bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrastructure of Differently Pigmented Synechococcus Cells
Authors: Döhler Günter , Barckhausen Ralf , Ruppel Manfred 
Published: August 2018

Abstract
Synechococcus (Anacystis nidulans, strain L 1402-1) were grown at + 37 °C in an atmosphere of 0.04 vol.% CO2 using different light conditions. Changing the culture conditions caused alterations in pigment ratios and ultrastructure of Synechococcus. In comparison to the low white and red light grown cells under strong white light the number of thylakoids decreased and an accumulation of storage carbohydrates could be observed. The number of the polyhedral bodies also varied with culture conditions. The results are discussed with reference to the pigment composition and the function of the polyhedral bodies.
On the Biosynthesis of C30 Carotenoic Acid Glucosyl Esters in Pseudomonas rhodos. Analysis of car-Mutants
Authors: Kleinig Hans , Schmitt Rüdiger 
Published: August 2018

Abstract
car-Mutants of Pseudomonas rhodos were isolated and classified into four types according to their blockage in the biosynthetic pathway. A biosynthetic scheme could be established. Three new structures could be identified (4,4'-diapocarotene-4,4'-dial, 4,4'-diapocarotene-4-al-4'-oic acid, glucosyl-4,4'-diapocarotene-4-oate).
Kinetics of Proton-Hydroxyl Transport across Lecithin Vesicle Membranes as Measured with a Lipoid pH-Indicator
Authors: Pohl W. G. 
Published: August 2018

When unilamellar vesicles are prepared in the presence of 3-Palmitoyl-7-oxy-coumarin (abbreviation 3P-UBF) this lipoid pH-Indicator is anchored by its fatty acid chain to the membrane and can be used to measure pH-changes at the outer and inner membrane surface (ranging from pH 5 to pH 9.5). By rapidly-changing the pH of the outer aqueous phase a pH- gradient is set up across the vesicle membrane. The rate of the subsequent H+ or OH- influx into the vesicles can be measured as a change of the 3P-UBF absorbance at 424 nm. This was done with a stopped-flow-spectrophotometer at temperatures between 10 °C and 50 °C.
Suspensions of vesicles prepared from egg-lecithin or ʟ-dipalmitoyl-lecithin were investigated in buffered salt solutions. The influence of Na+, K+, Cl-, SO4
2- and valinomycin on the rate of absorbance changes was studied at different temperatures.
It was found that the rate of the pH-equilibration between the aqueous phase outside and inside the vesicles depends on the direction of the pH-gradient. This new result together with a high H+/OH- permeability of vesicle membranes found in recent studies from other laboratories and confirmed by this investigation is interpreted to indicate a higher permeability of the vesicle membrane to OH--ions compared to H+-ions. (Calculated values are: POH = 1.4 × 10-4cm/s at pH 9 and PH = 8.3 × 10-7 cm/s at pH 5 and 20 °C.) All data described in the literature in detail agree with this suggestion but a pH-dependence of POH and PH cannot be excluded.
Proteinase-Inhibitors in Albumin Glands of Achatina fulica
Authors: Okotore R. O. , Uhlenbruck G. 
Published: August 2018

Abstract
Three different polyvalent proteinase-inhibitors have been detected in the albumin gland of the snail, Achatina fulica and identified by means of fibrin-agar immunelectrophoresis. The inhibitory activity of these substances against several proteinases from different sources was investigated.
State of Iron in the Archaebacterium Methanosarcina barkeri Grown on Different Carbon Sources as Studied by Mössbauer Spectroscopy
Authors: Scherer P. , Sauer Ch. 
Published: August 2018

