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predicting leaf-level fluxes of o3 and no2: the relative roles of diffusion and biochemical processes.pollutants like o(3) and no(2) enter leaves through the stomata and cause damage during reactions with components of biological cell membranes. the steady-state flux rates of these gases into the leaf are determined by a series of physical and biochemical resistances including stomatal aperture, reactions occurring within the cell wall and the ability of the leaf to remove the products of apoplastic reactions. in the present study, multiple regression models incorporating stomatal conductance, a ...200616913863
expressed sequence tags from madagascar periwinkle (catharanthus roseus).the madagascar periwinkle (catharanthus roseus) is well known to produce the chemotherapeutic anticancer agents, vinblastine and vincristine. in spite of its importance, no expressed sequence tag (est) analysis of this plant has been reported. two cdna libraries were generated from rna isolated from the base part of young leaves and from root tips to select 9,824 random clones for unidirectional sequencing, to yield 3,327 related sequences and 1,696 singletons by cluster analysis. putative funct ...200616870181
identification of a low vindoline accumulating cultivar of catharanthus roseus (l.) g. don by alkaloid and enzymatic profiling.the madagascar periwinkle [catharanthus roseus (l.) g. don] is a commercially important horticultural flower species and is the only source of the monoterpenoid indole alkaloids (mias), vinblastine and vincristine, key pharmaceutical compounds used to combat a number of different cancers. the present study uses high performance liquid chromatography for metabolic profiling of the mias extracted from seedlings and young leaves of 50 different flowering cultivars of c. roseus to show that, except ...200616806326
catharanthus roseus shoot cultures for the production of monoterpenoid indole alkaloids.a protocol for the establishment of in vitro shoot cultures of catharanthus roseus is described. shoots can be maintained for more than 1 yr without evidence of tissue vitrification, disaggregation, or callus formation. vindoline was the main alkaloid accumulated, reaching values similar to those found in leaves from field-grown plants, after a long period of culture. an induction methodology to reduce such waiting time is also presented.200616673929
methylation of sulfhydryl groups: a new function for a family of small molecule plant o-methyltransferases.in plants, type i and ii s-adenosyl-l-methionine-dependent o-methyltransferases (omts) catalyze most hydroxyl group methylations of small molecules. a homology-based rt-pcr strategy using catharanthus roseus (madagascar periwinkle) rna previously identified six new type i plant omt family members. we now describe the molecular and biochemical characterization of a seventh protein. it shares 56-58% identity with caffeic acid omts (comts), but it failed to methylate comt substrates, and had no act ...200616623883
gene-to-metabolite networks for terpenoid indole alkaloid biosynthesis in catharanthus roseus cells.rational engineering of complicated metabolic networks involved in the production of biologically active plant compounds has been greatly impeded by our poor understanding of the regulatory and metabolic pathways underlying the biosynthesis of these compounds. whereas comprehensive genome-wide functional genomics approaches can be successfully applied to analyze a select number of model plants, these holistic approaches are not yet available for the study of nonmodel plants that include most, if ...200616565214
micropropagation: a tool for the production of high quality plant-based medicines.medicinal plants are the most important source of life saving drugs for the majority of the world's population. the biotechnological tools are important to select, multiply and conserve the critical genotypes of medicinal plants. plant tissue culture techniques offer an integrated approach for the production of standardized quality phytopharmaceutical through mass-production of consistent plant material for physiological characterization and analysis of active ingredients. micropropagation proto ...200616472132
