PMID(sorted ascending)
catharanthus roseus genes regulated differentially by mollicute infections.a differential display of mrnas was used to isolate periwinkle cdnas differentially expressed following infection with one of three mollicutes: spiroplasma citri, candidatus phytoplasma aurantifolia, and stolbur phytoplasma. twenty-four differentially expressed cdnas were characterized by northern blots and sequence analysis. eight of them had homologies with genes in databanks coding for proteins involved in photosynthesis, sugar transport, response to stress, or pathways of phytosterol synthes ...200111204786
[differential accumulation of the new high-affinity phosphate transporter candidated gene fragment in rice roots in response to phosphorus deficiency stress].phosphate is a major constraint to crop production, and phosphate uptake in plant is mainly by high-affinity phosphate transporter under phosphate deficiency condition. using rt-pcr, a 1,178 bp phosphate transporter gene fragment ojpt1 was cloned from roots of jingxi17 (oryza sativa l. ssp. japanica) supplied with no phosphate. the comparison of this sequence with ones in genbank indicated that it shared about 70% similarity at amino acid level with other phosphate transporters in higher plants, ...200111233258
monitoring the production yields of vincristine and vinblastine in catharanthus roseus from somatic embryogenesis. semiquantitative determination by flow-injection electrospray ionization mass spectrometry.a semiquantitative determination of two bis-indole antitumor alkaloids, vincristine and vinblastine, has been performed by flow-injection electrospray ionization mass spectrometric analysis of the extracts of catharanthus roseus. leaves and flowers of two different phenotypes (pink flower and white flower) obtained from somatic embryogenesis were thus examined and compared with the field-grown mother plant. different amounts of vincristine and vinblastine were detected depending on the examined ...200111241768
pleiotropic morphological and abiotic stress resistance phenotypes of the hyper-abscisic acid producing abo- mutant in the periwinkle catharanthus roseus.the pleiotropic properties of a abo abo (abo-) gamma-ray induced mutant of catharanthus roseus cv. nirmal, selected among the m2 generation seeds for ability to germinate at 45 degrees c, are described. the mutant produced seeds possessing tricotyledonous embryos, unlike the typically dicotyledonous embryos present in the wild type abo+ seeds. in comparison to abo+ adults, the mutant plants had short stature and lanceolate leaves. the vascular bundles in the leaves and stem were poorly developed ...200111255514
selective interaction of triazole derivatives with dwf4, a cytochrome p450 monooxygenase of the brassinosteroid biosynthetic pathway, correlates with brassinosteroid deficiency in planta.brassinazole, a synthetic chemical developed in our laboratory, is a triazole-type brassinosteroid biosynthesis inhibitor that induces dwarfism in various plant species. the target sites of brassinazole were investigated by chemical analyses of endogenous brassinosteroids (brs) in brassinazole-treated catharanthus roseus cells. the levels of castasterone and brassinolide in brassinazole-treated plant cells were less than 6% of the levels in untreated cells. in contrast, campestanol and 6-oxocamp ...200111319239
selection of fungal elicitors to increase indole alkaloid accumulation in catharanthus roseus suspension cell culture.various fungal elicitors derived from 12 fungi were tested to improve indole alkaloid production in catharanthus roseus cell suspension cultures. results show that different fungal mycelium homogenates stimulate different kinds of indole alkaloid (ajmalicine, serpentine and catharanthine) accumulation, which ranged from 2- to 5-fold higher than the control. some fungal culture filtrates also efficiently elicited the biosynthesis of different indole alkaloids. the optimal elicitor addition and ex ...200111339951
enhanced catharanthine production in catharanthus roseus cell cultures by combined elicitor treatment in shake flasks and bioreactors.chemical and fungal elicitors were added to catharanthus roseus cell suspension cultures so as to improve the production of indole alkaloids. a synergistic effect on alkaloid accumulation was observed in c. roseus cell cultures when treated with some combined elicitors of fungal preparations and chemicals. among them, the combination of tetramethyl amminium bromide and aspergillum niger mycelial homogenate gave the highest ajmalicine yield (63 mg l(-1)) and an improved catharanthine accumulation ...200111339952
phospholipase c activity from catharanthus roseus transformed roots: aluminum effect.the effect of aluminum on the activity of plc was examined in transformed roots from catharanthus roseus (l) g. don. when added in vitro to the reaction mixture, al inhibited the enzymatic activity in a concentration and time-dependent fashion. this effect is very similar for both activities (soluble and membrane-associated). when roots were treated in vivo with al 0.1 mm for short periods (0-4 h), plc activity was also inhibited. aluminum (1 mm) diminished root growth in approximately 50% when ...200111352226
catharanthus roseus g-box binding factors 1 and 2 act as repressors of strictosidine synthase gene expression in cell cultures.the enzyme encoded by the strictosidine synthase (str) gene catalyses a key step in the biosynthesis of therapeutically valuable terpenoid indole alkaloids. in catharanthus roseus the str gene was shown to be regulated by a wide variety of signals including auxin, methyl jasmonate and fungal elicitors in cell suspension cultures and by tissue-specific control in plant organs. the str promoter contains a functional g-box (cacgtg) cis-regulatory sequence. in order to understand better the mechanis ...200111352466
biotransformation of (+)- and (-)-camphorquinones by plant cultured cells.biotransformation of (+)- and (-)-camphorquinones with suspension plant cultured cells of nicotiana tabacum and catharanthus roseus was investigated. it was found that the plant cultured cells of n. tabacum and c. roseus reduce stereoselectively the carbonyl group of (+)- and (-)-camphorquinones to the corresponding alpha-keto alcohols.200111397432
molecular characterization of the salutaridinol 7-o-acetyltransferase involved in morphine biosynthesis in opium poppy papaver somniferum.salutaridinol 7-o-acetyltransferase (ec ) catalyzes the conversion of the phenanthrene alkaloid salutaridinol to salutaridinol-7-o-acetate, the immediate precursor of thebaine along the morphine biosynthetic pathway. we have isolated a cdna clone that corresponds to the internal amino acid sequences of the native enzyme purified from a cell suspension culture of opium poppy papaver somniferum. the recombinant enzyme acetylated the 7-hydroxyl moiety of salutaridinol in the presence of acetyl-coa. ...200111404355
