bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of the Peptide Chain of 124 kDa Phytochrome: Localization of Proteolytic Fragments and Epitopes for Monoclonal Antibodies
Authors: Grimm Rudolf , Lottspeich Friedrich , Schneider Hansjörg A. W. , Rüdiger Wolfhart 
Published: August 2018

Abstract
Isolated oat phytochrome (124 kDa) was digested with endogenous proteases from oat and with trypsin. Fragments were isolated by SDS polyacrylamide gel electrophoresis (PAGE) blotted onto an activated glass fiber sheet and applied to microsequencing. Comparison of the amino terminal sequences of the fragments with the complete amino acid sequence derived from DNA sequence studies (Hershey et al., Nucleic Acid Res. 13, 8543 - 8560, [1985]) allowed the exact localization of each fragment. The reaction of the various fragments with monoclonal antibodies raised against 114/116 or 124 kDa oat or maize phytochrome were tested by means of Western blotting. Differential reactivity of the localized fragments allowed the localization of epitopes for several antibodies.
Effect of External Calcium Concentration on the Intensity Dependence of Light-Induced Membrane Current and Voltage Signals in Two Defined States of Adaptation in the Photo-Receptor of Limulus
Authors: Stieve H. , Gaube H. , Klomfaß J. 
Published: August 2018

Abstract
The intensity dependence of the response of the Limulus ventral nerve photoreceptor to light flashes was determined in alternating measurements for the membrane current signal (receptor current) under voltage clamp conditions and the membrane voltage signal (receptor potential). Responses were obtained at two reproducible states of adaptation, while the photoreceptor was superfused by physiological saline (10 mmol/l Ca2+), or by salines with either lowered (250 μmol/l) or raised (40 mmol/l) calcium concentration.
For the dark-adapted state of the photoreceptor the double logarithmic plot of the response current-time integral F (or the current amplitude) vs. flash intensity rises in a steep, supralinear section (slope 2-4) to a curve knee towards a less steep, sublinear section (slope 0.2-0.6), but does not reach saturation in the intensity range tested. Light adaptation shifts the response size vs. intensity curve towards higher light intensities. This sensitivity shift is enlarged in raised, and almost abolished in low external [Ca2+].
The changes of response latency and time-to-peak with stimulus intensity or adaptation are almost identical for receptor current and receptor potential. The decrease-time of the receptor current response, however, depends much less on the stimulus intensity or the state of adaptation than that of the receptor potential. The relative changes in the time course of the receptor current caused by light adaptation are not much influenced by variation of the [Ca2+]ex.
Interpretation: The macroscopic receptor current signal consists of a volley of overlapping bumps; the size of these bumps is scaled by a calcium-dependent attenuation function which increases with delay time. This gradual growing attenuation a(t) acts as automatic gain control and may be responsible for the sublinear slope of the intensity dependence of the size of the receptor current. The supralinear slope of this dependence at lower stimulus intensities is probably caused by cooperative effects. Changes in the time course of the macroscopic receptor current due to light adaptation or varied calcium concentration are based on changes in the latency distribution of the underlying bump volley, and the size of the attenuation function.
Rearrangement of Glaucolide A into Vernojalcanolide 8-O-Methacrylate
Authors: V. Mariano Martínez , F. Antonio Sánchez , B. Guadalupe López , Joseph-Nathan Pedro 
Published: August 2018

Abstract
The isolation of vernojalcanolide 8-O-methacrylate, a cadinanolide sesquiterpene from Vernonia morelana D .C . is described. The rearrangement of glaucolide A into ver­nojalcanolide 8-O-methacrylate is also reported. Biogene­tic aspects are briefly discussed.
Microfilament-Supported Macrovilli in the Hindgut of the Polychaete Dinophilusgyrociliatus
Authors: Oster Ulrich 
Published: August 2018