precursor limitations in methyl jasmonate-induced catharanthus roseus cell cultures.jasmonates enhance the expression of various genes involved in terpenoid indole alkaloid (tia) biosynthesis in catharanthus roseus. we applied precursor feeding to our c. roseus suspensions to determine how methyl jasmonate (mj) alters the precursor availability for tia biosynthesis. c. roseus suspensions were induced with mj (100 microm) on day 6 and fed loganin (0.30 mm), tryptamine (0.15 mm), loganin plus tryptamine, or geraniol (0.1-1.0 mm) on day 7. while mj increased ajmalicine production ...200616432630
rapid identification of vinca alkaloids by direct-injection electrospray ionisation tandem mass spectrometry and confirmation by high-performance liquid chromatography-mass spectrometry.a simple and rapid method for the identification of vinca alkaloids from a crude extract of catharanthus roseus g. don (apocynaceae) by direct-injection electrospray ionisation (esi) and tandem mass spectrometry (ms/ms) has been developed. the alkaloids vindoline, vindolidine, vincristine and vinblastine were evaluated in a commercial extract of c. roseus using this method. catharanthine and its isomers 19s-vindolinine and vindolinine were detected in the commercial product by direct injection e ...200616223089
effects of terpenoid precursor feeding on catharanthus roseus hairy roots over-expressing the alpha or the alpha and beta subunits of anthranilate synthase.among the pharmacologically important terpenoid indole alkaloids produced by catharanthus roseus are the anti-cancer drugs vinblastine and vincristine. these two drugs are produced in small yields within the plant, which makes them expensive to produce commercially. metabolic engineering has focused on increasing flux through this pathway by various means such as elicitation, precursor feeding, and introduction of genes encoding specific metabolic enzymes into the plant. recently in our lab, a f ...200616240438
transient effects of overexpressing anthranilate synthase alpha and beta subunits in catharanthus roseus hairy roots.catharanthus roseus produces two economically valuable anticancer drugs, vinblastine and vincristine. these drugs are members of the terpenoid indole alkaloids and accumulate in small quantities within the plant; thus these two drugs are expensive to produce. metabolic engineering efforts have focused on increasing the alkaloids in this pathway through various means such as elicitation, precursor feeding, and gene overexpression. recently we successfully expressed arabidopsis genes encoding a fe ...200616209565
expression of the arabidopsis feedback-insensitive anthranilate synthase holoenzyme and tryptophan decarboxylase genes in catharanthus roseus hairy roots.in plants, the indole pathway provides precursors for a variety of secondary metabolites. in catharanthus roseus, a decarboxylated derivative of tryptophan, tryptamine, is a building block for the biosynthesis of terpenoid indole alkaloids. previously, we manipulated the indole pathway by introducing an arabidopsis feedback-insensitive anthranilate synthase (as) alpha subunit (trp5) cdna and c. roseus tryptophan decarboxylase gene (tdc) under the control of a glucocorticoid-inducible promoter in ...200616188339
[role of elements and physiologically active compounds in the regulation of synthesis and accumulation of indole alkaloids in catharanthus roseus l].effects of various elements (co, ni, zn, w, mn, cr, b, mo, fe, and v), natural and synthetic auxins, cytokinins, and gibberellin on biosynthesis and accumulation of indole alkaloids was studied at increasing concentrations in the model system of madagascar periwinkle seedlings (catharanthus roseus l.). the main types of concentration dependences for the effect of physiologically active compounds under study were evaluated. a possible mechanism of the influence of zn and auxin on this process was ...200615977796
allelic differences at two loci govern different mechanisms of intraflower self-pollination in self-pollinating strains of periwinkle.periwinkle [catharanthus roseus (l.) g. don], an ornamental and medicinal plant, is a self-compatible, insect-pollinated plant species in which intraflower self-pollination does not occur because of spatial separation of the stigma and anthers. recently three self-pollinating strains-mj, vi, and or-were identified. self-pollination in these strains was found to be brought about by continuous increase in gynoecium length from anthesis to self-pollination, in contrast to non-self-pollinating strai ...200615598715
symmetry c18 column: a better choice for the analysis of indole alkaloids of catharanthus roseus.by 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
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