effect of an antidiabetic extract of catharanthus roseus on enzymic activities in streptozotocin induced diabetic rats.hypoglycemic activity was detected in dichloromethane:methanol extract (1:1) of leaves and twigs of catharanthus roseus (family apocynaceae), a traditionally used medicinal plant, using streptozotocin (stz) induced diabetic rat model. extract at dose 500 mg/kg given orally for 7 and 15 days showed 48.6 and 57.6% hypoglycemic activity, respectively. prior treatment at the same dose for 30 days provided complete protection against stz challenge (75 mg/kg/i.p.x1). enzymic activities of glycogen syn ...200111448549
evaluation of antitumor activity of some medicinal plants of bangladesh by potato disk bioassay.the antitumor activity of the ethanolic extracts of 12 medicinal plants of bangladesh, including the vincristine-vinblastine producing catharanthus roseus was studied using the potato disk bioassay technique. among these, 10 plant extracts at 25.0-microgram/disc exhibited significant inhibition of crown gall tumors caused by agrobacterium tumefaciens.200011449504
herbal medicine in oncology.over the years cancer has been more complicated by 'wonder cures' than perhaps any other condition. remedies such as laetril, shark cartilage, high dose vitamins and many alternative medical practices have been used with little evidence of improvement and sometimes worsened outcome. it is disconcerting that attempts to scientifically discredit these treatments sometimes result in the development of conspiracy theories. however, some plants do contain anticancer agents, the vinca alkaloids (deriv ...200111458587
studies on plant-mediated fate of the explosives rdx and hmx.the fate of the explosives rdx and hmx on exposure to plants was investigated in 'natural' aquatic systems of myriophyllum aquaticum for 16 days, and in axenic hairy root cultures of catharanthus roseus for > or = 9 weeks. exposure levels were: hmx, 5 mg/l; and rdx, approximately 8 mg/l. exposure outcomes observed include: hmx, no transformation by aquatic plants, and minimal biological activity by axenic roots; and rdx, removal by both plant systems. in the case of rdx exposure to axenic roots, ...200111513416
effects of stress factors, bioregulators, and synthetic precursors on indole alkaloid production in compact callus clusters cultures of catharanthus roseus.compact callus cluster (ccc) cultures established from catharanthus roseus consist of cohesive callus aggregates displaying certain levels of cellular or tissue differentiation. ccc cultures synthesize about two-fold more indole alkaloids than normal dispersed-cell cultures. our studies here show that additions of kcl, mannitol, and a variety of synthetic precursors and bioregulators to the ccc cultures markedly improved indole alkaloid production and release of these alkaloids into the medium. ...200111525616
biotransformation of tryptamine and secologanin into plant terpenoid indole alkaloids by transgenic yeast.a transgenic saccharomyces cerevisiae was constructed containing the cdnas coding for strictosidine synthase (str) and strictosidine beta-glucosidase (sgd) from the medicinal plant catharanthus roseus. both enzymes are involved in the biosynthesis of terpenoid indole alkaloids. the yeast culture was found to express high levels of both enzymes. str activity was found both inside the cells (13.2 nkatal/g fresh weight) and in the medium (up to 25 nkatal/l medium), whereas sgd activity was present ...200111549013
aryltetralin lignans: chemistry, pharmacology and biotransformations.podophyllotoxin derivatives like etoposide 7a, etophos 7b, and teniposide 7c are used clinically as potent chemotherapeutic agents for a variety of tumors including small cell lung carcinoma, testicular cancer, and malignant lymphoma. these compounds derived from a series of modifications which converted podophyllotoxin 1a from an entity that interacted with tubulin and blocks mitosis to one that induced a block in late s or early g2 by interacting with topoisomerase ii. synthetic studies on pod ...200111562272
assay of 2,3-dihydroxybenzoic acid and related compounds in plant materials by high-performance liquid chromatography.salicylic acid and its putative biosynthetic precursors were assayed isocratically by rp-hplc with uv detection at 280 nm. optimum resolution was provided by an hplc mobile phase consisting of meoh-1% aqueous hoac (40:60, v/v), at ph 4. furthermore, for the analysis of 2,3-dihydroxybenzoic acid (2,3-dhba) in catharanthus roseus cell cultures after elicitation, a mobile phase consisting of acetonitrile-1% aqueous hcooh containing 0.25% trichloroacetic acid (1:5, v/v), at ph 2, was used. the recov ...200111572396
a new structural class of bisindole alkaloids from the seeds of catharanthus roseus: vingramine and methylvingramine.two new bisindole alkaloids, vingramine (1) and methylvingramine (2), were isolated from the seeds of catharanthus roseus, apocynaceae. the structures were determined by hrfabms as well as one- and two-dimensional nmr experiments. they possess a new bisindole skeleton involving an indole alkaloid part b with loss of 5',6'-ethylene, a c7'-c16' linkage, a 14'-o-19'-tetrahydrofuran, and a n-4'-isobutyramide group. the 12-methyl vincorine part a and part b are connected via an 11,10'-biphenyl linkag ...199811672355
symmetry c18 column: a better choice for the analysis of indole alkaloids of catharanthus virtue of the different elution patterns of vindoline, catharanthine, vincristine and vinblastine present in the leaves of catharanthus roseus plants, a symmetry c18 column provided a better resolution for all of these compounds as compared with other c18 columns. the binary gradient system with a linear gradient profile, employed in a method developed using a symmetry c18 column, gave excellent peak symmetry, resolution and reproducibility. detection was performed at 220 nm which presented b ...200611705028
deracemization of racemic 4-pyridyl-1-ethanol by catharanthus roseus cell cultures.immobilized cells of catharanthus roseus synthesized (r)-4-pyridyl-1-ethanol from the corresponding racemate in 100% yield by stereoinversion of the (s)-alcohol in the racemate to the (r)-alcohol. furthermore, in the reduction of 4-acetylpyridine, we could synthesize both (r) and (s)-4-pyridyl-1-ethanol during a short or a long incubation.199811711075
antioxidant activity and phenolic compounds in selected herbs.the antioxidant capacities (oxygen radical absorbance capacity, orac) and total phenolic contents in extracts of 27 culinary herbs and 12 medicinal herbs were determined. the orac values and total phenolic contents for the medicinal herbs ranged from 1.88 to 22.30 micromol of trolox equivalents (te)/g of fresh weight and 0.23 to 2.85 mg of gallic acid equivalents (gae)/g of fresh weight, respectively. origanum x majoricum, o. vulgare ssp. hirtum, and poliomintha longiflora have higher orac and p ...200111714298