Abstract
Large macrovilli of 7.7 μm maximal length and a diameter of 0.4 μm with several hundred cytochalasin B-sensitive 6 nm microfilaments are found as bordering lateral struc­tures in the ciliary groove of the hindgut of Dinophilus gyrociliatus. The microfilament bundle, accompanied by microtubules, extends with its tapering rootlets to the base of the cells. Another cell type in the middle of the groove bears the cilia and equally broad, but shorter macrovilli with a cytochalasin-sensitive microfilament core.
Increased Lipoxygenase Activity is Involved in the Hypersensitive Response of Wheat Leaf Cells Infected with A virulent Rust Fungi or Treated with Fungal Elicitor
Authors: Ocampo Carlos A. , Moerschbacher Bruno , Grambow Hans J. 
Published: August 2018

The hypersensitive reaction in incompatible wheat-rust interactions is characterized by an increase in lipoxygenase activity detectable as early as 28 h after penetration of the pathogen. In contrast, lipoxygenase activity in the compatible interaction did not increase until the onset of sporulation.
Lipoxygenase activity also increased following treatment of wheat leaves with an elicitor fraction from germ tubes of Puccinia graminis tritici.
Esters of Benzyl Alcohol and 2-Phenyl-ethanol-1 in Epicuticular Waxes from Jojoba Leaves
Authors: Gülz Paul-Gerhard , Marner Franz-Josef 
Published: August 2018

Abstract
Esters of very long chain fatty acids with benzyl alcohol and the homologue 2-phenyl-ethanol-1 were found in the epicuticular waxes from Jojoba (Simmondsia chinensis) leaves. The isolation of these esters by chromatographic methods, the structural elucidation by GC-MS and their chemical reactions and synthesis are described.
UDP-Glucose: Anthocyanidin/FIavonol 3-O-Glucosyltransferase in Enzyme Preparation from Flower Extracts of Genetically Defined Lines of Matthiola incana R. Br.
Authors: Teusch M. , Forkmann G. , Seyffert W. 
Published: August 2018

Abstract
In flower extracts of Matthiola incana an enzyme catalyzing the transfer of glucose from UDP- glucose to the hydroxyl group at 3-position of anthocyanidins and flavonols was demonstrated. The pH-optimum of this reaction is at pH 8.5 for pelargonidin and pH 9.5 for quercetin as substrate. The reaction is inhibited by both substrates above 10 nmol per assay. The enzyme is highly active, within 30 sec 3 nmol of 3-glucosides were formed. At 30 °C the enzyme is stable for hours and at -20 °C months. Besides UDP-glucose, TDP-glucose is a suitable glucosyl-donor, but with a reduced (70%) reaction rate. Enzyme activity is clearly inhibited by Fe2+ and Cu2+ ions, and by diethylpyrocarbonate. Acyanic or pale coloured mutants of several genes interfering with anthocyanin synthesis after dihydroflavonol formation show a more or less drastically reduced enzyme activity (5-40%). But none of these genes can be regarded as the structural gene for the 3-glucosyltransferase. The influence of these genes on enzyme activity and flower colour is dis­cussed.
Cyanidin 3-Oxalylglucoside in Orchids
Authors: Strack Dieter , Busch Ekkehard , Wray Victor , Grotjahn Lutz , Klein Erich 
Published: August 2018

Abstract
A new acylated anthocyanin has been isolated from flowers of Nigritella and Orchis and identified as cyanidin 3-O-β-(6”-O-oxalyl)-glucoside on the basis of TLC , HPLC , FABMS, 1H and 13C NMR . This pigment was found to be present in various members of the Orchidaceae.
Nitrogen and Sulfur Starvation of the Cyanobacterium Synechococcus 6301 An Ultrastructural, Morphometrical, and Biochemical Comparison
Authors: Wanner G. , Henkelmann G. , Schmidt A. , Köst H.-P. 
Published: August 2018

