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Facet Publication Year 1980 [X]
Facet section ZfN Section C:Volume 035 [X]

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61	Author	H. H. Van Genderen, J. Van Schaik	Requires cookie*
	Title	Flavonoids and Related Compounds in Leaves of Pinaceae, IV
	Abstract	F lavonoids o f Cedrus deodara (R oxb.) G. D on ex Loud. Cedrus deodara, Pinaceae, Flavonoids Several flavonoids were isolated from needles of Cedrus deodara. Among them were the 3-glucosides o f kaem pferol, isorhamnetin and syringetin. Apigenin-7-glucoside and pre sumably an alkylkaempferol-3-diglucoside were also pres ent. Kaempferol-3-glucoside occurred both free and acyl-ated with /7-coumaric acid an d /o r ferulic acid.
	Reference	Z. Naturforsch. 35c, 342—343 (1980); received D ecember 28 1979
	Published	1980
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	Identifier	ZNC-1980-35c-0342_n
	Volume	35

62	Author	Manju Varma, R. S. Varma, M. R. Parthasarathy	Requires cookie*
	Title	Minor Phenolic Constituents of Grevillea robusta and Hakea saligna
	Abstract	Proteaceae, Grevillea robusta, Hakea saligna, Lignans Three hitherto unknown phenolic constituents epilyoni-resinol, its glucoside and rhamnocitrin-3-O-rutinoside have been isolated from G. robusta wood and leaves besides kaempferol-3-O-rutinoside whereas 2,6-dimethoxybenzo-quinone, lyoniresinol and its rhamnoside are obtained from H. saligna wood. Their structures were assigned on the basis of chemical and spectral evidence.
	Reference	Z. Naturforsch. 35c, 344—345 (1980); received November 15 1979
	Published	1980
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	Identifier	ZNC-1980-35c-0344_n
	Volume	35

63	Author	Rudolf Müller, Franz Lingens	Requires cookie*
	Title	Enzymatische Bildung und Isolierung von 2-Hydroxymuconsäure, ein M etabolit im bakteriellen Abbau des Herbizids Chloridazon Enzymatic Formation and Isolation of 2-Hydroxy- muconic Acid, a Metabolit in the Bacterial Degrada tion of the Herbicide Chloridazon
	Abstract	Chloridazon, Herbicide, Microbial D egradation, 2-Hy-droxymuconic Acid, meta-Cleavage 2-Hydroxymuconic acid, formerly postulated as an in term ediate of the bacterial degradation o f chloridazon (5-amino-4-chlor-2-phenyl-2H-pyridazin-3-on), could be iso lated after incubation of 5-amino-4-chlor-2-(2,3-dihydroxy-phenyl)-2 H-pyridazin-3-on (1) with purified metapyrocate-chase and enriched am idase from chloridazon-degrading bacteria by reversed phase high performance liquid chro matography.
	Reference	Z. Naturforsch. 35c, 346—347 (1980); eingegangen am 17. Dezem ber 1979
	Published	1980
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	Identifier	ZNC-1980-35c-0346_n
	Volume	35

64	Author	JuanC. Stockert, R. Paniagua	Requires cookie*
	Title	Ruthenium Red Staining of Chromatin in Epon Sections
	Abstract	Ruthenium Red, C hrom atin Staining After staining with a 50% ethanol solution o f ruthenium red, chrom atin from onion and mouse cells showed red color and high contrast in the light and electron m icro scope, respectively. When applied to glutaraldehyde-fixed, Epon-embedded tissues, this selective staining technique proved to be dependent on the DNA content o f chromatin.
	Reference	Z. Naturforsch. 35c, 348—349 (1980); received November 26 1979
	Published	1980
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	Identifier	ZNC-1980-35c-0348_n
	Volume	35

65	Author	AlanC. Cassells, RogerD. Long	Requires cookie*
	Title
	Abstract	Adventitious shoots regenerated from tobacco explants taken from donor-plants infected with cucum ber mosaic virus and potato virus Y, were virus infected. Sim ilar ex plants cultured in the presence o f Virazole were virus-free.
	Reference	Z. Naturforsch. 35c, 350—351 (1980); received January 7 1980
	Published	1980
	Keywords	PVY, CMV, Virazole, Tissue Culture
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	Identifier	ZNC-1980-35c-0350_n
	Volume	35