geraniol 10-hydroxylase, a cytochrome p450 enzyme involved in terpenoid indole alkaloid biosynthesis.geraniol 10-hydroxylase (g10h) is a cytochrome p450 monooxygenase involved in the biosynthesis of iridoid monoterpenoids and several classes of monoterpenoid alkaloids found in a diverse range of plant species. catharanthus roseus (madagascar periwinkle) contains monoterpenoid indole alkaloids, several of which are pharmaceutically important. vinblastine and vincristine, for example, find widespread use as anti-cancer drugs. g10h is thought to play a key regulatory role in terpenoid indole alkal ...200111718718
isolation and partial characterization of norcoclaurine synthase, the first committed step in benzylisoquinoline alkaloid biosynthesis, from opium poppy.norcoclaurine synthase (ncs) catalyzes the condensation of dopamine and 4-hydroxyphenylacetaldehyde (4-hpaa) to yield norcoclaurine, the common precursor to all benzylisoquinoline alkaloids produced in plants. in opium poppy (papaver somniferum l.), ncs activity was detected in germinating seeds, young seedlings, and all mature plant organs, especially stems and roots. however, the highest levels of activity were found in cell-suspension cultures treated with a fungal elicitor. ncs activity was ...200111722126
cloning of a cdna encoding an e2 ubiquitin-conjugating enzyme from catharanthus roseus: expression analysis in plant organs and in response to hormones in cell suspensions.a novel cdna (crubie2) encoding ubiquitin-conjugating enzyme e2 was isolated from a catharanthus roseus cdna library. sequence comparison with arabidopsis thaliana e2 sequences revealed that crubie2 is a member of a new plant e2 sub-family. expression of crubie2 is repressed in developing organs and down-regulated by cytokinin suggesting that a decrease in the ubiquitin-dependent proteolytic pathway may take part in the regulation of alkaloid biosynthesis in c. roseus cell suspensions.200211741052
predicting the substrates of cloned plant o-methyltransferases.plant o-methyltransferases (omts) have important roles in secondary metabolite biosynthesis. sequencing projects and homology-based cloning strategies yield sequences for proteins with similarities to known omts, but the identification of the physiological substrates is not trivial. we investigated with a cdna cloned from catharanthus roseus the possibilities for predicting the substrates of omts, using the information from previous work and two newly identified motifs that were based on informa ...200211754938
t-dna activation tagging as a tool to isolate regulators of a metabolic pathway from a genetically non-tractable plant species.t-dna activation tagging is a method used to generate dominant mutations in plants or plant cells by the insertion of a t-dna which carries constitutive enhancer elements that can cause transcriptional activation of flanking plant genes. we applied this approach to the species catharanthus roseus (l.) g. don (madagascar periwinkle), in an attempt to isolate regulators of genes that are involved in the biosynthesis of secondary metabolites of the terpenoid indole alkaloid (tia) class. several tia ...200111817539
influence of fungal elicitors on production of ajmalicine by cell cultures of catharanthus roseus.suspension cultures of catharanthus roseus (c. roseus) were elicited with fungal cell wall fragments of aspergillus niger (a. niger), fusarium moniliforme (f. moniliforme), and trichoderma viride (t. viride). the effects of elicitor dosage, exposures time, and age of subculture on ajmalicine accumulation were studied. a higher concentration of elicitor extract responded positively to c. roseus suspension cultures. ajmalicine accumulation increased by about 3-fold when cells were treated with a. ...200211822914
application of immunoelectron microscopy techniques in the diagnosis of phytoplasma immunoelectron microscopy technique was applied to label chrysanthemum leuchanthemum phytoplasma in infected leaf tissues of chrysanthemum leuchanthemum l. and catharanthus roseus l. plants. specific monoclonal antibodies at different dilutions and secondary antimouse antibody conjugated with colloidal gold particles of different sizes were used. the monoclonal antibodies demonstrated their specificity against the antigen; immunocytological methods permitted the precise localization and ident ...200211921348
sequential solubilization of proteins precipitated with trichloroacetic acid in acetone from cultured catharanthus roseus cells yields 52% more spots after two-dimensional electrophoresis.sample preparation is still the most critical step in two-dimensional gel electrophoresis (2-de), and needs to be optimized for each type of sample. to analyze the proteome of the medicinal plant catharanthus roseus, we developed and evaluated a sequential solubilization procedure for the solubilization of proteins after precipitation in trichloroacetic acid and acetone. the procedure includes solubilization with a conventional urea buffer followed by a stronger solubilizing buffer containing th ...200111922593
heterologous expression of a rauvolfia cdna encoding strictosidine glucosidase, a biosynthetic key to over 2000 monoterpenoid indole alkaloids.strictosidine glucosidase (sg) is an enzyme that catalyses the second step in the biosynthesis of various classes of monoterpenoid indole alkaloids. based on the comparison of cdna sequences of sg from catharanthus roseus and raucaffricine glucosidase (rg) from rauvolfia serpentina, primers for rt-pcr were designed and the cdna encoding sg was cloned from r. serpentina cell suspension cultures. the active enzyme was expressed in escherichia coli and purified to homogeneity. analysis of its deduc ...200211985599
overexpression in catharanthus roseus hairy roots of a truncated hamster 3-hydroxy-3-methylglutaryl-coa reductase gene.catharanthus roseus (l.) g. don hairy roots harboring hamster 3-hydroxy-3-methylglutaryl-coa reductase (hmgr) (ec cdna without membrane-binding domain were evaluated by quantifying the levels of sterols and some indol-alkaloids. clone 236, with the highest hybridization signal, had the lowest soluble and microsomal hmgr activity and produced more ajmalicine and catharanthine than the control but had reduced campesterol concentration. clone 19, with low hybridization signal, had high so ...200211996224
inheritance of flower color in periwinkle: orange-red corolla and white eye.the commonly found flower colors in periwinkle (catharanthus roseus)--pink, white, red-eyed, and pale pink center--are reported to be governed by the epistatic interaction between four genes--a, r, w, and i. the mode of inheritance of an uncommon flower color, orange-red corolla and white eye, was studied by crossing an accession possessing this corolla color with a white flowered variety (nirmal). the phenotype of the f(1) plants and segregation data of f(2) and backcross generations suggested ...200212011178
