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1Author    H. B. Leising, D. 0. SdiadhtsdiabelRequires cookie*
 Title    Stimulation of Tyrosinase Activity and Melanin Formation of Cultured Melanoma Cells by Serum Deprivation Alone or in Combination with Dibutyryl Cyclic AMP and Theophylline  
 Abstract    Serum removal from the media of serial monolayer cultures of the Harding-Passey melanoma during an incubation period of 3 days resulted in an exponentially declining DNA synthesis rate (measured by the incorporation of [14C] thymidine) and in an inhibition of cell proliferation. Pro­ tein synthesis, as measured by the incorporation of radioactive leucine, was less affected than DNA synthesis. Incubation in serum-free culture medium resulted in significant rises of tyrosinase ac­ tivity and cellular melanin content. Addition of dibutyryl adenosine 3':5' monophosphate (Bu2cAMP, 5 X 1 0 -4 m) and theophylline (5 X 1 0 ~ 4 m) to serum-free cultures caused a further striking increase of tyrosinase activity and melanin formation, while treatment of serum containing cultures with Bu2eAMP and theophylline showed only a slight rise in melanogenesis. It is sug­ gested that these stimulatory effects are mediated by an increased intracellular cAMP level, since a correlation between the degree of melanogenesis and cellular cAMP content was indicated. Treat­ ment of serum-free or serum-containing cultures with the phosphodiesterase inhibitor theophylline (5 X 1 0 -4 — 1 X 1 0 -3 m) alone revealed only a slight enhancement (about 20%) of melanogenesis. Because augmentation of melanogenesis by serum-free medium alone or together with Bu,cAMP and theophylline was prevented by cycloheximide (or actinomycin D), de novo protein synthesis seems to be required for these stimulatory effects. 
  Reference    (Z. Naturforsch. 32c, 567 [1977]; received February 24 1977) 
  Published    1977 
  Keywords    Melanoma, Cell Culture, Serum Removal, Tyrosinase, Melanin 
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 TEI-XML for    default:Reihe_C/32/ZNC-1977-32c-0567.pdf 
 Identifier    ZNC-1977-32c-0567 
 Volume    32 
2Author    L. Britsch, W. Heller, H. GrisebachRequires cookie*
 Title    Conversion of Flavanone to Flavone, Dihydroflavonol and Flavonol with an Enzyme System from Cell Cultures of Parsley  
 Abstract    Soluble enzyme preparations from irradiated cell suspension cultures of parsley (Petroselinum hortense Hoffm.) catalyse the conversion o f flavanone to flavone, dihydroflavonol and flavonol. These reactions require 2-oxoglutarate, Fe2+ and ascorbate as cofactors. In the presence o f these cofactors conversion of dihydroflavonol to flavonol was also observed. With this system in vitro biosynthesis of radioactive flavone, dihydroflavonol and flavonol from [2-14C]malonyl-CoA and 4-coumaroyl-CoA in good yield and with high specific activity is possible. We postulate that synthesis of flavone and flavonol from flavanone proceeds via 2-hydroxy-and 2,3-dihydroxyflavanone, respectively, with subsequent dehydration. The microsomal fraction of the parsley cells contains an NADPH-dependent flavanone 3'-hydroxylase. 
  Reference    Z. Naturforsch. 36c, 742—750 (1981); received June 3 1981 
  Published    1981 
  Keywords    Flavonoids, Biosynthesis, Dioxygenases, Petroselinum hortense, Cell Cultures 
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 TEI-XML for    default:Reihe_C/36/ZNC-1981-36c-0742.pdf 
 Identifier    ZNC-1981-36c-0742 
 Volume    36 
3Author    HildegardM. Aria, W. Arneck, H. Anns, Ulrich SeitzRequires cookie*
 Title    3 ß-Hydroxysteroid Oxidoreductase in Suspension Cultures of Digitalis lanata EH RH  
 Abstract    A 3 ß-hydroxysteroid oxidoreductase was isolated and characterized in the m icrosomes o f Digitalis lanata cell cultures. The enzyme catalyzes the conversion o f 5a-pregnane-3,20-dione to 5a-pregnan-3 ß-ol-20-one and requires N A D (P)H 2. The enzyme was found to have a pH optimum o f 8.0. The reaction had an optimum incubation temperature o f 25 °C with linear reduction for the first 4 h, reaching maximum enzyme activity after 7 h. Substrate kinetics for 5a-pregnane-3,20-dione and N A D P H 2 resulted in apparent A^-values o f 1 8 .5 -2 0 (iM for 5a-pregnane-3,20-dione and 5 0 -1 2 0 |iM for the co-substrate N A D P H ,. In order to localize 3 ß-hydroxysteroid oxidoreductase differential centrifugation as well as linear sucrose density gradient centrifugation were performed. The results obtained lead to the conclusion that 3 ß-hydroxysteroid oxidoreductase is not associated with a single cell compartment, but con­ sists o f a major soluble part and a markedly smaller part o f endoplasmic reticulum-associated activity. 
