2,4-d and alkaloid accumulation in periwinkle cell suspensions.omission of 2,4-d from culture medium during one subculture of catharanthus roseus cells, strain c20, resulted in an increased alkaloid accumulation, without effect on growth. alkaloid accumulation, rather than growth, seemed to be more sensitive to 2,4-d. 2,4-d inhibited alkaloid accumulation essentially during growth phase, but its inhibitory effect during this period was partially reversible. as this reversibility was underlined only during the stationary phase, this suggested that this actio ...19947849107
purification and partial characterization of microsomal nadh-cytochrome b5 reductase from higher plant catharanthus roseus.a simple three step procedure was used to purify microsomal nadh-cytochrome b5 (ferricyanide) reductase to homogeneity from the higher plant c. roseus. the microsomal bound reductase was solubilized using zwitterionic detergent-chaps. the solubilized reductase was subjected to affinity chromatography on octylamino sepharose 4b, blue 2-sepharose cl-6b and nad(+)-agarose. the homogeneous enzyme has an apparent molecular weight of 33,000 as estimated by sds-page. the purified enzyme catalyzes the r ...19938267585
putative sites of cytokinin action during their enhancing effect on indole alkaloid accumulation in periwinkle cell suspensions.the effects of cytokinins on the different branches of the indole alkaloid pathway were investigated in catharanthus roseus cell cultures. addition of zeatin to a 2,4-dichlorophenoxyacetic acid-containing medium decreased tryptamine levels and increased the bioconversion of secologanin to ajmalicine. zeatin also enhanced the geraniol-10 hydroxylase activities and modified the indole alkaloid pattern. the results are discussed in the light of previous works showing that cytokinins have a positive ...199324201970
effect of terpenoid precursor feeding and elicitation on formation of indole alkaloids in cell suspension cultures of catharanthus roseus.the effects of terpenoid precursor feeding and elicitation by a biotic elicitor on alkaloid production of catharanthus roseus suspension cultures were studied. after addition of secologanin, loganin or loganic acid an increase in the accumulation of ajmalicine and strictosidine and a decrease of tryptamine level was observed in non-elicited cells. elicitation increased tryptamine accumulation in non-fed cells but it did not further increase alkaloid accumulation in precursor-fed cells. a decreas ...199324201968
induced responses in three alkaloid-containing plant this paper we test three plant species for the inducibility of their alkaloid production. the plants were heavily damaged by cutting off 50% of their leaf surface using a pair of scissors. the cut-off leaf tips were used as controls for possible diurnal fluctuations. after 3, 6, 12, 24 and 48 h, respectively, the leaf bases of the damaged plants were harvested and the alkaloid concentration was measured. in senecio jacobaea the pyrrolizidine alkaloid (pa) concentration in damaged plants decre ...199328314020
subcellular localization of tryptophan decarboxylase, strictosidine synthase and strictosidine glucosidase in suspension cultured cells of catharanthus roseus and tabernaemontana divaricata.the subcellular localization of tryptophan decarboxylase, strictosidine synthase and strictosidine glucosidase in suspension cultured cells of catharanthus roseus (l.) g. don and tabernaemontana divaricata (l.) r. br. ex roem. et schult, was investigated. it was found that tryptophan decarboxylase is an extra-vacuolar enzyme, whereas strictosidine synthase is active inside the vacuole. strong indications were obtained for the localization of strictosidine glucosidase on the outside of the tonopl ...199324201788
phosphatidate kinase, a novel enzyme in phospholipid metabolism (purification, subcellular localization, and occurrence in the plant kingdom).microsomal membranes from suspension-cultured catharanthus roseus cells possess an enzymic activity that catalyzes the atp-dependent phosphorylation of phosphatidic acid (pa) to form diacylglycerol pyrophosphate (h. behrbohm, j.b. wissing [1993] febs lett 315: 95-99). this enzyme activity, pa kinase, was purified and characterized. plasma membranes, obtained from c. roseus microsomes by aqueous two-phase partitioning, were extracted, and pa kinase was purified 3200-fold by applying different chr ...199312231900
isolation of cytochrome p-450 cdna clones from the higher plant catharanthus roseus by a pcr strategy.cytochrome p-450 monooxygenases are membrane-bound enzymes involved in a wide range of biosynthetic pathways in plants. an efficient pcr strategy for isolating cytochrome p-450 cdna clones from plant cdna libraries is described. a set of degenerate primers for pcr amplification was designed to recognize nucleotide sequences specifying the highly conserved haembinding region of cytochrome p-450 proteins. using this primer set and a non-specific primer, complementary to either the poly(a) tail of ...19938507838
a structured model describing carbon and phosphate limited growth of catharanthus roseus plant cell suspensions in batch and chemostat culture.the growth of plant cell suspension cultures of catharanthus roseus in batch fermentors was studied at different initial phosphate levels of the medium. on the basis of the observations and existing knowledge with respect to phosphate metabolism in cultured c. roseus cells, a structured mathematical model was developed for the description of the kinetics of growth and intracellular accumulation of glucose and phosphate, as a function of glucose and phosphate supply. it was shown that the model o ...199318609621
induction of ajmalicine formation and related enzyme activities in catharanthus roseus cells: effect of inoculum catharanthus roseus cell cultures the time courses of four enzyme activities, tryptophan decarboxylase (tdc), strictosidine synthase (sss), geraniol-10-hydroxylase (g10h) and anthranilate synthase (as), and alkaloid accumulation were compared under two different culture conditions (low-inoculum density and high-inoculum density on induction medium) and a control on growth medium. in growth medium a transient increase in tdc activity was first observed after which g10h reached its maximum acti ...19937763550
purification, characterization, and kinetic analysis of a 2-oxoglutarate-dependent dioxygenase involved in vindoline biosynthesis from catharanthus roseus.a 2-oxoglutarate-dependent dioxygenase (ec which catalyzes the hydroxylation at position 4 of the indole alkaloid, desacetoxyvindoline has been purified to near homogeneity from catharanthus roseus. the purification procedure combined conventional chromatographic methods and cosubstrate affinity chromatography on alpha-ketoglutarate-sepharose. the specific activity of the 4-hydroxylase was enriched over 2000-fold compared to the crude homogenate with a recovery of 1.6%. the molecular ...19938449913