66	Author	Günter Pilwat, Peter Washausen, Joachim Klein, Ulrich Zimmermann	Requires cookie*
	Title	Immobilization of Human Red Blood Cells
	Abstract	H uman red blood cells were immobilized in an alginate network which was cross-linked with C a2+ ions. The im mobilized cells were stored for longer than 5 weeks at 4 °C in an isotonic buffered NaCl solution containing glucose, inosine, adenine, and guanosine for energy supply. The im mobilized cells were released from the alginate network by dissolving the matrix with citrate. Both the im mobilized and released cells retain their biconcave shape over the storage period. Measurements of the released cell popula tion in a hydrodynamically focussing Coulter C ounter demonstrated that the mean size of the size distribution, the breakdown voltage, and the internal conductivity have not changed in contrast to control m easurem ents on red blood cells stored conventionally in suspension indicating that im mobilization preserves cellular functions.
	Reference	Z. Naturforsch. 35c, 352—356 (1980); received December 4 1979
	Published	1980
	Keywords	Red Blood Cells, Immobilization, Reversible Gels, Electri cal Breakdown, Coulter Counter
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	Identifier	ZNC-1980-35c-0352_n
	Volume	35

67	Author	F.C M Driessens	Requires cookie*
	Title	Probable Phase Composition of the Mineral in Bone
	Abstract	Formulas proposed for the mineral of bone were reviewed. Literature data were collected where Ca, P, Na, Mg and C 0 3 are determined in the same samples. These data were analyzed for their conformity to the above mentioned formulas. According to this analysis Mg is contained in a phase having the Ca/P of magnesium whitlockite within the limits o f error. Na is contained in a carbonated calcium phosphate phase which in analogy with synthetic systems must have the apatite structure. The Ca/P ratio o f the remaining "rest phase" is 2. This is based on the composi tion of 101 bone mineral samples taken from fishes, reptiles, amphibians, birds and mammals. The C 0 3 content of the bone samples agrees with the formula Ca8 (P 0 4)4 (C 0 3) (OH)2 • x H20 for the "rest phase" within the limits of experimental error. Such a compound has, however, not been found in synthetic systems. Human bone contains about 15% magnesium whitlockite, 25% of the Na and C 0 3 containing apatite and the rest is the carbonated calcium phosphate with Ca/P = 2. It is presumed that this compound has a structure similar to that o f octo calcium phosphate and that most o f the citrate ions which always occur in bone mineral samples are in corporated in that phase.
	Reference	Z. Naturforsch. 35c, 357—362 (1980); received January 15 1980
	Published	1980
	Keywords	Bone, Mineral, Phase Composition, Citrate
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	Identifier	ZNC-1980-35c-0357
	Volume	35

68	Author	GeorgG. Gross, KarlJ. Koelen, Tropoyl Coenzyme, Thioester, N-Hydroxysuccinimide Tropoyl, Ester	Requires cookie*
	Title	Chemical Synthesis of Tropoyl Coenzyme A
	Abstract	Tropoyl coenzyme A has been synthesized in good yields via the corresponding N-hydroxysuc-cinimide ester. The UV-spectrum o f the purified thioester has an absorption maximum at 257 nm; at this wavelength, a molar extinction coefficient o f 19.2 x 106 [cm2 mol-1] has been determined. Upon alkaline hydrolysis o f the thioester bond a difference spectrum with Amax at 235 nm (zfe235= 4.8 x 106 [cm2 m ol-1]) has been observed. Attempts to prepare 2-phenylmalonyl coenzyme A by the same technique gave negative results.
	Reference	Z. Naturforsch. 35c, 363—366 (1980); received March 10 1980
	Published	1980
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	Identifier	ZNC-1980-35c-0363
	Volume	35

