bluuebunny/crossref_metadata_2025_split huggingface dataset:
Host-Pathogen Interactions XXX. Characterization of Elicitors of Phytoalexin Accumulation in Soybean Released from Soybean Cell Walls by Endopolygalacturonic Acid Lyase
Authors: Davis Keith R. , Darvill Alan G. , Albersheim Peter , Dell Anne 
Published: August 2018

Abstract
Endopolygalacturonic acid lyase, purified from the phytopathogenic bacterium, Erwinia carotovora, induces phytoalexin accumulation in soybean (Glycine max L.) cotyledons. This pectin-degrading enzyme releases heat-stable elicitors of phytoalexin accumulation from soybean cell walls, citrus pectin, and citrus sodium polypectate. The most elicitor-active molecules ob­tained by treating soybean cell walls with endopolygalacturonic acid lyase have been purified and characterized. The cell-wall-derived elicitors are α-1,4-linked oligogalacturonides with degrees of polymerization of eight to twelve residues. The molecules with the highest specific elicitor activity were identified as α-1,4 -linked deca- and undecagalacturonides that contained 4,5-unsaturated galactosyluronic acid at the nonreducing termini.
Degradation of NAD(H) by Endogenous Enzymes of Yeasts and Clostridia
Authors: Schuetz Hans-Jürgen , Simon Helmut 
Published: August 2018

Abstract
The time courses of degradation of exogenous NAD and NADH (2.5 mᴍ) catalyzed by endogenous enzymes present in Saccharomyces cerevisiae, Candida utilis, Clostridium spec. La 1, Clostridium kluyveri, and Clostridium sporogenes have been determined. The half lives of the pyridine nucleotides depend extremely on the organism and, for the same organism, on the growth conditions. C. spec. La 1 as well as C. kluyveri possess only negligible enzyme activities for NAD degradation. However, C. sporogenes shows activities leading to half lives of less than 2 h for NAD and 5 h for NADH. At 25 °C half lives in the order of 5-17 h have been observed for Candida utilis under different conditions. The half lives of NAD are roughly 5 times higher in the presence of Saccharom yces cerevisiae.
Composition of Lipopolysaccharides from Various Strains of Rhodomicrobium vannielii
Authors: Holst Otto , Weckesser Jürgen , Rieth Baldur , Dow Crawford S. 
Published: August 2018

Abstract
The compositions of lipopolysaccharides from the photoheterotrophic budding Rhodomi­crobium vannielii strains DSM 162, Rm5, E3 and 2/1 are reported. Common constituents of these lipopolysaccharides are glucose, mannose, glucosamine, glucuronic and galacturonic acids, 2-keto-3-deoxyoctonate (KDO) and the fatty acids 3-OH-C16:0, 3-OH-C14:0, C14:0, Δ14-C22:1, aside from strain specific differences.
Two different, medium-dependent growth forms of strain DSM 162 are described. The vitamin/ yeast extract-concentration in the medium and/or the growth temperature were found as factors triggering the different growth forms. Lipopolysaccharides of the two growth forms had only quantitative differences in composition. Lipopolysaccharide from swarmer cells of strain Rm5 showed a chemical composition comparable to that of chain cells and from simple cycle cells of the same strain.
Further Studies on the Biosynthesis of Granaticin
Authors: He Xian-guo , Chang Chiu-Chin , Chang Ching-jer , Vederas John C. , M clnnes A. Gavin , Walter John A. , Floss Heinz G. 
Published: August 2018

Abstract
Experiments with cerulenin-inhibited cultures of 5. violaceoruber showed conversion of dihydrogranaticin (II) into granaticin (I), but not vice versa, confirming an earlier conclusion that II is the biosynthetic precursor of I. Feeding of CH3
13C18O2Na followed by 13C-NMR analysis of the product by the 18O shift method indicated the expected incorporation of 18O at carbons 1,11 and 13 of I and showed that the oxygen of the pyran ring originates from C-3 and not from C-15. Analysis of I biosynthesized from 13C2H3COONa by 13C{1H, 2H} triple resonance NMR spectro­scopy showed the incorporation of one atom of deuterium each at C-2 and C-4. C-16 carried a maximum of 2, not 3, atoms of deuterium. These results are discussed in terms of biosynthetic mechanisms.
The Topology of the Plastoquinone and Herbicide Binding Peptides of Photosystem II in the Thylakoid Membrane
Authors: Trebst Achim 
Published: August 2018

