bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biosynthesis of 3-Carboxy-6,7-dihydroxy-1, 2,3,4-tetra- hydroisoquinoline and 1-Methyl-3-carboxy-6,7-dihydroxy-1, 2,3,4- tetrahydroisoquinoline in a Callus Culture of Stizolobium hassjoo
Authors: Obata-Sasamoto Hamako , Komamine Atsushi , Saito Koshi 
Published: August 2018

Abstract
ᴅʟ-[β-14C] 3,4-Dihydroxyphenylalanine (DOPA), [2-14C]pyruvate and [2-14C]acetate were ad­ministered to a callus culture of S. hassjoo and incorporation of the radioactivity into 3-carboxy-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (I) and 1-methyl-3-carboxy-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (II) was examined. Incorporation of radioactivity from labelled DOPA into I and II, and from acetate into I were observed, while that from pyruvate into I and II and from acetate into II were hardly detected. The biosynthetic pathways of I and II were discussed.
Anthocyanin Carrying Structures in Specific Genotypes of Matthiola incana R. Br.
Authors: Hemleben V. 
Published: August 2018

Abstract
Several lines of the genetically well defined Matthiola incana (Brassicaceae) concerning the anthocyanin biosynthesis (line 02, 06, 10, and 14) store the anthocyanin pigment as crystals (line 06) or in anthocyanoblasts (“balls”) in the epidermal cells (line 02, 10, and 14) of the flower petals. The genetic constitution of these genotypes is in addition to the basic factors f+, g+, and e+, b+b+ or bb (cyanidin or pelargonidin type), ll, u+u+, and v+v+ or vv, demonstrating that the ll, u+u+ constitution is responsible for precipitation of anthocyanins in a certain structure indepen­ dent of the other modificationally acting genes b and v. The ll, u+u+ types accumulate preferentially acylated 3-biosides.
Regulation of the Synthesis of Ribulose-l,5-bisphosphate Carboxylase and Its Subunits in the Flagellate Chlorogonium elongatum. II. Coordinated Synthesis of the Large and Small Subunits
Authors: Westhoff Peter , Zimmermann Kurt , Boege Frank , Zetsche Klaus 
Published: August 2018

Abstract
Transfer of heterotrophically grown cells of the unicellular green alga Chlorogonium elongatum to autotrophic growth conditions causes a 10 -15 fold increase in the amount of the chloroplastic enzyme ribulose-1,5-bisphosphate carboxylase.
This increase was found to be due to de novo synthesis. The relative proportions of large and small subunits of the enzyme do not change. Their ratio is close to 3.4, the proportions in weight of the two subunits in the holoenzyme. Continous labelling with [35S]sulfate reveals that the ratios of incorporation into large and small subunits are essentially the same in autotrophic and heterotrophic cells.
Pulse-chase experiments show that the subunits are degraded synchronously.
The coordinated subunit synthesis cannot be uncoupled using inhibitors of protein and RNA synthesis or high temperature of cultivation of the alga.
The results suggests a very tightly coordinated synthesis of the large and small subunits of ribulosebisphosphate carboxylase.
Molecular Forms of Purified Cytoplasmatic and Membrane Bound Bovine-Brain-Acetylcholinesterase Solubilized by Different Methods
Authors: Rueß K.-P. , Liefländer M. 
Published: August 2018

