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1991 (171)
41Author    M. T. Òth, G. SzöcsRequires cookie*
 Title    Epoxyheptadecadienes Identified as Sex Pheromone Components of Tephrina arenacearia Hbn. (Lepidoptera: Geometridae)  
 Abstract    R esearch In stitu te for P lan t P ro tectio n o f the H u n g arian A cadem y o f Sciences, P f 102, H-1525 B udapest, H u n g ary C. Löfstedt, B. S. H ansson 
  Reference    Z. Naturforsch. 46c, 257 (1991) 
  Published    1991 
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 Identifier    ZNC-1991-46c-0257 
 Volume    46 
42Author    J. R. Aldrich, J. P. Kochansky, W. R. LusbyRequires cookie*
 Title    Pheromone Blends of Predaceous Bugs (Heteroptera: Pentatomidae: Podisus spp.)  
  Reference    Z. Naturforsch. 46c, 264 (1991) 
  Published    1991 
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 Identifier    ZNC-1991-46c-0264 
 Volume    46 
43Author    Johanna Bodenstein, H. Artm, Ut FollmannRequires cookie*
 Title    Characterization of Two Thioredoxins in Pig Heart Including a New Mitochondrial Protein  
 Abstract    Biologie/Chem ie der U niversität K assel, Biochemie, H ein rich -P lett-S traß e 40, D-3500 K assel, B undesrepublik D eutschland Z. N atu rfo rsch . 46c, 2 7 0 -2 7 9 (1991); received N ovem ber 12. 1990 M alate D ehydrogenase, M ito ch o n d rial P roteins, R ibonucleotide R eductase, T hioredoxins H eart tissue co ntain s tw o different thioredoxins. O ne is a specific m ito ch o n d rial pro tein and is best prepared from pre-isolated, intact heart m ito ch o n d ria (m t-th io red o x in) w hereas m ito-chondria-dep leted tissue hom ogenates contain the m ajor cellular th io red o x in o f cytoplasm ic origin (c-thioredoxin). Both heat-stable proteins are clearly d ifferentiated c h ro m ato g rap h ical-ly. They exhibit slightly different m olecular w eights (12300 vs. 12000) an d isoelectric po in ts (4.7 vs. 4.8) b u t differ rem ark ab ly in their cysteine content: m t-T h io red o x in has tw o cysteine residues like the bacterial p roteins, and c-thioredoxin possesses six cysteines. H eart ex tracts were also show n to contain a N A D P H -specific thioredoxin reductase o f the know n m am m ali­ an type. A specific function o r target enzyme o f m t-thioredoxin has n o t as yet been established. 
  Reference    Z. Naturforsch. 46c, 270 (1991) 
  Published    1991 
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 Identifier    ZNC-1991-46c-0270 
 Volume    46 
44Author    E. Kleber, R. Kroner, E. F. ElstnerRequires cookie*
 Title    Cataract Induction by 1,2-Naphthoquinone I. Studies on the Redox Properties of Bovine Lens Proteins  
 Abstract    In stitu t für Botanik und M ikrobiologie, Biochem isches L ab o r, T echnische U niversität M ünchen. A rcisstraße 21, 8000 M ünchen, B undesrepublik D eutschland Z. N aturforsch . 46c, 2 8 0 -2 8 4 (1991); received O cto b er 25, 1990 C atara ct, N ap h th o q u in o n e, Redoxcycling, O xygen A ctivation C onditions o f oxidative stress m ay lead to cata ra c t fo rm atio n . R eaction o f certain flavopro-teins, the N A D H :oxidoreductases, w ith different qu in o n es is well know n to form hydrogen-peroxide. This reaction was investigated to get m ore in fo rm atio n on ca ta ra ct induction by naphthalene and its q uinone m etabolites. P rotein ex tracts from bovine lens cortex exhibit "d iap h o rase" activity, indicated as dye reduction in the presence o f N A D H and dichloro-phenol-indophenol (D C P IP) or ferricyanide. D ifferent redox cycling co m p o u n d s are show n to be active in this "d iap h o rase" reaction by lens p ro tein ex tract (LC E): Oxygen consum ption can be detected in the presence o f p y rro lo q u in o lin e q u in o n e and ju g lo n e w hereas 1,4 -n ap h th o ­ q uinone, m enadione an d p a ra q u a t are no redox cyclists in this flavoprotein catalyzed reaction. 