Abstract
The 32 kDa herbicide and QB binding peptide (D-1 protein) and its homologous 34 kDa peptide (D-2 protein) are integral membrane subunits of photosystem II. A model for their folding through the thylakoid membrane in five transmembrane a-helices is proposed from the compari­son of amino acid sequence and hydropathy index plot homologies with subunits of the bacterial system. Following recent data on the X-ray structure of a bacterial photosystem the binding niche for QB is interpreted on the basis of the amino acid changes found in the 32 kDa peptide in herbicide tolerant higher plants and algae.
Rhizomnium magnifolium and R. pseudopunctatum, the First Mosses to Yield Flavone Glucuronides
Authors: Mues Rüdiger , Leidinger Gesine , Lauck Vera , Zinsmeister H. Dietmar , Koponen Timo , Markham Kenneth R. 
Published: August 2018

Abstract
Rhizomnium magnifolium and R. pseudopunctatum show an identical flavonoid pattern with six flavone glucuronides.
Three of them; namely apometzgerin 7-O-glucuronide, selgin 7,5′-di-O-glucuronide and tricetin 7,3′-di-O-glucuronide are new natural compounds. This is the first report of flavonoid glucuronides in mosses.
Isolation and Characterization of 3 Protochlorophyllides from Pigment Mutant C-2 A′ of Scenedesmus obliquus
Authors: Kotzabasis Kiriakos , Senger Horst 
Published: August 2018

Abstract
Three Protrochlorophyllides (protochlorophyllide) were separated from mutant C-2 A′ of the green alga Scenedesmus obliquus. They show distinct differences in polarity, absorption and fluorescence characteristics. Until further characteristics are established we have to assume that we found monovinyl protochlorophyllide (MV-protochlorophyllide), divinyl protochlorophyllide (DV-protochlorophyllide) and a third protochlorophyllide with different side groups. - The question whether these protochlorophyllides are intermediates in the same pathway or precursors of chlorophylls a, b and RC I in separate pathways remains open at this stage of investigation.
The Glio-Axonal Interaction and the Problem of Regeneration of Axons in the Central Nervous System — Concept and Perspectives
Authors: Wolburg Hartwig , Neuhaus Jochen 
Published: August 2018

Abstract
Lesion of the central nervous system in man is generally believed to be incurable. However, in the last time evidence accumulated that axonal growth occurs after a lesion if the growing neurites encounter a permissive environment. Since astrocytes play a considerable role as environmental factor in the CNS, the astrocytes from regenerative as well as from non-regenerative species were compared. The concept proposed here postulates that interactions between astrocytes and axons are of basic significance for fiber regeneration and have changed qualitatively during phylogeny: in lower vertebrates astrocytes guide growing and regenerating axons; in higher vertebrates including man the glioaxonal interactions were possibly deteriorated by the appearance of new compounds in the astrocytic membrane.
Characterization of Glutamine Synthetase of Roots, Etiolated Cotyledons and Green Leaves from Sinapis alba (L.)
Authors: Manderscheid Remigius , Wild Aloysius 
Published: August 2018