Abstract
Cells of the archaebacterium Methanosarcina barkeri were grown strictly anaerobic in defined media. 57Fe-Mössbauer Spectroscopy of methanol grown cells oxidized in the presence of air demonstrated only the state of Fe3+ whereas active cells under reducing conditions offered spectra of two additional iron sites in the Fe2+ state. Furthermore the 57Fe hyperfine interaction data at different temperatures gave evidence that cells cultivated with methanol or acetate as substrate contained ferredoxin like compounds.
Rotating-Field-Induced Rotation and Measurement of the Membrane Capacitance of Single Mesophyll Cells of Avena sativa
Authors: Arnold W. M. , Zimmermann U. 
Published: August 2018

Rotation of single cells (mesophyll protoplasts of Avena sativa) induced by a planar, homogeneous rotating field has been observed at a frequency of 20-40 kHz (conductivity of the external mannitol solution 6x 10-5 Ω-1 cm-1). This variation in optimum frequency is largely due to an inverse dependence on cell radius. Rotation direction is opposite to that of the field, and can be reversed at will by reversing the field. The maximum speed of cell spinning was a few cycles per second (and thus always much slower than that of the field) and was proportional to the square of the amplitude of the field.
The rotation of a single cell in a rotating field is expected on the basis of the dipole-dipole theory developed by Holzapfel et al., (J. Membrane Biol. 67, 1-14 (1982)), for multi-cell rotation. Measurements of the dependence of optimum applied field frequency on medium conductivity indicate that the dipole is generated by interfacial (Maxwell-Wagner) polarization. The required frequency is a linear function of the conductivity of the external solution. This relationship is used to derive a value for the specific membrane capacitance. Further applications of this technique for cell and membrane research are discussed.
Evaluation of (Z)-5-Decen-1-ol as an Attractant for Male Larch Casebearer Moths, Coleophora laricella
Authors: Priesner Emst , Altenkirch Wolfgang , Baltensweiler Werner , Bogenschütz Hermann 
Published: August 2018

Electroantennogram studies on C. laricella males demonstrated that the title compound, (Z)-5-decen-l-ol (Z5-10:OH), elicited the highest response among a series of straight-chain, C10 to C16 alcohols, acetates and aldehydes tested. From selective adaptation of antennal responses it was concluded that an additional type of receptor cell responded to the corresponding acetate, Z5-10: Ac.
Field attraction experiments were carried out by using delta-type sticky traps and rubber-cap odour dispensers. The main test sites were located in the Swiss Alps, Black Forest and northwestern Germany, and included both European and Japanese larch stands, having different degrees of C. laricella infestations. At all test sites pure Z5-10:OH proved to be highly attractive to native male moths over a range of different lure doses, with a progressive increase of captures towards the higher (100 μg, 1000 μg) attractant sources. However, following captures of 200-400 moths/trap the “retaining capacity” of the sticky surfaces of the traps were found to decline markedly; in tests of the higher attractant doses at sites of higher moth densities, this “saturation effect” frequently occurred within a few hrs of trap exposure, thus demonstrating the limitation in the use of sticky traps for monitoring economically-relevant C. laricella populations. Trap placement studies (using the standard attractant of 100 μg Z5-10:OH) showed substantial captures only for those traps placed on green branches within the host crowns.
The acetate analogue (Z5-10:Ac) strongly reduced male responses to the attractant alcohol (Z5-10:OH) when evaporated from the same trap, admixtures of 0.3% and 1% of this acetate reducing captures by 90% and almost 100% respectively. Possible functions of this inhibitor are briefly considered. No evidence for attractant synergism was obtained during the present study. The results suggest that Z 5-10: OH is a major constituent of the yet unidentified C. laricella sex pheromone.
Structure Investigations of Agonists of the Natural Neurotransmitter Acetylcholine, III [1] X-Ray Structure Analysis of (2-Ethoxyethyl)trimethyl- ammonium Chloride
Authors: Gieren Alfred , Kokkinidis Michail 
Published: August 2018