  Reference    Z. Naturforsch. 46c, 280 (1991) 
  Published    1991 
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 Identifier    ZNC-1991-46c-0280 
 Volume    46 
45Author    R. Kroner, E. Kleber, E. F. ElstnerRequires cookie*
 Title    Cataract Induction by 1,2-Naphthoquinone II. Mechanism of Hydrogenperoxide Formation and Inhibition by Iodide  
 Abstract    In stitu t für B otanik und M ikrobiologie, Biochemisches L abor, T echnische U niversität M ünchen, A rcisstraße 21, 8000 M ünchen 2, B undesrepublik D eutschland Z. N atu rfo rsch . 46c, 2 8 5 -2 9 0 (1991); received O ctober 25, 1990 C atara ct, 1,2-N aphth o q u in o n e, Iodide, H ydrogenperoxide, Sulfhydryl G ro u p s N ap h th alen e cata ra c t is p ro b ab ly due to peroxide p roduction th rough n ap h th o q u in o n e (N Q) redox cycling a n d /o r g lu tath io n e conjugation. Both m echanism s yield losses o f essential SH -groups in cristallins a n d are thus p robably involved in protein m odification finally visible as lens opacity. 1 ,2 -N ap h th o q u in o n e produces H 20 2 in the presence o f either ascorbate, glutathione, N A D H o r -to a lesser extend -by hom ogenates o f lens p rotein p rep aratio n s. In the presence o f 1,2-n a p h th o q u in o n e and the above reductive additio n s, b o th , oxygen u p tak e and H 20 : fo rm atio n can be observed. Reductive oxygen activation in these system s are dim in-uated by iodide in a co n cen tratio n -d ep en d en t m anner. Since m aleim ide-treated pro tein s are less capable to activate oxygen by 1,2-n ap h th o q u in o n e, a direct oxygen activ atio n by the in ter­ actions o f 1,2-naphth o q u in o ne w ith protein-S H is indicated. C atalysis o f "d ia p h o rase "-type (dia) enzym es via N A D H -dia -1,2-NQ -0 2 seems not to operate in hydrogenperoxide p ro d u ctio n during 1,2-n ap h th o q u in o n e lens toxicity. 
  Reference    Z. Naturforsch. 46c, 285 (1991) 
  Published    1991 
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 Identifier    ZNC-1991-46c-0285 
 Volume    46 
46Author    R. Lederhofer, J. Schnakenberg, H. StieveRequires cookie*
 Title    Stochastic Treatment of Bump Latency and Temporal Overlapping in Limulus Ventral Photoreceptors  
 Abstract    S eptem ber 4, 1990 Q uantum Bumps, L atency, F irst-P assage Tim e, L ight-E voked and S p ontaneous Bumps, Poisson Statistics o f P h o to n s We present q u an tu m bum ps o b tain ed from flash experim ents at the Limulus ventral nerve p ho to recep to r un d er voltage clam p con d itio n s. T he results are show n and discussed in form o f histogram s for the latency, am plitu d e and net charge tran sfer (current time integral) o f the bum p current responses. We argue th a t the experim ental latency histogram s can n o t be de­ scribed satisfactorily by chem ical m odels if one assum es th a t not m ore than one p h o to n is c ap ­ tured per flash. Instead of, one has to tak e into acco u n t the Poisson statistics o f the captures o f 0 ,1 ,2 ,... ph o to n s released by a single flash. W e show th a t the inclusion o f Poisson statistics makes the effective latency histogram s o f flash responses typically asym m etric and skewed to ­ w ards short latencies as co m p ared to th a t o f m odel histo g ram s for one-p h o to n responses. O u r conjecture also im plies th a t un d er o u r experim ental c o n d itio n s a fraction o f up to 20% o f the bum p responses evoked by a flash should be suspected to be superpositions o f tw o ore m ore one-photon responses w hich c an n o t be sep arated by any kind o f evaluation analysis. C onse­ quently, the average values o f am plitudes an d net charge transfers o f the light-evoked bum p responses are expected to be overestim ated as co m p ared to th a t o f true o n e-p h o to n responses. This hypothesis is confirm ed by a num erical sim ulation o f light-evoked bum p responses using experim entally recorded sp o n tan eo u s bum ps (at tim es larger th an 1 s after the flash) as the sim ulation m aterial. W e show th a t th e su p erp o sitio n o f o n e-p h o to n events in the light-evoked bum p responses due to Poisson statistics settles the q uestion why their am plitudes and net charge transfers are found to be larger th an th a t o f the sp o n tan eo u s bum ps. We suggest th at true one-photon responses evoked by a light flash an d sp o n tan eo u s bum ps start from the sam e activated rhodopsin state and take the sam e biochem ical pathw ay. 
