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1Author    BenjaminF. Matthews, JackM W IdholmRequires cookie*
 Title    Expression of Aspartokinase, Dihydrodipicolinic Acid Synthase and Homoserine Dehydrogenase During Growth of Carrot Cell Suspension Cultures on Lysine-and Threonine-Supplemented Media  
 Abstract    Reduction in the amounts o f activity o f the first enzyme, aspartokinase (EC and two branch-point enzymes, dihydrodipicolinic acid synthase (EC and homoserine dehydrogen­ ase (EC, located in the pathway for the synthesis o f aspartate-fam ily am ino acids, oc­ curred when cell suspension cultures of Daucus carota L. var. Danvers were grown in media contain­ ing 2 m M threonine or 2 m M lysine, endproducts of the pathway. Activity o f the lysine-sensitive form of aspartokinase was decreased when cells were grown in medium containing lysine and the ac­ tivity of the threonine-sensitive form was decreased when cells were grown in m edium containing threonine. Activity o f the branch-point enzyme leading to threonine synthesis, hom oserine dehy­ drogenase, was decreased up to 70% in specific activity (units/m g protein) and relative activity (units/g fresh weight) when cells were grown in m edia containing lysine or threonine. Threonine had no effect on the relative activity of dihydrodipicolinic acid synthase, but decreased its specific activity. Lysine decreased the relative activity of the synthase by up to 40%, but had little effect on its specific activity. The decreased activities o f the enzymes were apparently not due to binding of the inhibitory amino acids to the enzymes since homogenization of cells in buffer with 2 m M lysi­ ne and threonine did not decrease the m easurable enzyme activities. These and other results pres­ ented suggest that both forms of the aspartokinase activity and homoserine dehydrogenase activi­ ty can be altered by supplementing the growth medium with lysine or threonine. 
  Reference    Z. Naturforsch. 34c, 1177—1185 (1979); received June 18 1979 
  Published    1979 
  Keywords    Daucus carota, Suspension Cultures, Amino Acids, Enzyme Regulation 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-1177.pdf 
 Identifier    ZNC-1979-34c-1177 
 Volume    34 
2Author    Bernd Knoop, R. Olf BeiderbeckRequires cookie*
 Title    Adsorbenskultur — ein W eg zur Steigerung der Sekundärstoffproduktion in pflanzlichen Suspensionskulturen Adsorbent Culture -M ethod for the Enhanced Production of Secondary Substances in Plant Suspension Cultures  
 Abstract    A crown-gall suspension o f M atricaria cham omilla L. was cultivated in the presence o f an adsorbent (activated charcoal, AC). The culture produces besides other secondary products coniferyl aldehyde which is excreted by the cells and distributed between cells, m edium , and the AC according to equilibrium distributions with more than 95% o f the substance adsorbed to the AC. This deprivation o f coniferyl aldehyde from the m edium enables the cells to increase the production o f this substance up to 60-fold. The system M atricaria/coniferyl aldehyde serves as a model for the improvement o f the production o f secondary products by means o f plant cell suspensions. 
  Reference    Z. Naturforsch. 38c, 484 (1983); received February 10 1983 
  Published    1983 
  Keywords    Matricaria, Suspension Culture, Coniferyl Aldehyde, Accumulation, Adsorbent 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0484_n.pdf 
 Identifier    ZNC-1983-38c-0484_n 
 Volume    38 
3Author    Yüko Yamashita, Hiroshi AshiharaRequires cookie*
 Title    Characterization of Hexokinase and Fructokinase from Suspension-Cultured Catharanthus roseus Cells  
 Abstract    Two different hexose-phosphorylating enzymes, hexokinase and fructokinase, were partially purified from suspension-cultured Catharanthus roseus cells. One of the enzymes, hexokinase, catalyzed the phosphorylation of both glucose and fructose. The K m values for glucose and fructose were 0.06 mM and 0.23 mM, respectively. The V max of the enzyme with fructose was approximately three times higher than with glucose. This enzyme was specific in its requirement for ATP and its K m value for ATP was 52 (ÍM. The optimum pH was 8.0 and Mg :+ or Mn :+ was required for the activity. The activity was inhibited by considerably higher concentrations of ADP (i.e., 4 mM ADP was required for 50% inhibition). The second enzyme, fructokinase, was specific for fructose, and no activity was detected with glucose as substrate. This enzyme used UTP or CTP as phosphate donor. The K m values of this enzyme for fructose and UTP were 0.13 mM and 0.15 mM, respectively. The pH optimum was 7.2, and Mg 2+ or Mn 2+ was required for the activity. These divalent cations could be partially replaced by Ca 2+ . The activity was inhibited non-competitively by ADP and AMP. 90% inhibition of the activity by 0.5 mM ADP was observed in the presence of 2 mM UTP and 5 mM MgCl 2 . Fructose-2,6-bisphosphate, glucose-1,6-bisphos-phate, glucose-6-phosphate, and fructose-6-phosphate had little or no effect on the activity of both the hexokinase and the fructokinase. Based on these results, a discussion is presented of the role of hexokinase and fructokinase and their involvement in the regulation of the metabolism of sugars in Catharanthus cells. 