effects of near-ultraviolet light on alkaloid production in catharanthus roseus plants.artificial near-ultraviolet light with a peak at 370 nm and the light of natural radiation with wavelengths between 290 and 380 nm stimulated the synthesis of dimeric indole alkaloids in intact plants of catharanthus roseus. the artificial light also specifically stimulated an in vitro fmn-mediated, non-enzymatic coupling of vindoline and catharanthine to synthesize an iminium intermediate, the in vivo precursor of dimeric alkaloid synthesis. these results suggest that near-ultraviolet light is ...199317230336
scaleup of ajmalicine production by plant cell cultures of catharanthus roseus.the effect of scaleup on he production of ajmalicine by a catharanthus roseus cell suspension culture in a selected induction medium were studied. in preliminary experiments it was observed that the culture turned brown and the production was inhibited upon transfer from a shake flask to a stirred bioreactor with forced aeration. two factors were recognized as the potential origin of the differences between shake flask and bioreactor cultures: gas composition and mechanical shear forces. these f ...199318609545
nucleotide sequence of a cdna encoding 3-hydroxy-3-methylglutaryl coenzyme a reductase from catharanthus roseus. 199216653173
isolation of vindoline from catharanthus roseus by supercritical fluid extraction.vindoline was extracted from the leaves of catharanthus roseus over the ranges of 35-70 degrees c and 100-300 bar using supercritical carbon dioxide with and without the addition of 3 wt % ethanol as a cosolvent. the vindoline contents in the extracts were determined by hplc and identified by lc/ms. the remarkable highest vindoline concentration, 58 wt %, was obtained at the lowest temperature, 35 degrees c, and the highest pressure, 300 bar, of this study. the use of a cosolvent only slightly i ...20151369042
phytochrome is involved in the light-regulation of vindoline biosynthesis in catharanthus.the enzyme acetylcoenzyme a:deacetylvindoline 4-o-acetyl-transferase (dat) catalyzes the final step in the biosynthesis of the monoterpenoid indole alkaloid, vindoline. previous studies have shown that the appearance of dat activity in etiolated seedlings of catharanthus roseus is induced by exposure of seedlings to light and that enzyme activity is restricted principally to the cotyledons. evidence is now presented that phytochrome is involved in the light-mediated induction of dat activity in ...199216653011
auxins induce tryptophan decarboxylase activity in radicles of catharanthus seedlings.germinating seedlings of catharanthus roseus produce monoterpenoid indole alkaloids as a result of a transient increase of tryptophan decarboxylase (tdc) activity. the influence of auxins on this transient rise of tdc activity was studied. external application of indolebutyric acid or 2,4-dichlorophenoxyacetic acid at a concentration of 20 to 40 mum enhanced and prolonged the rise in tdc activity in developing seedlings. auxin treatment also influenced the morphology of the seedlings; it induced ...199216653009
biotransformation of tabersonine in cell suspension cultures of catharanthus investigate the reactions involved in the biosynthesis of vindoline from tabersonine, the bioconversion products formed when the latter compound was fed to cell suspension cultures of catharanthus roseus were isolated and characterized. two biotransformation products of tabersonine were isolated and shown to be lochnericine, which is formed by epoxidation of tabersonine at positions 14, 15, and lochnerinine, the 11-methoxylation product of lochnericine. the bioconversion ratio of the main bio ...19921368411
identification of an essential histidine residue at the active site of the tonoplast malate carrier in catharanthus roseus cells.the involvement of a histidyl residue in the binding or translocation step was investigated in the malate carrier at the tonoplast of catharanthus roseus cells. the transport rate was strongly stimulated when the ph of the incubation medium was decreased from ph 7.0 to 5.0. the histidine-specific reagent diethylpyrocarbonate (depc) efficiently inhibited the activity of the malate carrier. inhibition developed rapidly and was completed after 5 min at a concentration of 2 mm depc. the original sub ...19921433274
cytokinin-enhanced accumulation of indole alkaloids in catharanthus roseus cell cultures - the factors affecting the cytokinin response.cytokinins were found to stimulate the alkaloid synthesis induced by removing auxin from the medium of a cell line of catharanthus roseus. diluting the mineral salts of the culture medium decreased the alkaloid production but increased the "sensitivity" of the cells. addition of high levels of ca(2+), mg(2+) or sr(2+) to b5 media in which the mineral salts were diluted to 5-40%, increased the alkaloid production. the latter effect is related only partially to enhanced osmotic potential.199224201541
the effect of temperature on hairy root cultures of catharanthus roseus: growth, indole alkaloid accumulation and membrane lipid composition.cultivation of catharanthus roseus hairy root cultures at different temperatures was found to have an effect on growth rate and indole alkaloid content as well as lipid composition. when lowering the temperature, the roots responded by increasing the degree of unsaturation of cellular lipids, which was mainly due to an increased proportion of linolenic acid in the main lipid classes. the modifications in lipid composition were obviously necessary for the roots to retain the proper cell membrane ...199224201540
the effect of temperature on growth, indole alkaloid accumulation and lipid composition of catharanthus roseus cell suspension cultures.cell suspension cultures of catharanthus roseus were used to study the effect of temperature on plant cell lipids and indole alkaloid accumulation. lowering the cultivation temperature increased the total fatty acid content per cell dry weight relative to that at higher temperatures, mainly because of increased accumulation of unsaturated c18 acids. in addition, an increase in the relative proportion of phosphatidylcholine and phosphatidylethanolamine was observed. within individual lipids, the ...199224201539
cytoplasmic acidification induced by inorganic phosphate uptake in suspension cultured catharanthus roseus cells: measurement with fluorescent ph indicator and p-nuclear magnetic resonance.cytoplasmic acidification during inorganic phosphate (pi) absorption by catharanthus roseus cells were studied by means of a fluorescent ph indicator, 2',7'-bis-(2-carboxyethyl)-5 carboxyfluorescein (acetomethylester) (bcecf), and (31)p-nuclear magnetic resonance spectroscopy. cytoplasmic acidification measured by decrease in the fluorescence intensity started immediately after pi application. within a minute or so, a stable state was attained and no further acidification occurred, whereas pi ab ...199216668939
development of a helical-ribbon impeller bioreactor for high-density plant cell suspension culture.a double helical-ribbon impeller (hri) bioreactor with a 11-l working volume was developed to grow high-density catharanthus roseus cell suspensions. the rheological behavior of this suspension was found to be shear-thinning for concentrations higher than 12 to 15 g dw . l(-1). a granulated agar suspension of similar rheological properties was used as a model fluid for these suspensions. mixing studies revealed that surface baffling and bottom profiling of the bioreactor and impeller speeds of 6 ...199218600977