Abstract
Membrane bound, Triton X-100 solubilized bovine nucleus caudatus acetylcholinesterase is sedimenting in presence of Triton X-100 concentrations higher than the CMC as a 10.5 S-detergent-enzyme complex. There is evidence that this complex does neither represent the molecular enzyme arrangement present in the membrane, nor the molecular form originally released from the membrane.
The purified, cytoplasmatic acetylcholinesterase is sedimenting as a 10.5 S-form too. This form is clearly to be distinguished from the detergent enzyme complex, for it is obviously not capable of aggregating, whereas the 10.5 S-detergent-enzyme complex aggregates on detergent removal to defined water soluble oligomers with sedimentation coefficients of 16 S (700000 ± 10000), 20.6 S (960000 ± 60000) and 23.3 S (~ 1200000). In contrast to acetylcholinesterase from erythrocytes this aggregation is not easily reversibly by incubation with Triton X-100, reflecting differences in the hydrophobic part of the enzymes.
Purified acetylcholinesterase solubilized without detergent under autolytic or tryptic conditions is mainly sedimenting as a 4.5 S-form. Such slow sedimenting forms detected in crude solubilisates of neuronal tissues, may originate at least partially form autolytic solubilization.
A Family of Sequences with Regional Homology to Bovine 1.715 Satellite DNA
Authors: Skowroński Jacek , Płucienniczak Andrzej 
Published: August 2018

Abstract
The organization of sequences homologous to the bovine 1.715 satellite DNA was studied in the bovine genome. A novel family of sequences, containing different numbers of copies of the 1.4 kb satellite period alternating with 1.2 kb sequence not related to this satellite, was found. Possible mechanism of the generation of these sequences is proposed.
Partial Denaturation Mapping of Phage T4 DNA at Low Temperature
Authors: Grossi G. F. , Macchiato M. F. , Gialanella G. 
Published: August 2018

Abstract
The partial-denaturation map of T4 DNA is obtained by using benzyldodecyldimethyl ammonium chloride in the presence of a high concentration of formamide. In this way suitable conditions for preparation of electron microscope specimens and partial denaturation within a temperature range low enough to minimize the endonucleolytic cleavage, are realized.
It is found that, under our experimental conditions, the denaturation increase depends mainly on the appearance of new denaturation sites rather than on the lengthening of DNA segments already denatured.
Because of the DNA circular permutation it is necessary to align the measured maps to obtain the denaturation pattern. This is done through a computer program and informations on the distribution of the regions with highest (A-T) content along the genome are obtained.
The results of contour length measurements of λ and T4 DNA’s are also reported.
Effects of Linolenic Acid on the Spectral Properties and Picosecond Fluorescence of Pea Chloroplasts
Authors: Brody S. S. , Barber J. , Tredwell C. , Beddard G. 
Published: August 2018

Abstract
Linolenic acid induces changes in the absorption spectrum and in the picosecond fluorescence of pea chloroplasts. The effects of linolenic acid are dependent on concentration and time.
Linolenic acid increases the fluorescence life time of chloroplasts at room temperature. The contribution of the slow fluorescence component relative to the fast component is increased almost 10 fold in the presence of 0.5 mᴍ linolenic acid. The synergistic action of digitonin and linolenic acid increases the ratio of “closed” to “open” traps in the photosynthetic units.
Upon addition of 0.5 mᴍ linolenic acid there are increases in absorbance at 676 and 436 nm, and decreases in absorbance at 705 and 496 nm. Some of the spectral changes have a biphasic character, they reach a maxi um um after about 30 min then start to reverse. Based on the spectral changes at 496 and 705 nm it appears that linolenic acid has at least two effects, i.e. it modifies the thylakoid membrane and secondarily decreases the concentration of P700, respectively.
αβ-Dehydrocurvularin and Curvularin from Alternaria cinerariae
Authors: Robeson David J. , Strobel Gary A. 
Published: August 2018

Abstract
Secondary metabolite production by the phytopathogen Alternaria cinerariae has been investigated resulting in the isolation and identification of αβ-dehydrocurvularin and curvularin as products of this fungus. The phytotoxicity of these compounds is demonstrated.
Glucagon-Like Immunoreactivity (GLI) in Blood Plasma of Partially Hepatectomized Rats
Authors: Strecker W. , Ruhenstroth-Bauer G. , Böttger I. , Pabst H. W. 
Published: August 2018