  Reference    Z. Naturforsch. 46c, 291—3 (1991); received 
  Published    1991 
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 Identifier    ZNC-1991-46c-0291 
 Volume    46 
47Author    M. Assim, DiG. IulioRequires cookie*
 Title    On the Relationships between the Genetic Code Coevolution Hypothesis and the Physicochemical Hypothesis  
 Abstract    This paper analyzes the relationships between the genetic code coevolution hypothesis and the physicochemical hypothesis by means o f a comparative study o f the precursor-product amino acid pairs on which the former hypothesis is based. Even if the coevolution between the biosynthetic relationships o f amino acids and the organization o f the genetic code is not ques­ tioned in this paper, the results and the arguments used lead us to believe that the selective pressures considered essential by the physicochemical postulates, played a more active role than that o f the precursor-product relationships in defining the allocation o f these amino acids in the genetic code. It is furthermore pointed out that the two evolutionary hypothesis might be aspects o f the same selective pressure, and thus difficult to differentiate. 
  Reference    Z. Naturforsch. 46c, 305 (1991); received September 28 1990 
  Published    1991 
  Keywords    Genetic Code Theories, C oevolution, Precursor-Product Amino Acids, Am ino Acids Proper­ ties, Hypergeometric Distribution 
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 Identifier    ZNC-1991-46c-0305 
 Volume    46 
48Author    E. Ra, H.-DL. Üdem Ann, N., M. R.Requires cookie*
 Title    Temperature Dependence of the Rotational Mobility of the Sugar and Water Molecules in Concentrated Aqueous Trehalose and Sucrose Solutions  
 Abstract    Carbon-13 and deuteron spin lattice relaxation times T, o f concentrated solutions o f tre­ halose and sucrose in heavy water are given as function o f temperature. From the temperature dependence o f the Tx ideal glass transitions temperatures Ta are derived. For both compounds the T0 derived for the disaccharides are at high concentrations larger than the Ta o f the water molecules. 
  Reference    Z. Naturforsch. 46c, 313 (1991); received January 14 1991 
  Published    1991 
  Keywords    Disaccharides, Solutions, Mobility Glass Transition 
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 Identifier    ZNC-1991-46c-0313 
 Volume    46 
49Author    Z. NaturforschRequires cookie*
 Title    Bradyrhizobium japonicum nifA M utant  
 Abstract    Glycine, Hypersensitive R esponse, R adioim m uno­ assay, Symbiosis The mutation o f the nifA gene o f Brady rhizobium ja ­ ponicum leads to a pathogenic-like response o f the host plant. Soybean nodules induced by the nifA mutant A 9 exhibited sym ptom s o f a hypersensitive reaction (H R) normally observed in plant pathogen interac­ tions as localized death o f infected cells and the accu­ mulation o f the phytoalexin glyceollin I. Little or no glyceollin I was present in nodules elicited by wild type B. japonicum 1 I Ospc 4. 
  Reference    Z. Naturforsch. 46c, 318 (1991); received September 22/ N ovem ber 2 1990 
  Published    1991 
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 Identifier    ZNC-1991-46c-0318_n 
 Volume    46 
50Author    A. Lberto Chersi, M. Aria, C. Ristina, Rg An, Ti-K Ossm, Ann, M. Ichele, E. Vangelista, C. Ristina CenciarelliRequires cookie*
 Title    Partial Characterization o f anti-H L A C lass II Antibodies Isolated by Aid o f Sepharose-Peptide Immunoadsorbents  
 Abstract    Synthetic peptides selected from H L A -D Q and HLA-DP glycoproteins were coupled to Sepharose, and used for the isolation o f anti-H LA Class II antibodies from the immune sera o f rabbits immunized with human lym-phoblastoid cells expressing Class II antigens. Antibodies from early and late bleedings displayed re­ markable differences in affinity for peptides and for sol­ uble membrane proteins: these differences might be due to an early immune response directed preferentially against surface linear determinants, and to a late re­ sponse to assembled (discontinuous) sites. The possibility that such antibodies might be used for the identification o f amino acid stretches involved in the formation o f the same assembled determinant is consid­ ered. 