biosynthesis of cholestanol in higher understand the early steps of c(27) brassinosteroid biosynthesis, metabolic experiments were performed with arabidopsis thaliana and nicotiana tabacum seedlings, and with cultured catharanthus roseus cells. [26, 28-2h(6)]campestanol, [26-2h(3)]cholesterol, and [26-2h(3)]cholestanol were administered to each plant, and the resulting metabolites were analyzed by gas chromatography-mass spectrometry. in all the species examined, [2h(3)]cholestanol was identified as a metabolite of [2h(6)]campest ...200212031446
effect of precursor feeding on alkaloid accumulation by a tryptophan decarboxylase over-expressing transgenic cell line t22 of catharanthus obtain more insight into the regulation of terpenoid indole alkaloid (tia) biosynthesis in catharanthus roseus (l.) g. don cell cultures and particularly to identify possible rate limiting steps, a transgenic cell line over-expressing tryptophan decarboxylase (tdc), and thus having a high level of tryptamine, was fed with various amounts of precursors (tryptophan, tryptamine, loganin and secologanin) in different time schedules and analyzed for tia production. when these precursors were added ...200212039535
screening of catharanthus roseus secondary metabolites by high-performance liquid chromatography.two direct hplc analytical methods for the screening of the major indole alkaloids of catharanthus roseus hairy roots and their iridoid precursors have been developed. photodiode array and fluorescence detection were performed. the separation was achieved on a reversed-phase c18 column. the first method allowed the separation of catharanthine, serpentine, tabersonine, vindoline, vinblastine, and vincristine in 20 min. ajmalicine, tryptophan, tryptamine and secologanine were separated using the s ...200212061566
antiproliferative activity of vietnamese medicinal plants.methanol, methanol-water (1:1) and water extracts were prepared from seventy-seven vietnamese medicinal plants and tested for their antiproliferative activities against human ht-1080 fibrosarcoma cells. among them, fifteen extracts including seven methanol extracts of caesalpinia sappan, catharanthus roseus, coscinium fenestratum, eurycoma longifolia, hydnophytum formicarum and streptocaulon juventas (collected at two areas), six methanol-water (1:1) extracts of cae. sappan, cat. roseus, co. fen ...200212081142
tryptophan decarboxylase from transformed roots of catharanthus roseus.tryptophan decarboxylase (tdc, ec from catharanthus roseus hairy roots was purified 80-fold. antibodies against tdc were obtained and they recognized only one protein of 55 kda in crude extracts from hairy root cultures. elicitation of transformed root cultures with macerozyme yielded a marked increase in tdc activity, which was accompanied by a similar increase in the amount of immunoreactive tdc protein. these results suggest that the alkaloid accumulation, produced by elicitation, r ...200212102544
the effect of ajmalicine spiking and resin addition timing on the production of indole alkaloids from catharanthus roseus cell cultures.the potential for the feedback inhibition of indole alkaloid synthesis was investigated by spiking suspension cultures of catharanthus roseus with 0, 9, or 18 mg/l ajmalicine on day 0. the production of ajmalicine, catharanthine, and serpentine were inhibited in a dose-dependent manner. the inhibition was transient as the exogenous ajmalicine was ultimately either metabolized in the medium or within the cell. the addition of neutral resin has previously been shown to enhance ajmalicine productio ...200212115404
trichosetin, a novel tetramic acid antibiotic produced in dual culture of trichoderma harzianum and catharanthus roseus callus.the dual culture of trichoderma harzianum and catharanthus roseus callus produced an antimicrobial compound with a remarkable activity against the gram-positive bacteria staphylococcus aureus and bacillus subtilis. structural elucidation revealed that this compound, which we have named trichosetin, is a novel tetramic acid (2,4-pyrrolidinedione) antibiotic and a homolog of the fungal metabolite equisetin. this compound however, was not produced in the individual culture of t. harzianum or c. ros ...200212132686
expression analysis in plant and cell suspensions of crckr1, a cdna encoding a histidine kinase receptor homologue in catharanthus roseus (l.) g. don.a full length cdna (crckr1) encoding a hybrid histidine kinase was isolated from a catharanthus roseus cdna library. the kinase belongs to the subfamily of cytokinin receptors represented by cre1/ahk4/wol in arabidopsis thaliana. in cell suspensions, the expression of crckr1 is not affected by various stress and hormonal treatments but is stimulated in cells continuously exposed to cytokinin. in plants, crckr1 is strongly expressed only in the petals of mature flowers. these data suggest that cr ...200212177139
current status of plant products reported to inhibit sperm.this report reviews research on plant-derived agents that prevent sperm production if taken orally by the male or that incapacitate or kill sperm on contact if used vaginally by the female. it would be of great value to develop fertility inhibitors that are totally selective for reproductive systems and enzymes, and there is a possibility that a plant-derived drug may have this effect. plants that have been studied for their fertility inhibiting effects in the male include: aristolochia indica l ...198212179631
lack of control in inorganic phosphate uptake by catharanthus roseus (l.) g. don cells (cytoplasmic inorganic phosphate homeostasis depends on the tonoplast inorganic phosphate transport system?).inorganic phosphate (pi) uptake by catharanthus roseus (l.) g. don cells was studied in relation to its apparent uncontrolled uptake using 31p-nuclear magnetic resonance spectroscopy. kinetics of pi uptake by the cells indicated that apparent km and vm were about 7 [mu]m and 20 [mu]mol g-1 fresh weight h-1, respectively. pi uptake in murashige-skoog medium under different pi concentrations and different initial cell densities followed basically the same kinetics. when supplied with abundant pi, ...199512228474
a cytochrome p-450 monooxygenase catalyzes the first step in the conversion of tabersonine to vindoline in catharanthus roseus.hydroxylation at the c-16 position of the indole alkaloid tabersonine has been suggested as the first step toward vindoline biosynthesis in catharanthus roseus. tabersonine 16-hydroxylase (16-oh) activity was detected in total protein extracts from young leaves of c. roseus using a novel coupled assay system. enzyme activity was dependent on nadph and molecular oxygen and was inhibited by co, clotrimazole, miconazole, and cytochrome c. 16-oh was localized to the endoplasmic reticulum by linear s ...199512228585
tryptophan decarboxylase, tryptamine, and reproduction of the whitefly.tryptophan decarboxylase (tdc) from catharanthus roseus (periwinkle) converts tryptophan to the indole-alkaloid tryptamine. when the tdc gene was expressed in transgenic tobacco, the 55-kd tdc enzyme and tryptamine accumulated. bemisia tabaci (sweetpotato whitefly) reproduction on transgenic plants decreased up to 97% relative to controls. production of tryptamine, its derivatives, or other products resulting from tdc activity may discourage whitefly reproduction and provide a single-gene-based ...199512228625