Abstract
The concentration of substances with glucagon-like immunoreactivity (GLI) was determined in arterial blood plasma of rats up to 4 weeks after partial hepatectomy. 10 h following surgery a more than 18-fold increase in GLI + glucagon immunoreactivity could be observed. About 2/3 of the maximum activity seems to be of non pancreatic origin. The levels returned to normal about 22 h after surgery.
Action Potentials in "Non-Spiking" Visual Interneurones
Authors: Eckert Hendrick E. A. , Hamdorf Kurt 
Published: August 2018

Abstract
The response of the homolateral “horizontal cells” (H-cells) of the third visual neuropile of the blowfly, Phoenicia sericata, has been investigated by intracellular recordings coupled with dye injections (Procion Yellow, cobaltous chloride). Responses were obtained from their terminal axon endings in the central protocerebrum. Under natural conditions, the horizontal cells respond not with graded potentials as reported previously, but with action potentials upon stimulation by regressive pattern motion within the contralateral receptive field. The stimulus-induced responses change from action potentials to graded signals within a few minutes after opening the head capsule. The possible causes of this change, namely hypoxic conditions and a consequent depletion of the ATP-supply, are consistent with the experimental data: a change in the resting potential as well a reduction of the spike amplitude. Furthermore, the possibility of two functionally different output regions of the H-cells is discussed, namely, (1) the terminal axon endings appear to conduct action potentials induced by the contralateral input (to the H-cells). Thus, these endings provide a solely contralateral, i.e. “monocular output”. Whereas (2) the axonal arborisation appears to conduct graded signals elicited by the ipsilateral input onto which the contralateral input is superimposed, thus providing a “binocular output”.
Methylation of 3′,4′ Di-O H C-Glycosyl-flavones in Silene
Authors: Brederode Jan van , Kamps-Heinsbroek Ria 
Published: August 2018

Abstract
In green parts of Silene plants of the genotype glR two methylated flavonoids were found: isoscoparin and isosco-parin 2″-O-rhamnoside. An enzyme has been demonstrated to catalyze the transfer of the methyl moiety of S-adenosyl methionine to iso-orientin and iso-orientin 2″-O-rhamnosi-de. Maximal activity takes place at pH 8.0 -8 .2 . Of the metal ions Mn2+, Mg2+, Ca2+, Co2+, Zn2+ and Hg2+, only Co2+ stimulated the reaction at conc. > 2 mM . For the methyla­ tion of isoorientin the Km values were 4 × 10-6 M for S-ade-nosyl methionine and 0.32 × 10-3 m for iso-orientin. When isoorientin 2″-O-rhamnoside was used as substrate the Km values were 5 × 10-6 m for S-adenosylmethionine and 7 × 10-6 M for iso-orientin 2″-O-rhamnoside.
Electrophoretic and Chemical Studies on the X-Ray Damage of Malate Synthase
Authors: Durchschlag Helmut , Zipper Peter 
Published: August 2018