  Reference    Z. Naturforsch. 46c, 321 (1991); received September 10 1990 
  Published    1991 
  Keywords    Synthetic Peptides, Histocom patibility Antigens, anti-HLA Antibodies 
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 Identifier    ZNC-1991-46c-0321_n 
 Volume    46 
51Author    E. Ckhard, W. Ollenw EberRequires cookie*
 Title    New Frond Exudate Flavonoids from Cheilanthoid Ferns  
 Abstract    Cheilanthes argentea, Notholaena spp., Pityrogram ma triangularis, Platyzom a microphylla, Pteridaceae A series o f new flavonoid aglycones have been identified in the frond exudates o f the fern Cheilanthes argentea, in five species o f Notholaena, in Pityrogram ma triangularis, and in P laty­ zom a microphylla. These aglycones comprise several rare flavonoids and five novel natural products: 5,7,8-trihydroxy-3-methoxy-6-methyl flavone, 3,5,2'-trihydroxy-7,8,4'-trimethoxy flavone, 5,2'-dihydroxy-3,7,8-trim ethoxy flavone, 5,7,4'-trihydroxy-2'-methoxy flavanone, and 3,5,4'-trihydroxy-6,7,8-trimethoxy flavone. The novel flavonoids were characterized by their N M R spectral data. 
  Reference    Z. Naturforsch. 46c, 325 (1991); received February 7 1991 
  Published    1991 
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 Identifier    ZNC-1991-46c-0325 
 Volume    46 
52Author    M. Asaaki, M. Oriyam, SunaoO. Rihara, L. Ingham, Ju, K. Aw Ab Ata, M. IzutaniRequires cookie*
 Title    Naturally Occurring Coumaranochroman-4-ones: a New Class of Isoflavonoids from Lupins and Jamaican Dogwood  
 Abstract    A further investigation o f the isoflavonoid com ponents o f Piscidia erythrina, Lupinus alhus and L. luteus has revealed the presence o f 3-hydroxy-and 3-m ethoxy-coumaranochrom an-4-ones. These compounds are the first known representatives o f a new type o f naturally occur­ ring isoflavonoid. Using a combination o f chemical and spectroscopic methods, the com pounds were identified as 3,5,7,4'-tetrahydroxy-5'-methoxy-3'-(3,3-dimethylallyl)couma-ranochroman-4-one (piscerythrol, 1), 3,5,7,4'-tetrahydroxy-6,3'-di(3,3-dimethylallyl)couma-ranochrom an-4-one (lupinol A, 3), 5,7,4'-trihydroxy-3-methoxy-6,3'-di(3,3-dimethylallyl)-coum aranochrom an-4-one (lupinol B, 6) and 3,5,7,4'-tetrahydroxy-6-(3,3-dimethylallyl)-coum aranochrom an-4-one (lupinol C, 7). All four isoflavonoids were found to have the cis relative configuration at C-2/C-3. Possible biogenetic relationships between the coumarano-chrom an-4-ones and other isoflavonoids (isoflavones and coum aronochrom ones) found in Piscidia and Lupinus are briefly discussed. 
