast as an enzyme source in order to discuss model systems probably valid to evaluate properties and regulation of plant as well as yeast HMG-CoA reductase
New Cembranoids from Tobacco, II
Authors: Bylov Anne-Marie , Brümmer Ursula , Hass Werner , Seehofer Friedlieb , Heemann Volker 
Published: August 2018

The methylethers 4-O,8-O-dimethyl-(1S, 2E, 4R, 6E, 8S, 11E)-2,6,11-cembratriene-4,8-diol (9), 4-O-methyl-(1S, 2E, 4R, 7E, 11E)-2,7,11-cembratriene-4,6-diol (4) und 4-O,6-O-methyl-(1S, 2E, 4R, 7E, 11E)-2,7,11-cembratriene-4,6-diol (8) were identified as new natural products from tobacco. They were isolated from processed tobacco as well as from leaf surface gum of fresh tobacco.
The spectral data of all six methylethers of (1S, 2E, 4S, 6R, 7E, 11E)- and (1S, 2E, 4R, 6R, 7E, 11E)-2,7,11-cembratrienen-4,6-diol are given.
Biosynthesis of Cyanogenic Glycosides in Butterflies and Moths: Incorporation of Valine and Isoleucine into Linamarin and Lotaustralin by Zygaena and Heliconius Species (Lepidoptera)
Authors: Wray V. , Davis R. H. , Nahrstedt A. 
Published: August 2018

Abstract
C -13 NMR data for linamarin and lotaustralin, obtained after feeding of either Zygaena Jilipendulae or Heliconius melpomone (Lepidoptera) with C-13 enriched valine and isoleucine respectively, indicate that intact units of amino acid with loss of the carboxyl group are incorporated during the biosynthesis of these cyanogenic glycosides.
Hydrogen Bond Indices and Tertiary Structure of Yeast tRNAPhe
Authors: Giambiagi M. S. de , Giambiagi M. , Esquivel D. M. S. 
Published: August 2018

Abstract
The rigidity and stability of the tertiary structure of yeast tRNAPhe is related to a bond index obtained in an IEHT (iterative extended Hückel theory) calculation. The index permits a quantitative estimate of the electron density along the hydrogen bond, having thus an appealing physical meaning. The results indicate that Hoogsteen-type bonds have, as expected, greater electronic population than Watson-Crick type ones. Other non-Watson-Crick pairs, the wobble pair and G15-C48, exhibit high values of the index for the NH ... O bond. In the triples, the electron density of the hydrogen bridges does not weaken (compared with the one of the pairs involved). Contour density maps are shown and dipolar moments of pairs and triples are qualitatively discussed.
Decreased Production of RNA-Streptolysin S in Streptococci Devoid of Extracellular RNase Activity
Authors: Taketo Akira , Taketo Yoriko 
Published: August 2018

Abstract
In cultures of certain streptococcal strains, RNA added as a carrier for streptolysin S (SLS) was hardly degraded, owing to deficiency of extracellular RNase activity. Production of RNA-SLS into culture supernatant was markedly reduced in the RNase-deficient streptococci. Even in these RNase-less strains, guanylic-acid rich oligonucleotides, polyG or trypan blue effectively induced SLS production, as in RNase-positive cells. These results demonstrate involvement of the streptococcal nuclease in manifestation of SLS-inducing effect of exogenous RNA. Additional data indicated that cellular growth was promoted by supplementation of RNA, in the nuclease-producing streptococci.
Conformational Study of Catecholamines in Solution
Authors: Šolmajer P. 
Published: August 2018

Abstract
Conformations of noradrenaline, dopamine and ephedrine have been studied in aqueous solutions using high resolution PMR spectroscopy. We found that for dopamine the mole fraction of trans rotamer is increased if pH is changed from acidic to basic while for nor­adrenaline and ephedrine the opposite trend is observed: gauche rotamer forms of the side chain become more populated. These changes are discussed in relation to the role of the benzylic hydroxyl group for conformation and/or binding to a receptor site in the biophase.
Notizen: The Effect of Alcohol Oxidase on the Ascorbic Acid-Erythrocyte Interaction: ESR Investigations
Authors: Lohmann W. , Schreiber J. , Holz D. 
Published: August 2018