Abstract
To elucidate the structure-activity correlations we have performed an X-ray structure analysis of the title compound (1), which is a muscarinic agonist of the natural neurotransmitter acetyl­ choline. 1 crystallizes in the monoclinic space group P 21/n with 2 molecules per asymmetric unit. Lattice parameters are: a = 10.375(6), b = 12.468(5), c = 15.274(17) Å; β= 95.32(7)°. The structure was solved by direct methods and refined to an R-value of 0.14 for 1828 observed reflections. Both cations in the asymmetric unit are disordered. In the crystal structure at least four conformations of the cation occur, indicating a pronounced conformational flexibility of the neurotransmitter cation. The anions are arranged stereospecifically with respect to the quaternary trimethylammonio methyl group. The geometry of triangles which are defined by a nitrogen of the quaternary ammonium group and an ether oxygen on one hand and an anion occupying a specific type of tetrahedral faces of a (CH3)3N+-CH2 group on the other hand, is characteristic for muscarinic agonists if they contain an ether or ester oxygen in the analogous position to the ester oxygen of acetylcholine.
Tl+-Ions: Comparison of the Effects on the Slow Inward Current and Contractility of Ventricular Tissues
Authors: Wiemer J. , Ziskoven R. , Achenbach C. 
Published: August 2018

To conclude our investigation of thallium effects on cardiac tissues, we studied the slow inward current of sheep cardiac Purkinje fibres exposed to 10-7 to 10-5 ᴍ Tl+ for extended periods of up to 80 min. Our previous results had suggested a possible involvement of the slow inward current during thallium intoxication: a) the modification of contractility staircases observed during thallium exposure, b) action potential recordings of ventricular muscle, c) changes in spontaneous beating in sino-atrial preparations. The thallium levels chosen were between those yielding strong positive inotropic transients and those producing a marked long­term decay of contraction force.
The slow inward current was measured using a conventional two-microelectrode-technique and the standard voltage clamp protocol for this current system. The experimental work was restricted to the determination of d∞, the kinetics of activation of the slow inward current and of īsi, the current voltage relation of the current system. This was necessary since the effects of thallium were known to be short-lived and therefore frequent repeat runs of the voltage clamp program had to be performed in order to obtain the time courses of possible transient changes.
The results showed that the slow inward current was first increased and then declined at the low concentration of 10-7 ᴍ Tl+. At 10-5 m Tl+ the initial increase was smaller, whereas the decay of the slow inward current proceeded to lower values. Comparison with contractility measure­ments at the same concentrations of thallium showed a distinct parallelism between changes of the slow inward current and myocardial contractility. Despite this apparent relationship, we do not conclude that the contractile events are primarily a result of changes of the slow inward current, since thallium does not seem to specifically alter the parameters of the slow inward current at the membrane level.
Composition of Epicuticular Waxes from Fruits of Jojoba (Simmondsia chinensis [Link] Schneider)
Authors: Gülz Paul-Gerhard 
Published: August 2018

Abstract
Epicuticular waxes were extracted with hexane from dry Jojoba pericarp and seed. These cuticular waxes consisted of hydrocarbons, wax esters, free acids, free alcohols and sterols; additionally aldehydes were found in the wax obtained from seed coats. The hydrocarbon fraction contained a homologous series of n-alkanes and branched alkanes but no alkenes. The composition of the wax esters of the cuticular wax was similar to that of the cotyledons. The esters are composed of monounsaturated long chain acids and alcohols.
The Sex Pheromone of the Silver Y Moth Chrysodeixis eriosoma (Doubleday) in New Zealand
Authors: Benn M. H. , Galbreath R. A. , Holt V. A. , Young H. , Down G. , Priesner E. 
Published: August 2018