methyljasmonate accelerates catabolism of monoterpenoid indole alkaloids in catharanthus roseus during leaf processing.variations in alkaloid pattern during drying of leaves (leaf processing) showed that treatment with methyljasmonate can induce formation of bisindole alkaloids as a result of catabolism of the monomeric alkaloids catharanthine and vindoline. a two-fold increase in 3',4'-anhydrovinblastine was shown in treated leaves especially from day 8 until day 21. serpentine also increased in the same period under the treatment as a catabolic product of ajmalicine. basic peroxidases that are responsible for ...200515664467
effect of nitric oxide on catharanthine production and growth of catharanthus roseus suspension cells.sodium nitroprusside (snp) was used as the donor of nitric oxide (no) to investigate its effect on catharanthine synthesis and the growth of catharanthus roseus suspension cells. the results showed that snp at high concentrations (10.0 and 20.0 mmol/l) stimulated catharanthine formation of c. roseus cells, but inhibited growth of the cells. low concentrations of snp (0.1 and 0.5 mmol/l) enhanced the growth of c. roseus cells, but had no effect on catharanthine synthesis. the maximum total cathar ...200515744842
purification, molecular cloning, and cell-specific gene expression of the alkaloid-accumulation associated protein crps in catharanthus roseus.identification of molecular markers of monoterpenoid indole alkaloid (mia) accumulation in cell-suspension cultures of madagascar periwinkle (catharanthus roseus (l.) g. don) was performed by two-dimensional polyacrylamide gel electrophoresis. comparison of the protein patterns from alkaloid-producing and non-producing cells showed the specific occurrence of a 28 kda polypeptide restricted to cells accumulating mias. the polypeptide was purified by preparative two-dimensional gel electrophoresis ...200515737982
expression of terpenoid indole alkaloid biosynthetic pathway genes corresponds to accumulation of related alkaloids in catharanthus roseus (l.) g. don.madagascar periwinkle, catharanthus roseus (l.) g. don, a medicinally important plant, produces anticancer dimeric alkaloids, vinblastine and vincristine, in the leaves and accumulates antihypertensive alkaloids, ajmalicine and serpentine, in the roots. this plant grows wild in distant tropical and sub-tropical geographical locations with different agro-climates and shows wide variations in morphological and alkaloid yield-related traits. in order to understand the correlation between the expres ...200515714355
proteome analysis of the medicinal plant catharanthus roseus.a proteomic approach is undertaken aiming at the identification of novel proteins involved in the alkaloid biosynthesis of catharanthus roseus. the c. roseus cell suspension culture a11 accumulates the terpenoid indole alkaloids strictosidine, ajmalicine and vindolinine. cells were grown for 21 days, and alkaloid accumulation was monitored during this period. after a rapid increase between day 3 and day 6, the alkaloid content reached a maximum on day 16. systematic analysis of the proteome was ...200515682277
cytokinin and ethylene control indole alkaloid production at the level of the mep/terpenoid pathway in catharanthus roseus suspension cells.the madagascar periwinkle catharanthus roseus accumulates a number of terpenoid indole alkaloids, some of which have high therapeutic interest. the biotechnological approach with cells in vitro remains an alternative to the field culture of periwinkle for the production of such compounds. we previously reported that two phytohormones, cytokinin and ethylene, remarkably enhanced the accumulation of alkaloids in periwinkle cell suspensions. in this work, we investigated the effects of these hormon ...200515971133
phytic acid synthesis and vacuolar accumulation in suspension-cultured cells of catharanthus roseus induced by high concentration of inorganic phosphate and cations.we have established a new system for studying phytic acid, myo-inositol hexakisphosphate (insp(6)) synthesis in suspension-cultured cells of catharanthus. insp(6) and other intermediates of myo-inositol (ins) phosphate metabolism were measured using an ion chromatography method. the detection limit for insp(6) was less than 50 nm, which was sufficient to analyze ins phosphates in living cells. synthesis of ins phosphates was induced by incubation in high inorganic phosphate medium. insp(6) was m ...200515965017