69	Author	Elisabeth Langer, H. Arald Lehner, Wolfhart Rüdiger, Barbara Zickendraht, -W Endelstadt	Requires cookie*
	Title	Circular Dichroism of C-Phycoerythrin: A Conformational Analysis
	Abstract	An extensive study o f the chiroptical properties o f C-phycoerythrin and the a-and ^-subunits in the spectral region from 700 -200 nm is presented. Based on the VIS-circular dichroism inherently chiral conform ations are proposed for the co valently linked chromophores. By means o f mean residue ellipticities and the experimental circular dichroism spectra in the region o f the n -* n* peptide transition the a-helix contents o f the apoproteins o f the ac-and ß-subunits are estimated to amount to 60% and 40%, respectively. The circular dichroism spectrum o f native C-phycoerythrin is congruent with a linear superposition o f the a-and /?-subspectra, in the whole spectral region studied. Since a-and /?-subunits are associated in native C-phycoery-thrin as revealed by sedim entation analysis the interactions between the subunits in the native chromoprotein are not accom panied by substantial conform ational changes. In the temperature range 0 ° -4 0 °C the thermally induced changes o f the chrom ophores in native C-phycoerythrin are not associated with changes o f the secondary structure o f the apoprotein. Unfolding occurs at 60 0 -7 0 °C but slowly leads to irreversible denaturation. Protein unfolding starts at 3 M urea. The random coil secondary structure o f the apoproteins is reached at 8 M urea. At this concentration the absorbance and the optical activity o f the chrom o phores are reduced by a factor 3 and 10, respectively. The conformational changes in the peptide with increasing denaturant concentration are not synchronous with those induced in the Chromo phore indicating that a m ultistep process is operative during unfolding. The C D results on dena turation are supplem ented by absorption and em ission spectroscopy.
	Reference	Z. Naturforsch. 35c, 367 (1980); received February 5 1980
	Published	1980
	Keywords	Phycoerythrin, Subunits, Conformation o f Chrom ophores and Apoproteins, Circular D ichroism, Denaturation
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	Identifier	ZNC-1980-35c-0367
	Volume	35

70	Author	O. Schmut, P. Roll, M. E. Reich, W. Palm	Requires cookie*
	Title	Biochemical and Electronmicroscopic Investigations on Helix pomatia Collagen A-8036 Graz, Austria
	Abstract	The skin o f Helix pomatia was investigated by biochemical methods and electronmicroscope. Biochemical investigations showed that Helix pomatia collagen represents a methionine-lacking collagen resistant to CNBr-cleavage. Electron microscopic studies showed a cross striation pattern of 5 3 -5 7 nm.
	Reference	Z. Naturforsch. 35c, 376—379 (1980); received February 4/24 1980
	Published	1980
	Keywords	Helix pomatia, Skin Collagen, Methionine, Electron Microscope
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	Identifier	ZNC-1980-35c-0376
	Volume	35

71	Author	EberhardG. Ehring, Hans Geiger	Requires cookie*
	Title	Die Flavonoide der Samen von
	Abstract	Medicago x varia Martyn c. v. Cardinal (Fabaceae) The Seed-Flavonoids o f Medicago x varia Martyn c. v. Cardinal (Fabaceae) Medicago x varia c. v., Fabaceae, Flavonoids, 5-Methoxyflavones, 5-Methoxyflavonols From the seeds of Medicago x varia Martyn c. v. Cardinal have been isolated twenty flavonoids, including four 5-methoxyflavonoids. Four compounds have been obtained the first time from a natural source. The constitution of all compounds is prooved.
	Reference	Z. Naturforsch. 35c, 380—383 (1980); eingegangen am 22. Januar 1980
	Published	1980
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	Identifier	ZNC-1980-35c-0380
	Volume	35

72	Author	JohnL. Ingham	Requires cookie*
	Title	Induced Isoflavonoids of Erythrina sandwicensis
	Abstract	Two new phytoalexins isolated from the fungus-inoculated leaflets of Erythrina sandwicensis have been identified as (—)-6aS; 11 aS-3,6 a,9-trihydroxy-10-isopentenylpterocarpan (sandwicar-pin) and (—)-6a/?; 11 a^-3-hydroxy-9-methoxy-10-isopentenylpterocaipan (sandwicensin). These compounds co-occur with several known pterocarpan (demethylmedicarpin, 3,6a,9-trihydroxy-pterocarpan, phaseollidin and cristacarpin) and isoflavan (demethylvestitol and isovestitol) deriva tives. The preparation and spectral (UV, MS) characteristics of 3-methoxy-9-hydroxy-10-isopen-tenylpterocarpan are also described.
	Reference	Z. Naturforsch. 35c, 384—386 (1980); received January 22 1980
	Published	1980
	Keywords	Leguminosae, Erythrina, Pterocarpans, Isoflavans, Phytoalexins
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	Identifier	ZNC-1980-35c-0384
	Volume	35