  Reference    Z. Naturforsch. 45c, 963 (1990); received July 16. 1990 
  Published    1990 
  Keywords    Cell Cultures, Digitalis lanata, 3 ß-Hydroxysteroid Oxidoreductase, Steroids 
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 TEI-XML for    default:Reihe_C/45/ZNC-1990-45c-0963.pdf 
 Identifier    ZNC-1990-45c-0963 
 Volume    45 
4Author    Didier Hallard, Ernst Bleichert, HubertG. Agnon, Satoshi Tahara, Ragai IbrahimRequires cookie*
 Title    Production and Release of Isoflavonoids by Lupin Cell Cultures  
 Abstract    Cell cultures derived from white lupin (Lupinus albus) radicles consist o f a mixture o f friable cell aggregates and finely divided cells. Both types o f tissue accumulate two isoflavonoid aglu-cones, genistein and 2'-hydroxygenistein, their 7-O-glucosides, and their respective 6-, 8-, and 3'-monoprenyl-, as well as the 6,3'-diprenyl derivatives. M ost o f these metabolites are differen­ tially released in the culture medium. The relative am ounts o f aglucones, glucosides and preny-lated derivatives that are produced by the aggregates and cells, as well as those excreted into the medium, are discussed in relation to culture growth. 
  Reference    Z. Naturforsch. 47c, 346 (1992); received December 23 1991 
  Published    1992 
  Keywords    Lupinus albus, Fabaceae, Cell Culture, Isoflavonoid Production, Genistein 
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 TEI-XML for    default:Reihe_C/47/ZNC-1992-47c-0346.pdf 
 Identifier    ZNC-1992-47c-0346 
 Volume    47 
5Author    Christine Gareis, Christiane Rivero, Ingolf Schuphan, Burkhard SchmidtRequires cookie*
 Title    Plant Metabolism of Xenobiotics. Comparison of the Metabolism of 3.4-Dichloroaniline in Soybean Excised Leaves and Soybean Cell Suspension Cultures  
 Abstract    Excised leaves and cell suspension cultures of soybean (Glycine m ax L.) were incubated with [UL-14C]-3,4-dichloroaniline. The compound was almost completely metabolized after 48 h in both systems; it was apparent that the major detoxification pathways present in the excised leaves were also present in the cultured cells. Besides considerable amounts of insoluble resi­ dues, the N-glucosyl and the N-malonyl conjugates of 3,4-dichloroaniline, and a yet unknown metabolite was formed in the excised leaves; tentatively the latter was identified with the 6'-0-malonylester of N-glucosyl-3,4-dichloroaniline. The cell suspension cultures produced predominantly the N-malonyl conjugate, besides negligible amounts of the N-glucosyl conju­ gate, and insoluble residues; the majority of the N-malonyl compound was excreted into the medium. It was shown, that the metabolism of 3,4-dichloroaniline in excised leaves and cell suspension cultures of soybean was directed towards different end products: the excised leaves were able to make extensive use of cell wall structures as a deposit for xenobiotic bound resi­ dues, resembling plants in this respect; lack of these structures in the cultured soybean cells resulted in a soluble end product, namely the N-malonyl conjugate. 
  Reference    Z. Naturforsch. 47c, 823—829 (1992); received August 5 1992 3. 
  Published    1992 
  Keywords    4-Dichloroaniline, Metabolism, Soybean, Cell Culture, Excised Leaves 
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 TEI-XML for    default:Reihe_C/47/ZNC-1992-47c-0823.pdf 
 Identifier    ZNC-1992-47c-0823 
 Volume    47 
6Author    Gerold Reila, RalfG. Ünter BergerhRequires cookie*
 Title    Accumulation of Chlorophyll and Essential Oils in Photomixotrophic Cell Cultures of Citrus sp  
 Abstract    Heterotrophically or photomixotrophically initiated callus cultures o f Citrus paradisi, C. limon and C.aurantifolia were grown on different nutrient media and under different light regimes. Calli of C.paradisi that contained > 1 4 0 mg chlorophyll per kg wet weight accumu­ lated about 40 volatile mono-and sesquiterpene hydrocarbons, oxigenated terpenes and ali­ phatic aldehydes. Upon five subcultivations the best yielding callus contained about 5% (186 mg x k g 1 wet wt) of the volatiles found in peel tissue (exo/m esocarp section), and about the twentyfold amount of that found in the fleshy endocarp. The com position of the essential oils from most of the cell cultures equalled grapefruit peel oil, but was shifted to a more fruit flesh-like composition, after the concentration of gellan gum in the medium was increased from 3 to 9 g per L. C. limon produced 11 m onoterpenes and n-nonanal (40 mg x kg"1 wet wt max.), and C.aurantifolia yielded limonene only (4.4 mg x kg'1 wet wt max.). For all of the indicated species chlorophyll content and accumulation of volatiles were positively corre­ lated. Addition of exogenous valencene to suspended cells of C.paradisi led to a stable con­ centration of the conversion product nootkatone. This stably maintained level suggested that a decreased catabolism of available carbon sources might have accounted for the significant accumulation of essential oil constituents. 