caax-prenyltransferases are essential for expression of genes involvedin the early stages of monoterpenoid biosynthetic pathway in catharanthus roseus cells.caax-prenyltransferases (caax-ptases) catalyse the covalent attachment of isoprenyl groups to conserved cysteine residues located at the c-terminal caax motif of a protein substrate. this post-translational modification is required for the function and/or subcellular localization of some transcription factors and components of signal transduction and membrane trafficking machinery. caax-ptases, including protein farnesyltransferase (pft) and type-i protein geranylgeranyltransferase (pggt-i), are ...200515952070
cytochrome p450 2d6 (cyp2d6) inhibitory constituents of catharanthus roseus.the meoh-soluble fraction of the water extract of catharanthus roseus from indonesia, having shown potent inhibitory activity on the metabolism mediated by cyp2d6, was subjected to activity-guided isolation to yield two triterpenes, ursolic acid (1) and oleanolic acid (2), and three alkaloids, vindoline (3), ajmalicine (4), and serpentine (5). the isolated compounds were tested for their inhibitory activity on the metabolism mediated by cyp3a4 or cyp2d6 using [n-methyl-14c]erythromycin or [o-met ...200515930738
ajmalicine production in methyl jasmonate-induced catharanthus roseus cell cultures depends on ca2+ level.cytosolic ca(2+) and jasmonate mediate signals that induce defense responses in plants. in this study, the interaction between ca(2+) and methyl jasmonate (mj) in modulating defense responses was investigated by monitoring ajmalicine production in catharanthus roseus suspension cultures. c. roseus suspensions were treated with nine combinations of cacl(2) (3, 23, and 43 mm) and mj (0, 10, and 100 microm) on day 6 of growth. increased ca(2+) influx through the addition of extracellular cacl(2) su ...200516094527
biotransformation of alpha-santonin by cell suspension cultures of five plants.cell suspension cultures of five plants (catharanthus roseus, ginkgo biloba, platycodon grandiflorum, taxus cuspidata, phytolacca asinosa) were employed to bioconvert the eudesmanolide compound, alpha-santonin. reactions occurring were hydroxylation (c-1, c-11 and c-15), reduction of the double bond [1(2) or 3(4)], rearrangment of the eudesmanolide skeleton to a guaianolide skeleton and lactone-ring hydrolysis. four new compounds were identified.200516086262
fosmidomycin analogues as inhibitors of monoterpenoid indole alkaloid production in catharanthus roseus cells.substituted 3-[2-(diethoxyphosphoryl)propyl]oxazolo[4,5-b]pyridine-2(3h)-ones were obtained by functionalization at 6-position with various substituents (aryl, vinyl, carbonyl chains) via reactions catalysed with palladium. we found that these new fosmidomycin analogues inhibited the accumulation of ajmalicine, a marker of monoterpenoid indole alkaloids production in plant cells. some of them have greater inhibitory effect than fosmidomycin and fully inhibit alkaloid accumulation at the concentr ...200516054176
processing methods for differential analysis of lc/ms profile data.liquid chromatography coupled to mass spectrometry (lc/ms) has been widely used in proteomics and metabolomics research. in this context, the technology has been increasingly used for differential profiling, i.e. broad screening of biomolecular components across multiple samples in order to elucidate the observed phenotypes and discover biomarkers. one of the major challenges in this domain remains development of better solutions for processing of lc/ms data.200516026613
development of a novel system for producing ajmalicine and serpentine using direct culture of leaves in catharanthus roseus intact plant.due to problems of production instability, the production of plant secondary metabolites using dedifferentiated cells (callus) is not always feasible on an industrial scale. to propose a new methodology, which does not use dedifferentiated cells, a novel system for producing useful secondary metabolites using the direct culture of intact plant leaves was developed. catharanthus roseus was used as a model medicinal plant to produce terpenoid indole alkaloids (tias) by suspension culture of the le ...200516233779