Abstract
The sulfhydryl enzyme malate synthase was shown to undergo an X-ray induced aggregation and inactivation in solution (Zipper and Durchschlag, Radiat. Environ. Biophys. 18, 99-121 (1980)). Further evidence for the occurrence of aggregation and inactivation and also of fragmen­ tation and partial unfolding of the enzyme upon X-irradiation was obtained by chemical and electrophoretic studies. Irradiation was carried out in a specially designed microcell, experiments were performed on the microlevel. Under conditions of the experiments the formation of H2O2 upon X-irradiation could be proven; therefore the influence of H2O2 on the enzyme was investigated too. Though the quantitative results of the damaged enzyme particles are influenced by many disturbing factors, the findings allow clear statements on the nature of the effects under investigation.
1) Both X-irradiation and treatment with H2O2 caused a decrease of total and an increase of available sulfhydryl groups of the enzyme and led to a loss of enzymic activity. The presence of dithiothreitol turned out to be able to protect the enzyme against X-ray or H2O2 induced inactivation. Moreover, addition of dithiothreitol after X-irradiation or H2O2 treatment allowed a considerable repair of enzymic activity.
2) Polyacrylamide gel disc electrophoreses of X-irradiated enzyme solutions, performed in the presence of sodium dodecyl sulfate, showed the occurrence of covalently cross-linked subunits (preferably dimers and trimers) and of various definite fragments. Electrophoreses in the absence of the denaturant indicated the occurrence of enzyme aggregation. The effects were more pronounced with increasing X-ray doses. The electrophoreses also clearly reflected a radioprotec­ tion by dithiothreitol against cross-linking, but not against fragmentation. Addition of excess of 2-mercaptoethanol or of dithiothreitol to the X-irradiated enzyme clearly demonstrated that part of the covalent cross-links were disulfide bridges; the aggregates themselves, however, were held together primarily by non-covalent bonds. Blocking of exposed enzyme sulfhydryls by means of Ellman's reagent prevented both covalent cross-linking and enzyme aggregation.
3) Similar electrophoretic patterns as found for the X-irradiated enzyme were obtained for the unirradiated enzyme after treatment with H2Oi. The similarity of the electropherograms, as well as the reversible diminution of enzymic activity and the loss of sulfhydryls in the presence of H2O2, suggest an involvement of H2O2 in the radiation damage of the enzyme. It seems plausible that oxidation reactions are responsible for the effects caused by X-irradiation or H2O2 treatment.
18O-Exchange by Hydrolyzing Enzymes: Extension of the Model to Pi Molecules with Inequivalent Oxygen Atoms in the Bound State
Authors: Rösch Paul 
Published: August 2018

Abstract
Enzymes causing an exchange of oxygens from P\ with the surrounding water oxygens are very common. A statistical model for the data evaluation for an observation of this oxygen exchange by isotope methods is presented. It is shown how different cases of inequivalence of the four Pi oxygens may be uncovered. The number of reversals of the oxygen exchange step on the enzyme and the apparent second order rate constant for the binding of Pi to the enzyme are obtained as a result of the data fitting procedure. Cobalt phosphatase, zinc phosphatase, and myosin subfragment 1 are treated as examples.
Protein Kinases in HeLa Cells and in Human Cervix Carcinoma
Authors: Pyerin W. , Baibach N. , Kübler D. , Kinzel V. 
Published: August 2018

Abstract
Extracts of HeLa cell fractions were analyzed by DEAE-and phospho-cellulose chromatog­ raphy for their range of cyclic AMP-dependent and -independent protein kinase activities phosphorylating histone and/or phosvitin; extractions were by phosphate buffered saline (soluble protein kinases) and the non-ionic detergent NP-40 (membrane-bound protein kinases). The soluble fraction contained (i) cyclic AMP-dependent histone kinases type I and II as evidenced by their behaviour on DEAE-cellulose and inhibition by the specific heat-and acid-stable protein kinase inhibitor (PKI) in a dose-related manner; both types I and II as well as their purified catalytic subunit also phosphorylated protamine and — with very low efficiency -casein but not phosvitin; (ii) a histone kinase (H), insensitive to cyclic AMP and PKI, also accepting protamine as substrate but not either casein or phosvitin; (iii) a phosvitin kinase (P), insensitive to cyclic AMP and PKI, which also phosphorylates casein but not histone or protamine. These four enzyme species were also found in NP-40 extracts of 27000x g residues which, however, contained further histone and phosvitin kinase activities as yet unspecified. NP-40 extracts of the microsomal fraction possessed, besides unspecified histone and phosvitin kinase activity, only the phosvitin kinase P and appeared to be devoid of histone kinases I, II, and H. The occurrence and ratios of the protein kinases classified suggest an ordered distribution over the diverse subcellular fractions of HeLa cells. The overall pattern of soluble and membrane-bound histone and phosvitin kinases in extracts of cervix carcinoma tissue, the in vivo correlate of HeLa cells, closely resembled that of similar extracts of HeLa cells. HeLa cells hence appear, despite their long in vitro history, to express protein kinase activities similar to those of their in vivo ancestors, recommending them as a subject for the study of (certain) human protein kinase systems.
On the Specificity of Juvenile Hormone Biosynthesis in the Male Cecropia Moth
Authors: Peter Martin G. , Shirk Paul D. , Dahm Karl H. , Roller Herbert 
Published: August 2018