Abstract
The effects of nitrogen and sulfur limitation on various cellular parameters of the cyanobacterium Synechococcus 6301 were studied by electron microscopy, morphometry and biochemical methods. Nitrate and sulfate starvation for 70 h results in a massive glycogen accumulation in parallel to a loss of soluble protein and chlorophyll. Phycobilisomes disappear prior to the degradation of photosynthetic membranes. For sulfate-starved cells, a formation of “storage granules” (poly-β-hydroxy-butyric acid) is typical which amount up to 10% of the cell volume. The composition of polar lipids is simple: equal parts of C 16:0 and C 16:1 are present under all nutritional conditions; their amount is directly correlated with the total cellular membrane area as deter­mined by morphometry.
Nitrate starved cells regenerate almost completely in structure and composition within 9 h after nitrate supplementation. Regeneration of sulfate starved cells is retarded; in spite of significant synthesis of phycocyanin within 9 h the cells still exhibit marked signs of starvation.
Conjugated Enamino Compounds, a New Molecular Probe for the Mechanism of Photosynthetic Electron Transport
Authors: Asami Tadao , Takahashi Nobutaka , Yoshida Shigeo 
Published: August 2018

Abstract
A series of 2-(1-alkylamino)vinylidene-1,3-cyclohexanedione was synthesized and assayed as inhibitors of the Hill reaction in isolated chloroplasts. The pI50 value of this series was dramatically changed by modification of the peripheral of its hydrophilic moiety and the maximum pI50 value of this series was almost equal to that of DCMU . The results suggest that this series may be a good probe for searching the environment of inhibitors binding site because of its chemical and biological characteristics and its ease of synthesis.
Azadirachtin, a Chemical Probe for the Study of Moulting Processes in Rhodnius prolixus
Authors: Garcia Eloi S. , Uhl Marianne , Rembold Heinz 
Published: August 2018

Abstract
The effects of azadirachtin A after injection into timed 4th-instar nymphs of Rhodnius prolixus were studied. A dose-response relationship of Aza A was established using moulting inhibition and mortality as effective parameters. Aza A , if injected 1 to 3 days after blood feeding, inhibited the moulting process. However, if injected during and after the onset of epidermal mitosis, ecdysis was not affected. A single dose of Aza A was able to block the onset of mitosis in the epiderm is, which is associated with the moulting cycle and is triggered by moulting horm one. Ecdysteroid titres, determined by radioimmunoassay, were too low for an induction of ecdysis in the Aza A treated nymphs. During the peak maximum, the predom inant ecdysteroid was 20-hydroxyecdysone. The conjugated ecdysteroids were based on 20-hydroxyecdysone and ecdysone in the same ratio. The significance of these findings in relation to the possibility of Aza A to act either directly on the prothoracic glands or indirectly through releasing sites in the brain or through Corpus allatum is discussed.
Protein Phosphorylation — Dephosphorylation in the Cytosol of Pea Mesophyll Cells
Authors: Hracky Ruth , Soll Jürgen 
Published: August 2018

Abstract
Soluble protein kinase and protein phosphatase activities were localized in the cytosol of pea mesophyll cells using protoplasts fractionation techniques. The molecular weights of the phosphorylated cytosolic proteins, as determined by polyacrylamide gel electrophoresis, were 68, 55, 46, 38, 36, 30, 22 and 12 kDa. Histone and, to a much lesser extent, casein but not phosvitin were accepted as exogenous substrates. In every case serine served as acceptor amino acid for the phosphate residue. The protein phosphorylation activity had an alkaline pH optimum, and showed no response to varying Mg-2, Ca2+, Pi cyclo-AMP or calmodulin concentrations. The kinase activity was competitively inhibited by ADP and pyrophosphate with apparent Ki values of 0.5 and 0.17 mᴍ , respectively. High ATP concentrations (1-4 mᴍ) resulted in a strong decrease of radioactivity in the 32P labeled proteins. It is proposed that the ratio of protein phosphorylation to protein dephosphorylation is regulated by the ATP to ADP ratio in the cytosol.
Biosynthesis and Turnover of Cell Wall Glycoproteins during the Vegetative Cell Cycle of Chlamydomonas reinhardii
Authors: Voigt Jürgen 
Published: August 2018