simultaneous determination of vincristine, vinblastine, catharanthine, and vindoline in leaves of catharanthus roseus by high-performance liquid chromatography.a simple reversed-phase liquid chromatographic method is developed for the simultaneous quantitation of the anticancerous drugs vincristine, vinblastine, and their precursors catharanthine and vindoline using a merck chromolith performance reversed-phase high-performance liquid chromatography column. a better resolution is obtained in comparison with available particulate-type c18 columns. the column provides good reproducibility and peak symmetry. chromatography is carried isocratically with a ...200516212789
isolation of a cdna encoding the alpha-subunit of caax-prenyltransferases from catharanthus roseus and the expression of the active recombinant protein farnesyltransferase.crfta/ggt_ia (af525030), a cdna encoding the ?-subunit of the two types of caax-prenyltransferase (caax-ptase), i.e. protein farnesyltransferase (pft) and type i protein geranylgeranyltransferase, was cloned from catharanthus roseus via a pcr strategy. crfta/ggt_ia is 1381-bp long and bears a 999-bp open reading frame encoding a protein of 332 residues (fta) that shares 66% identity with its lycopersicon esculentum orthologue. southern blot analysis revealed that fta is encoded by a single gene ...200516341273
localization of tabersonine 16-hydroxylase and 16-oh tabersonine-16-o-methyltransferase to leaf epidermal cells defines them as a major site of precursor biosynthesis in the vindoline pathway in catharanthus roseus.the madagascar periwinkle (catharanthus roseus) produces the well known and remarkably complex anticancer dimeric alkaloids vinblastine and vincristine, which are derived by the coupling of vindoline and catharanthine monomers. recent data from in situ rna hybridization and immunolocalization suggest that combinatorial cell factories within the leaf are involved in vindoline biosynthesis. in this study, the cell types responsible for vindoline biosynthesis were identified by laser-capture microd ...200516262708
sugar import and phytopathogenicity of spiroplasma citri: glucose and fructose play distinct roles.we have shown previously that the glucose pts (phosphotransferase system) permease enzyme ii of spiroplasma citri is split into two distinct polypeptides, which are encoded by two separate genes, crr and ptsg. a s. citri mutant was obtained by disruption of ptsg through homologous recombination and was proved unable to import glucose. the ptsg mutant (gii3-glc1) was transmitted to periwinkle (catharanthus roseus) plants through injection to the leaf-hopper vector. in contrast to the previously c ...200515672816
combinatorial natural products: from cloning to analysis.medicinal compounds from plants represent one of the largest and most diverse groups of plant secondary metabolites. the advent of advanced bioinformatics tools and modern genetic technology allowed for manipulation of biosynthetic pathways with the potential of generating novel chemical entities. first, public databases of secondary metabolite related enzymes were interrogated to identify relevant plant genes from vinca rosea (catharanthus roseus) and other species. genes of interest were teste ...200515790307
characterization of a polyclonal antiserum against the monoterpene monooxygenase, geraniol 10-hydroxylase from catharanthus roseus.geraniol 10-hydroxylase (g10h) is a p450 containing enzyme which is the first committed step in the biosynthesis of monoterpene indole alkaloids (mias), including the catharanthus roseus-anticancer drugs vinblastine and vincristine. it is thought that g10h has a regulatory role in mia production. in the present paper, we report the characterization of a polyclonal serum raised against the purified g10h polypeptide. anti-g10h igg was able to inhibit the g10h activity and also recognized the g10h ...200515900881
[a study on the hairy root culture and antitumor alkaloids production of catharanthus roseus].to establish transformation system and obtain alkaloids from the hairy root of catharanthus roseus.200516075710
elicitor-induced nitric oxide burst is essential for triggering catharanthine synthesis in catharanthus roseus suspension cells.elicitor prepared from the cell walls of penicillium citrinum induced multiple responses in catharanthus roseus suspension cells, including rapid generation of nitric oxide (no), sequentially followed by enhancement of catharanthine production by c. roseus cells. elicitor-induced catharanthine biosynthesis was blocked by no-specific scavenger 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and nitric oxide synthase (nos) inhibitor s,s'-1,3-phenylene-bis(1,2-ethanediyl)-bis-isothi ...200515480633