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
phosphatidate kinase, a novel enzyme in phospholipid metabolism (characterization of the enzyme from suspension-cultured catharanthus roseus cells).phosphatidate kinase (adenosine 5[prime]-triphosphate:phosphatidic acid phosphotransferase), a novel enzyme of phospholipid metabolism, was detected recently in the plasma membranes of suspension-cultured catharanthus roseus cells and purified (j.b. wissing, h. behrbohm [1993] plant physiol 102: 1243-1249). in the present work the properties of phosphatidate kinase are described. the enzyme showed a ph optimum of 6.1 and an isoelectric point of 4.8, and was rather stable in the presence of its s ...199412232252
supercritical fluid extraction and liquid chromatography-electrospray mass analysis of vinblastine from catharanthus roseus.supercritical fluid extraction using carbon dioxide modified with methanol, methanol-diethylamine, or methanol-triethylamine was used to extract vinblastine from the aerial portions of catharanthus roseus. an hplc-electrospray ionization (esi)/ms analysis method was also developed to quantify the alkaloids in these extracts. of the supercritical solvents evaluated, carbon dioxide-methanol-triethylamine (80 : 18 : 2) at 80 degrees c and 34.0 mpa greatly improved the supercritical fluid extraction ...200212237558
creation of a metabolic sink for tryptophan alters the phenylpropanoid pathway and the susceptibility of potato to phytophthora infestans.the creation of artificial metabolic sinks in plants by genetic engineering of key branch points may have serious consequences for the metabolic pathways being modified. the introduction into potato of a gene encoding tryptophan decarboxylase (tdc) isolated from catharanthus roseus drastically altered the balance of key substrate and product pools involved in the shikimate and phenylpropanoid pathways. transgenic potato tubers expressing the tdc gene accumulated tryptamine, the immediate decarbo ...199512242360
vindoline biosynthesis is transcriptionally blocked in catharanthus roseus cell suspension cultures.catharanthus roseus cell cultures were exposed to different conditions in order to induce alkaloid metabolism. the exposure to jasmonate and fungal elicitors resulted in the transcriptional activation of tryptophan decarboxylase and in the accumulation of the monoterpenoid indole alkaloids ajmalicine and catharanthine, but not of vindoline. the inability of the cell cultures to produce vindoline was related to a lack of expression of the desacetoxyvindoline 4-hydroxylase (d4h) gene. southern blo ...200212353909
continuous selective extraction of secondary metabolites from catharanthus roseus hairy roots with silicon oil in a two-liquid-phase bioreactor.a two-liquid-phase bioreactor was designed to extract indole alkaloids from catharanthus roseus hairy roots with silicon oil. partition studies between silicon oil and culture medium showed that the silicon oil did not alter the availability of nutrients. the affinity of tabersonine and löchnericine for silicon oil is nine times higher than for the aqueous phase. cultures were elicited with 25 mg/l of jasmonic acid. the growth of the hairy roots was not significantly modified by the presence of ...201512363351
an early c-22 oxidation branch in the brassinosteroid biosynthetic pathway.the natural occurrence of 22-hydroxylated steroids in cultured catharanthus roseus cells and in arabidopsis seedlings was investigated. using full-scan gas chromatography-mass spectrometry analysis, (22s)-22-hydroxycampesterol (22-ohcr), (22s,24r)-22-hydroxyergost-4-en-3-one (22-oh-4-en-3-one), (22s,24r)-22-hydroxy-5alpha-ergostan-3-one (22-oh-3-one), 6-deoxocathasterone (6-deoxoct), 3-epi-6-deoxoct, 28-nor-22-ohcr, 28-nor-22-oh-4-en-3-one, 28-nor-22-oh-3-one, 28-nor-6-deoxoct, and 3-epi-28-nor- ...200212376657
plant-cell bioreactors with simultaneous electropermeabilization and electrophoresis.experimental investigations on using low-level electric currents and voltages to extract, transport, and collect intracellular secondary metabolites from plant cells while maintaining their viabilities were conducted focusing on the production of: (1) ionic betalains, mainly negatively-charged betanin, from beta vulgaris cells, and (2) ionic alkaloids, particularly positively-charged ajmalicine and yohimbine, from catharanthus roseus cells. three versions of tubular membrane reactors in which el ...200312413782
transcription factors: tools to engineer the production of pharmacologically active plant metabolites.plants produce a variety of secondary metabolites, some of which are used as pharmaceuticals or are health promoting as food components. recent genetic studies on the flavonoid biosynthetic pathway show that transcription factors are efficient new molecular tools for plant metabolic engineering to increase the production of valuable compounds. the use of specific transcription factors would avoid the time-consuming step of acquiring knowledge about all enzymatic steps of a poorly characterized b ...200212457774
characterization of an inducible promoter system in catharanthus roseus hairy roots.transgenic hairy root cultures of catharanthus roseus were established with a glucocorticoid-inducible promoter controlling the expression of green fluorescent protein (gfp), and gfp expression was characterized. the inducible system shows a tightly controlled, reversible, and dosage-dependent response to the glucocorticoid dexamethasone in c. roseus hairy roots. full induction was noted after 12-18 h in the mature regions of the root tips and after 6 h in the meristem tissue. upon removal of th ...201312467449
a flavonol o-methyltransferase from catharanthus roseus performing two sequential methylations.protein extracts from dark-grown cell suspension cultures of catharanthus roseus (madagascar periwinkle) contained several o-methyltransferase (omt) activities, including the 16-hydroxytabersonine o-methyltransferase (16ht-omt) in indole alkaloid biosynthesis. this enzyme was enriched through several purification steps, including affinity chromatography on adenosine agarose. sds-page of the purified protein preparation revealed a protein band at the size expected for plant omts (38-43 kda). mass ...200312482447
biotransformation of 2alpha,5alpha,10beta,14beta-tetraacetoxy-4(20),11-taxadiene by cell suspension cultures of catharanthus roseus.catharanthus roseus cell suspension cultures were employed for the biotransformation of 2alpha,5alpha,10beta,14beta-tetraacetoxy-4(20),11-taxadiene ( 1), and four metabolites were obtained. based on their physical and chemical data, the structures of the four metabolites were respectively elucidated as 10beta-hydroxy-2alpha,5alpha,14beta-triacetoxy-4(20),11-taxadiene (2), 5alpha-hydroxy-2alpha,10beta, 14beta-triacetoxy-4(20),11-taxadiene (3), 6alpha,10beta-dihydroxy-2alpha,5alpha,14beta-triaceto ...200212494340