73	Author	Klaus Scheller, Hans-Peter Zim, Erm Ann, ConstantinE. Sekeris	Requires cookie*
	Title	Calliphorin, a Protein Involved in the Cuticle Formation of the Blowfly, Calliphora vicina
	Abstract	Injections of radioactively labelled calliphorin into Illrd instar larvae o f Calliphora indicate that the protein is incorporated into the integument. Immunofluorescence techniques show that the endocuticle is the Final site o f deposition o f calliphorin. It is concluded that calliphorin is an essen tial protein of the tanned cuticle.
	Reference	Z. Naturforsch. 35c, 387—389 (1980); received December 28 1979/February 14 1980
	Published	1980
	Keywords	Calliphorin, Insect Cuticle, Immunofluorescence, Calliphora vicina
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	Identifier	ZNC-1980-35c-0387
	Volume	35

74	Author	Ernst Priesner, Herm Ann Bogenschütz, Heinrich Am	Requires cookie*
	Title	A Sex Attractant for the European Fir Budworm Moth, Choristoneura murinana Forstliche Forschungs-und Versuchsanstalt Baden-Württemberg, D-7801 Stegen-Wittental bei Freiburg
	Reference	Z. Naturforsch. 35c, 390—398 (1980); received February 121980
	Published	1980
	Keywords	Pheromones, Sex Attractant, (Z)-9-dodecenyl Acetate, Olfactory Receptors, Choristoneura muri nana, Tortricidae
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	Identifier	ZNC-1980-35c-0390
	Volume	35

75	Author	Klaus-MichaelW. Eltring, W. Olfgang Barz	Requires cookie*
	Title	Degradation of 3,9-Dimethoxypterocarpan and Medicarpin by Fusarium proliferatum
	Abstract	The degradation o f 3,9-dimethoxypterocarpan was investigated in selected strains of Fusarium. Fusarium proliferatum (/'. e. Gibberella fujikuroi (SAW)WR) degrades this substrate via 3-meth-oxy-9-hydroxypterocarpan, 3,9-dihydroxypterocarpan and 2',4',7-trihydroxyisoflavan. During degradation by this organism medicarpin is first demethylated to 3,9-dihydroxypterocarpan.
	Reference	Z. Naturforsch. 35c, 399—405 (1980); received March 10 1980
	Published	1980
	Keywords	Phytoalexins, 3, 9-Dimethoxypterocarpan, Medicarpin, Fusarium, Degradation, Demethylation
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	Identifier	ZNC-1980-35c-0399
	Volume	35

76	Author	M.Arianne Nagel, ThomasH. Artm Ann	Requires cookie*
	Title	Glutamate Dehydrogenase from Medicago sativa L., Purification and Comparative Kinetic Studies of the Organ-Specific Multiple Forms
	Abstract	NAD-specific glutamate dehydrogenase [L-glutamate: N A D + oxidoreductase (deaminating) EC 1.4.1.2] from Medicago sativa constitutes organ-specific patterns o f isoenzymes. The isoenzyme-pattems o f seeds (GDH-I) and roots (GDH-II) were purified 1520-fold and 92-fold, respectively. All isoenzymes o f both patterns remain stable throughout the purification procedures. Isoenzyme a7, the only isoenzyme common to both patterns was isolated from the GDH-I pattern. The three enzyme preparations were found to be identical in pH optima, substrate specificity and general ki netic properties. A comparative kinetic analysis revealed no pronounced differences between the various kinetic constants evaluated for the three enzyme preparations. Furthermore an identical order of substrate binding and product release could be established. Both initial rate measure ments and product inhibition studies are consistent with an ordered ternary-binary kinetic mecha nism. The results suggest that tissue-specific enzyme multiplicity of plant glutamate dehydrogen ase is not related to differences in general or kinetic properties.
	Reference	Z. Naturforsch. 35c, 406 (1980); received January 71980
	Published	1980
	Keywords	Medicago sativa, Glutamate Dehydrogenase, Multiple Enzyme Forms, Purification, Kinetic Pro perties
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	Identifier	ZNC-1980-35c-0406
	Volume	35