Abstract
Biosynthesis and turnover of the different cell wall components have been studied during the vegetative cell cycle of Chlamydomonas reinhardii by pulse-labelling with [3H]proline and [35S]methionine and by pulse-chase experiments. Two phases of biosynthesis of insoluble cell wall material could be distinguished:
1. de novo synthesis of the daughter cell walls during cytokinesis and
2. cell wall enlargement during cell growth.
During the cell enlargement period, a turnover of the insoluble wall component was observed.
The released fragments were found to be accumulated in the culture medium.
The LiCl-soluble cell wall glycoproteins were found to be precursors of the insoluble cell wall layer. Biosynthesis of the LiCl-soluble cell wall glycoproteins was observed mainly during the time period between cytokinesis and the end of the following cell enlargement period. Labelling of all the cell wall components was found to be strongly reduced during the time period between the end of the growth phase and cytokinesis.
During cytokinesis, labelling of the insoluble cell wall material preceded the incorporation of radioactive precursors into the LiCl-soluble wall fraction.
The C-Glycosylflavone Pattern of Passiflora incamata L.
Authors: Geiger Hans , Markham Kenneth R. 
Published: August 2018

Abstract
From the herbage of Passiflora incarnata have been isolated eight flavone-C-glycosides based on apigenin and luteolin, six of them had not been found before in that plant. The constitution of all compounds is prooven.
Magnetotactic Bacteria from Freshwater
Authors: Oberhack Matthias , Süssmuth Roland , Frank Hermann 
Published: August 2018

Abstract
Four species of magnetotactic bacteria have been detected in alkaline waters with pH 7.4-8.7. They were of coccoid to rod-like shape. Each of the species showed different patterns of movement. Two various types of magnetosomes, a chain-like arrangement and a scattered distributional pattern and a lateral polytrich flagellated type could be demonstrated with the coccoid species.
Characterization of Some Claviceps Strains Derived from Regenerated Protoplasts
Authors: Schumann Brigitte , Maier Walter , Gröger Detlef 
Published: August 2018

Abstract
Three ergoline alkaloids producing Claviceps strains easily formed protoplasts when treated with snail digestive extract ex Helix pomatia. Colonies obtained after regeneration of protoplasts were monitored for alkaloid production. Among the regenerated progeny strains could be isolated which differ considerably in the quantity of ergolines and the composition of the alkaloid mixture compared with parental strains. Protoplast-derived strains were stable in morphology and alkaloid production for more than four years if the propagation was performed with hyphal fragments. Activities of some alkaloid-specific enzymes e.g. oxygenases and ergotamine syntheta­se were studied in various related strains.
Semicontinuous and Continuous Production of Citric Acid with Immobilized Cells of Aspergillus niger
Authors: Eikmeier H. , Rehm H. J. 
Published: August 2018

Abstract
The citric acid excretion of Ca-alginate-immobilized cells of Aspergillus niger in batch culture decreased with a half-time of approximately 19 days. Reactivation of the biocatalysts by regeneration in growth medium was possible, but it was followed by a submerged sporulation of the fungus, and medium was highly contaminated with free cells. Citric acid production could better be prolonged by semicontinuous cultivation with medium exchange every 7 or 14 days, respectively. After 32 days the remaining activity in semicontinuous culture was 1.4-fold higher than in comparable batch experiments. Similar improvements were obtained with a continuous process at a dilution rate of 0.125 v/v · d, whereby medium efflux completely free of detaching mycelia.
Functional Group Recognition of Pheromone Molecules by Sensory Cells of Antheraea polyphemus and Antheraea pernyi (Lepidoptera: Saturniidae)
Authors: Bestmann H. J. , Cai-Hong Wu , Döhla B. , Li-Kedong  , Kaissling K. E. 
Published: August 2018