Abstract
Glutamine synthetase of roots, etiolated cotyledons and green leaves from mustard plants cannot all clearly be separated by DEAE-Sephacel chromatography. However, the enzyme of the roots, etiolated cotyledons and green leaves, respectively, differed in the kinetic properties deter­mined in the crude extract. The root enzyme showed a pH-optimum of about 6.9, a Km value of 3 mᴍ for glutamate and a temperature optimum at 48 °C. Glutamine synthetase of etiolated cotyledons possessed a Km for glutamate of 6 or 12 mᴍ, depending on the dithioerythritol con­centration in the homogenisation buffer and a temperature optimum at 46 °C. The enzyme of green leaves was characterized by a temperature optimum at 40 °C, a pH-optimum at about 7.4 and a low glutamate affinity with positive cooperative substrate binding. Based on isolation of chloroplasts and identification of glutamine synthetase the enzyme of green leaves seems to be the chloroplastic form. This enzyme was purified by DEAE-Sephacel, hydroxylapatite and Sephacryl S-300 chromatography. Affinity for glutamate and MgSO4 of the purified enzyme differed from that found in the crude extract. The function of the different isoenzymes is discussed.
Are Polyphosphoinositides Involved in Signal Transduction of Elicitor-Induced Phytoalexin Synthesis in Cultured Plant Cells ?
Authors: Strasser Heiner , Hoffmann Christina , Grisebach Hans , Matern Ulrich 
Published: August 2018

Abstract
The phospholipids of cultured parsley and soybean cells were labelled with myo-[2-3H]inositol, [2-3H]glycerol or [32P]orthophosphate. By one-and two-dimensional chromatographic comparison of the labelled phospholipids with reference substances, the presence of 1-(3-sn-phosphatidyl)-ᴅ-myo-inositol 4-phosphate and 1-(3-sn-phosphatidyl)-ᴅ-myo-inositol 4,5-bisphosphate was demonstrated in these cultures. These results were corroborated by analysis of the deacylation products. Cells were labelled with either myo-[2-3H]inositol, [2-3H]glycerol or [32P]orthophosphate and subsequently challenged with elicitor for various lengths of time. Radioactivity in individual phosphoinositides from these cells was determined. No significant influence of elicitor-challenge of either soybean or parsley cells on incorporation of 3H or 32P into polyphospho­inositides was found between 0.5 and 20 min after elicitor addition.
Effect of Tumour Regression on Serum and Tissue Copper Concentration in Mice Bearing Induced Fibrosarcoma
Authors: Chakravarty Prabir Kishore , Ghosh Aparesh , Chowdhury Jaysree Roy 
Published: August 2018

Abstract
Serum and tissue copper concentration was determined in mice bearing induced fibrosarcoma after successful chemotherapeutic treatment. The results showed a significant depression in copper concentration in the serum and tumour tissue after treatment with anti-cancer drugs. However, the liver copper concentration showed no significant change in treated groups of mice compared to before treatment.
Analysis of Single Channel Currents with a Microprocessor Based Device
Authors: Schreibmayer W. , Hofer E. , Wolf P. , Lueger A. , Tritthart H. A. 
Published: August 2018

Data evaluation of single channel currents obtained from artificial black lipid membranes and with the patch clamp method is an important part of every single channel study, but it is a time consuming part often exceeding the time for experimentation and recording by far.
We describe here a microprocessor based device, which allows the experimentator to analyse in a simple way the distribution of current levels in a single channel trace (amplitude-histogram analysis of single channel currents) either online, or offline.
Current levels are sampled at a constant frequency of 6 kHz and the relative frequencies of occurrence of these current levels are displayed as a histogram on the screen of an analog or digital storage oscilloscope.
The data reducing algorithm of this analyser eliminates the requirement of large amounts of mass storage that normally is needed for digital amplitude-histogram analysis of single channel recordings.
Examples of evaluation for both a voltage operated cation-channel and a blockage of a potas­sium channel by tetraethylammoniumchloride (TEA) are given.
Divergent Evolution of 5 S rRNA Genes in Methanococcus
Authors: Wich Günter , Sibold Lionel , Böck August 
Published: August 2018