  Reference    Z. Naturforsch. 46c, 331 (1991); received February 28 1991 
  Published    1991 
  Keywords    Leguminosae, Lupinus, Piscidia erythrina, Isoflavonoids, Coumaranochroman-4-ones, Coum aronochrom ones 
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 Identifier    ZNC-1991-46c-0331 
 Volume    46 
53Author    Satoshi Tahara, JohnL. Ingham, Junya MizutaniRequires cookie*
 Title    Substrate Specificity in the Fungal Metabolism of Prenylated Flavonoids  
 Abstract    The prenylated flavonoids, topazolin [5,7,4'-trihydroxy-3-methoxy-6-(3,3-dimethylaIlyl)-flavone], piscerythrone [5,7,2',4'-tetrahydroxy-5'-methoxy-3'-(3,3-dimethylallyl)isoflavone] and piscidone [5,7,4',5'-tetrahydroxy-2'-methoxy-6'-(3,3-dimethylallyl)isoflavone] were meta­ bolized by Aspergillus flavus and Botrytis cinerea to give a variety of products. Topazolin and piscerythrone were converted by both fungi to com pounds similar to those previously ob­ tained from luteone (6-prenyl) and licoisoflavone A (3'-prenyl) respectively. The 6'-prenylated isoflavone piscidone was metabolized only by B. cinerea to give the corresponding dihydro-pyrano-isoflavone as a m ajor product. N either fungus was found to metabolize the 8-prenylated pyranoflavanonol lupinifolinol. 
  Reference    Z. Naturforsch. 46c, 341—348 (1991); received January 181991 
  Published    1991 
  Keywords    Prenylated Isoflavones, Flavone, Aspergillus fla m s, Botrytis cinerea, Fungal Metabolism, Piscidone, Piscerythrone, Topazolin 
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 Identifier    ZNC-1991-46c-0341 
 Volume    46 
54Author    YasuyukiH. Ashidoko, SatoshiT., D. JuRequires cookie*
 Title    Novel Bisabolanoids in Rosa rugosa Leaves  
 Abstract    Rosa rugosa, Sesquiterpene, Bisabolanoid Bisaborosaol A (1), a novel sesquiterpene belonging to the bisabolane class, was isolated from Rosa rugosa leaves. The absolute configuration o f 1 at C-4 was shown to be inverted in comparison with bisabolanoids from Compositae. Bisaborosaol A (1) and its corresponding carboxylic acid (2) may be biogenetically related to the carotanoids which constitute the major sesquiterpenes o f R. rugosa leaves. 
  Reference    Z. Naturforsch. 46c, 349 (1991); received June 5/October 10 1990 
  Published    1991 
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 Identifier    ZNC-1991-46c-0349 
 Volume    46 
55Author    Y. Asuyuki, H.Ash Id, SatoshiT., RikO. Iwaya, JunyaM. IzutaniRequires cookie*
 Title    Highly Oxygenated Bisabolanoids in Rosa rugosa Leaves  
 Abstract    Five novel bisabolane sesquiterpenes possessing a tetrahydrofuran ring or a hydroperoxy group were isolated from Rosa rugosa leaves and their structures elucidated by chemical and spectroscopic methods. These highly oxidized sesquiterpenes were structurally related to bisaborosaol A which is the major bisabolanoid o f the plant. 
  Reference    Z. Naturforsch. 46c, 357 (1991); received June 5/October 10 1990 
  Published    1991 
  Keywords    Rosa rugosa, Sesquiterpene, Bisabolanoid, Exoperoxide 
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 Identifier    ZNC-1991-46c-0357 
 Volume    46 
56Author    Michalis Simantiras, Eckhard LeistnerRequires cookie*
 Title    Cell Free Synthesis of ö-Succinylbenzoic Acid in Protein Extracts from Anthraquinone and Phylloquinone (Vitamin Producing Plant Cell Suspension Cultures. Occurrence of Intermediates between Isochorismic and ö-Succinylbenzoic Acid  
 Abstract    Rubiaceae, Galium spec., M orinda lucida, Biosynthesis, Isochorismic Acid Cell free protein extracts from heterotrophic anthraquinone (" R ubiatype") producing cell suspension cultures o f three different Galium species and from a photoautotrophic phylloqui­ none (vitamin K ,) producing cell suspension culture o f Morinda lucida Benth. (Rubiaceae) catalyzed the synthesis o f o-succinylbenzoic acid (OSB) from isochorism ic acid and a-oxoglutaric acid in the presence o f thiamine diphosphate and M n2+. At least two intermediates in the conversion o f isochorismic to o-succinylbenzoic acid were detectable. One o f these intermediates is likely to be identical to 2-succinyl-6-hydroxy-2,4-cyclohexadiene-l-carboxylate (SH CH C), a metabolite known to occur in bacterial mutants (m enD +) blocked in o-succinylbenzoic acid synthesis. The structure o f the second intermediate is as yet unknown. A third intermediate may also occur. 