Abstract
Addition of alcohol oxidase to erythrocytes treated with ascorbic acid reverses the vitamin C effect, as expressed by the appearance of the semidehydroascorbate signal, and the increase in spin concentration. The original erythrocyte electron spin resonance (ESR) signal is, how ever, never restored completely, as it is in the case if ascorbate oxidase is used. Additional interaction between the enzyme alcohol oxidase and haemoglobin iron must occur, since both o f the iron ESR signals at g = 4.3 and g = 6 disappear and the erythrocyte ESR spectrum at g ≈ 2 is changed characteristically. The spin concentration of the latter spectrum increases again above a certain concentration of alcohol oxidase.
Notizen: Effect of Ecdysterone on Food Intake of Locusta migratoria Hoppers
Authors: Rao P. J. , Rembold H. 
Published: August 2018

Abstract
Ecdysterone administration at physiological concentra­tions (35 μg /hopper) on alternate days decreased the live weight gain and faecal production in both sexes of 5th instar nymphs of Locusta migratoria. All treated hoppers at this dose failed to moult. No such effects were observed when the hoppers were administered with half of the dose.
07g and D6a: Two Flavone Glycosylating Genes in Silene, which are Only Expressed in Cotyledons and Rosette Leaves
Authors: Steyns J. M. , Mastenbroek O. , Nigtevecht G. van , Brederode J. van 
Published: August 2018

Two further loci can be added to the three already known (g, gl and fg) in Silene controlling the 7-O and 2″-O-glycosylation of the C-glycosylflavone isovitexin (6-C-glucosylapigenin). These loci, O7g for the 7-O-galactosylation and D6a for the 2″-O-arabinosylation, appear only to be expressed in cotyledons and rosette leaves and control the biosynthesis of isovitexin 7-O- galactoside and isovitexin 7-O-galactose 2″-O-arabinoside in these parts of plants in which the recessive alleles of the loci g, gl and fg are homozygous (Steyns et al. [9]).
The possibility that locus g, whose dominant alleles gG and gX control the 7-O-glucosylation and the 7-O-xylosylation of isovitexin respectively, controls the synthesis of isovitexin-7-O- galactoside was excluded by demonstrating the presence of isovitexin-7-O-galactoside and the 7-O-galactosyltransferase catalyzing its biosynthesis in addition to isovitexin-7-O-glucoside and the 7-O-glucosyltransferase in cotyledons of gGgG seedlings.
The synthesis of the 2″-O-arabinoside is neither controlled by locus gl, whose dominant alleles glR and glA control the 2″-O-rhamnosylation and 2″-O-arabinosylation of isovitexin respectively, nor by locus fg, whose dominant allele Fg controls the biosynthesis of isovitexin 2″-O-glucoside. This was shown by the presence of isovitexin-7-O-galactose 2″-O-arabinoside and the 2″-O-arabinosyltransferase catalyzing the synthesis of the 2″-O-arabinoside in addition to isovitexin-7-O-galactose 2″-O-rhamnoside in cotyledons of glRglR seedlings and by the presence of isovitexin-7-O-galactose 2″-O-arabinoside and the 2″-O-arabinosyltransferase in addition to isovitexin-7-O-galactose 2″-O-glucoside and the 2″-O-glucosyltransferase in cotyledons of Fg Fg seedlings.
HPLC Analysis of Alkaloids in Extracts of Callus Cultures of Cinchona Species
Authors: Verpoorte Robert , Mulder-Krieger Thea , Wijnsma Rommert , Verzijl Jacques M. , Svendsen Anders Baerheim 
Published: August 2018

Abstract
The quantitative analysis of the alkaloids in Cinchona tissue cultures by means of a reversed-phase ion pair HPLC method is reported.
The Influence of Amino Acid Ligands and Vitamin C on the Reduction Potential of Fe(III): Polarographie and Electron Spin Resonance Investigations
Authors: Kiefer Berthold , Sapper Helmut , Lohmann Wolfgang 
Published: August 2018