distribution of phytoplasmas in infected plants as revealed by real-time pcr and bioimaging.phytoplasmas are cell wall-less bacteria inhabiting the phloem and utilizing it for their spread. infected plants often show changes in growth pattern and a reduced crop yield. a quantitative real-time polymerase chain reaction (q-pcr) assay and a bioimaging method were developed to quantify and localize phytoplasmas in situ. according to the q-pcr assay, phytoplasmas accumulated disproportionately in source leaves of euphorbia pulcherrima and, to a lesser extent, in petioles of source leaves an ...200415553243
activation of the oxidative burst by yeast elicitor in catharanthus roseus cells occurs independently of the activation of genes involved in alkaloid biosynthesis.in catharanthus roseus cell suspensions, expression of several terpenoid indole alkaloid (tia) biosynthetic genes, including those encoding strictosidine synthase and tryptophan decarboxylase, is coordinately induced by fungal elicitors such as yeast extract (ye). this induction is mediated by several signaling steps including the biosynthesis of jasmonic acid, and the activation of the jasmonic acid-responsive orca transcription factors. we investigated a possible role of reactive oxygen specie ...200415604717
synthesis and biological evaluation with plant cells of new fosmidomycin analogues containing a benzoxazolone or oxazolopyridinone ring.fosmidomycin, 3-(n-formyl-n-hydroxyamido) propylphosphonic acid sodium salt, is an efficient inhibitor of 1-deoxy-d-xylulose-5-phosphate (doxp) reductoisomerase, the second enzyme of the 2c-methyl-d-erythritol-4-phosphate (mep) pathway notably present in plasmodium species. we have synthesized a new series of analogues of fosmidomycin, containing a benzoxazolone, benzoxazolethione or oxazolopyridinone ring. as the mep pathway is involved in the biosynthesis of all isoprenoids, accumulation of aj ...200415662959
molecular cloning and characterization of a glucosyltransferase catalyzing glucosylation of curcumin in cultured catharanthus roseus cells.catharanthus roseus cell suspension cultures are capable of converting exogenously supplied curcumin to various glucosides. the glucosylation efficiency is enhanced by addition of methyl jasmonate (mj) to the cultures prior to curcumin administration. two cdnas encoding udp-glucosyltransferases (caugt1 and caugt2) were isolated from a cdna library of cultured c. roseus cells, using a pcr method directed at the conserved udp-binding domain of plant glycosyltransferases. the sequence identity betw ...200415178322
growth and terpenoid indole alkaloid production in catharanthus roseus hairy root clones in relation to left- and right-termini-linked ri t-dna gene integration.hairy root cultures of catharanthus roseus var. prabal were established by infecting the leaves with agrobacterium rhizogenes agropine-type a4 strain. two hundred and fifty independent root clones were evaluated for growth, morphology, number of integration of ri t-dna genes and alkaloid contents. on the basis of growth pattern, type of branching and number of lateral roots we were able to separate the hairy root clones into four categories. however based on the integration of the ri t(l)-dna an ...200415221274
metabolic discrimination of catharanthus roseus leaves infected by phytoplasma using 1h-nmr spectroscopy and multivariate data analysis.a comprehensive metabolomic profiling of catharanthus roseus l. g. don infected by 10 types of phytoplasmas was carried out using one-dimensional and two-dimensional nmr spectroscopy followed by principal component analysis (pca), an unsupervised clustering method requiring no knowledge of the data set and used to reduce the dimensionality of multivariate data while preserving most of the variance within it. with a combination of these techniques, we were able to identify those metabolites that ...200415286294
zinc finger proteins act as transcriptional repressors of alkaloid biosynthesis genes in catharanthus roseus.in catharanthus roseus cell suspensions, the expression of several terpenoid indole alkaloid biosynthetic genes, including two genes encoding strictosidine synthase (str) and tryptophan decarboxylase (tdc), is coordinately induced by fungal elicitors such as yeast extract. to identify molecular mechanisms regulating the expression of these genes, a yeast one-hybrid screening was performed with an elicitor-responsive part of the tdc promoter. this screening identified three members of the cys(2)/ ...200415465826
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