salt-tolerant mutants in glycophytic salinity response (gsr) genes in catharanthus roseus.the periwinkle catharanthus roseus shares glycophytic properties of crop plants. to contribute towards an understanding of the glycophytic response to salinity, large populations of m(2) seeds having an origin in nitroso-methyl urea and ethyl methane sulphonate treatments were screened for germination with 250 mm of nacl. out of the nine mutant lines so recovered, which tolerated salt stress due to loss of the normal glycophytic salinity response ( gsr), the characteristics of six gsr mutants ar ...200312582847
inhibition of the plant cytokinin transduction pathway by bacterial histidine kinase inhibitors in catharanthus roseus cell cultures.we describe the isolation of two catharanthus roseus cdnas encoding proteins putatively involved in the final steps of a 'histidine-to-aspartate' phosphorelay in cytokinin (ck) signaling. the expression of one of these genes, crrr1, was specifically up-regulated by cks in c. roseus cell suspensions. we used this system as a biological model to test the activity of bacterial histidine kinase inhibitors. our data demonstrate that these inhibitors are active on the ck transduction pathway and repre ...200312606039
immunocytolocalization of tryptophan decarboxylase in catharanthus roseus hairy roots.we investigated the intracellular distribution of tryptophan decarboxylase (tdc) (ec in catharanthus roseus hairy roots using immunofluorescence and immunogold techniques. tdc was detected by immunofluorescence localization in the cytosol and in the apoplastic region of the meristematic cells of the roots, with a slight enrichment in the epidermal cells of the root cap and in the meristematic region. in the enlargement zone, tdc was localized only in the first three layers of the corte ...200312611265
quantification of metabolic flux in plant secondary metabolism by a biogenetic organizational approach.metabolic engineering represents a promising approach to enhance the yield of valuable natural products from plants. a method to quantify flux through metabolite measurements is necessary for the analysis of native and modified pathways. rather than focusing only on the accumulation of the final products, analyzing a wide range of secondary metabolites has significant advantages. we propose a model that organizes the flux analysis by grouping metabolites of similar biosynthetic origin. to this e ...200212616695
phytotoxicity of the tetramic acid metabolite trichosetin.trichosetin, a tetramic acid-containing metabolite produced in the dual culture of trichoderma harzianum and catharanthus roseus (l.) g. don callus, was subjected to phytotoxicity assays. in seedling growth assays, trichosetin inhibited root and shoot growth of all five plant species tested by damaging the cell membrane, as evidenced by the dose-dependent increase in electrolyte leakage and lipid peroxidation. vital staining of trichosetin-treated nicotiana tabacum by-2 cells, with rhodamine 123 ...200312620323
production of anthocyanins by catharanthus roseus.a stable cell suspension line of catharanthus roseus producing anthocyanin was obtained. in this strain it was found that approximately 30% of cells regularly accumulated these metabolites and that anthocyanin accumulation occurred between the second half of log phase and the stationary phase of the culture growth cycle. the anthocyanins in the suspension cultures were compared with those biosynthetized in the flowers both of regenerated by somatic embryogenesis and field-grown plants. six antho ...200312628396
molecular characterization of recombinant t1, a non-allergenic periwinkle (catharanthus roseus) protein, with sequence similarity to the bet v 1 plant allergen family.more than 25% of the population suffer from type i allergy, an ige-mediated hypersensitivity disease. allergens with homology to the major birch ( betula verrucosa ) pollen allergen, bet v 1, belong to the most potent elicitors of ige-mediated allergies. t1, a cytokinin-inducible cytoplasmic periwinkle ( catharanthus roseus ) protein, with significant sequence similarity to members of the bet v 1 plant allergen family, was expressed in escherichia coli. recombinant t1 (rt1) did not react with ig ...200312656672
[neurological syndromes linked with the intake of plants and fungi containing a toxic component (i). neurotoxic syndromes caused by the ingestion of plants, seeds and fruits].a wide range of plants, seeds and fruits used for nutritional and medicinal purposes can give rise to neurotoxic symptoms.200312717675
screening of medicinal plants used in south african traditional medicine for genotoxic effects.dichloromethane and 90% methanol extracts from 51 south african medicinal plants were evaluated for potential genotoxic effects using the bacterial ames and vitotox tests with and without metabolic activation. dichloromethane extracts from bulbs of crinum macowanii showed mutagenicity in strain ta98 with and without metabolic activation, whereas extracts from leaves of chaetacme aristata and foliage of plumbago auriculata showed mutagenicity and/or toxicity. extracts from the leaves of catharant ...200312749823
studies on production of ajmalicine in shake flasks by multiple shoot cultures of catharanthus roseus.the effects of different concentrations of indole-3-acetic acid (iaa) and benzyladenine (ba) on production of ajmalicine by multiple shoot cultures of catharanthus roseus (c. roseus) were studied. by supplementing murashige and skoog's (ms) medium with a high concentration of iaa (11.42 microm) and a low concentration of ba (2.22 microm), shoot cultures accumulated high levels of ajmalicine. when culture medium was fortified with a low concentration of iaa (2.85 microm) and a high concentration ...201612790683
role of the non-mevalonate pathway in indole alkaloid production by catharanthus roseus hairy roots.the 1-deoxy-d-xylulose-5-phosphate (dxp) pathway (non-mevalonate pathway) leading to terpenoids via isopentenyl diphosphate (ipp) has been shown to occur in most bacteria and in all higher plants. treatment with the antibiotic fosmidomycin, a specific inhibitor of dxp reductoisomerase, considerably inhibited the accumulation of the alkaloids ajmalicine, tabersonine, and lochnericine by catharanthus roseus hairy root cultures in the exponential growth phase. however, fosmidomycin did not signific ...201312790690
natural products of plant origin as anticancer agents.natural products have been used as effective remedies for the treatment of various ailments. numerous plant products in the form of decoction, tincture, tablets and capsules have been clinically used for the treatment of different kinds of cancer. this review covers some of the important plants with clinically proven anticancer activity, including catharanthus roseus, podophyllum peltatum, taxus brevifolia, camptothecin acuminata, cephalotaxus harringtonia, viscum album, onchrosia elliptica, ann ...200112806432