  Reference    Z. Naturforsch. 51c, 657—6 (1996); received March 12/June 18 1996 
  Published    1996 
  Keywords    Citrus, Cell Culture, Photomixotrophy, Oligoprenoids, Limonene 
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 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0657.pdf 
 Identifier    ZNC-1996-51c-0657 
 Volume    51 
7Author    D. Ieter, Strack An, M. Aria Bokern, Jochen Berlin An D, Sabine SiegRequires cookie*
 Title    Metabolie Activity of Hydroxycinnamic Acid Glucose Esters in Cell Suspension Cultures of Chenopodium rubrum  
 Abstract    Cell suspension cultures o f Chenopodium rubrum accumulate high amounts of metabolically active glucose esters of ^?-coumaric and ferulic acid. Pulse-labelling experiments using [14C]phe-nylalanine and application o f the phenylalanine ammonia-lyase (PAL) inhibitor L-a-aminooxy-/3-pnenylpropionic acid (AOPP) revealed that the glucose esters are subject to high turnover. A considerable portion o f the ferulic acid was found as an insoluble component, probably bound to cell wall material. Application of m-fluoro-DL-tyrosine (MFT), an effective inhibitor o f tyrosine biosynthesis via L-arogenate, markedly increased the amount of 1-p-coumaroyl-and 1-feruloyl-glucose accumulated. 
  Reference    Z. Naturforsch. 39c, 902—907 (1984); received May 16 1984 
  Published    1984 
  Keywords    Chenopodium rubrum, Cell Culture, Hydroxycinnamic Acid, Glucose Ester, Betalain 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-0902.pdf 
 Identifier    ZNC-1984-39c-0902 
 Volume    39 
8Author    KlausP B Ad Er, Judith SchülerRequires cookie*
 Title    Inhibition of the Photosynthetic Electron Transport by Pyrethroid Insecticides in Cell Cultures and Thylakoid Suspensions from Higher Plants  
 Abstract    Synthetic pyrethroid insecticides with different molecular structures have been investigated with respect to their effect on photosynthetic electron transport reactions in chloroplast sus­ pensions and cell cultures from higher plants. The fluorescence induction curves of tobacco (Nicotiana tabacum) leaves and tomato cells were substantially affected by permethrin and cypermethrin resulting in a strong increase of the maximum fluorescence. Application of different concentrations (0.3-1.2 m M) of the respective chemical abolishes virtually any ki­ netics of the normal Kautsky effect. Oxygen evolution from cell cultures from tomato (Ly-copersicon peruvianum) was completely inhibited by cypermethrin. Analysis of partial reac­ tions of the photosynthetic electron transport showed that both a methylviologen-mediated Mehler reaction and a ferricyanide-driven Hill reaction were quantitatively inhibited by e.g. fenvalerate. On the other hand, neither a silicomolybdate-driven Hill reaction nor a methylvi-ologen-driven Mehler reaction using dichlorophenol indophenol/ascorbate as electron donors could be inhibited by the pyrethroid. The analyses suggest that pyrethroid insecticides in­ terfere with the photosynthetic electron transport at the same site as urea-type herbicides do. Depending on the molecular structure and on the halogen compound in the molecule, however, different pyrethroids are more or less phytotoxic to the investigated photosynthetic membranes -cypermethrin with two Cl-substituents requires much higher concentrations to be applied for significant inhibition of the electron transport reactions than the Br-derivative deltamethrin does. Moreover, qualitative differences have to be taken into account. In the case of fenvalerate the effect seems to exist in a type of all-or-nothing reaction when the reaction centres are inhibited by the pyrethroid. None of the S-states nor the transition probabilities are specifically influenced by increasing concentrations of fenvalerate. In the case of deltamethrin, however, it was found that the overreduced state S_i is significantly increased at the expense of both Si and S(). Moreover, the miss parameter a is increased in the case of deltamethrin addition. The results and the significance of different substituents for the investigated pyrethroids are discussed. 