Abstract
An investigation of the sex pheromone of the New Zealand Silver Y Moth Chrysodeixis erio­soma (Doubleday), formerly described as Plusia chalcites (Esper) resulted in the identification of the major active components as 7Z-and 9Z-dodecenyl acetates, in approx. 97:3 ratio. This blend was attractive to C. eriosoma males in the field and in a laboratory flight tunnel. 5Z-D odecenyl acetate and 7Z-dodecenyl alcohol inhibited this response in the field. C. eriosoma was also attract­ed to the 5:1 blend of 7Z-dodecenyl acetate and 9Z-tetradecenyl acetate reported as the phero­mone of Chrysodeixis (Plusia) chalcites in the western Palaearctic. Specialist receptor cells for all 5 compounds mentioned were found in male antennal sensilla in both species.
Functional Regeneration of the Visual System in Teleosts. Comparative Investigations after Optic Nerve Crush and Damage of the Retina
Authors: Kästner Roland , Wolburg Hartwig 
Published: August 2018

Abstract
Goldfish and carp are shown to be capable of functional reconstitution of the visual system, although their neural retina except of the marginal growth zone at the ora serrata was completely destroyed by injection of the Na-K-ATPase inhibitor ouabain. This was demonstrated by the observation of the recovery of the optokinetic nystagmus after dam age of the retina. Recovery of vision coincides well with the morphological reconstitution of the visual system. The regenerated axons within the optic nerve are still unmyelinated at the moment of visual recovery, whereas some fibers within the stratum opticum pars profunda of the corresponding optic tectum are already myelinated. The recovery of vision after regeneration of the retina was com pared with the recovery of vision after crush of the optic nerve. The range of time needed for visual recovery was smaller and better reproducible after crush than after dam age o f the retina.
Adenine Phosphoribosyltransferase Activity in Mitochondria of Catharanthus roseus Cells
Authors: Hirose Fumiko , Ashihara Hiroshi 
Published: August 2018

Abstract
Subcellular localization of adenine phosphoribosyltrans­ferase was examined in Catharanthus roseus cells. At least 13% of the activity was observed in the particulate fraction with the rest observed in the cytosol. Both differential and Percoll density gradient centrifugation indicated that particulate adenine phosphoribosyltransferase was predominantly located in the mitochondria.
Ein neues Catechinglykosid aus Polypodium vulgare / A New Catechin Glycoside from Polypodium vulgare
Authors: Karl Christian , Müller Gerhard , Pedersen Peter Alsted 
Published: August 2018

Abstract
From acetone extracts of fresh aerial parts o f Polypodium vulgare L. 9 phenolic compounds were isolated. Two of them, catechin 7-O-ᴅ-apioside and kaempferol 3-O-(4 or 5-rhamnosyl) arabinoside, were found for the first time in nature. Furthermore it was shown that polydine is catechin, 7-O-α-ʟ-arabinofuranoside. The other components were rutin, hyperin, kaempferol- 3-O-glucoside and -arabinoside-7-O-rhamnoside and the C-glycosides schaftoside and isoschaftoside.
Phenazine and Phenoxazinone Biosynthesis in Brevibacterium iodinum
Authors: Herbert R. B. , Mann J. , Römer A. 
Published: August 2018

Abstract
The source of nitrogen in the phenazine, iodinin 5, and in 2-aminophenoxazinone 7 in Brevi­ bacterium iodinum cultures is shown to be primarily from the amide nitrogen of glutamine in experiments with (S)-[CO15NH2]glutamine, [15N]ammonium sulphate, and (S)-[15N]glutamic acid. The biosynthesis of 5 and 7 is closely related; biosynthesis o f 7 like that o f 5 diverts from the shikimic acid pathway at a stage prior to anthranilic acid 8.
The Site of Indole-3-acetic Acid Synthesis in Mesophyll Cells of Spinacia oleracea
Authors: Heilmann B. , Hartung W. , Gimmler H. 
Published: August 2018

Abstract
Using [14C]tryptophan as a precursor, the intracellular localization of indole-3-acetic acid biosynthesis in spinach mesophyll cells was investigated. Chloroplasts as well as extraplastidic compartments were able to transform tryptophan into indole-3-acetic acid.
The cofactor requirement of plastidic and extraplastidic indole-3-acetic acid synthesis is shown.
Light and abscisic acid treatment inhibited preparations.
CO2 Fixation in Anabaena cylindrica
Authors: Döhler Günter 
Published: August 2018

