Isolation and characterization of an UDPG-dependent glucosyltransferase activity from Rauwolfia serpentina Benth. cell suspension cultures

1994 ◽  
Vol 72 (1) ◽  
pp. 51-55 ◽  
Author(s):  
Ralf Lutterbach ◽  
Carl Michael Ruyter ◽  
Joachim Stöckigt
Keyword(s):  
Enzyme Activity ◽  
Cell Suspension ◽  
Cell Suspension Cultures ◽  
Callus Cultures ◽  
Suspension Cultures ◽  
Rauwolfia Serpentina ◽  
Isolation And Characterization ◽  
Membrane Bound ◽  
Plant Families

From cell suspension cultures of Rauwolfia serpentina Benth. a new enzyme activity was isolated and its properties determined. The enzyme is a soluble protein and catalyzes the transfer of a glucose moiety from UDPG to a wide variety of phenolic compounds with p-nitrophenol as one of the best substrates (Km = 1.21 mM, UDPG = 0.54 mM). In contrast to the membrane-bound UDPG: vomilenine-21-OH-β-D-glucosyltransferase from Rauwolfia serpentina cells, this enzyme is not able to glucosylate indole alkaloids. The enzyme activity has been detected in 14 callus cultures belonging to 10 different plant families.

Characterization of Volatile Constituents from Photomixotrophic Cell Suspension Cultures of Ruta graveolens

1984 ◽  
Vol 39 (6) ◽  
pp. 525-530 ◽  
Author(s):  
Friednch Drawert ◽  
Ralf G. Berger ◽  
Rolf Godelmann ◽  
Susanne Collin ◽  
Wolfgang Barz
Keyword(s):  
Acetic Acid ◽  
Cell Suspension ◽  
Cell Suspension Cultures ◽  
Callus Cultures ◽  
Suspension Cultures ◽  
Ruta Graveolens ◽  
Straight Chain ◽  
Methylbutyric Acid ◽  
Aliphatic Esters

Photomixotrophic cell suspension cultures of Ruta graveolens were qualitatively and quantita­tively analyzed by gaschromatography and mass spectroscopy for volatile compounds. The terpenoid hydrocarbons geijerene and pregeijerene, the C9-C13 methylketones and a series of aliphatic esters, respectively, were found as main constituents. The esters consisted of acetic acid, 2-methylbutyric acid and 3-methylbutyric acid which were esterified with straight chain or branched C8-C11 alcohols. The data are discussed in comparison to previous studies on callus cultures.

3-Hydroxy-3-methylglutaryl Coenzyme A Reductase from Spruce ( Picea abies). Properties and Regulation

1990 ◽  
Vol 45 (9-10) ◽  
pp. 973-979 ◽  
Author(s):  
Meinrad Boll ◽  
Angelika Kardinal
Keyword(s):  
Enzyme Activity ◽  
Picea Abies ◽  
Cell Suspension ◽  
Specific Activity ◽  
Reductase Activity ◽  
Cell Suspension Cultures ◽  
Callus Cultures ◽  
Suspension Cultures ◽  
Phase Cell ◽  
Ph Optimum

Abstract HM GCoA reductase was identified in seedlings, callus cultures, cell suspension cultures and in needles of spruce ( Picea abies) (L.) (Karst). Activity was found in both the 18 K pellet and in the 105 K pellet with different ratios between the two fractions from the various sources. The enzyme has a pH-optimum of 7.9 and an absolute requirement for NADPH . The presence of a thiol reagent such as dithiothreitol is required for activity. Km for HM G CoA is 20 -25 μM. Detergents have differential effects on the activity. In seedlings, enzyme activity was considerably higher in the hypocotyls than in the cotyledons. Enzyme activity was high in dark-grown and low in light-grown seedlings. When the light conditions were reversed, levels of activity adapted to the respective new conditions (increase or decline of specific activity). Aerobic incubations of seedlings, callus cultures or needles in medium containing a carbon source, resulted in a large (up to 20-fold) transient increase of HMGCoA reductase activity. Transfer of stationary phase cell suspension cultures into new medium caused a similarly large increase of activity. A number of carbohydrates induced the enzyme, glucose, fructose and sucrose being most effective. The increase of activity was prevented by cycloheximide. All changes of activity were much more pronounced in the 18 K pellet HMG CoA reductase

Isolation and Characterization of Flavonol Converting Enzymes from Mentha piperita Plants and from Mentha arvensis Cell Suspension Cultures

1979 ◽  
Vol 34 (3-4) ◽  
pp. 200-209 ◽  
Author(s):  
Gudrun Frey-Schröder ◽  
Wolfgang Barz
Keyword(s):  
Cell Suspension ◽  
Oxidase Activity ◽  
Enzyme Reaction ◽  
Cell Suspension Cultures ◽  
Suspension Cultures ◽  
Mentha Piperita ◽  
Mentha Arvensis ◽  
Iaa Oxidase ◽  
Isolation And Characterization ◽  
Group I

Abstract Peroxidases from several plants, including horseradish peroxidase, were capable of converting flavonols to the corresponding 2,3-dihydroxyflavanones in presence of H2O2 . Contrastingly, protein extracts from Mentha piperita plants and Mentha arvensis cell suspension cultures perform ed the same enzymatic step in absence of H2O2 , but only with quercetin, not with kaempferol. H2O2-independent, quercetin converting enzymes were isolated and purified from these extracts, and they could be classified in two groups according to the extent of stimulation of the enzyme reaction by H2O2 . Enzymes from group I were stimulated by exogenous H2O2 , and they resembled horse­ radish peroxidase in several aspects. They possessed IAA oxidase activity, but quercetin was the preferred substrate. Enzymes from group II from the plants appeared to be a distinctly different set of enzymes. They were not stimulated by H2O2 , but required molecular oxygen and converted only 3,3′,4′-trihydroxyflavones under aerobic conditions. Also, they showed no Soret-bands and possessed no IAA oxidase activity. These proteins appear to be a new class of enzymes participating in the first step of flavonol degradation in plants.

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