  Reference    Z. Naturforsch. 43c, 827—834 (1988); received June 28 1988 
  Published    1988 
  Keywords    Catharanthus roseus, Suspension Culture, Fructokinase, Glycolysis, Hexokinase 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0827.pdf 
 Identifier    ZNC-1988-43c-0827 
 Volume    43 
4Author    Koshi Saito, Etuko Daimon, Kazuhito Kusaka, Sachio Wakayama, Yoshihiro SekinoRequires cookie*
 Title    Accumulation of a Novel Red Pigment in Cell Suspension Cultures of Floral Meristem Tissues from Carthamus tinctorius L  
 Abstract    A cell strain originally derived from floral meristem tissues of Carthamus tinctorius (dyer's saffron) produced substantial amounts of a novel red pigment under controlled culture conditions. The pigment isolated from alcoholic extracts of C. tinctorius cultures was compared with authentic carthamin, anthocyanins, betain, and carotenoids. It differed markedly from carthamin and showed none of the characteristic properties of the glycoside or chloride forms of authentic delphinidin, cyanidin, and pelargonidin. Analytic data indicated that this pigment also differs from betanin and from a-and ß-carotene. The name "Kurenamin" was tentatively given to this newly isolated red pigment. Effect of the culture media, micro-elements, macro-elements, and putative substrates on the kurenamin production were investigated during cell suspension culture. 
  Reference    Z. Naturforsch. 43c, 862—870 (1988); received September 2 1988 
  Published    1988 
  Keywords    Carthamus tinctorius, Pigment Accumulation, Suspension Culture 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0862.pdf 
 Identifier    ZNC-1988-43c-0862 
 Volume    43 
5Author    Hiroshi Hirano, M. Asaaki Sakuta, Atsushi Kom, Am IneRequires cookie*
 Title    Inhibition by Cytokinin of the Accumulation of Betacyanin in Suspension Cultures of Phytolacca americana  
 Abstract    The accumulation o f betacyanin was reduced by the addition o f various cytokinins to sus­ pension cultures o f Phytolacca americana. The decrease in the accumulation o f betacyanin was overcome by exogenously supplied tyrosine which is a precursor o f betacyanin. Benzylamino-purine (BAP) decreased the level o f free tyrosine in the cells. Feeding experiments using labeled tyrosine revealed that BAP reduced the incorporation o f labeled tyrosine into betacyanins (to about 50% o f the control rate). These results suggest that both the availability o f tyrosine and the biosynthetic activity o f the pathway from tyrosine to the betacyanins are involved in the inhibition o f the accumulation o f betacyanins by cytokinins in P hytolacca americana cells. 
  Reference    Z. Naturforsch. 47c, 705 (1992); received June 29/A ugust 17 1992 
  Published    1992 
  Keywords    Betacyanin, Cytokinin, Phytolacca americana, Suspension Culture, Tyrosine 
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 TEI-XML for    default:Reihe_C/47/ZNC-1992-47c-0705.pdf 
 Identifier    ZNC-1992-47c-0705 
 Volume    47 
6Author    Ingolf Richter, NikolausW. Eber, HelmutK. Mangold, K. Um, D. M. UkherjeeRequires cookie*
 Title    Incorporation o f P ositional Isom ers of cis-and /n z « 5-O ctadecenoic A cids into the Acyl Lipids o f Cultured Soya Cells  
 Abstract    Cell suspension cultures of soya were incubated with m -[ l -14C] octadecenoic acids and irans-[l-14C]octadecenoic acids, each of known composition with regard to positional isomers. Each of the positional isomers ranging from A 8-to A 15-cj's-octadecenoic acids and A l-to A 16-£r<ms-octadecenoic acids was readily incorporated into the acyl lipids of the cells, yet, the A9-cis-and the zJ9-*r<ms-isomers were the pre­ ferred substrates, cis-trans Isomerization did not occur during the incorporation of the fatty acids into the acyl lipids. 