Abstract
The cyanobacterium Anabaena cylindrica grown in a nitrogen -free medium at + 25 °C was used for short-term 14C-kinetics experiments under different conditions. During the dark/light transients the initial fixation products were mainly sugar monophosphates and 3-phosphoglyceric acid (Calvin cycle intermediates), aspartate (10% of total radioactivity) and glycine/serine. Io­ doacetamide (0.01 м) caused an inhibition o f photosynthetic 14CO2 fixation and a 14C-in corpor­ation into aspartate, glutamate and 3-phosphoglyceric acid only. During dark 14CO2 assimilation labelling of these products could be measured, too. In a nitrogen atmosphere (N2 + 0.04 vol. % CO2) a strong labelling of sugar monophosphates mainly at the beginning o f photosynthetic period could be observed. In an oxygen atmosphere (100% O2) an enhanced label of aspartate and glycerate and a decreased radioactivity in sugar monophosphates were found. Our results were discussed with reference to the operating of a phosphoenolpyruvate carboxylation reaction be­ sides the Calvin cycle and to the glycolate metabolism.
Digitonin Precipitable Sterols Inducing the Aggregation of Prolamellar Body-Like Structures from Completely Dissolved PLB Components
Authors: Nisius A. , Müller M. , Ruppel G. 
Published: August 2018

Abstract
Completely dissolved lipids of a prolamellar body/primary thylakoid (PLB/PT) fraction from etiolated Avena sativa plastids were reaggregated in vitro. The analysis of the originating tubular structures showed a qualitative identity in their lipid content with that of the native PLB/PT fraction. Reaggregation experiments also showed that not all lipids constituting the PLB are necessary to build up the tubular structures. Only avenacosids A and B together with 3-β-hydroxy-sterols are the obligatory structural components.
Absorption and Picosecond Fluorescence Characteristics of Chlorophyll Vesicles as a Function o f Temperature
Authors: Brody Seymour Steven 
Published: August 2018

Abstract
With chlorophyll a-dipalmitoylphosphatidylcholine-liposomes, the absorption increases at 706 and 450 nm, and decreases at 660 and 420 nm, as the temperature is lowered. As the temperature is increased opposite changes are observed. A lipid phase change occurs at 34°. The pigment to lipid ratio is 1 to 5 in the liposome.
With chlorophyll a-soy bean lecithin-liposomes the absorption increases at 706, 680 and 440 nm, and decreases at 650 and 430 nm, as the temperature is lowered. As the temperature is increased, opposite changes are observed. A lipid phase change occurs at 26-27 °C. The pigment to lipid ratio is 1 to 13. The spectral change at 706 nm is identified with aggregated chlorophyll. The concentration of chlorophyll aggregate increases as the temperature is lowered, and decreases as the temperature is raised.
Fluorescence decay from chlorophyll a-soy bean lecithin-liposomes is biphasic. The lifetimes of freshly prepared liposomes are 121 ± 4 ps and 1400 ± 200 ps. The relative contribution of the fast and slow fluorescence components are modified by temperature. Heating results in an increase in both lifetimes, and an increase in fluorescence from the long lived component. These changes are interpreted as resulting from a decrease in energy transfer and concentration quenching. The origin of the biphasic fluorescence and spectral transformations in liposomes, and the possible relation between in vitro and in vivo picosecond fluorescence is discussed.
New Flavonoids from the Farina of Pityrogramma Species
Authors: Hitz Christiane , Mann Karin , Wollenweber Eckhard 
Published: August 2018

Abstract
2′,6′,4-OH, 4′-OMe-chalcone (neosakuranetin) and 2′,6′,4-OH, 4′-OMe-dihydrochalcone (asebogenin) were found as major constituents of the frond exudate on one in­ dividual plant of Pityrogramma calomelanos. Galangin-5,7-dimethyl ether was isolated from the farina on fronds of a certain population of Pityrogramma triangularis as a novel natural flavonol.
Struktur von Echinacosid / Structure of Echinacoside
Authors: Becker Hans , Hsieh Wei Ch. , Wylde Renée , Laffite Colette , Andary Claude 
Published: August 2018