Abstract
The pheromone components of A. polyphemus, (6 E, 11 Z)-6 ,11-hexadecadienyl acetate and (6 E, 11 Z)-6 ,11-hexadecadienal, both effective also in A. pernyi, were synthetically varied in their chemical structures and these compounds electrophysiologically tested in single cell recordings. It appeared that for the interaction between the signal molecule and the receptor region at the dendritic membrane of the receptor cell the electronic character of the functional end group (acetate or aldehyde) of the stimulus molecule is important. The excitation of the sensory cell also depends on the chain length.
Synthesis, Analysis and Characterization of the Coenzyme A Esters of o-SuccinyIbenzoic Acid, an Intermediate in Vitamin K2 (Menaquinone) Biosynthesis
Authors: Kolkmann Rainer , Leistner Eckhard 
Published: August 2018

Abstract
One of the carboxyl groups of o-succinylbenzoic acid (OSB, 1) is activated during the biosyn­ thesis of vitamin K2 and anthraquinones. In an attempt to determine the exact structure of the naturally occurring OSB coenzyme A thioester, the three possible esters were prepared via the imidazolides of OSB. HPLC systems were developed for the successful separation of the esters and their structural analogues. The structures of the coenzyme A esters were investigated and their products of hydrolysis determined quantitatively. Two of the esters were highly labile at pH 7 and 30 °C. UV spectroscopy is a suitable method to distinguish between different positions of activation. Fast atom bombardment mass spectrometry was successfully employed to charac­ terize two of the esters.
The data strongly indicate that the “aliphatic” coenzyme A ester is the intermediate in vitamin K2 and anthraquinone biosynthesis.
Energy-Dependent Chlorophyll Fluorescence Quenching in Chloroplasts Correlated with Quantum Yield of Photosynthesis
Authors: Krause G. Heinrich , Laasch Henrik 
Published: August 2018

Abstract
Chlorophyll a fluorescence quenching was studied in intact, CO2 fixing chloroplasts isolated from spinach. Energy-dependent quenching (qᴇ), which is correlated with the light-induced pro­ ton gradient across the thylakoid membrane presumably reflects an increase in the rate-constant of thermal dissipation of excitation energy in the photosynthetic pigment system . The extent of qᴇ was found to be linearly related to the decrease of quantum yield of photosynthesis. We suggest that this relationship indicates a dynamic property of the membrane to adjust thermal dissipation of absorbed light energy to the energy requirement of photosynthesis.
Reactivation of Streptolysin S by Oligonucleotide
Authors: Taketo Akira , Taketo Yoriko 
Published: August 2018

Abstract
Oligonucleotide-streptolysin S complex inactivated by alkali treatment remains nonhemolytic, even after acidification and mixing with intact carrier oligonucleotide rich in guanyl residue. Upon dehydration, how ever, the inactive streptolysin S-oligonucleotide mixture turned to be hemolytic, and this reactivation of the hem olysin was promoted by treatment with guanidine hydrochloride. After alkaline hydrolysis, streptolysin S was freed from nucleotide moiety, by gel filtration through a Sephadex G -50 column. From this nonhemolytic apotoxin as well, active streptolysin S complex was reconstructed upon dehydration with the carrier.
Cyanoacrylate Inhibitors of the Hill Reaction IV. Binding Characteristics of the Hydrophobic Domain
Authors: Huppatz John L. , Phillips John N. 
Published: August 2018

