bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Control of Flavanone 3-Hydroxylase Activity and Flavonoid 3′-Hydroxylase Activity in Antirrhinum majus (Snapdragon)
Authors: Forkmann G. , Stotz G.
Published: August 2018

In flower extracts of defined genotypes of Antirrhinum majus, two different hydroxylases were found catalysing the hydroxylation of naringenin and eriodictyol in the 3-position and of naringenin in the 3′-position. The 3-hydroxylase is a soluble enzyme and belongs according to its cofactor requirement to the 2-oxoglutarate-dependent dioxygenases. Investigations on different genotypes revealed a clear correlation between block of the anthocyanin pathway by recessive alleles of the gene inc and a complete lack of 3-hydroxylase activity. Chemogenetic studies on different genotypes suggested that the 3′-hydroxyl group of the B-ring of flavonoids is introduced at the stage of C15 intermediates. The corresponding 3′-hydroxylase was found to be localized in the microsomal fraction and required NADPH as cofactor. In confirmation of the chemogenetic studies, a strict correlation was found between 3′-hydroxylase activity and the gene eos which is known to control the hydroxylation of flavones, flavonols and anthocyanins in the 3′-position. These results are similar to those previously obtained with Matthioia incana.
Chromophore Content and Molar Absorptivity of Phytochrome in the Pr Form
Authors: Brandlmeier Thomas , Scheer Hugo , Rüdiger Wolfhart
Published: August 2018

Quantitative absorption spectra in the visible and UV region were recorded for denaturated phytochrome (P r) and phytochromobilin peptides in comparison with native Pr. The method was tested with C-phycocyanin from Spirulina platensis. Based on known molar absorptivities for denaturated phycocyanin and suitable model compounds, and on the ratio A620
native/A655-665
degraded = 2.9, ^native was determined to be 102000 m-1 cm-1 for one phycocyanobilin chromophore in native phycocyanin. Likewise, Native was calculated to be 19000 M-1 cm-1. The corresponding ratios for Pr were Anative/Adenatured = 3.4 and Anative/Adegraded = 3.7, this yielded ε665
native = 109000 to 118000 and ε380
native = 36000 M-1 cm-1 for phytochromobilin in native P r. This value corresponds to one phytochromobilin per small phytochrome (60000 D) if data from the literature are corrected for the content of colorless proteins. The latter has been asessed from (i) the purity index (A280/A665) and (ii) the contribution of the phytochromobilin chromophore at 280 nm as derived from model compounds.
X-Ray Crystal Structure Analysis of Factor A (2-Methyladeninyl-cyanocobamide), a Native Vitamin B12-Analogue
Authors: Kopf Jürgen , Deuten Klaus von , Bieganowski Rainer , Friedrich Wilhelm
Published: August 2018

Vitamin B12-factor A (2-Methyladeninyl-cyanocobamide), Vitamin B12, X-Ray Crystal Structure Analysis The crystal and molecular structure of 2-methyladeninyl-cyanocobamide (factor A) has been determined. This compound crystallizes in space group P21212, with a = 2630.6 (15), b = 2210.6 (13) and c = 1592.1 (9) pm. The structure has been solved by the heavy-atom method and refined by least-squares methods on the basis of 3682 X-ray counter data to R = 0.166 and R w = 0.148. As far as we know, this is the first X-ray-investigation of a purine-corrinoid, which differs from cyanocobalamin (vitamin B12) by containing a purine base instead of 5,6-dimethylbenz-imidazole. The structure analysis of 2-methyladeninyl-cyanocobamide shows unambiguously, that the purine base coordinates with cobalt via N B9. The choice of N B9 as coordinative atom can be ascribed partly (or mainly?) to steric influences, since coordination via N B3, which was also discussed, would presumably lead to severe distortion of the nucleotide loop.
Dryopterin, ein neuartiges C17-Flavan aus Dryopteris filix-mas / Dryopterin, a Novel C17-Flavan from Dryopteris filix-mas
Authors: Karl Christian , Pedersen Peter Alsted , Müller Gerhard
Published: August 2018

Dryopteris filix-mas (L.) Schott, Polypodiaceae, Flavan, Dihydrocoumarin, Lactone From acetone extracts of fresh aerial parts of Dryopteris filix-mas (L.) Schott a flavan-3-ol was isolated. Its structure was elucidated as 5-(3,4-dihydroxyphenyl)-3,3a,4,5-tetrahydro-4,8-dihydro-xy-2H-pyrano[4,3,2-ife]-l-benzopyran-2-one by means of spectroscopic methods including l3C-NMR.
Multifunctional Mode of Action of Substituted Nitrodiphenylethers in Scenedesmus Cells
Authors: Sandmann Gerhard , Lambert Rolf , Böger Peter
Published: August 2018