Abstract
The organization of genes for 5S rRNA in the methanogenic archaebacterium Methanococcus (M .) voltae and their nucleotide sequences have been determined. M. voltae possesses three 5S rRNA genes, one of them is organized in an rRNA transcriptional unit coding for 16S-23S-5S rRNA. The other two are associated with seven tRNA genes in a putative transcriptional unit composed of 5′-tRNAThr-tRNAPro-tRNATyr-tRNALys - 5S rRNA-tRNAAsp-tRNALys - 5S rRNA-tRNAAsp-3′. Coding regions plus spacers of the tRNALys-5S rRNA-tRNAAsp block of this gene cluster occur twice with identical sequence. The 5S rRNA from this cluster displays considerable sequence divergence to the rRNA operon-linked 5S rRNA gene. Comparison of the M. voltae 5S rRNA sequences with those from M. vannielii revealed that the operon-linked genes on one hand and the tRNA-linked 5S genes on the other share a greater sequence homology than the two types of genes within each of the two organisms. This indicates an independent evolution of the two sets of 5S rRNA genes without selective pressure from other ribosomal components or, alternatively, lateral gene transfer.
E. coli Maltodextrin Phosphorylase: Primary Structure and Deletion Mapping of the C-Terminal Site
Authors: Palm D. , Goerl R. , Weidinger G. , Zeier R. , Fischer B. 
Published: August 2018

Abstract
The complete 796 residue amino acid sequence of maltodextrin phosphorylase was deduced from the E. coli malP nucleotide sequence. The calculated molecular weight of 90 500, including pyridoxal phosphate, is significantly larger than experimentally determined values. Enzymatically active and inactive mutants following deletion or exchange of up to 8 codons (7 amino acids) at the 3′ end (C-terminus) confirm the size of the mature native enzyme and disclose the essential functional or structural role of the highly conserved C-terminal region of phosphorylases.
Versuche zur Racematspaltung von Konduramin-Analogen durch enzymatische Umesterung in organischen Lösungsmitteln /Experiments on the Optical Resolution of Conduramine Analogs by Enzymatic Transesterification in Organic Solvents
Authors: Kresze Günter , Sabuni Mahmud 
Published: August 2018

Abstract
A series of 1-amino-2-cyclohexene-3-ols is subjected to an enzymatic transesterification by the system lipase on silica/tributyrin (Klibanov-method). Thereby, an optical resolution of 1r-benzoyl-amido-5t,6c-dimethoxy-1-cyclohexene-4c-ol is achieved. Advantages and disadvantages of this method are discussed.
Synthese von immobilisierten Peptidfragmenten an Polystyrol-Polyoxyethylen zur Affinitätschromatographie /Synthesis of Immobilized Peptide Fragments on Polystyrene-Polyoxyethylene for Affinity Chromatography
Authors: Bayer Ernst , Hellstern Heribert , Eckstein Heiner 
Published: August 2018

Abstract
Polystyrene-polyoxyethylene craft copolymers have been used for step-wise peptide synthesis. After completion of synthesis the protecting groups are cleaved under acidic conditions, where the polymer-peptide bond is stable. These gels in comparison to polystyrene peptide gels, show better properties for applications in affinity chromatography as well as synthesis on solid supports, because the advantageous properties of polystyrene beads are combined with the excellent spacer behavior of polyoxyethylene chains (mobility, solvation by water and organic solvents). Peptide gels with polylysine sequences have been synthesized as highly selective stationary phases for the separation of the homologous oligo desoxyribonucleotides (dT)n with n = 1-3. The principal possibilities of these gels for affinity chromatography is demonstrated.
Synthese und Bindungsverhalten eines künstlichen Rezeptors für biogene Amine /Synthesis and Complexing Features of an Artificial Receptor for Biogenic Amines
Authors: Schmidtchen Franz P. 
Published: August 2018

Abstract
The synthesis of a ditopic linear receptor 3 consisting of an azacrown ether moiety for binding prim, ammonium functions and a macrotricyclic tetrahedral moiety for binding hydrophobic guest species is described. The covalent interconnection of these subunits was supposed to constitute a receptor with enhanced specificity towards dopamine-type biogenic amines. Host-guest complexa­tion was studied in a competition method with potassium ion using ion selective electrodes. The binding features of 3 with a series of biogenic amines reveal that neither the absolute binding strength nor the selectivity is enhanced in relation to the monotopic receptor 4. It is concluded that 3 does not simultaneously utilize both receptor subunits in binding the biogenic amine substrates.
Biosynthesis of Vitexin and Isovitexin: Enzymatic Synthesis of the C-Glucosylflavones Vitexin and Isovitexin with an Enzyme Preparation from Fagopyrum esculentum M. Seedlings
Authors: Kerscher F. , Franz G. 
Published: August 2018