  Reference    Z. Naturforsch. 33c, 303 (1978); received January 27 1978 
  Published    1978 
  Keywords    Isomeric Octadecenoic Acids, Acyl Lipids, Soya Cells, Suspension Cultures 
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 TEI-XML for    default:Reihe_C/33/ZNC-1978-33c-0303_n.pdf 
 Identifier    ZNC-1978-33c-0303_n 
 Volume    33 
7Author    Jochen Berlin, Ludger WitteRequires cookie*
 Title    Effects of Glyphosate on Shikimic Acid Accumulation in Tobacco Cell Cultures with Low and High Yields of Cinnamoyl Putrescines  
 Abstract    To study the flow of carbon through the shikimate pathway in tobacco cell cultures with low and high yields o f cinnamoyl putrescines, the cell cultures were treated with glyphosate. In the presence o f glyphosate the levels o f free shikimic acid were increased more than 300-fold by both cell lines. Despite of a normally 10-fold higher level o f cinnamoyl putrescines, the high yielding cell line accumulated only 25% more free shikimic acid than the low yielding cell line. This result together with earlier observations indicated that the increased formation o f cinnamoyl putrescines was rather limited by the activity o f phenylalanine ammonia lyase than by increased substrate supply caused by alterations in the shikimate pathway. 
  Reference    Z. Naturforsch. 36c, 210 (1981); received November 27 1980 
  Published    1981 
  Keywords    Nicotiana tabacum, Suspension Cultures, Shikimic Acid, Cinnamoyl Putrescines, Glyphosate 
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 TEI-XML for    default:Reihe_C/36/ZNC-1981-36c-0210.pdf 
 Identifier    ZNC-1981-36c-0210 
 Volume    36 
8Author    Jochen Berlin, Edgar Forche, Victor Wray, Joachim Hammer, Wolfgang HöselRequires cookie*
 Title    Formation of Benzophenanthridine Alkaloids by Suspension Cultures o f Eschscholtzia californica  
 Abstract    Suspension cultures of Eschscholtzia californica accum ulate the dihydro forms o f the benzo­ phenanthridine alkaloids sanguinarine, chelirubine, macarpine and chelerythrine, all o f which are known to be constituents o f the Eschscholtzia plant. U nder most experimental conditions dihydrochelirubine was found to be the main constituent of the cultured cells. The specific yields of alkaloids varied from zero to 1.7% on a dry weight basis depending on the m edia conditions. The highest specific yield was 1.5 m g/g dry weight or 13 mg/1 with the growth m edium B5. After transfer of the cells into the induction medium IM2 the alkaloid accum ulation increased to 17 mg/g dry weight and 146 mg/1. The induction m edium contained increased levels o f sucrose, decreased levels of phosphate and was devoid of phytohormones. The effect o f the various m edia conditions on the biosynthesis of phenolics was quite different to those found for the alkaloids. 
  Reference    Z. Naturforsch. 38c, 346 (1983); received February 7 1983 
  Published    1983 
  Keywords    Eschscholtzia californica, Suspension Cultures, Benzophenanthridine Alkaloids, Phenolics, Media Effects 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0346.pdf 
 Identifier    ZNC-1983-38c-0346 
 Volume    38 
9Author    Jochen Berhn, Brigitte VollmerRequires cookie*
 Title    Effects of a-Aminooxy-ß-phenylpropionic Acid on Phenylalanine Metabolism in /r-Fluorophenylalanine Sensitive and Resistant Tobacco Cells  
  Reference    Z. Naturforsch. 34c, 770 (1979); received May 18 1979 
  Published    1979 
  Keywords    Nicotiana tabacum, Suspension Cultures, a-A m inooxy-ß-phenylpropionic Acid, Chorismate Mu-tase, Phenylalanine, Pool Sizes 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0770.pdf 
 Identifier    ZNC-1979-34c-0770 
 Volume    34 
10Author    Jonathan GresselRequires cookie*
 Title    A Review of the Place of in vitro Cell Culture Systems in Studies of Action, Metabolism and Resistance of Biocides Affecting Photosynthesis  
 Abstract    The hom ogeneity, density and axenic nature of cell culture system s have made them an am e­ nable tool for studying many aspects of biocide research; screening, m etabolism , m ode of action and resistance. Cell cultures are "m ulti-hom ogeneous" and each hom ogeneous state may be analog­ ous to different plant parts. Cultures can be hom ogeneously green, hom ogeneously w hite in either a hom ogeneously exponential or stationary phase of growth. Exam ples are be presented showing why no sin gle hom ogeneous state should be envisaged to be analogous to a whole plant in biocide studies. Because of the possibility of more uniform herbicide application, culture systems have a use in isolatin g resistant crop strains, at higher selection pressures and much higher "p lan t" densities than is possib le in the field, with recent successes. Protoplast fusion techniques may allow the transfer of gen etic resistance between related but genetically incom patible crop species. 