Nitrodiphenylethers substituted with Cl, CF3, and other comparatively simple substituents are compared with respect to their primary effects on the photosynthetic apparatus. These are direct electron-transport inhibition, energy-transfer inhibition (of ATP synthesis), and pigment bleach­ ing, the latter accompanied by decrease of electron transport activity. Certain substituents and their positions at the diphenylether skeleton can be correlated with a particular influence on these phytotoxic effects. The unicellular alga, Scenedesmus, is an appropriate species to fumisch quantitative data on these primary herbicidal modes of action within a 24-h assay period.
Polymethylated Flavonols of Chrysosplenium americanum I. Identification and Enzymatic Synthesis
Authors: Collins F. W. , De Luca Vincenzo , Ibrahim Ragai K. , Voirin Bernard , Jay Maurice
Published: August 2018

Polymethylated Flavonols, Identification, Enzymatic Synthesis, O-Methyltransferase, Chrysosplenium americanum, Saxifragaceae The major flavonoid constituents of Chrysosplenium americanum (Saxifragaceae) were identified by UV-, NMR-and mass spectroscopy and the analysis of their hydrolytic products. They consisted of two 2'-O-β-D-glucosides of partially methylated 2'-hydroxyquercetin and four 5'-O-β-D-glucosides of partially methylated 6-hydroxyquercetin (quercetagetin).

The O-methyltransferase system of this tissue can catalyse the stepwise O-methylation of quercetin, but not quercetagetin, to its 3,7,4'-triOMe-dervative. It is postulated that the latter compound may serve as a branching-point intermediate in the biosynthesis of the naturally occurring O-methylated flavonols of this tissue.
Interactions between Tryptophan Synthase from Escherichia coli and Derivatives of the Coenzyme Pyridoxal 5'-Phosphate
Authors: Merkl Inge , Balk Hubert , Bartholmes Peter , Jaenicke Rainer
Published: August 2018

The interaction of the coenzyme analogues pyridoxal (A), pyridoxine 5'-phosphate (B), pyridoxic acid 5'-phosphate (Q and N-phosphopyridoxyl-L-serine (D) with both the isolated apo β2 subunit and the native < x2 apo β2 bienzyme complex of tryptophan synthase from Escherichia coli has been investigated using enzyme kinetics and CD spectroscopy. A 500-fold molar excess of (A) yields a maximum activation of the a2 apo β2 complex of 12% compared to the native holo bienzyme complex. The corresponding Michaelis constant KM equals 0.16 mM. Compounds (B -D) which lack the reactive carbonyl group in the 4-position cannot act as cofactor during enzymic turnover. However, they are competitive inhibitors with respect to the natural coenzyme pyridoxal 5'-phosphate. The corresponding inhibition constants K\ are for (B): 0.10 mM, (C): 0.03 mM and (D): 0.16 mM.

The CD spectra of the aromatic side chains of both protein species ([@]278nm for the β2 subunit = 26 degr cm2 decimol-1, for the bienzyme complex = 40 degr cm2 decimol-1) remain un­ changed and no measurable dichroic absorption is induced in the visible region at 415 nm upon addition of (A), (at this wavelength productive binding of pyridoxal 5'-phosphate induces a significant extrinsic Cotton effect in the internal aldimine). Reaction with (B) leads to an enhancement of the dichroic amplitude at 278 nm of the isolated β2 subunit {A[6] = 6 degr cm2 decimol-1) and of the a2 β2 complex (zl[0] = 17 degr cm2 decimol-1) respectively. Com­ pound (C) shows no effect in the aromatic region of the β2 subunit, but a decrease in the a2 β2 complex (A[0) = 5 degr cm2 decimol-1). At 315 nm, however, a remarkable extrinsic Cotton effect of + 20 degr cm2 decimol-1 is induced in (Q . Ligand (D) causes a similar increase at 278 nm of A[0] = 14 degr cm2 decimol-1 in both protein species. The given data are discussed on the basis of the mode of binding of the natural coenzyme.
In Vitro Biosynthesis of the Plant Sulpholipid: On the Origin of the Sulphonate Group
Authors: Hoppe Willi , Schwenn Jens D.
Published: August 2018