diacylglycerol kinase from suspension cultured plant cells : characterization and subcellular localization.diacylglycerol kinase (adenosine 5'-triphosphate:1,2-diacylglycerol 3-phosphotransferase, ec, purified from suspension cultured catharanthus roseus cells (j wissing, s heim, kg wagner [1989] plant physiol 90: 1546-1551), was further characterized and its subcellular location was investigated. the enzyme revealed a complex dependency on lipids and surfactants; its activity was stimulated by certain phospholipids, with phosphatidylinositol and phosphatidylglycerol as the most effective ...199216668739
first field isolation of wound tumor virus from a plant host: minimal sequence divergence from the type strain isolated from an insect vector.a new strain of wound tumor virus (wtv) has been isolated from a periwinkle plant (catharanthus roseus) that was among several used as bait plants in a blueberry field. the 12 segments of double-stranded rna of the viral genome were isolated directly from infected tissue and found to have mobilities through agarose gels that were identical to those of the type strain wtv. coupled complementary dna (cdna) and polymerase chain reactions (pcr) primed with oligonucleotides complementary to the termi ...19911962460
large-scale (20 l) culture of surface-immobilized catharanthus roseus cells.surface-immobilized c. roseus cell cultures were grown in a 20-l modified airlift bioreactor operated at 0.51 vvm (kla approximately 8 h-1) under various gassing regimes [air, 2% (v/v) and 5% co2]. extracellular ammonium, phosphate, and nitrate ions as well as carbohydrate uptake and ph value of the medium were monitored together with on-line dissolved oxygen concentration, conductivity of the medium, and carbon dioxide production rate (cpr) of the cultures. cultures supplemented with 2% co2 sho ...19911367999
stimulated indole alkaloid release from catharanthus roseus immobilized cultures. initial studies.vacuolar sequestration of valuable secondary metabolites remains the major limitation to the use of immobilization technology for large scale plant-cell-based bioprocesses, which otherwise may be a more efficient culture system than suspension for this biomass. in this initial study, the release of indole alkaloids produced by immobilized catharanthus roseus cells cultured in zenk's alkaloid production medium was evaluated. unstimulated alkaloid release in immobilized cultures reached levels of ...19911367690
effect of culture process on alkaloid production by catharanthus roseus cells. ii. immobilized cultures.two processes for the production of indole alkaloids 2 l surface-immobilized bioreactor cultures of catharanthus roseus cells using zenk's alkaloid production medium (apm) were evaluated. the 1-stage process consisted of inoculating apm containing bioreactors and incubating for 15 d. the 2-stage process involved inoculating growth medium-containing bioreactors, growing the immobilized cultures for a certain period of time and subsequently replacing this medium with apm. the production stage whic ...19911367689
effect of culture process on alkaloid production by catharanthus roseus cells. i. suspension cultures.the processes for production of indole alkaloids in shake flask suspension cultures of catharanthus roseus cells using zenk's alkaloid production medium (apm) were evaluated. the 1-stage process consisted of inoculating apm and incubating for 15 days. the 2-stage process involved 6 d of cultivation in growth medium followed by 15 d of incubation in apm. growth, main nutrient consumption and alkaloid production were monitored. both culture processes produced approximately 20 g dw per 1 biomass. h ...19911367684
isolation and characterization of intergeneric somatic hybrids in the apocynaceae family.protoplasts were isolated from callus cultures of rauwolfia serpentina benth., rhazya stricta decaisne, and catharanthus roseus (l.) g. don, or from leaves of vinca minor l. protoplast isolation, culture, and fusion techniques as well as hybrid screening systems were developed for these species, and hybrids were obtained. hybrid combinations were rauwolfia + vinca, rauwolfia + catharanthus, rauwolfia + rhazya, and catharanthus + vinca. for hybrid isolation, the physiological complementation meth ...199124213445
strategies for the genetic manipulation of alkaloid-producing pathways in plants.increasingly, as a result of recent biochemical work, there exists a realistic possibility of taking a molecular genetic approach to the manipulation of alkaloid-producing pathways in plant tissue cultures. in the pathways forming indole alkaloids in catharanthus roseus, tropane alkaloids in datura and hyoscyamus species, and nicotine in nicotiana species, recent studies have identified a number of key enzymes and at least some of the factors that regulate their levels of activity. such knowledg ...199117226220
effect of near-ultraviolet light on alkaloid production in multiple shoot cultures of catharanthus roseus. 199117226190
expression of enzymatically active and correctly targeted strictosidine synthase in transgenic tobacco plants.strictosidine, a precursor to over 1000 indole alkaloids including the anti-tumor drugs vinblastine, vincristine, and camptothecin, is produced by the condensation of tryptamine and secologanin. strictosidine synthase, the enzyme responsible for this condensation, is the first committed step in the indole-alkaloid pathway. we have introduced a modified cdna encoding strictosidine synthase from catharanthus roseus (l.) don. (mcknight et al. 1990, nucl. acids res. 18, 4939) driven by the camv 35s ...199124186336
growth and stoichiometry of a catharanthus roseus cell suspension culture grown under nitrogen-limiting conditions.the uptake of carbohydrate and nitrate by catharanthus roseus cell suspension cultures was studied in relation to biomass production in shake flasks. biomass production was similar when using either 6, 12, 18, or 24 mm nitrate as the nitrogen source and 20 g l(-1) sucrose as the carbon source. in all cases, maximum biomass production was reached when carbohydrates were entirely consumer by the cells. apparent biomass yields, y(x/s) and y(x/n) were 0.49 g biomass g(-1) glucose equivalent and 0.23 ...199118604877
polyamines and the cell cycle of catharanthus roseus cells in culture.investigation was made on the effect of partial depletion of polyamines (pas), induced by treatment with inhibitors of the biosynthesis of pas, on the distribution of cells at each phase of the cell cycle in catharanthus roseus (l.) g. don. cells in suspension cultures, using flow cytometry. more cells treated with inhibitors of arginine decarboxylase (adc) and ornithine decarboxylase (odc) were accumulated in the g(1) phase than those in the control, while the treatment with an inhibitor of spe ...199116668290