Abstract
The accessory sex glands (ASG) of adult male Cecropia contain an enzyme that methylates juvenile hormone acids (JH-acids) in the presence of S-adenosyl-L-methionine (SAM). The methyltransferase is highly specific. The reaction rates decrease in the order JH-I-acid, JH-II-acid and JH-III-acid; in each case the natural enantiomer is esterified predominantly. Methyltrans­ ferase activity with the same substrate specificity was also demonstrated in adult female corpora allata (CA). Male CA have only marginal methyltransferase activity. The CA of male H. cecropia contain substantial amounts of JH-I-acid and JH-II-acid (minimum: 5 pmol/pair). When kept in organ culture, they release JH-acids into the medium. Radiolabeled propionate and mevalonate are incorporated efficiently into the carbon skeletons of the JH-acids. The enzyme system performing these transformations cannot be forced to produce JH-III-acid even in the presence of high mevalonate concentrations, though homomevalonate may enhance biosynthesis of JH-I-acid and JH-II-acid more than tenfold. It becomes evident that the regulation of JH titer balances with regard to the homologous structures during insect development is not merely a question of the availability of low molecular weight precursors, but in addition that of highly specific enzymes acting as regulatory entities in the later steps of the biosynthetic sequence.
Iridoide aus einigen Teucrium-und Ajuga-Arten / Iridoids in Some Teucrium and Ajuga Species
Authors: Ruhdorfer Johann , Rimpler Horst 
Published: August 2018

Abstract
of the genus Teucrium and 3 species of the genus Ajuga have been examined for iridoids. Besides the known compounds Harpagid, 8-O-Acetylharpagid, Ajugol, Ajugosid and Reptosid, which we have isolated from species of both genera, two new iridoids Teucardosid (1) [2] and Teuhircosid (5) have been isolated from Teucrium species only. The structure and relative configuration of the new compounds have been determined by spectroscopic methods fH-NMR, 13C-NMR, MS) and some chemical reactions. The taxonomic significance of our results is discussed.
Ferulic Acid-Sucrose Esters from Immature Anthers of Tulipa cv. "Apeldoorn"
Authors: Strack Dieter , Sachs Gesine , Römer Axel , Wiermann Rolf 
Published: August 2018

Abstract
Two ferulic acid conjugates have been isolated from the extract of immature anthers of Tulipa cv. "Apeldoorn" and their structures elucidated using chromatography, electron impact mass spectrometry, and NMR spectroscopy. These two conjugates are 6,3'-diferuloylsucrose and 6,3',4'-triferuloylsucrose. High performance liquid chromatographic analysis of the extract showed that these esters are transient major constituents of the phenylpropanoid pattern of the immature anthers and are present in the ratio of 1:2. Previous investigations showed that these components are accumulated in the loculus.
Über die Zusammensetzung des ätherischen Öls aus Artemisia dracunculus L. während der Vegetationsperiode / On the Composition of the Essential Oil from Artemisia dracunculus L. during the Vegetation Period
Authors: Vostrowsky Otto , Michaelis Karl , Ihm Helmut , Zintl Robert , Knobloch Karl 
Published: August 2018

Abstract
The main components of the essential oil from Artemisia dracunculus L., as there are sabinene, methyl eugenol, estragol and elemicine, are present in variable quantities depending on the season. The biosynthesis of the phenolic compounds in tarragon is in accordance with the shikimate pathway. Elemicine is likely to be a metabolic product of shikimic acid with no further mono-or bisphenolic intermediates involved.
Conversion of Flavanone to Flavone, Dihydroflavonol and Flavonol with an Enzyme System from Cell Cultures of Parsley
Authors: Britsch L. , Heller W. , Grisebach H. 
Published: August 2018