Abstract
A C-glucosyltransferase from Fagopyrum esculentum seedlings catalyzes the transfer of glucose from UDP-glucose or ADP-glucose to 2-hydroxyflavanones. In cell-free enzyme preparations it was shown that only 2-hydroxyflavanones, e.g. 2,4′,5,7-tetrahydroxyflavanone and 2,5,7-trihydroxyflavanone were appropriate substrates. Naringenin, naringenin-chalcone and the flavones apigenin and chrysin cannot act as glucosyl acceptors in C-glucosyl-flavonoid biosynthesis. This demonstrates that C-glucosylation occurs after oxidation of flavanones.
Chloride Availability Affects the Malate Content and its Control by the Circadian Clock in Pulvini of Phaseolus coccineus L
Authors: Mayer W.-E. , Rüge W.A. , Starrach N. , Hampp R. 
Published: August 2018

Abstract
In soil-grown 3-to 4-weeks-old Phaseolus coccineus L. plants the chloride content changed antagonistically in the extensor and flexor of the laminar pulvinus during the circadian leaf movement in continuous light. This is as expected for an osmoticum involved in the volume changes of pulvinar cells. H ow ever, the malate content of extensor and flexor cells was not altered in a circadian manner. Furthermore, during light/dark cycles the malate content in both, extensor and flexor, was higher in the light than in the dark. This indicates that malate was not used in the osmotic motor of leaf movement and that its level was not controlled by the circadian clock in 3-to 4-weeks-old soil-grown plants.
When leaves were cut from 14-days-old soil-grown plants and cultured in distilled water the pulvini were depleted of chloride and the malate content was increased. In these chloride de­ prived leaves malate, and to a lesser extent citrate (about 1/10 of malate), changed antagonistically in a circadian manner in the extensor and flexor, indicating that these organic anions were now involved in the osmotic motor and under the control of the circadian clock. The similar properties of pulvinar and stomatal movements of starch-containing guard-cells are evident: in both cases, depending on the availability of chloride, CL- and/or organic anions are used for the compensation of the electrical charge of K+.
Ringöffnungsreaktionen an bioreaktiven Lactamsystemen / Ring Opening Reactions of Bioreactive Lactam Systems
Authors: Frister Hermann , Schlimme Eckhard 
Published: August 2018

Abstract
1-β-ᴅ-Ribofuranosylpyrrolidin-2,5-dione (9) was synthesized by ribosylation of N-silylated succinimide (7) with 1,2,3,5-tetra-O-acetyl-β-ᴅ-ribofuranose in acetonitril in the presence of tin tetrachloride. The compounds 9, 1-β-ᴅ-ribofuranosyl-l-H-pyrrol-2,5-dione (5) and N-methyl- maleinimide (2) were converted with ammonia to the ring-opened components 16. 14 and 15. The bioreactivity of the N-maleinimide derivatives 2 and 5 with respect to addition and ring-opening reactions with amino acid side chains containing either thiol or amino groups was shown in model reactions with glutathion (compds. 17,18) and lysine (compds. 19, 20). The ring opening reaction of 3-methyl-3-phenyl-1-β-ᴅ-ribofuranosylpyrrolidin-2,5-dione (11) with lysine yields 21, thus demonstrating the possibility of glycosuccinylation of amino groups in proteins.
Inhibition and Photoaffinity Labeling of Photosystem II by Thiazolyliden-ketonitriles
Authors: Bühmann U. , Herrmann E. C. , Kötter C. 
Published: August 2018