preparation of sealed tonoplast and plasma-membrane vesicles from catharanthus roseus (l.) g. don. cells by free-flow electrophoresis.highly purified tonoplast and plasmamembrane vesicles were isolated from microsomes of catharanthus roseus (l.) g. don. by preparative free-flow electrophoresis. the relative amounts of tonoplast and plasma-membrane vesicles in the total microsomes varied with the ph of the grinding medium. the most electronegative fractions were identified as tonoplast using nitrate-inhibited, azide-resistant mg(2+)-atpase and pyrophosphatase activities as enzyme markers. the least electronegative fractions wer ...199124194236
regulation of dna synthesis and cell division by polyamines in catharanthus roseus suspension cultures.various inhibitors of polyamine biosynthesis were used to study the role of polyamines in dna synthesis and cell division in suspension cultures of catharanthus roseus (l.) g. don. arginine decarboxylase (adc; ec was the major enzyme responsible for putrescine production. dl α-difluoromethylarginine inhibited adc activity, cellular putrescine content, dna synthesis, and cell division. the effect was reversible by exogenous putrescine. ornithine decarboxylase (odc; ec activity ...199124221490
secondary metabolite biosynthesis in cultured cells of catharanthus roseus (l.) g. don immobilized by adhesion to glass fibres.suspension-cultured cells of catharanthus roseus (l.) g. don were immobilized on glass fibre mats and cultivated in shake flasks. the highly-aggregated immobilized cells exhibited a slower growth rate and accumulated reduced levels of tryptamine and indole alkaloids, represented by catharanthine and ajmalicine, in comparison to cells in suspension. the increased total protein synthesis in immobilized cells suggests a diversion of the primary metabolic flux toward protein biosynthetic pathways an ...19911367318
induction of catharanthine synthesis and stimulation of major indole alkaloids production by catharanthus roseus cells under non-growth-altering treatment with pythium vexans extracts.a catharanthus roseus cell line was selected that synthesised catharanthine exclusively under elicitation.from the first day of culture, treatment with very low concentrations of a pythium extract did not alter the growth of the suspension but, within 24 hours, induced the synthesis of catharanthine and stimulated the production of ajmalicine. kinetic analysis showed that serpentine then began to accumulate and that all of these effects lasted more than 7 days. elicitation also induced changes i ...199124226159
plant cell growth under different levels of oxygen and carbon experimental system, in which gases of known composition were passed through flasks, was used to systematically study the effects of oxygen and carbon dioxide on plant cell growth. as expected, oxygen limiting conditions resulted in suppressed growth of catharanthus roseus cultures. oxygen limitations did not alter the amount of cell mass produced per gram of sugar consumed which suggests that the production of fermentative metabolites was limited. varying levels of carbon dioxide were observ ...199124226158
an investigation into the role of initial k(l)a on the growth and alkaloid accumulation by cultures of catharanthus roseus.the effect of initial k(l)a on the batch culture of catharanthus roseus id1 in a 12.5-l bioreactor has been examined. optimum k(l)a values were found for both growth and alkaloid accumulation. different sparger designs were used to alter the k(l)a values. high k(l)a values caused increased aggregation of the cultures, depressed biomass yields, and altered patterns of alkaloid accumulation.199118597378
isolation of genes that are preferentially expressed at the g(1)/s boundary during the cell cycle in synchronized cultures of catharanthus roseus cells.a cdna library was screened for genes that may be involved in the progression of the cell cycle of cells of higher plants. the catharanthus roseus l. (g) don. cells were synchronized by the double phosphate starvation method, and a lambdagt11 cdna library was prepared using poly(a)(+) rna from cells in the s phase of the cell cycle. two independent sequences, cyc02 and cyc07, were identified by differential screening. the levels of cyc02 and cyc07 mrnas increased dramatically, but transiently, a ...199116667998
a reversible carrier mediates the transport of malate at the tonoplast of catharanthus roseus cells.the conditions of malate transport were defined in tonoplast vesicles purified from a microsomal homogenate of catharanthus roseus cells by preparative free-flow electrophoresis. isolated vesicles exhibited malate transport when the membranes were prepared by grinding the cells in a homogenisation medium only buffered in the acidic ph range. by using vesicles energized artificially by an imposed ph gradient (acid interior), it was shown that malate is actively accumulated in response to the gene ...19902262004
identification of non-equilibrium glycolytic reactions in suspension-cultured plant cells.levels of all enzymes and metabolites involved in glycolysis were determined in suspension-cultured catharanthus roseus cells. from both the maximum catalytic activities of the enzymes and comparisons of mass-action ratios with the apparent equilibrium constants for the reactions, it is concluded that the reactions catalysed by hexokinase, fructokinase, phosphofructokinase and pyruvate kinase are far from equilibrium, whereas the other reactions including that catalysed by pyrophosphate-fructose ...19902223831
isolation and characterization of a 2-oxoglutarate dependent dioxygenase involved in the second-to-last step in vindoline biosynthesis.young leaves from catharanthus roseus plants contain the enzymes which convert the monoterpenoid indole alkaloid, tabersonine by three hydroxylations, two methylations, and one acetylation step to vindoline. a novel direct enzyme assay has been developed for a hydroxylase involved in vindoline biosynthesis, which catalyzes the c4-hydroxylation of 2,3-dihydro-3-hydroxy-n(1)-methyltabersonine to the 3,4-dihydroxy derivative. the enzyme showed an absolute requirement for 2-oxoglutarate and enzymati ...199016667836
nucleotide sequence of a cdna encoding the vacuolar protein strictosidine synthase from catharanthus roseus. 19902395663
effects of long-term preservation on growth and productivity of panax ginseng and catharanthus roseus cell cultures.cell cultures of panax ginseng and catharanthus roseus producing secondary metabolites were preserved in liquid nitrogen or under mineral oil for six months. the growth behaviour and the ability of the cultures to produce ginsenosides or indole alkaloids were measured after a recovery period and compared with cultures maintained by frequent subcultivation during the same period. neither growth kinetics nor the degree of vacuolization during growth were affected by the long term preservation. som ...199024226696