Biosynthesis of the plant sulpholipid (diacylsulphoquinovosyl glycerol) has been demonstrated in a cell-free assay system from the green alga Chlamydomonas reinhardii CW 15. The sulpholipid was labelled with [35S]sulphate when ATP, Mg2+ and a reductant were provided. Unlabelied cysteic acid failed to suppress the labelling of the sulphonate group in the lipid. Labelling with [35S]PAPS or [35S]sulphite has been studied in a fractionated cell extract. Sulphite as a precursor only required a particulate fraction of the cell while with PAPS the assay had to be complemented with a soluble protein and a thiol compound. [35S]PAPS was incorporated into the diacylsulphoquinovosyl glycerol with a higher specificity than sulphite.
Pyropheophytin a Accompanies Pheophytin a in Darkened Light Grown Cells of Euglena1
Authors: Schoch Siegrid , Scheer Hugo , Schiff Jerome A. , Rüdiger Wolfhart , Siegelman Harold W.
Published: August 2018

Chromatography Light-grown non-dividing cells of Euglena gracilis Klebs var. bacillaris Cori form pheophytin a like pigments from chlorophyll a without loss of viability when they are allowed to incubate in darkness without shaking. This is accompanied by the loss of long-wavelength components in the red absorption band of intact cells. After extraction of these cells with acetone, transfer of the pigments to ether and treatment of the ether solution with dilute acid, two pigments can be separated by high performance liquid chromatography on reverse phase silica gel (RP-8) using methanol: water = 95:5 (v/v) as the eluting solvent: In addition to pheophytin a, the eluate contains an unknown pigment. With increasing times of incubation of the cells in darkness, the proportion of pheophytin a decreases and the proportion of the unknown increases suggesting, that the unknown is formed from pheophytin a. This pigment has been identified as pyropheophytin a. It has the same absorption spectrum as pyropheophytin a (prepared by pyridine pyrolysis of pheophytin a) and contains phytol as the longchain esterifying alcohol. On conversion to the methyl ester, the resulting methyl phorbide is identical with authentic pyromethylpheophorbide a by tic, hplc, absorption, absorption difference and mass spectros­ copy. This is the first report of pyropheophytin a or any pyrochlorophyll derivative from plants or oxygenic plant-like microorganisms where it may serve as an intermediate in chlorophyll degradation.
Mode of Inhibition of Photosynthetic Electron Transport by Substituted Diphenylethers
Authors: Draber W. , Knops H. J. , Trebst A.
Published: August 2018

Several substituted diphenylethers were found to be effective inhibitors of photosynthetic electron flow in isolated thylakoid membranes from spinach chloroplasts. T heir site of inhibition was localized with artificial acceptor and donor systems. The phenylether of an alkyl substituted nitrophenol is prim arely inhibiting electron flow after plastoquinone function whereas a dinitro-phenylether of a phenyl substituted nitrophenol is inhibiting before plastoquinone function. Therefore certain diphenylethers interfere with plastoquinone function at the oxidation or reduction site, depending on the substitution.
Nonlinear Polarisationoscillations in a Biophysical Model-System I: Internal Dynamics
Authors: Kaiser F. , Szabo Z.
Published: August 2018

To describe a metastable electrical dipole state in a biological system. Fröhlich suggested a nonlinear model potential. In this paper we investigate a system of two such dipoles coupled by a dipole-dipole interaction. M athem atically this model is described by two coupled nonlinear differential equations. In the investigation of the dynamics of the system we distinguish three solution types of the equations of motion.
Die Anfangsphasen des durch Steringlucoside und Indol-3-essigsäure stimulierten Wachstums bei Avenakoleoptilen / Initial Phases of Growth Induced by Sterylglucosides and Indole-3-acetic Acid in Avena Coleoptiles
Authors: Tietz Amo
Published: August 2018

The initial phases of growth induced by sterylglucosides were investigated by means of a high resolution recording technique. Avena coleoptile segments were preincubated with 10-6 M IAA in buffered solution, then the β-vglucosides of sitosterol, stigmasterol, campesterol, and cholesterol respectively were added in the concentration range from 10-7 –10-6 m . It could be demonstrated that the first response to the applied sterylglucosides is a reduction of the growth rate lasting about 15 min, followed by a sharp increase of the growth rate. As the growth response of the coleoptiles after treatment with sterylglucosides is very similar to that observed after application o f IAA alone, it is concluded from the results that sterylglucosides or sterols may also exhibit their primary action at the membrane level, perhaps by influencing microviscosity of the membrane and/or H +-secretion.
Direkte allosterische Wechselwirkung von Sauerstoff und Bicarbonat: N-Acetyl-Ala-Ser-Phe, die N-terminale Sequenz der β-Ketten der Hämoglobine des Nilkrokodils (Crocodylus niloticus) und des Mississippi­ krokodils (Alligator mississippiensis) / Direct Allosteric Interaction of Oxygen and Bicarbonate: N-Acetyl-alanyl-seryl-phenylalanine, N-Terminal Sequence of the β-Chains of the Haemoglobins of Nil Crocodile (Crocodylus niloticus) and Mississippi Crocodile (Alligator mississippiensis)
Authors: Schäfer W. , Braunitzer G. , Stangl A.
Published: August 2018