  Reference    Z. Naturforsch. 34c, 905—913 (1979); received M ay 24 1979 
  Published    1979 
  Keywords    Callus Cultures, Suspension Cultures, H erbicide Action, H erbicide M etabolism, H erbicide R esistance 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0905.pdf 
 Identifier    ZNC-1979-34c-0905 
 Volume    34 
11Author    W. N. Oé, H. U. SeitzRequires cookie*
 Title    Studies on the Regulatory Role of fra/is-Cinnamic Acid on the Activity of the Phenylalanine Ammonia-Lyase (PAL) in Suspension Cultures of Daucus carota L  
 Abstract    In vivo and in vitro experiments were performed in order to study the regulatory role of trans-cinnamic acid and its hydroxylated derivatives (p-coumaric acid, caffeic acid) on the deamina­ tion of phenylalanine catalyzed by PAL (EC 7>arts-cinnamic acid inhibits growth and reduces the content of soluble proteins of anthocyanin-containing carrot cells grown in suspen­ sion. There is strong evidence from the polysomal patterns and from the effect of ?ra«5-cinnamic acid on protein synthesis in vitro that protein synthesis is inhibited. The kinetic data of PAL clearly demonstrate that /ra«s-cinnamic acid inhibits the enzyme by a noncompetitive mecha­ nism. On the contrary, L-a-aminooxy-/?-phenylpropionic acid (l-AOPP), a competitive inhibitor of PAL, does not affect protein metabolism. 
  Reference    Z. Naturforsch. 38c, 408 (1983); received January 24 1983 
  Published    1983 
  Keywords    Phenylalanine Ammonia-Lyase, Protein Metabolism, Regulation, /ra/js-Cinnamic Acid, Daucus carota, Suspension Culture 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0408.pdf 
 Identifier    ZNC-1983-38c-0408 
 Volume    38 
12Author    Kaoru Kubota, Xiao-Ni Li1, Hiroshi AshiharaRequires cookie*
 Title    The Short-Term Effects of Inorganic Phosphate on the Levels of Metabolites in Suspension-Cultured Catharanthus roseus Cells  
 Abstract    In order to analyze the effects o f inorganic phosphate (Pi) on the energy metabolism o f suspen­ sion-cultured cells o f Catharanthus roseus, short-term changes in levels o f glycolytic m etabolites were m onitored after the addition o f 1.25 mM Pi to cultures of cells previously cultured in a Pi-free M urashige-Skoog m edium for 24 h. The levels o f all phosphorylated interm ediates o f glycolysis exam ined were found to increase after addition o f Pi. The most striking increases were observed in levels o f glucose-6-phosphate and fructose-6-phosphate which rose to approximately 8 (after 30 min) and 15 tim es (after 120 min) their initial values. The levels o f A TP and pyrophosphate doubled during the first 30 min o f incubation. In contrast, the level of pyruvate decreased signifi­ cantly during the initial 30 min and then began to increase again for the next 90 min. The short­ term effects o f Pi on the rates o f synthesis o f proteins and R N A were estim ated from the rates o f incorporation o f 14C-labelled am ino acids and uridine into the macrom olecules. No appreciable stim ulation o f the synthesis o f proteins and R N A was induced by Pi within 120 min after the addition o f Pi. Possible m echanism s are discussed that may be involved in the changes in m etab o­ lism initiated by the addition o f Pi to the cultures. 
  Reference    Z. Naturforsch. 44c, 802—806 (1989); received June 5 1989 
  Published    1989 
  Keywords    Catharanthus roseus, Suspension Culture, Inorganic Phosphate, G lycolytic M etabolites, M etabolic Regulation 
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 TEI-XML for    default:Reihe_C/44/ZNC-1989-44c-0802.pdf 
 Identifier    ZNC-1989-44c-0802 
 Volume    44