  Reference    Z. Naturforsch. 51c, 721—728 (1996); received April 25/June 20 1996 
  Published    1996 
  Keywords    Photosynthesis, Electron Transport, Oxygen Evolution, Pyrethroid Insecticide, Cell Culture 
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 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0721.pdf 
 Identifier    ZNC-1996-51c-0721 
 Volume    51 
9Author    Bruno Wolters, U. Do EilertRequires cookie*
 Title    Acridonepoxidgehalte in Kalluskulturen von Ruta graveolens und ihre Steigerung durch Mischkultur mit Pilzen.* Accumulation of Acridone-Epoxides in Callus C ultures o f Ruta graveolens Increased by Coculture with Not Host-Specific Fungi  
 Abstract    The classic attempt to find optimum culture conditions lead to hormonautotrophic cultures and to dark grown cultures. We made the new attempt to rise the yield o f rutacridone-epoxides by co­ culture with not hostspecific fungi. Conditions were chosen that only diffusible elicitors could in­ fluence callus tissue. 14 days of coculture mostly caused reduced acridone-epoxide content, growthrate and up to total disappearance of chlorophyll. Within 3 — 7 days o f coculture some fun­ gi induced a significant rise of acridone-epoxide content (up to 50-fold). Culture filtrates o f these fungi showed comparable effects. Our results proved the acridone-epoxides to be phytoalexins. The use o f fungal elicitors could be a new method to increase secondary product accumulation in tissue culture. 
  Reference    Z. Naturforsch. 37c, 575 (1982); received March 22 1982 
  Published    1982 
  Keywords    Acridone-Epoxide, Cell Culture, Coculture with Fungi, Phytoalexin, Ruta graveolens 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0575.pdf 
 Identifier    ZNC-1982-37c-0575 
 Volume    37 
10Author    Helmut Heinle, Gerhard Sigg, Amo Reich, Klaus-Ulrich ThiedemannRequires cookie*
 Title    Metabolie Effects of Direct Current Stimulation on Cultured Vascular Smooth Muscle Cells  
 Abstract    Vascular smooth muscle cells from rabbit arteries were grown in tissue culture and stimulated by DC impulses (1 mA, 1 V, 10 Hz, 1 ms/imp). Scanning microscopic examination disclosed that in stimulated cultures the cell surface was enlarged by numerous microvilli. This was interpreted as being indicative of an increase in cell activity. Cellular metabolism was character­ ized by analyzing the incubation medium for glucose, glutamate/glutamine, and lactate. When compared to unstimulated controls, stimulation caused an increase in the uptake of glucose and glutamine as well as an increased lactate production. The enhancing effect on metabolism was prevented when the "calcium antagonist" verapamil was present (5 x 10-6 m). Although the exact mechanism by which D C stimulation influences the cells remains obscure, this finding indicates an important mediating role of Ca2+ ions. 
  Reference    Z. Naturforsch. 39c, 1141—1144 (1984); received August 8 1984 
  Published    1984 
  Keywords    Cell Culture, Direct Electric Stimulation, Metabolie Effects, Calcium Antagonist, Vascular Smooth Muscle 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-1141.pdf 
 Identifier    ZNC-1984-39c-1141 
 Volume    39 
11Author    Joachim Bollmann, Klaus HahlbrockRequires cookie*
 Title    Timing of Changes in Protein Synthesis Pattern in Elicitor-Treated Cell Suspension Cultures of Parsley ( Petroselinum crispum)  
 Abstract    The timing o f changes in the protein synthesis pattern o f elicitor-treated, [35S]methionine-labelled parsley cells (Petroselinum crispum) was analyzed by two-dimensional gel electropho­ resis. Five groups were distinguished from a large number o f elicitor-responsive as well as un­ responsive proteins. Two groups were synthesized de novo either early or late after elicitor ap­ plication; two other groups were strongly reduced in their rates o f synthesis either early or late after elicitor application; and one group was not appreciably affected at all. The elicitor-in-duced changes altered the total protein com position considerably. A few selected, induced pro­ teins were functionally identified. These included two early induced enzymes, phenylalanine amm onia-lyase (PAL) and 4-coum arate:C oA ligase (4C L), and a late induced enzyme, a ber-gaptol O-methyltransferase (BM T) which is specifically involved in the biosynthesis o f furano-coumarin phytoalexins. The biological significance o f the observed differential timing o f changes in protein synthesis rates is discussed. 