specific differences in tolerance to exogenous berberine among plant cell cultures.the tolerance of plant cells to exogenously administered berberine, an antimicrobial isoquinoline alkaloid, was studied using berberine-producing and nonproducing cell suspension cultures. both coptis japonica and thalictrum flavum cells, which have an intrinsic ability to synthesize berberine, took up exogenous berberine from the culture medium by an energy-requiring active transport to accumulate it exclusively in vacuoles. by contrast, t. minus cells, which excrete indigenous berberine mostly ...199024226596
identification of indole alkaloids of catharanthus roseus with liquid chromatography/mass spectrometry using collision-induced dissociation with the thermospray ion repeller.fragmentation of protonated molecular ions produced from catharanthine, tabersonine, ajmalicine and serpentine in a high-performance liquid chromatography (hplc) thermospray ion source was studied. collision-induced dissociation (cid) of the compounds was achieved by merely increasing the repeller potential; i.e. no discharge current was applied and filament was not on. proportion of fragments to the protonated molecular ions increased with the potential at the 180-350 v range studied, but overa ...19902400851
indole alkaloid formation by catharanthus roseus cells in a biofilm reactor.catharanthus roseus cells producing indole alkaloids were grown in the form of a biofilm. production medium was circulated through the reactor parallel to the upper surface of the horizontal biofilm. sugar consumption and indole alkaloid formation were followed to compare the performance of cultures with different biofilm thicknesses. dissolved oxygen concentrations gradients within the biofilms were determined at the end of each run. rna and protein content of the cells in the upper and lower l ...20061370003
proton/phosphate stoichiometry in uptake of inorganic phosphate by cultured cells of catharanthus roseus (l.) g. don.upon absorption of phosphate, cultured cells of catharanthus roseus (l.) g. don caused a rapid alkalinization of the medium in which they were suspended. the alkalinization continued until the added phosphate was completely exhausted from the medium, at which time the ph of the medium started to drop sharply toward the original ph value. phosphate exposure caused the ph of the medium to increase from ph 3.5 to values as high as 5.8, while the rate of phosphate uptake was constant throughout (10- ...199016667491
effect of thermal power plant emissions on catharanthus roseus l. 19902354262
purification and characterization of acetylcoenzyme a: deacetylvindoline 4-o-acetyltransferase from catharanthus roseus.the enzyme acetylcoenzyme a:deacetylvindoline 4-o-acetyltransferase (ec 2.3.1.-) (dat), which catalyzes the final step in vindoline biosynthesis in catharanthus roseus, was purified 3300-fold using ammonium sulfate precipitation followed by gel filtration, anion exchange, hydroxyapatite, and affinity chromatographies. sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) of the purified dat showed the presence of two major proteins having mr values of 33,000 and 21,000, whereas na ...19902350183
gas chromatographic-mass spectrometric analysis of major indole alkaloids of catharanthus roseus. 19902355069
development of a strategy to control the dissolved concentrations of oxygen and carbon dioxide at constant shear in a plant cell examine the effects of volatile components on plant cell growth, a bioreactor control system was developed to simultaneously control the dissolved concentrations of both oxygen and carbon dioxide. the first step in this work was to develop a mathematical model to account for gas-liquid mass transfer; biological utilization and production of o(2) and co(2); and the series of chemical reactions of co(2) in water. using this model and dynamic measurements for dissolved o(2) and co(2), it was obs ...199018592487
photochemical one-pot synthesis of vinblastine and vincristine.the naturally occurring cytostatic dimer alkaloids vinblastine 1 and vincristine 2 were photochemically synthesized in slightly acidic aqueous solution from the monomer alkaloids catharanthine 3 and vindoline 4. multi-centre reactions should obviously be involved and some of the principal photochemistry-associated phenomena here discussed are quite likely to be characteristic even to the biosynthetic reactions yielding vinblastine 1 and vincristine 2 in the cells of catharanthus roseus.19902367548
characterization of tonoplast-enriched vesicles isolated by gradient density fractionation of suspension-cultured cells.a tonoplast-enriched microsomal fraction was isolated from catharanthus roseus cells. it was characterized by structural and functional criteria. this fraction presented a homogeneous size distribution as shown by quasi-elastic light scattering and a homogeneous density on self-generated gradients of percoll. the mean diameter of the vesicles was estimated to be 0.30 micron and the buoyant density around 1.04 g/ml. sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of its polypep ...19902139317
isolation of catharanthus alkaloids by solid-phase extraction and semipreparative hplc.a combination of moderate-pressure chromatography on c18 sorbent and preparative hplc is developed for rapid isolation of alkaloids from catharanthus roseus. the procedure is optimized for vindoline and catharanthine with respective yields of 3 and 2 mg per 1 g of dried leaves of the plant. the methodology is also applied for identification of the above and other alkaloids from cultured plant cells.19902079546
development of bioreactors for the culture of surface immobilized plant cells.the scaleup of the technique of plant cell surface immobilization was performed successfully in specifically designed laboratory size bioreactors. the immobilizing matrix was formed into a vertically wound spiral providing for a high immobilizing area-to-volume ratio (0.8-1.2 cm(-1)). a modified airlift and a mechanically stirred vessel delivered a best bioreactor performance characterized by low biomass frothing and highly efficient plant cell attachment and retention (>or=96%). the growth of c ...199018592566
production of indole alkaloids by surface immobilized c. roseus cells.a technique was developed to surface immobilize plant cells and was scaled up in laboratory size bioreactors. this technique was shown not to hinder the biosynthetic potential of catharanthus roseus immobilized cells and to induce a partial release (300 microg/l) of serpentine into the culture medium contrary to suspension cultured cells. the release pattern seemed to follow the biosynthesis trends of the product. this release mechanism could be stimulated by a factor of 10 within 2 h by increas ...199018592562
purification of acetyl-coa: 17-o-deacetylvindoline 17-o-acetyltransferase from catharanthus roseus leaves.the enzyme acetyl-coa: 17-o-deacetylvindoline 17-o-acetyltransferase which terminates vindoline biosynthesis has been isolated from catharanthus roseus leaves, further characterized and purified to homogeneity by three step column chromatography and subsequent preparative isoelectric focusing. kinetic properties concerning the enzyme reaction are discussed. five multiple forms of the acetyl-transferase could be observed, each consisting of two subunits. this enzyme is now the best characterized ...199024232684