Abstract
Soluble enzyme preparations from irradiated cell suspension cultures of parsley (Petroselinum hortense Hoffm.) catalyse the conversion of flavanone to flavone, dihydroflavonol and flavonol. These reactions require 2-oxoglutarate, Fe2+ and ascorbate as cofactors. In the presence of these cofactors conversion of dihydroflavonol to flavonol was also observed. With this system in vitro biosynthesis of radioactive flavone, dihydroflavonol and flavonol from [2-14C]malonyl-CoA and 4-coumaroyl-CoA in good yield and with high specific activity is possible.
We postulate that synthesis of flavone and flavonol from flavanone proceeds via 2-hydroxy-and 2,3-dihydroxyflavanone, respectively, with subsequent dehydration.
The microsomal fraction of the parsley cells contains an NADPH-dependent flavanone 3'-hydroxylase.
Co+2-Substituted Acylamino Acid Amido Hydrolase from Aspergillus oryzae
Authors: Gilles Ingrid , Löffler Hans-Gerhard , Schneider Friedh. 
Published: August 2018

Abstract
Dedicated to Prof. H. Zahn on the Ocassion of His 65th Birthday Zn+2/Co+2 Exchange, Microbial Acylamino Acid Amido Hydrolase, Aspergillus oryzae, Kinetic Properties The inactivation of the Zn+2 metallo enzyme acylamino acid amido hydrolase from Aspergillus oryzae by ethylendiamine-tetraacetate (EDTA) and nitrilotriacetate (NTA) and the effects of Phe and His on this process were studied. Reactivation of the enzyme by Zn+2-or Co+2-NTA buffer revealed a dissociation constant for the Zn+2-enzyme of 10~10 M and for the Co+2-enzyme of 10-7-5 m. The kinetic properties of the Zn+2 and Co+2 enzyme were compared for a series of substrates. Substitution of Co+2 for Zn+2 reduces substrate specificity of the enzyme.
Cadmium — ein Wachstumsfaktor für den Schiefknolligen Anischampignon Agaricus abruptibulbus (Peck) Kauffmann / Cadmium as a Growth Factor for the Mushroom Agaricus abruptibulbus (Peck) Kauffmann
Authors: Meisch Hans-Ulrich , Scholl Anne-Ruth , Schmitt Johannes A. 
Published: August 2018

Abstract
of Agaricus abruptibulbus, a mushroom which is known to accumulate cadmium, has been isolated and cultivated under definite conditions on agar plates or in a liquid medium in the absence and in presence of cadmium acetate. In.presence of 0.5-1.0 mg/1 Cd, mycelial growth of A. abruptibulbus is enhanced to 80% compared to the Cd-free controls, while above 4 mg Cd/1, the metal began to be inhibitory. The growth promoting effect of Cd was found to be independent from the supply of the organism with zinc.
During growth in presence of Cd, an efficient uptake of the metal into the mycelium took place, a maximal 300 fold enrichment being observed with 10 mg Cd/1. Similar tests were performed with zinc, thereby showing a correlation between the uptake of both elements by the mushroom.
Two Sites of Inhibition of the Photosynthetic Electron Transport Chain by the Herbicide Trifluralin
Authors: Droppa Magdolna , Demeter Sándor , Horváth Gábor 
Published: August 2018

Abstract
The effect of trifluralin on the photosynthetic electron transport has been investigated by oxygen evolution and thermoluminescence m easurem ents. The results confirm the earlier observations that trifluralin at low concentrations blocks electron transport between the two photosystems probably at the same site as DBMIB does. At higher concentrations however, trifluralin inhibits the reaction from H2O →pBQ also and affects the thermoluminescence of chloroplasts in a manner sim ilar to DCMU. These results suggest that trifluralin has a second inhibitory site therefore the use of trifluralin as a specific inhibitor of electron transport has to be questioned.