  Reference    Z. Naturforsch. 45c, 1011 (1990); received May 30 1990 
  Published    1990 
  Keywords    Cell Culture, Elicitor, Petroselinum crispum, Protein Synthesis, Two-Dim ensional Gel Electrophoresis 
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 TEI-XML for    default:Reihe_C/45/ZNC-1990-45c-1011.pdf 
 Identifier    ZNC-1990-45c-1011 
 Volume    45 
12Author    Abteilung Zellchemie, G.S FRequires cookie*
 Title    Activities and Regulation of Enzymes of Carbohydrate Metabolism in Spruce ( Picea abies) M einrad Boll  
 Abstract    Activities o f the glycolytic enzymes were determined in seedlings, callus cultures and cell sus­ pension cultures o f spruce (Picea abies) (L.) (Karst). The rate-limiting enzymes o f the pathway were the hexokinases, ATP: phosphofructo-kinase, fructose-1,6-bisphosphatase and pyruvate kinase. Two phosphofructokinases were found: A T P : fructose-6-phosphate 1-phosphotransferase (PFK) and pyrophosphate :fructose-6-phosphate 1-phosphotransferase (PFP). In the presence o f its activator fructose-2,6-bisphos-phate, PFP had a 4 -5-fold higher specific activity than PFK. PFP could be activated about 20-fold by fructose-2,6-bisphosphate at saturating concentrations o f the substrates (fructose-6-phosphate and pyrophosphate). The increase o f Fmax was accompanied by a strong increase in the apparent affinity o f the enzyme for the substrates. Km for fructose-6-phosphate and pyrophosphate was 0.44 mM and 24 fiM, respectively. Ka for fructose-2,6-bisphosphate was 24 nM. In seedlings, specific activity o f the glycolytic enzymes was 3 0 -3 0 0 percent higher in the hypocotyls, except for fructose-1,6-bisphosphate aldolase, glyceraldehyde-3-phosphate de­ hydrogenase and phosphoglycerate kinase, their activity being 1 0 0 -150 percent higher in the cotyledons, This distribution remained unchanged during periods o f 2 -16 weeks o f cultiva­ tion o f the seedlings. In callus cultures and in cell suspension cultures, grown mixotrophically with different car­ bohydrates, all enzymes were between 1-and 7-fold higher than in autotrophically grown seed­ lings. Incubation o f seedlings in mineral salt mixture containing a carbohydrate resulted in a rapid coordinate increase o f the activities to the levels o f callus-or cell suspension cultures. This induction required a carbohydrate and oxygen. During prolonged cultivation o f cell sus­ pension cultures, when carbohydrate became limiting, activity o f the enzymes slowly declined. 
  Reference    Z. Naturforsch. 46c, 597 (1991); received Dezember 7 1990/April 4 1991 
  Published    1991 
  Keywords    Picea abies, Cell Culture, Carbohydrate M etabolism, PP, -phosphofructokinase, Enzyme Regulation 
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 TEI-XML for    default:Reihe_C/46/ZNC-1991-46c-0597.pdf 
 Identifier    ZNC-1991-46c-0597 
 Volume    46 
13Author    J. Berlinab, L. Fecker, C. R. Ügenhagenab, C. S. Atorc, D. S. Trackd, L. W. Itted, V. W. RaybRequires cookie*
 Title    Isoflavone Glycoside Formation in Transformed and Non-Transformed Suspension and Hairy Root Cultures of Lupinus polyphyllus and Lupinus hartwegii  
 Abstract    sides Transformed cell suspension and hairy root cultures were established by infecting seedlings o f Lupinus polyphyllus and L. hartwegii with various wild type strains o f Agrobacterium tume-faciens and A. rhizogenes. Transformation o f the cultures was confirmed either by their phyto­ hormone autotrophy, detection o f opines or southern analysis. Glueosides o f genistein and 2'-hydroxygenistein, were found to be the main secondary metabolites in normal and trans­ formed suspension cultures as well as in hairy root cultures. Although some o f the isoflavone glycosides o f the cultures were apparently new constituents o f Lupinus, they were afterwards also found in young seedlings. 
  Reference    Z. Naturforsch. 46c, 725 (1991); received April 23 1991 
  Published    1991 
  Keywords    Lupinus polyphyllus, Lupinus hartwegii, Cell Cultures, Hairy R oot Cultures, Isoflavone Gluco- 
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 TEI-XML for    default:Reihe_C/46/ZNC-1991-46c-0725.pdf 
 Identifier    ZNC-1991-46c-0725 
 Volume    46