To elucidate the molecular mechanism of the direct allosteric exchange of oxygen and hydrogen carbonate in the hemoglobins of crocodiles, the N-terminal sequence of the β-chains of the crocodiles of the Nile (Crocodylus niloticus) and of the Mississippi (Alligator mississippiensis) was studied. The N-terminal end of the peptide is blocked. By mass spectrometry the N-terminal sequences of both species were found to be N-acetyl-alanyl-seryl-phenyl-alanine. These data explain the absence of hemoglobin-phojphate interaction, the data are in good agreement with the stereochemistry postulated for allosteric exchange of oxygen and hydrogen carbonate in crocodilian hemo­ globins.
Ultrastructure of Differently Pigmented Synechococcus Cells
Authors: Döhler Günter , Barckhausen Ralf , Ruppel Manfred
Published: August 2018

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

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).
Biosynthesis of Photosynthates and Taxonomy of Algae
Authors: Kremer Bruno P. , Kirst Gunter O.
Published: August 2018

The representatives of the major algal divisions including Chlorophyta, Rhodophyta and Heterokontophyta usually show specific patterns of accumulated photoassimilatory products. Among these compounds, the accumulated low-molecular weight carbohydrates such as mono­saccharides, disaccharides, alditols (i.e. polyhydroxy alcohols) and heterosides are of particular interest. Comparative analyses based on photosynthetic 14C-labelling provided sufficient evidence that occurrence and distribution of such compounds are in general indicative for particular algal taxa and in some cases useful biochemical parameters for a classiciation of lower taxa even at the ordinal or the generic levels.
5-Methylcytosin-Gehalt in Rattenerythroleukämie-Zellen nach Induktion mit Dimethylsulfoxid / 5-Methylcytosine Content in Erythroleucemic Cells of Rats after Induction with Dimethylsulfoxid
Authors: Baur R. , Kluge N. , Kröger H. , Wohlert H.
Published: August 2018

Erythroleucemic cells of rats were induced by DMSO for the terminal erythroid differentia­tion. The base composition and the 5MC content of the DNA were analyzed by HPLC and a significant difference between non-induced and induced cells was not found. The analysis of labelled DNA by the restriction enzymes Hha I, Hpa II, and Msp I did not result in a different pattern before and after the induction. These results suggest that the 5 MC content of the DNA does not change during the induced terminal erythroid differentiation.
Katabole Eigenschaften 5',5"-verknüpfter Dinucleosidphosphate in Nuclei aus Rattenleber / Catabolic Properties of 5',5"-Linked Dinucleosidephosphates in Rat Liver Nuclei
Authors: Bornemann Siegmar , Schlimme Eckhard
Published: August 2018

We report on the enzymatic degradation of 14C-labelled 5',5"-linked dinucleoside triphosphates Gp3A, 2-O-mGp3A, 2'dGp3A, 2',3"ddGp3A and m7Gp3A in rat liver nuclei. The 2'-desoxy- and 2',3'-didesoxy compounds are poorer substrates than the other cap-structured dinucleotides in­vestigated.
Antibiotika aus Basidiomyceten, XV [1]. 1-Hydroxy-2-nonin-4-on, ein antifungischer und cytotoxischer Metabolit aus Ischnoderma benzoinum (Wahl.) Karst. / Antibiotics from Basidiomycetes. XV [1]. 1-Hydroxy-2-nonyn-4-one, an Antifungal and Cytotoxic Metabolite from Ischnoderma benzoinum (Wahl.) Karst.
Authors: Anke Timm , Giannetti Bruno-Max , Steglich Wolfgang
Published: August 2018

A new antibiotic, 1 -hydroxy-2-nonyn-4-one (1), has been isolated from submerged cultures of several strains of Ischnoderma benzoinum. The compound exhibits high inhibitory activity against yeasts and filamentous fungi at concentrations of 1-5 μg/ml. DNA, RNA, and protein syntheses in cells of the ascitic form of Ehrlich carcinoma are strongly inhibited by the same concentrations.
Differential Fluorescence and Kinetic Studies on the Template-Binding of RNA Polymerase from Parsley and Escherichia coli
Authors: Grossmann K. , Bisswanger H. , Seitz H. U.
Published: August 2018