77	Author	Joachim Vater, Thomas Gaudszun, Harald Schamow, Johann Salnikow	Requires cookie*
	Title	Competition of Pyridoxal 5'-Phosphate with Ribulose 1,5-Bisphosphate and Effector Sugar Phosphates at the Reaction Centers of the Spinach Ribulose 1,5-Bisphosphate Carboxylase/Oxygenase
	Abstract	Ribulose 1,5-Bisphosphate Carboxylase/Oxygenase, Effector Studies, Pyridoxal 5'-Phosphate Inhibition The Stimulation of the carboxylase reaction by effectors o f ribulose 1,5-bisphosphate carboxyl ase/oxygenase displays higher sensitivity towards pyridoxal 5'-phosphate inhibition than the catalytical process itself. Pyridoxal 5'-phosphate binding to the enzyme is not affected by the modulators 6-phospho-gluconate and fructose 1,6-bisphosphate at low concentrations at which these agents stimulate the carboxylation rate. At higher concentrations these sugar phosphates protect the enzyme against pyridoxal 5'-phos-phate inhibition in a similar fashion like the substrate ribulose 1,5-bisphosphate. Such protection experiments in combination with spectrophotometrical studies of pyridoxal 5'-phosphate binding demonstrate two binding states o f ribulose 1,5-bisphosphate at the reaction centers o f the enzyme with different requirements for Mg2+. 6-Phosphogluconate functions as protector only in the presence o f Mg2+. Our results imply a competition between pyridoxal 5'-phosphate and substrate or effector sugar phosphates at the reaction centers of the spinach carboxylase. It is proposed that the pyridoxal 5'-phosphate inhibition o f the stimulatory activity o f these effectors originates from a modification o f the regulatory sites o f the enzyme caused by pyridoxal 5'-phosphate binding to the catalytical sites.
	Reference	Z. Naturforsch. 35c, 416 (1980); received January 18/March 14 1980
	Published	1980
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	Identifier	ZNC-1980-35c-0416
	Volume	35

78	Author	Friedrich Kühlhorn, Ahlert Schmidt	Requires cookie*
	Title	Formation of Cyclic Adenosine-S'-S'-monophosphate (cAMP) from Adenosine-5'-phosphosulfate (APS) in Chlamydomonas reinhardtii CW 15?
	Abstract	Cyclic AMP, Adenosine-5'-phosphosulfate, Adenosine-5'-phosphoramidate, APS-Cyclase, Chlamydomonas reinhardtii Levels of cyclic adenosine monophosphate (cAMP) have been determined in the green alga Chlamydomonas reinhardtii strain CW 15. In the early exponential growth no cAMP was detected, however, in the middle o f the exponential growth phase 2.4 pmol cAMP/mg protein were found and the cAMP level increased to 18.8 pmol/mg protein in the stationary phase. An enzyme fraction has been isolated from Chlamydomonas, which produced cAMP in vitro using adenosine-5'-phosphosulfate (APS) as a substrate. This protein fraction was isolated by am-moniumsulfate precipitation, DEAE-cellulose chromatography and Sephadex-G-100 gel filtration. A solvent system was developed for thin layer chromatography to separate cAMP from APS, adenosine-5'-phosphoramidat (APN), 5'-AMP and adenosine. The product was identified as cAMP by cochromatography, coelectrophoresis, treatment with phosphodiesterase, chromato graphy on Biorad-columns and by the protein-binding assay. The so far purified protein fraction produced 151 pmol cAMP/mg protein and hour in vitro, using APS as a substrate.
	Reference	Z. Naturforsch. 35c, 423 (1980); received January 21 1980
	Published	1980
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	Identifier	ZNC-1980-35c-0423
	Volume	35