  Reference    Z. Naturforsch. 46c, 364 (1991); received February 12/March 26 1991 
  Published    1991 
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 Identifier    ZNC-1991-46c-0364 
 Volume    46 
57Author    Elisabeth Häusler, Maike Petersen, AugustW. AlfermannRequires cookie*
 Title    Hydroxyphenylpyruvate Reductase from Cell Suspension Cultures of Coleus blumei Benth  
 Abstract    Cell suspension cultures o f Coleus blumei Benth. producing high amounts o f rosmarinic acid were used to study the biosynthetic pathway o f this caffeic acid ester. One o f the involved en­ zymes, the hydroxyphenylpyruvate reductase (H PPR), is characterized in this paper. HPPR catalyzes the N A D (P)H dependent reduction o f /^-hydroxyphenylpyruvate to /»-hydroxyphen-yllactate. The enzyme developed maximal activity at an incubation temperature o f 37 °C and at a pH o f 6.5 to 7.0. The reaction proceeded linearly for an incubation time o f 60 min and up to a protein concentration o f 0.2 mg per assay. As electron donor HPPR accepted N A D H and N A D P H with A^m-values o f 190 jim and 95 |im respectively. The enzyme reduced differently substituted hydroxyphenylpyruvates but not ß-phenylpyruvate. The apparent A^m-values for the various substrates were at 10 for /^-hydroxyphenylpyruvate, at 130^xm for 3,4-dihy-droxyphenylpyruvate and at 250 |iM for 3-methoxy-4-hydroxyphenylpyruvate. HPPR was com petitively inhibited by rosmarinic acid and pyruvate with /^-values o f 210 |iM and 200 |IM respectively. Caffeic acid,/>-coumaric acid and cinnamic acid did not affect the enzyme activity but/>-coumaroyl-CoA inhibited HPPR. 
  Reference    Z. Naturforsch. 46c, 371—3 (1991); received January 21 /February 26 1991 
  Published    1991 
  Keywords    Coleus blumei, Lamiaceae, Cell Suspension Culture, Biosynthesis, Rosmarinic Acid 
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 Identifier    ZNC-1991-46c-0371 
 Volume    46 
58Author    M. Argaret, F. Roberts, B. C. Homeyer, ThiD T PhamRequires cookie*
 Title    Further Studies of Sequestration of Alkaloids in Papaver somniferum L. Latex Vacuoles  
 Abstract    Papaver somniferum, Latex V acuoles, A lkaloid, Sequestration The uptake and sequestration o f alkaloids by latex vacuoles o f P. somniferum sedimenting at 900 x g and 1100 x g were studied; both populations take up morphine effectively. Morphine uptake by the 1100 x g vacuoles was stimulated by exogenous ATP and, after uptake o f large amounts o f alkaloid, both populations were stimulated by exogenous ATP to take up further morphine; this effect was no longer present in 900 x g vacuoles isolated from the latex o f more mature capsules. Uptake by 1100 x g vacuoles was more sensitive to temperature than that o f 900 x g vacuoles. Determination o f the proton gradient across the vacuolar membrane (ApH), controlled dissipation o f ApH through the use o f N H 4C1, and correlation with morphine up­ take demonstrated that morphine uptake was strongly dependant on the maintenance o f ApH. Inhibitors designed to produce loss o f protons from the vacuole had, however, little effect on the system. Nitrate, as an inhibitor o f tonoplast ATPase, had an inhibitory effect on morphine uptake by the 1100 x g vacuoles. U ptake o f meconate, [35S]sulphate and L-[Ul4C]malate, important acid constituents o f the 900 x g vacuoles was investigated. U ptake o f sulphate and malate was continuous and satura­ tion was not reached; the rate o f uptake o f sulphate and malate was much lower than that o f morphine and other alkaloids, and uptake o f m econate by these vacuoles was not detected. Studies on specificity o f alkaloid uptake with the 900 x g vacuoles indicated no absolute preference for either the (+)-or the (-)-iso m e r o f codeine. N oscapine uptake was stimulated by ATP under conditions where ATP had no effect on morphine uptake. Nicotine was not taken up, but low levels o f caffeine and l-m ethoxycanthin-6-one were taken up, but less effec­ tively than morphine or noscapine. Uptake o f alkaloids by P. somniferum latex vacuoles is dependant on the maintenance o f tonoplast ApH and an ATPase generates this ApH. Sequestration appears to involve protona­ tion and anion-cation stabilization involving meconate and sulphate. The specificity o f alka­ loid uptake suggested no clear correlation with pK or lipophilicity, and some sort o f channel mechanism, more related to alkaloid shape is suggested. 