differential expression of two type-a response regulators in plants and cell cultures of catharanthus roseus (l.) g. don.two full-length cdnas named crrr2 and crrr3 have been isolated by pcr from a c. roseus cdna library. the first one encodes a 154 amino acid putative protein with a high percentage of identity with the arabidopsis thaliana response regulators arr16 and arr17, and is not expressed in c. roseus organs and cell cultures. the second one encodes a 188 amino acid orf sharing the highest homologies with the a. thaliana arr8 and arr9 response regulators. its expression is root-specific and the transcript ...200312810857
jasmonate-induced epoxidation of tabersonine by a cytochrome p-450 in hairy root cultures of catharanthus roseus.methyl jasmonate, a chemical inducer of secondary metabolism, was shown to promote tabersonine 2 biosynthesis in hairy root cultures of catharanthus roseus. tabersonine 6,7-epoxidase activity was detected in total protein extract of jasmonate-induced hairy root cultures using labeled 14c-tabersonine 2. this enzyme converted tabersonine 2 to lochnericine 3 by selective epoxidation at positions 6 and 7 via a reaction dependent on nadph and molecular oxygen. carbon monoxide, clotrimazole, miconazol ...200312943756
the juice of fresh leaves of catharanthus roseus linn. reduces blood glucose in normal and alloxan diabetic rabbits.the leaf juice or water decoction of catharanthus roseus l. (apocyanaceae) is used as a folk medicine for the treatment of diabetes all over the world. in the present investigation, the leaf juice of c. roseus has been evaluated for its hypoglycemic activity in normal and alloxan-induced diabetic rabbits.200312950994
crmyc1, a catharanthus roseus elicitor- and jasmonate-responsive bhlh transcription factor that binds the g-box element of the strictosidine synthase gene promoter.a cdna encoding a bhlh transcription factor was isolated by the yeast one-hybrid system from a catharanthus roseus cdna library using the g-box element of the strictosidine synthase gene promoter as bait. the corresponding protein (named crmyc1) was shown to bind specifically to the g-box in yeast. in c. roseus suspension cells crmyc1 mrna levels are induced by fungal elicitor and jasmonate suggesting that crmyc1 may be involved in the regulation of gene expression in response to these signals.200312966042
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a note on the alkaloids of vinca rosea linn. (catharanthus roseus g. don.). ii. catharanthine, lochnericine, vindolinine, and vindoline. 195913641069
alkaloids of vinca rosea linn. (catharanthus roseus g. don.). v. preparation and characterization of alkaloids. 195913854990
alkaloids of vinca rosea linn. (catharanthus roseus g. don.) xii. preparation and characterization of trace alkaloids. 196213918739
current status of research on the alkaloids of vinca rosea linn. (catharanthus roseus g. don). 196213918740
alkaloids of vinca rosea linn. (catharanthus roseus g. don). xv. analysis of vinca alkaloids by thin-layer chromatography. 196314022560
[therapeutic action of the alkaloids of catharanthus roseus (vinca rosea) on hodgkin's disease and acute leukosis]. 201314190930
alkaloids of vinca rosea linn. (catharanthus roseus g. don). xxiv. vinaspine, vincathicine, rovidine, desacetyl vlb, and vinaphamine. 196414249445
effect of colchicine and catharanthus roseus (vinca rosea) alkaloids on mitosis of syrian hamster bone marrow cells. 196514300954
[on alkaloid formation in tissue culture by catharanthus roseus g. don]. 196514331116
peroxidase from catharanthus roseus (l.) g. don and the biosynthesis of alpha-3',4'-anhydrovinblastine: a specific role for a multifunctional enzyme.we have characterized a basic peroxidase with alpha-3',4'-anhydrovinblastine (avlb) synthase activity, which was purified from catharanthus roseus leaves. this enzyme was the single peroxidase isoenzyme detected in c. roseus leaves, and the single avlb synthase activity detected in c. roseus extracts. it was observed that the monomeric substrates of avlb, vindoline and catharanthine, are both suitable electron donors for the oxidizing intermediates of the basic peroxidase, compounds i and ii. re ...200314513315
increase in the indole alkaloid production and its excretion into the culture medium by calcium antagonists in catharanthus roseus hairy roots.treatment of catharanthus roseus hairy roots with antagonists, like verapamil and cdcl2, that block the ca2+ flux across the plasma membrane enhanced the total alkaloid content by 25% and their secretion 10 times. the specific ca2+ chelator, egta, stimulated 90% of the total alkaloid secretion. treatment with inhibitors of intracellular ca2- movement, like tmb-8 and trapsigargin, enhanced the total alkaloid content by 74% and their secretion into the culture media by 4- to 6-fold. the results su ...200314514063
production of cell wall accumulative enzymes using immobilized protoplasts of catharanthus roseus in agarose gel.catharanthus roseus cells and protoplasts were used for production of peroxidase and alpha-galactosidase which are accumulated in the cell wall. only 4% (0.026 u ml(-1)) of the total peroxidase was secreted into the broth by cultured cells while in cultured protoplasts, 45% (0.12 u ml(-1)) was secreted. protoplasts were protected against the physical and osmotic stresses by immobilizing them in 3% agarose gel (high mass transfer, non-electric charge, low gelation temperature). in order to increa ...200314626409
production of unnatural glucosides of curcumin with drastically enhanced water solubility by cell suspension cultures of catharanthus roseus.catharanthus roseus cell suspension cultures converted exogenously supplied curcumin to a series of glucosides, none of which has been found in nature so far. the efficiency of glucosylation was dependent on culture stage of the cells and medium sucrose concentration. methyl jasmonate and salicylic acid enhanced the glucoside formation only when they were added to the cultures prior to the addition of curcumin. the glucoside yield was 2.5 micromol/g fresh weight of the cells at an optimal cultur ...200314644434
cytochemical localization of calcium and x-ray microanalysis of catharanthus roseus l. infected with phytoplasmas.the potassium pyroantimonate (kpa) ca(2+) precipitation technique, x-ray microanalysis and electron energy loss spectroscopy carried out by transmission electron microscopy were used to analyze the ca(2+) distribution in catharanthus roseus l. leaves infected with phytoplasmas belonging to different taxonomic groups, and in phytoplasma cells. the analysis revealed that the distribution of ca(2+) was different in healthy and diseased plants (where the kpa deposits were numerous) and no difference ...200314680925