Abstract
The pH dependence of Fe(III)-amino acid complexes has been studied polarographically and by means of ESR spectroscopy.
It could be shown that, at least, two complexes exist: one with a low molecular weight, ESR detectable at acid pH. and one with a high molecular w eight at alkaline pH, ESR non detectable. The half wave potential of Fe (III) is lowered by amino acid ligands.
The redox interaction of the Fe(III)-amino acid complexes with vitamin C results in a decrease of the ascorbyl radical concentration. Ascorbic acid also forms a complex with Fe(III) as in­dicated by a polarographic half wave potential near -0.55 V vs. S.C.E. at pH 7.
Legume Root Response to Symbiotic Infection. Enzymes of the Peribacteroid Space
Authors: Mellor Robert B. , Mörschel Erhard , Werner Dietrich 
Published: August 2018

Abstract
Three of the major soluble partitioned pools in the symbiotic cell, namely the host cell cytoplasm, the cytoplasm of the bacterial symbiont and the space between the two partners (the peribacteroid space) were assayed for selected enzymes. Whilst alanine dehydrogenase was found almost totally in the bacterial cell cytoplasm, other enzymes were more widely spread. Amongst these a-mannosidase, previously described as a vacuolar marker enzyme in eukaryotes, was found largely in the peribacteroid space.
These results are discussed in relation to models of peribacteroid membrane biogenesis.
Conductivity of Normal and Pathological Human Erythrocytes (Homozygous β-Thalassemia) at Radiowave Frequencies
Authors: Ballario C. , Bonincontro A. , Cametti C. , Rosi A. , Sportelli L. 
Published: August 2018

Abstract
The conductivity of normal and homozygous β-thalassemic erythrocyte suspensions has been measured over the frequency range from 5 KHz to 100 MHz in the temperature interval from 5 to 45 °C.
The electrical parameters of the membrane, i.e., the capacitance CM and the conductance GM per unit surface have been calculated from an expression given by Hanai for the conductivity of a suspension of ellipsoidal particles covered with a shell.
Some interesting differences between the normal and pathological state are evidentiated.
ESR Investigations on Lyophilized Blood: Mixtures with Ascorbic Acid
Authors: Neubacher Harald 
Published: August 2018

Abstract
The main contribution to ESR spectra of lyophilized tissues of plant or animal origin usually is given by an anisotropic singlet, which is known to be caused at least in the majority of cases by the adsorption of an ascorbyl radical. Model systems have been in vestigated in order to discuss experimental parameters, which in fluence these spectra qualitatively and quantitatively.
Preparation of an Affinity Chromatographic System for the Separation of ADP Binding Proteins
Authors: Bieber Elke , Woenckhaus Christoph , Pauli Harald 
Published: August 2018

Abstract
[4-(3-Bromoacetylpyridinio)-butyl]adenosine pyrophosphate as a structural analog of NAD+ reacts covalently with the sulfhydryl groups of thiopropyl agarose. 10-20 μmol can be bound to 1 ml gel. Stabilization of the insoluble coenzym e is attained by treatment with sodium boro hydride (NaBH4). This complex when applied to column chromatography, allow s the separation of various dehydrogenases as a result of their different complex stability coefficients. Alcohol dehydrogenase from liver, lactate dehydrogenase, and adenylate kinase, which all bind to the ADP-analog residues of the gel matrix, can thus be separated by different salt gradients. Alcohol dehydrogenase from yeast, however, does not form a complex and can easily be eluted from the column with phosphate buffer. Glyceraldehyde-3 phosphate and aldehyde dehydrogenases can be eluted by the addition of NAD+ or NADH to the buffer. The uncharged 1,4-dihydropyridin ring of the reduced coenzyme produces a more stable complex with the dehydrogenases than the oxidized form.
A Simple Method to Prepare Affinity Resins on Cellulose Basis
Authors: Eisele Karl , Costa Fernando Dias , Pascual Carlos , Ofenloch-Hähnle Beatus 
Published: August 2018