optimal temperature control for a structured model of plant cell culture.this article calculates optimal open-loop temperature trajectories that maximize the average rate of product synthesis of a plant cell culture. it uses a previously published five-state mathematical model which describes the growth and product synthesis of a batch plant cell suspension culture of catharanthus roseus under temperature control. the optimal open-loop temperatures maximize the final product concentration for predefined fermentation periods. a single switch in temperature is shown by ...199018592517
alkaloid secondary products from catharanthus roseus cell suspension.plant cell culture, the growth of plant cells on solid medium or in liquid, was originally used to study the physiology and biochemistry of plants without the complication of the whole plant. however, it was soon found that plant cell cultures were often capable of producing compounds characteristic of the original plant. of particular interest were those compounds known as secondary products. secondary products are poorly defined, but in general are products that are not essential for growth, b ...199021390635
monoclonal antibodies to bis-indole alkaloids of catharanthus roseus and their use in enzyme-linked immuno-sorbent-assays.high affinity monoclonal antibodies directed against bis-indole alkaloids from catharanthus roseus were produced. once characterized, they were used to develop sensitive enzyme-linked-immuno-sorbent-assays, enabling us to determine minute quantities of alkaloids related to vinblastine in plant material.19901366691
carrier-mediated uptake of 1-(malonylamino)cyclopropane-1-carboxylic acid in vacuoles isolated from catharanthus roseus cells.the uptake of 1-(malonylamino)cyclopropane-1-carboxylic acid (macc), the conjugated form of the ethylene precursor, into vacuoles isolated from catharanthus roseus cells has been studied by silicone layer floatation filtering. the transport across the tonoplast of macc is stimulated fourfold by 5 millimolar mgatp, has a k(m) of about 2 millimolar, an optimum ph around 7, and an optimum temperature at 30 degrees c. several effectors known to inhibit atpase (n,n'-dicyclohexylcarbodiimide) and to c ...198916667182
how suspension cultures of catharanthus roseus respond to oxygen limitation: small-scale tests with applications to large-scale cultures.the effect of oxygen supply on the growth of suspension cultures of catharanthus roseus in erlenmeyer flasks was investigated. below a critical oxygen supply rate the culture could not survive. by increasing the oxygen supply, a point is reached where the culture survives but no growth is possible. at higher oxygen supply rates there is a regime where both growth rate and the maximum biomass concentration increase with oxygen supply. eventually there comes a point where no further increase in bi ...198918588199
electrochemical detection of indole alkaloids of catharanthus roseus in high-performance liquid chromatography.hydrodynamic voltammograms for indole and five indole alkaloids with different amino functions were obtained in order to evaluate the applicability of high-performance liquid chromatography (hplc) with coulometric detection to these compounds. with the exception of serpentine, which has a quaternary nitrogen in its structure, all the compounds were oxidised and gave net signals of greater than 25 na pmol(-1) at potentials of between +0.2 and +0.85 v versus a solid pd electrode in an acetate-buff ...19892619069
modification of catharanthus roseus alkaloids: a lactone derived from 17-deacetylvinblastine.a spirolactone with anti-tumor activity is formed during the reaction of paraformaldehyde with 17-deacetylvinblastine. the compound was identified by nmr techniques. the chemotherapeutic activity was assessed.19892813571
the degrees of polymerization and n-acetylation of chitosan determine its ability to elicit callose formation in suspension cells and protoplasts of catharanthus roseus.partially and fully deacetylated chitosan fragments and oligomers were compared for their potency to elicit formation of the 1.3-β-glucan callose in suspension-cultured cells and protoplasts of catharanthus roseus (line 385). chitosan oligomers induced little callose formation, while callose synthesis increased with the degree of polymerization of chitosan up to several thousand corresponding to a molecular mass near 10(6) da. at a comparable degree of polymerization, partially n-acetylated chit ...198924212905
diffusible factors essential for epidermal cell redifferentiaion in catharanthus roseus.during postgenital tissue fusions, some plant epidermal cells redifferentiate into parenchyma, a different cell type. diffusible factors cause this response in the fusing gynoecium of the madagascar periwinkle (catharanthus roseus). surgical manipulations of the gynoecium showed that epidermal cells from normally nonfusing surfaces could trasmit and respond to the diffusible factors. furthermore, the diffusible fators could be trapped in agar-impregnated barriers, as shown by the redifferentiati ...198917769401
mass spectral evidence of the occurrence of vindoline in heterotrophic cultures of catharanthus roseus cells.vindoline concentrations in the leaves of 70 catharanthus roseus of 3 cultivars were analyzed by hplc, and 3 plants were selected for starting callus cultures on different media. when the initial calli were analyzed using a vindoline-specific ria, the assay suggested a vindoline content of about 10 (-5)% dry weight for one-third of the first 60 cultures examined. due to the unexpectedly high incidence of vindoline-positive calli, the screening programme was discontinued and efforts were concentr ...198917262331
phase-specific polypeptides and poly(a) rnas during the cell cycle in synchronous cultures of catharanthus roseus cells.this study shows an overall analysis of gene expression during the cell cycle in synchronous suspension cultures of catharanthus roseus cells. first, the cellular cytoplasmic proteins were fractionated by two-dimensional gel electrophoresis and visualized by staining with silver. seventeen polypeptides showed qualitative or quantitative changes during the cell cycle. second, the rates of synthesis of cytoplasmic proteins were also investigated by autoradiography by labeling cells with [(35)s]met ...198916666641
genetic transformation ofcatharanthus roseus g. don byagrobacterium rhizogenes.catharanthus roseus plantlets were inoculated with differentagrobacterium rhizogenes strains. this plant species is known to produce secondary metabolites and axenic hairy-root cultures are an alternative to extraction of plant tissue for the compounds which are synthesized in roots. hairy root lines were established from inoculations with the agropine strain 15834 and transformed plants were obtained after spontaneous regeneration. phenotypic alterations of both the root system and the aerial p ...198924232985