Aryl- and aralkyl-amino derivatives of 2-cyanoacrylic esters were synthesized and assayed as inhibitors of the Hill reaction in isolated pea chloroplast fragments.
Aryl- and aralkyl-amino 2-cyanoacrylates unsubstituted in the β-position were weak inhibitors but activity could be greatly enhanced by inclusion of a β-alkyl group with the increase in potency being dependent on the carbon chain length of the β-substituent. The magnitude of this effect appeared independent of the nature of the aryl- or aralkyl-amino function.
Inclusion of a carbon chain between the phenyl and amino functions of phenylamino-2-cyano- acrylates produced a stepwise increase in activity with increasing chain length, indicating a prefer- red orientation for the phenyl ring within the hydrophobic binding domain.
Interconversion of Prenyl Pyrophosphates and Subsequent Reactions in the Presence of FMC 57020
Authors: Sandmann Gerhard , Böger Peter 
Published: August 2018

In vitro studies of the influence of FMC 57020 on terpenoid biosynthesis have shown that this herbicide acts at an early stage. It affects the conversion of isopentenyl pyrophosphate to geranylgeranyl pyrophosphate catalyzed by isopentenyl pyrophosphate isomerase and prenyl transferase. An inhibition of the carotenogenic enzymes phytoene desaturase, ζ-carotene desaturase, and lycopene cyclase could be excluded.
Comparison of I50 values for in vivo chlorophyll, carotenoid, ergosterol and gibberellin biosyn- thesis as well as in vitro formation of phytoene. phytol and kaurene in various autotrophic and heterotrophic organisms have shown that terpenoid biosynthesis in the chloroplast is much stronger affected than extraplastidic terpenoid formation.
Chemical Control of Photorespiration: Steady-State Kinetic and Conformational Changes of Ribulose-1,5-bisphosphate Carboxylase/Oxygenase Obtained with O-p-Nitrophenylhydroxylamine
Authors: Van Assche C. J. , Reinier N. , Courtiade B. , Chancel A. , Huber S. 
Published: August 2018

Spinach RuBP carboxylase-oxygenase (Rubisco) purified from the commercially available enzyme, underwent kinetic changes when micromolar concentrations of O-p-nitrophenylhy- droxvlamine (NPHA) were applied on fully activated enzyme. Under steady-state conditions, a decrease of Km CO2 was observed without changes in Vmax. Double reciprocal plots showed a competitive stimulation of carboxylase function. The substrate specificity factor k = Vc Ko/Vo Kc was increased from approximatively 15-20% upon treatment with NPHA, using both parallel and simultaneous determinations of RuBP-carboxylase and oxygenase activities.
Such a limited change in partition between Rubisco functions actually resulted into an increase in CO2 fixation of intact soybeans leaves treated with NPHA. arising from a substantial alleviation of O2-inhibition of photosynthesis.
From spectrophotometric and sulfhydryl group titration data, evidence was accumulated for a conformational change of the native enzyme, induced by NPHA. bringing about an increased ratio of carboxylase to oxygenase activities. Direct interaction of NPHA with a cysteine residue of Rubisco near the catalytic site, appears as a candidate for such chemically-induced conformational modification.
Structure of Azadirachtin B
Authors: Rembold Heinz , Forster Hans , Sonnenbichler Johann 
Published: August 2018

Abstract
The structures of azadirachtin B and of detigloylazadirachtin have been determined on the basis of detailed 1H and 13C NMR spectroscopic analysis. Comparison of the data from both com pounds unequivocally proves esterification by tiglic acid at position 3. Our data thus confirm the structure as proposed by Klenk et al., J. Chem. Soc., Chem. Commun. 1986, 523-524.
Pflanzenabwehrstoffe XXXI [1] Molluskizide Eigenschaften von Chinonen
Authors: Schildknecht Hermann , Lubosch Johannes 
Published: August 2018

Abstract
The quinone 2-methoxy-6-n-pentyl-2,5-cyclohexadien-1,4-dion (Primin) was found to possess molluscicidal activity against the snail Planorbis corneus. The synthesis of homologous and isomers and the results in the biotests are reported.