Abstract
The structure of echinacoside, isolated from Echinacea angustifolia D.C. (Asteraceae) roots has been determided by 1H-NMR-and 13C-NMR-spectra to be β-(3′,4′-dihydroxyphenyl)-ethyl-O-α-ʟ-rhamnopyranosyl (1 → 3)-O-β-ᴅ-[β-ᴅ-glucopyranosyl (1 → 6)]-(4-O-caffeoyl)-glucopyranoside (cf. Fig. 1).
Diurnal Fluctuation of Quinolizidine Alkaloid Accumulation in Legume Plants and Photomixotrophic Cell Suspension Cultures
Authors: Wink Michael , Hartmann Thomas 
Published: August 2018

Abstract
Fluctuations of quinolizidine alkaloid content in leaflets of Lupinus polyphyllus, L. hartwegii, Baptisia australis, and Sarothamnus scoparius were studied over a 36 h period. The alkaloid contents reached their maximum at noon or early afternoon, and their minimum during the night. The amplitudes of diurnal variations in alkaloid levels lay within a range of 60 to 470% of the early morning contents of alkaloids (= 100%) in leaves. In photomixotrophic cell suspension cultures of L. polyphyllus and S. scoparius cultured under day-night regime, a similar increase of the alkaloid levels was observed within 5 to 8 h after onset of illumination. A subsequent excretion of the alkaloids produced, which also followed a diurnal rhythm, was found. S. scoparius cells excreted lupanine, L. polyphyllus cells 13-cinnamoyloxylupanine. From the cell culture and plant experiments it can be assumed that the alkaloids which are formed during illumination are translocated to some degree afterwards. In cell suspension cultures the alkaloids are subjected to rapid and rhythmic turnover. Exogenous alkaloids, fed to the cultures, are taken up by the cells and disappear usually within the first 72 h. A possible mechanism for a light-mediated regulation of quinolizidine alkaloid biosynthesis which was found to be localized in leaf chloroplast, is discussed.
Purification and Properties of Glucosaminephosphate Isomerase of Proteus mirabilis
Authors: Cifuentes Blanca , Vicente C. 
Published: August 2018

Abstract
A glucosamine-P isomerase has been identified in Proteus mirabilis. The 113-fold purified enzyme exhibits a pH optimum of 7.5 with a secondary maximum at 8.5 and a temperature optimum at 37 °C. The apparent Km was 13.3 mᴍ for fructose-6-P and 18.8 mᴍ for ʟ-glutamine. Molecular weight of the enzyme has been estimated as 120000 and the protein can be dissociated in four subunits by SDS-polyacrylamide electrophoresis.
Antiviral Activity of 2-(α-Hydroxybenzyl)-Benzimidazole and other 2-Substituted Benzimidazoles against TMV in Tomato Leaf Discs
Authors: Cassells Alan C. , Cocker Frances M. 
Published: August 2018

Abstract
2-(α-hydroxybenzyl)-, 2-benzyl-, 2-phenyl-, 2-methyl-and 2-hydroxymethyl-benzimidazoles were screened for antiviral activity against TMV in tomato leaf discs, for cytokinin activity in the amaranthus betacyanin bioassay and the soya bean callus bioassay and for antagonism in the latter bioassay. None of the test compounds showed either cytokinin activity or antagonism. 2-(α-hydroxybenzyl)-benzimidazole at 23.3 μᴍ inhibited infectious virus production by 100% and no virus antigen was detectable. None of the other compounds showed similar antiviral activity. The realationship between the substituent at the 2-position and antiviral activity was as previously reported for 2-substituted benzimidazoles in animal virus chemotherapy.