  Reference    Z. Naturforsch. 46c, 377—3 (1991); received December 12 1990 
  Published    1991 
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 Identifier    ZNC-1991-46c-0377 
 Volume    46 
59Author    GeorgG. Gross, Klaus DenzelRequires cookie*
 Title    Biosynthesis of Gallotannins. ß-Glucogallin-Dependent Galloylation of 1,6-DigaIloylglucose to 1,2,6-Trigalloylglucose  
 Abstract    ß-Glucogallin (1-O-galloyl-ß-D-glucopyranose), 1,6-Di-O-galloyl-ß-D-glucopyranose, 1,2,6-Tri-O-galloyl-ß-D-glucopyranose, Galloyltransferase, Gallotannin Biosynthesis. Rhus typhina (sumach) An enzyme from leaves o f sumach (Rhus typhina) was partially purified that catalyzes the ß-glucogallin (l-O -galloylglucose)-dependent galloylation o f 1,6-digalloylglucose, thus form­ ing 1,2,6-trigalloylglucose and free glucose. This acyltransferase had a molecular weight o f ca. 750,000 and a pH optimum at 5 .0 -5 .5 . Besides ß-glucogallin (K m -3.9 mM), also related 1-O-phenylcarboxylglucoses acted as acyl donors. On the other hand, the acceptor substrate, 1,6-digalloylglucose (K m = 0.9 mM), could only be replaced by 1,6-diprotocatechuoylglucose (relative activity 46%); however, also tri-, tetra-, and pentagalloylglucoses were galloylated. A pronounced stimulation o f the enzymatic reaction was observed upon addition o f penta-or hexagalloylglucose into the assay mixtures. The systematic name " ß-glucogallin: 1,6-di-O-gal-loylglucose 2-O-galloyltransferase" (EC 2.3.1. —) is proposed for the enzyme. 
  Reference    Z. Naturforsch. 46c, 389—3 (1991); received February 5 1991 
  Published    1991 
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 Identifier    ZNC-1991-46c-0389 
 Volume    46 
60Author    Elisabeth Schwab, Peter Schreier, Irm Gard BendaRequires cookie*
 Title    Biotransformation of ß-Damascone by Botrytis cinerea  
 Abstract    Biotransformation o f ß-damascone (1) was studied with four strains o f B otrytis cinerea using grape must (A) and a mixture o f A with synthetic medium (B). Whereas in A 4-hydroxy-ß-dam ascone (2), 3-hydroxy-ß-damascone (3), and 2-hydroxy-ß-damascone (4) were found as volatile bioconversion products, in B additionally 4-oxo-ß-dam ascone (5) was detected. Fur­ thermore, 9-hydroxy-8,9-dihydro-ß-damascone (6) was identified as chemically formed by-product. Quantitatively, the results were strongly dependent on the strain and medium used. Incubation o f 1 with two B. c. strains in medium B led to an almost selective formation (93 and 95%) o f 2 and the highest yield o f products (30 and 66%). The bioconversion products were identified by capillary gas chromatography (H R G C) and coupled H R G C techniques, i.e. -mass spectrometry (H RG C-M S) and -Fourier transform infrared spectroscopy (H R G C -FTIR) after extractive sample preparation. 
  Reference    Z. Naturforsch. 46c, 395—3 (1991); received March 8 1991 
  Published    1991 
  Keywords    B otrytis cinerea, Coupled On-Line Capillary Gas Chromatographie Techniques, ß-D am ascone Biotransformation, Oxygenated ß-Dam ascones 
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 Identifier    ZNC-1991-46c-0395 
 Volume    46 
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