A fluorescence spectroscopy method is described for studying association of RNA polymerase with DNA templates. Using double beam differential fluorescence at excitation and emission wavelengths of 285 and 335 nm, respectively, the new technique discriminates non-specific decrease of fluorescence intensity by addition of DNA from quenching of polymerase fluorescence by protein-nucleic acid interactions. Comparing the results with studies of UMP incorporation into RNA, the Ks-values of template-binding were in good agreement with the values for RNA synthesis, pointing to specific interaction of polymerase and the DNA template measured by the fluorescence method. While E. coli enzyme showed higher affinity for templates such as heat- denatured poly [d(A-T)] and poly [d(G-C)] parsley RNA polymerase I accepted such templates with the same affinity as salmon sperm DNA. It is obvious that divalent cations are not necessary for the interaction of both enzymes with single-stranded DNA-templates. UMP incorporation studies suggest that transcription is a cooperative process.
Sensitivity of Escherichia coli to Viral Nucleic Acid. XVI. Temperature Conditions for Ca2+-Dependent DNA Uptake in Escherichia coli
Authors: Taketo Akira
Published: August 2018

Properties of Ca2+- or Ba2+-dependent transfection and transformation in Escherichia coli were examined, using ΦX174 replicative-form (RF) DNA and plasmid DNA. For the transfection and transformation, a heat pulse step was dispensable and the yield of transfectants was, in most E. coli strains, rather reduced by the heat treatment. The heat pulse step was also detrimental for the transformation of certain strains such as lipopolysaccharide mutants. The first stage of the DNA uptake process (formation of DNA · recipient cell complex) was dependent on low temperature and Ca2+ ion. A substantial amount of the complexed RF-DNA was released from the bacteria, by washing with a chilled Tris buffer. Although a RF-DNA · cell complex was formed even at 37 °C or in chilled 0.05 ᴍ MgCl2, the complex did not yield transfectants.
Nanochlorum eucaryotum: a Very Reduced Coccoid Species of Marine Chlorophyceae
Authors: Wilhelm Christian , Eisenbeis Gerhard , Wild Aloysius , Zahn Rudolf
Published: August 2018

Nanochlorum eucaryotum was isolated from a sea water aquarium housing different sponge species, cucumarias, small crustaceans and annelids. This bright green marine alga differs from all other known coccoid species. Its most prominent features are its very small cell size (1.5 pm) and its reduced cellular organization. Its cell contains one nucleus, one chloroplast, one mitochondrium and small vacuoles. Sometimes a Golgi apparatus can be seen. No other subcellular features have been observed. The cell wall is thin and smooth and does not contain any material of high electron density; only dividing cells show a rougher surface. The cells split into two daughter cells. No sexual reproduction has been observed in this organism. We have analyzed the ultrastructural cell organization, the amount of total DNA and RNA per cell, the pigment composition, the growth requirements and the sensitivity towards different inhibitors (chloramphenicol, cycloheximid, penicillin, lysozym and cellulase). The results afford the introduction of a new species; a new family or suborder of coccoid green algae is discussed.
Growth and Photosynthesis of Nanochlorum eucaryotum, a New and Extremely Small Eucaryotic Green Alga
Authors: Wilhelm Christian , Wild Aloysius
Published: August 2018

Nanochlorum eucaryotum is a very small species of unicellular coccoid green algae (1.5 pm). The growth of Nanochlorum under different conditions of salinity, pH and light intensities was studied. Optimal growth rates were observed with normal sea water salinity and low light conditions at pH 7.0. The contents of chlorophylls, carotinoids, soluble proteins and the chlorophyll a to chlorophyll b ratio were measured. The light saturating curves of Nanochlorum cells grown under light intensities of 100 lx, 2000 lx and 10000 lx reveal a very narrow capacity of light adaptation. When cultured under higher light intensities, Nanochlorum was not able to reach high photosynthetic activities but underwent a photoinhibition of photosynthesis. The contents of cytochrome f, P-700 and ribulosebisphosphate carboxylase were low and comparable with those of low light adapted Chlorella cells. The analysis of the chlorophyll-protein complexes shows that about 80% of total chlorophyll is bound in the light harvesting chlorophyll protein complexes. All results indicate that Nanochlorum is a low light adapted marine organism with very narrow ecological flexibility.
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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.
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

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

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

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.