histidine-containing phosphotransfer domain extinction by rna interference turns off a cytokinin signalling circuitry in catharanthus roseus suspension cells.we previously reported that cytokinins (ck) induce the fast and specific transcription of crrr1, a gene encoding a type a response regulator in catharanthus roseus cell cultures. here, we characterized the crhpt1 gene that encodes a histidine-containing phosphotransfer domain. crhpt1 was silenced through rna interference (rnai) to test its possible implication in the ck signalling pathway. in transgenic lines stably transformed with an intron-spliced construct, the degradation of crhpt1 transcri ...200414759521
plant regeneration from hairy-root cultures transformed by infection with agrobacterium rhizogenes in catharanthus roseus.hypocotyl explants of catharanthus roseus produced hairy roots when cultured on murashige and skoog (ms) basal medium after infection by agrobacterium rhizogenes. explants gave rise to adventitious shoots at a frequency of up to 80% when cultured on ms medium supplemented with 31.1 microm 6-benzyladenine and 5.4 microm alpha-naphthaleneacetic acid. there was a significant difference in the frequency of adventitious shoot formation for each hairy-root line derived from a different cultivar. plant ...200414963692
catharanthus roseus l. plants and explants infected with phytoplasmas: alkaloid production and structural observations.the results of several experiments concerning the presence and composition of alkaloids in different tissues (stems, leaves, roots) of catharanthus roseus l. plants and explants, healthy and infected by clover phyllody phytoplasmas, are reported. the alkaloids extracted and determined by the reverse phase high-pressure liquid chromatography were vindoline, ajmalicine, serpentine, vinblastine, and vincristine. the total alkaloid concentration was higher in infected plants than in the controls, in ...200415004742
biotransformation of triptolide and triptonide by cell suspension cultures of catharanthus roseus.catharanthus roseus cell suspension cultures were used to bioconvert both triptolide (1) and triptonide (2). the same reaction path was followed in both biotransformations. two biotransformed products were obtained and their structures identified as triptriolide (3) and 12beta,13alpha-dihydroxytriptonide (4), respectively, from 1 and 2. product 4 is a new compound.200415008455
angiogenesis and anti-angiogenesis activity of chinese medicinal herbal extracts.the aqueous extracts of 24 herbs traditionally used as curing ischemic heart disease in clinic in china were screened for their in vitro angiogenic activity, another twenty-four traditionally used as anti-tumor or anti-inflammatory remedies in china were screened for their in vitro anti-angiogenic activity. the activity of angiogenesis was determined by quantitation of vessels on chick embryo chorioallantoic membrane (cam) model and cell proliferation of cultured bovine aortic endothelial cells ...200415010258
the catharanthus alkaloids: pharmacognosy and biotechnology.the catharanthus (or vinca) alkaloids comprise a group of about 130 terpenoid indole alkaloids. vinblastine is now marketed for more than 40 years as an anticancer drug and became a true lead compound for drug development. due to the pharmaceutical importance and the low content in the plant of vinblastine and the related alkaloid vincristine, catharanthus roseus became one of the best-studied medicinal plants. consequently it developed as a model system for biotechnological studies on plant sec ...200415032608
interaction of spermine with a signal transduction pathway involving phospholipase c, during the growth of catharanthus roseus transformed cantharanthus roseus transformed roots, the application of methylglyoxal bis(guanylhydrazone) (mgbg), an inhibitor of s-adenosylmethionine decarboxylase (samdc; ec, inhibited the root growth in a dose-dependent manner with a dl(50) of about 300 micro m. spermidine and spermine (spm) levels and samdc and phospholipase c (plc; ec activities were reduced in the presence of the inhibitor. the inhibition was reversed by the addition of spm. radioactivity from [(14)c]spm was dete ...200415032886
co-expression of three mep pathway genes and geraniol 10-hydroxylase in internal phloem parenchyma of catharanthus roseus implicates multicellular translocation of intermediates during the biosynthesis of monoterpene indole alkaloids and isoprenoid-derived primary higher plants, isopentenyl diphosphate (ipp) is synthesised both from the plastidic 2-c-methyl-d-erythritol 4-phosphate (mep) and from the cytosolic mevalonate (mva) pathways. primary metabolites, such as phytol group of chlorophylls, carotenoids and the plant hormones abscisic acid (aba) and gibberellins (gas) are derived directly from the mep pathway. many secondary metabolites, such as monoterpene indole alkaloids (mias) in catharanthus roseus, are also synthesised from this source of ipp. ...200415053766
map kinase-like activity in transformed catharanthus roseus hairy roots varies with culture conditions such as temperature and hypo-osmotic shock.mitogen activated protein (map) kinase-like activity was determined in extracts obtained from transformed catharanthus roseus hairy roots by the ability to phosphorylate myelin basic protein (mbp). both in solution and in gel kinase assays showed variation in activity, depending on root developmental stage. in gel kinase assays, using the extract soluble fraction, revealed a 56 kda polypeptide with phosphorylation activity on mbp. in addition, another 75 kda polypeptide was observed in the parti ...200415061086
flavonoid methylation: a novel 4'-o-methyltransferase from catharanthus roseus, and evidence that partially methylated flavanones are substrates of four different flavonoid dioxygenases.catharanthus roseus (madagascar periwinkle) flavonoids have a simple methylation pattern. characteristic are b-ring 5' and 3' methylations and a methylation in the position 7 of the a-ring. the first two can be explained by a previously identified unusual o-methyltransferase (cromt2) that performs two sequential methylations. we used a homology based rt-pcr strategy to search for cdnas encoding the enzyme for the a-ring 7 position. full-length cdnas for three proteins were characterized (cromt5, ...200415110688
expression of a feedback-resistant anthranilate synthase in catharanthus roseus hairy roots provides evidence for tight regulation of terpenoid indole alkaloid levels.different plant species produce a variety of terpenoid indole alkaloids, which are of interest as plant defensive secondary metabolites and as valuable pharmaceuticals. although significant progress has been made, the mechanisms regulating the levels of this important class of compounds require continued elucidation. previous precursor feeding studies have indicated that alkaloid accumulation can be improved during the exponential growth phase of hairy root cultures through enhanced tryptophan a ...200415137084
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