79	Author	Peter Dancker	Requires cookie*
	Title	Tropomyosin-Troponin-Induced Changes in the Partitioning of Free Energy Release of Actomyosin-Catalyzed ATP Hydrolysis as Measured by ATP-Phosphate Exchange
	Abstract	ATPase activity and ATP-Pj exchange o f unregulated (without tropomyosin-troponin) and regulated (with tropomyosin-troponin) acto-HMM were measured in media containing 0.2 mg/ml actin, HMM, and (when present) tropomyosin-troponin, 2 m M MgCl2, 10 m M KC1, 2 m M N aN 3, 10 m M Pi (pH 7.0), 3 mM ATP. The following mean values for ATPase activity and for the rate o f incorporation of P, into ATP (each per mg HMM and per min) were obtained: unregulated acto-HMM 0.33 \|imol Pj and 0.33 nmol Pi? regulated acto-HMM 0.54 nmol Pi and 1.06 nmol P*. The ratio o f P4 incorporation rate to ATPase activity was 1.01 x 10-3 for unregulated and 2.02 x 10-3 for regulated acto-HMM. From these ratios and from the overall free energy change o f ATP hydrolysis it was calculated that under the prevailing experimental conditions in unregulated acto-HMM 62% and in regulated acto-HMM 66% o f the free energy change o f ATP hydrolysis occurs after the release o f phosphate from actomyosin. It is probably this part of the free energy change that is used by the muscle for the performance o f work.
	Reference	Z. Naturforsch. 35c, 431—438 (1980); received November 19 1979/January 15 1980
	Published	1980
	Keywords	Actomyosin ATPase, ATP-Phosphate Exchange, Energy Transduction, Tropomyosin-Troponin, Muscle Contraction
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	Identifier	ZNC-1980-35c-0431
	Volume	35

80	Author	Eckhard Bast	Requires cookie*
	Title	Ammonia Assimilation by Thiocapsa roseopersicina Grown on Various Nitrogen and Carbon/Electron Sources
	Abstract	Batch cultures o f the phototrophic bacterium, Thiocapsa roseopersicina, were grown anaero bically in the light either on sulfide with various ammonia concentrations, N 2 or amino acids as nitrogen sources, or on several simple organic substrates in the absence o f reduced sulfur com pounds using 6 mM N H 4C1 as source o f nitrogen. At high ammonia concentrations high activities of (NADPH-linked) glutamate dehydrogenase (GDH), but rather low transferase and no bio synthetic activity of glutamine synthetase (GS) were obtained, while under conditions o f ammonia deficiency (growth with N 2 or glutamate) GDH activity was very low and both GS activities were strongly increased. Glutamate synthase (GOGAT) activity (NADH-dependent) showed little variation. These data indicate that at high NH+ concentrations ammonia is assimilated via GDH, under NHJ limitation, however, via the G S/G O G A T system. Glutamine as nitrogen source may be utilized via GOGAT as well as via an active glutaminase plus GDH. Ammonia, but not glutamine, seems to cause repression and inactivation of GS. Alanine and asparagine inactivate the enzyme inhibiting the biosynthetic, but not the transferase activity. These amino acids in part also influence the activities o f GDH, GOGAT, malate dehydrogenase (MDH) and isocitrate dehydro genase (ICDH). Cultures grown on acetate or pyruvate instead of sulfide showed increased GDH activities and high GS transferase activities possibly reflecting an increase o f intracellular a-ketoglutarate con centration. On malate or fructose also increased GS transferase activities, but rather low GDH activities were observed. High biosynthetic GS activities and elevated GOGAT activities were found only in fructose-grown cells. On the organic substrates the ICDH activities always were somewhat higher than after lithoautotrophic growth. With the exception of acetate, the MDH activities were considerably elevated, especially on pyruvate. The different pathways of ar-keto-glutarate formation and their influence on the enzymes of ammonia assimilation are discussed.
	Reference	Z. Naturforsch. 35c, 439 (1980); received December 17 1979
	Published	1980
	Keywords	Thiocapsa roseopersicina, Phototrophic Bacteria, Nitrogen Sources, Ammonia Assimilation, Carbon Metabolism
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	Identifier	ZNC-1980-35c-0439
	Volume	35

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