A new group of photosynthetic inhibitors is described. Thiazolyliden-ketonitriles are blocking electron flow at the acceptor side of photosystem II. They displace radioactive metribuzin from the membrane. Functional properties indicate that the new inhibitors share the binding site on the herbicide binding protein D-1 identical to that of the classical triazinone/urea-type inhibitors. However, fine details in the functional inhibition pattern, like lag in the inhibition and no loss of activity in tris-treated membranes, group them more specifically among the phenol-type family of photosystem II inhibitors. By photoaffinity labeling and immunoblotting it is shown that an azido- derivative of the thiazolyliden-ketonitriles tags the 32 kDa polypeptide subunit of photosystem II. This shows that also the phenol group inhibitors interact with the D-1 protein.
MO calculations show that the predominant tautomeric form of the new ketonitrile inhibitors when bound to the membrane is the hydroxy-form, whereas cyanoacrylates with a comparable essential element are bound in the keto-form. As the first is a phenol-type, the second an urea- type inhibitor, this allows to define more clearly the essential chemical element in the phenol-type inhibitors responsible for effective binding to the D-1 protein, probably oriented in the binding niche towards histidine 215, rather than towards serine 264, as triazine/urea and the cyanoacrylate derivatives do.
Cytogenetic Effects of the Insecticide Methamidophos in Mouse Bone Marrow and Cultured Mouse Spleen Cells*
Authors: Amer Soheir M. , Sayed Magdy A. 
Published: August 2018

Abstract
The cytogenetic effect of the insecticide methamidophos (0,S-dimethylphosphoroamidothiolate) was studied in mouse bone marrow and mouse spleen cells in culture. In vivo the ability of methamidophos to induce micronuclei and sisterchromatid exchange in mouse bone marrow was investigated. In vitro mouse spleen cells in culture were used to assess the ability of the insecticide to induce chromosomal aberrations and sister chromatid exchange.
Three different routes of application for the pure insecticide were tested so as to cover the different possibilities for human exposure to the insecticide. Intraperitoneal, oral and dermal treatment with metham idophos caused toxicity to marrow as indicated bv a significant increase in the percentage of polychromatic erythrocytes (PEs) over that of the control.
Methamidophos showed mutagenic potential as evidenced by a positive response in the micronucleus and chromosomal aberrations assays. Thus, single and multiple i.p. injections at 6 and 4.5 mg methamidophos/kg body w t., oral administration of the insecticide for 14 consecutive days at a dietary level of 100 ppm and multiple dermal treatments (total 4) with 24 mg/kg body wt. induced a statistically significant increase in the frequency of PEs with micronuclei in mouse bone marrow. Moreover, the tested concentrations of m etham idophos as low as 0.25 ng/ml induced a high percentage of metaphases with chromosomal aberrations in cultured mouse spleen cells.
Methamidophos is a weak inducer of SCEs in mouse bone marrow and cultured mouse spleen cells.
Alkaloids in Stem Roots of Nicotiana tabacum and Spartium junceum Transformed by Agrobacterium rhizogenes
Authors: Wink Michael , Witte Ludger 
Published: August 2018

Abstract
The growth of root hairs from stems of Nicotiana tabacum and Spartium junceum was induced by Agrobacterium rhizogenes. Stem roots of Nicotiana contained nicotine and a second alkaloid, probably anabasein. Root hairs from stems of Spartium contained cytisine, N methylcytisine and anagyrine as major alkaloids. The alkaloid content of the tumors was 3-12 times higher than that of the respective healthy host tissue.
Flavonoids from the Leaf Resin of Snakeweed, Gutierrezia sarothrae
Authors: Hradetzky Dagmar , Wollenweber Eckhard , Roitman James N. 
Published: August 2018

Abstract
The resinous material excreted by aerial parts of snakeweed, Gutierrezia sarothrae, was analyzed for flavonoid aglycones. Six major flavonoids were characterized by their spectral data; nine minor flavonoids were identified by direct comparisons with markers. The major flavones form three pairs of isomeric products, five of which are 6,8-methoxylated.