assay of strictosidine synthase from plant cell cultures by high-performance liquid hplc assay is described for the enzyme strictosidine synthase in which the formation of strictosidine and the decrease of tryptamine can be followed at the same time. in cell cultures of catharanthus roseus significant amounts of strictosidine glucosidase activity were detected. in crude preparations, the strictosidine synthase reaction is therefore best measured by the secologanin-dependent decrease of tryptamine. in this way, the specific synthase activity in a cell free extract was found t ...19892742131
regulation of vacuolar ph of plant cells: ii. a p nmr study of the modifications of vacuolar ph in isolated vacuoles induced by proton pumping and cation/h exchanges.the vacuolar ph and the trans-tonoplast deltaph modifications induced by the activity of the two proton pumps h(+)-atpase and h(+)-ppase and by the proton exchanges catalyzed by the na(+)/h(+) and ca(2+)/h(+) antiports at the tonoplast of isolated intact vacuoles prepared from catharanthus roseus cells enriched in inorganic phosphate (y mathieu et al 1988 plant physiol [in press]) were measured using the (31)p nmr technique. the h(+)-atpase induced an intravacuolar acidification as large as 0.8 ...198916666525
regulation of vacuolar ph of plant cells: i. isolation and properties of vacuoles suitable for p nmr studies.for the first time, the (31)p nuclear magnetic resonance technique has been used to study the properties of isolated vacuoles of plant cells, namely the vacuolar ph and the inorganic phosphate content. catharanthus roseus cells incubated for 15 hours on a culture medium enriched with 10 millimolar inorganic phosphate accumulated large amounts of inorganic phosphate in their vacuoles. vacuolar phosphate ions were largely retained in the vacuoles when protoplasts were prepared from the cells and v ...198916666513
adhesion of catharanthus roseus cells to surfaces: effect of substrate hydrophobicity. 198818587809
diffusion of sucrose and yohimbine in calcium alginate gel beads with or without entrapped plant cells.the diffusion characteristics of sucrose, a nutrient, and yohimbine, a secondary metabolite, in alginate gel beads, with or without entrapped periwinkle (catharanthus roseus) or apple (malus domestica) cells, were investigated. effective diffusivities of both solutes in the gel beads were determined by two different methods from transient concentration changes in well-stirred solutions where the beads were suspended. the linear plot method developed in this work is easy to use and requires no da ...198818587800
bioreactor considerations for secondary metabolite production from plant cell tissue culture: indole alkaloids from catharanthus roseus.batch shake flask studies with catharanthus roseus demonstrated that alkaloid production commenced only after growth had slowed or ceased. to obtain high alkaloid productivities for extended periods, a hormone-free production medium was used. to develop a readily scalable process, both immobilized and suspended cell systems were studied. in the immobilized cell systems, growth, glucose utilization, and alkaloid production were suppressed; for the case of membrane entrapped cells this suppression ...198818584698
characterization of alkaloid uptake by catharanthus roseus (l.) g. don protoplasts.the accumulation of alkaloids by protoplasts of catharanthus roseus (l.) g. don var. little bright eye was studied to determine the specificity of uptake and the role of ion trapping in the storage of alkaloids. accumulation of the indole alkaloids vindoline, ajmalicine, tabersonine, and vinblastine was found to be biphasic, with an initial burst of uptake followed by a slow, prolonged phase of accumulation. the concentration and ph dependence of the initial burst of uptake for vindoline suggest ...198816666154
stimulation of indole alkaloid content in vanadium-treated catharanthus roseus suspension cultures.addition of vanadyl sulphate to cell suspensions of catharanthus roseus was found to increase ajmalicine, catharanthine, and tryptamine levels. up to 500 microg/g dry weight catharanthine and 131.0 microg/g dry weight ajmalicine were detected in vanadyl sulphate-treated cells. this represents an approximate increase of 50% over control levels. this stimulation was found to be dependent upon the concentration of vanadyl sulphate administered and upon the cell age. high tryptamine levels were not ...198817265225
developmental regulation of enzymes of indole alkaloid biosynthesis in catharanthus roseus.developing seedlings of catharanthus roseus were analyzed for appearance of tryptophan decarboxylase (tdc), strictosidine synthase (ss), n-methyltransferase (nmt) and o-acetyltransferase (dat) enzyme activities. ss enzyme activity appeared early after germination and was present throughout most of the developmental study. tdc activity was highly regulated and peaked over a 48 hour period achieving a maximum by day of 5 of seedling development. both tdc and ss were present in all tissues of the s ...198816665928
formation of vinblastine in multiple shoot culture of catharanthus roseus. 19883375331
auxin induces rapid changes in phosphatidylinositol metabolites.the plant growth-hormone auxin (indole-3-acetic acid, iaa) is involved in regulating such diverse processes as cell elongation, cell division and differentiation. the sequence of events leading to the various phenomena is still poorly understood. both changes in extra- and intracellular ph (refs 1-4) and selective transcription are known to be induced by auxin. evidence for auxin receptors at the plasmalemma membrane has been reported, but the signal transduction pathway is not known, for this n ...19883257546
induced net ca(2+) uptake and callose biosynthesis in suspension-cultured plant suspension-cultured cells of glycine max and catharanthus roseus, marked callose synthesis can be induced by digitonin and chitosan. leakage of a limited pool of electrolytes precedes callose formation, k(+) representing the major cation lost. poly-l-ornithine, as well as the ionophores a 23187 and ionomycin, also induces some callose synthesis but to a lesser extent. digitonin increases the net uptake of ca(2+) from the external buffer with a time course parallel to callose synthesis but lag ...198824226184
characterization of a novel n-methyltransferase (nmt) from catharanthus roseus plants : detection of nmt and other enzymes of the indole alkaloid biosynthetic pathway in different cell suspension culture systems.young leaves from catharanthus roseus plants contain a novel n-methyltransferase which transfers the methyl group from s-adenosyl-l-methionine specifically to position 1 of (2r, 3r)-2,3-dihydro-3-hydroxytabersonine, producing the n-methylated product. the enzyme shows a high degree of specificity toward substrates containing a reduced double bond at position 2,3 of tabersonine derivatives but the more substituted n-desmethyldeacetylvindoline did not act as a substrate. the enzyme catalyses the t ...198724248932
subcellular localization of enzymes involved in indole alkaloid biosynthesis in catharanthus roseus.the subcellular localization of enzymes involved in indole alkaloid biosynthesis in leaves of catharanthus roseus has been investigated. tryptophan decarboxylase and strictosidine synthase which together produce strictosidine, the first indole alkaloid of this pathway, are both cytoplasmic enzymes. s-adenosyl-l-methionine: 16-methoxy-2,3-dihydro-3-hydroxytabersonine-n-methyltransferase which catalyses the third to last step in vindoline biosynthesis could be localized in the chloroplasts of cath ...198716665811