Abstract
Affinity resins with different spacer arms were synthesized analogues to the solid phase peptide synthesis using aminoethyl cellulose or carboxymethyl cellulose as matrix. The spacer arms could be varied in length and rigidity. Especially spacer arms consisting of poly am ino acids can be synthesized with a defined amount of amino acid residues specifically in the low molecular weight ranges. The method is also applicable to other matrices w hich are not susceptible to 1 ɴ HCl in glacial acetic acid, trethylamine, methylene chloride and dimethylformamide.
The synthesis of affinity resins with different spacer arms for the purification of androgen receptors is described as an example of the method.
Isolation of the Adducts of Platinum Complexes and Nucleic Acid Bases on the Dowex 50 W Column
Authors: Olinski Ryszard , Walter Zofia 
Published: August 2018

Abstract
The method presented here enables the isolation of three monofunctional adducts. These are: platination of cytosine, adenine and guanosine. The three detected bifunctional complexes were: guanine N7 to N7, adenine N7 to N7 and adenine N7 to N1. A mixed bifunctional complex of guanine and adenosine and the product of polymerization of three adenines and two moieties of cis DDP were also detected.
In the peak eluted separately from the guanine standard, no Pt was detected. The sample eluted in this peak had UV spectrum different from the standard and may represent the degraded product of guanine and polymerized Pt.
Structural Studies on the Galactan from the Albumin Gland of Achatina fulica
Authors: Holst Otto , Mayer Hubert , Okotore Rufus O. , König Wilfried A. 
Published: August 2018

Abstract
The structure of the galactan isolated from the album in gland of Achatina fulica (African giant snail) was investigated by methylation analyses. The molecule is highly branched. The linkages of the exclusively present D-galactose are 1→3 and /or 1→6. From lectin binding studies it was learnt that the 1→3 linkages possess β-configuration. The anomeric configuration of the 1→6 linkage is unknown. A tentative structure of the galactan is proposed.
High Energy Radiation-Induced Crosslinking of Histone Octamer Complexes
Authors: Deeg K.-J. , Katsikas L. , Schnabel W. 
Published: August 2018

Abstract
Calf thymus histone octamer complexes were irradiated in the native state in N2O-saturated dilute aqueous solution (0.5 g/l, pH 9, [NaClO4] = 1-4 mol/1) with 50 or 100 ns pulses of 16 MeV electrons or 60Co-γ-rays. Tim e resolved light scattering measurem ents and optical ab­sorption measurements yielded the following: the octamers underwent a volume contraction due to intra-complex-crosslinking induced by the attack of OH-radicals. Crosslinking proceeded to a certain extent via 2 ,2′-biphenol coupling as inferred from product analyses.
Effects of Membrane-Acting Drugs and Aerobiosis on Production of Streptolysin S and Nuclease in Hemolytic Streptococci
Authors: Taketo Akira , Taketo Yoriko 
Published: August 2018

Abstract
Yield of streptolysin S (SLS) in streptococcal culture was considerably reduced by procaine, dibucaine, atropine or chlorpromazine at concentrations which scarecely affected production of an extracellular nuclease as well as the bacterial growth. Cerulenin was also inhibitory to SLS formation, but its effect was more pronounced on the nuclease production. By aerobiosis, amount of SLS produced into culture supernatant was increased significantly, whereas yield of the nuclease was rather unaffected.
Impaired Diffusion Coupling-Source of Arrhythmia in Cell Systems
Authors: Schreiber Igor , Kubíček Milan , Marek Miloš 
Published: August 2018

Abstract
A detailed analytical and numerical analysis of a simple reaction-diffusion model of the source of non-homogeneities and arrhythmias in an originally homogeneous reaction system is presented. Solution, bifurcation and evolution diagrams are used to describe the behaviour of the model. It is shown that under certain conditions steady and/or oscillatory nonhomogeneous states are the only stable solutions of the model. These phenomena are essentially not dependent on a particular reaction kinetics. A possible relevance to some biological situations is discussed.