immunoanalytical methods for screening vindoline from catharanthus roseus cell cultures. 19873444865
alkaloid production in root and shoot cultures of catharanthus roseus.root and shoot cultures were induced from seedlings of catharanthus roseus. root cultures and cell suspension cultures derived from the root cultures showed similar alkaloid spectra to the roots of intact plants. the alkaloid spectra of shoot cultures and the aerial parts of intact plants were similar to each other but different from those of root and suspension cultures. illumination affected the alkaloid spectra of shoot cultures. shoot cultures produced 3',4'anhydrovinblastine, an immediate p ...198717269072
stimulation of indole alkaloid production in cell suspension cultures of catharanthus roseus by abscisic acid.when added to suspension cultures of catharanthus roseus, abscisic acid (aba) stimulated intracellular accumulation of the indole alkaloids catharanthine and ajmalicine in both flask and 30 litre fermenter-scale systems. the response varied, and depended upon the cell line, the concentration and source of the aba, and the growth phase at which the cells were treated. precise timing of aba addition to cells in a 301 fermenter resulted in a catharanthine yield of 85.25 mg/l after 10 days of cultiv ...198717269070
ajmalicine, serpentine, and catharanthine accumulation in catharanthus roseus bioreactor cultures.a 141, stirred-tank bioreactor was used to investigate the effect of 7% glucose solutions on catharanthus roseus suspension cultures. measurement of oxygen uptake rate indicated that alkaloid accumulation occurred primarily during a 20-day transition period between growth-oriented metabolism and maintenance-oriented metabolism. exposure of the cells to light during this period stimulated catharanthine accumulation and triggered a switch from ajmalicine accumulation to serpentine accumulation. in ...198717269046
time-course studies in indole alkaloid accumulation and changes in tryptophan decarboxylase and strictosidine synthase activities: a comparison in three strains of catharanthus roseus cells.three different strains of catharanthus roseus cells were compared during one subculture with regard to tryptophan, tryptamine, ajmalicine, serpentine contents and tryptophane decarboxylase (tdc) (4) and strictosidine synthase activities. the strains differed greatly in their accumulation of tryptamine and alkaloid. the tdc of all three strains showed the highest activity during the growth phase and declined sharply at the end of this phase. on the contrary, strictosidine synthase activity was t ...198717269044
alkaloid formation by habituated and tumorous cell suspension cultures of catharanthus roseus.habituated and tumorous catharanthus roseus cells grown in the absence of hormones accumulated indole alkaloids. total alkaloids and alkaloid pattern were the same when cells were cultured in medium without hormones or in alkaloid production medium with and without indole acetic acid. treatment of cells with pythium homogenate as elicitor did not increase total alkaloids or change the pattern of alkaloids produced. when either habituated or tumorous cells were grown in 1b5 medium after gamborg e ...198724248757
increased accumulation of indole alkaloids by some cell lines of catharanthus roseus in response to addition of vanadyl sulphate.vanadyl sulphate (10-500 mg/l), when added to cell suspension cultures of catharanthus roseus stimulated increased intracellular accumulation of catharanthine and ajmalicine. this response was demonstrated in both flask and fermenter (30 litre) systems. the response varied, and depended upon cell line, concentration of vanadyl sulphate and the stage of the growth phase at which the cells were treated. this process has the potential to increase the yield and reduce the production time for commerc ...198724248497
regulation of product synthesis in cell cultures of catharanthus roseus. effect of culture temperature.a three year old, alkaloid producing cell line of catharanthus roseus, maintained at 25°c, was grown on 2% sucrose at various temperatures from 10° to 45°c. growth rates were maximal at 35°c but declined rapidly above 35°c and below 25°c. maximum serpentine yields reached a peak at between 20°c and 25°c and fell sharply above and below these temperatures, while ajmalicine showed a sharp peak of accumulation at 20°c. the variable serpentine/ajmalicine ratio at different growth temperatures sugges ...198624248397
the proton-pumps at the plasmalemma of catharanthus roseus cells.cultured catharanthus roseus cells exhibit transmembrane ferricyanide (fic) reduction which is associated with a proton translocation and a decrease in the atp content of the cells. the h+ efflux and the atp consumption may be counteracted by vanadate, a specific inhibitor of the atpase activity, and by na2wo4 which prevents fic reduction. from these data it is concluded that the redox chain could be coupled with atp hydrolysis for electrogenic proton extrusion which may involve a redox control ...19862878688
does a proton-pumping atpase exist in the tonoplast?in order to account for the accumulation of metabolites in plant vacuoles, the existence of a proton-pumping atpase has been widely suggested in the literature. the demonstration of such a tonoplast-bound atpase was merely based on the characterization of a nitrate-sensitive microsomal fraction. in some examples, this atpase activity has been evidenced on vacuole preparations obtained under conditions which were criticized by boller. the application of the reverse phase high-performance liquid c ...19862878687
cytoplasmic ph regulation in acer pseudoplatanus cells: i. a p nmr description of acid-load effects.modifications of cytoplasmic ph in acer pseudoplatanus l. cells cultivated in suspension have been induced by acid-loads and studied by using (31)p nuclear magnetic resonance spectroscopy. the initial drop of cytoplasmic ph, observed in the first minutes of exposure to weak lipophilic acids, was followed by a slow recovery to reach a plateau phase with a ph value lower than the initial one. conversely, removal of the acid led to a sharp increase of cytoplasmic ph with in most cases an overshoot ...198616665119
growth kinetics of dioscorea deltoidea and catharanthus roseus in batch culture.sugar-limited batch growth of dioscorea deltoidea and catharanthus roseus plant cell cultures was studied in a 14-l stirred tank fermentor. with dissolved oxygen concentration monitored and maintained at nonlimiting levels, growth rates and ratios of dry weight to fresh weight were found to be strongly influenced by sugar concentration. linear relationships between respiration rate and growth rate were observed, and respiration rate was found to drop to a maintenance level after sugar had been f ...198618553873
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