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
a novel hydroxylase from catharanthus roseus participating in the hydroxylation of 2-hydroxybenzoic acid.a novel 55-kda hydroxylase was isolated from cultured cells of catharanthus roseus by a three-step procedure: anion exchange chromatography, affinity chromatography and hydroxylapatite adsorption chromatography. the enzyme specifically catalyzed the hydroxylation of 2-hydroxybenzoic acid to give 2,5-dihydroxybenzoic acid. the enzyme activity was optimal at ph 7.8 and was completely inhibited by divalent cations, such as cu(2+) and hg(2+). the enzyme showed sequence similarity to certain plant fl ...200416233668
enhancement of ajmalicine production in catharanthus roseus cell cultures with methyl jasmonate is dependent on timing and dosage of elicitation.the optimum growth stage for enhancing ajmalicine production in catharanthus roseus cultures with methyl jasmonate (mj) was after 6 d growth. mj added at 10 or 100 microm on day 6 gave a maximum ajmalicine production of 10.2 mg l(-1), a 300% increase over that of non-elicited cultures.200415604804
vindoline synthesis in in vitro shoot cultures of catharanthus roseus.vindoline, the major alkaloid in cultures of catharanthus roseus shoots, reached 2 mg g(-1) dry wt after 27 d in culture. maximal vindoline accumulation coincided with maximum activities of deacetoxyvindoline 4-hydroxylase, deacetylvindoline acetyl-coa acetyl transferase and tryptophan decarboxylase. shoot exposure to jasmonate shortened the time required for the maximal vindoline accumulation to 14 d.200415200179
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
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
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
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 metabolites.in 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
interaction of spermine with a signal transduction pathway involving phospholipase c, during the growth of catharanthus roseus transformed roots.in cantharanthus roseus transformed roots, the application of methylglyoxal bis(guanylhydrazone) (mgbg), an inhibitor of s-adenosylmethionine decarboxylase (samdc; ec 4.1.1.50), 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 3.1.4.3) 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
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
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
metabolic engineering of the indole pathway in catharanthus roseus hairy roots and increased accumulation of tryptamine and serpentine.transgenic hairy roots of catharanthus roseus were established with glucocorticoid inducible tryptophan decarboxylase (tdc) expression alone or in combination with inducible expression of a feedback-resistant anthranilate synthase alpha subunit (asalpha) from arabidopsis. northern blot analysis confirmed transcription of the anthranilate synthase gene upon induction in the double line (tdc+asalpha) and in vitro enzyme assays confirmed increased resistance to feedback inhibition by tryptophan. in ...200415491856
salt-induced lipid changes in catharanthus roseus cultured cell suspensions.salt treatment strongly affected cell growth by decreasing dry weight. exposure of catharanthus roseus cell suspensions to increasing salinity significantly enhanced total lipid (tl) content. the observed increase is mainly due to high level of phospholipids (pl). hundred mm nacl treatment increased phospholipid species phosphatidylcholine (pc) and phosphatidylethanolamine (pe), whereas it reduced glycolipid ones monogalactosyldiacylglycerol (mgdg) and digalactosyldiacylglycerol (dgdg) but not s ...200415279997
alkaloid accumulation in catharanthus roseus cell suspension cultures fed with stemmadenine.feeding stemmadenine to catharanthus roseus cell suspension culture resulted in the accumulation of catharanthine, tabersonine and condylocarpine. condylocarpine is not an intermediate in the pathway to catharanthine or tabersonine when it is fed to the cultures. the results support the hypothesis that stemmadenine is an intermediate in the pathway to catharanthine and tabersonine.200415269549
novel bisindole derivatives of catharanthus alkaloids with potential cytotoxic properties.pantropical plant catharanthus roseus (l) g. don is known as a source of valuable bisindole alkaloids: vinblastine (vbl) and vincristine (vcr), oncolytics widely used as sulfates in therapy of malignant diseases. they are biosynthesized in the plant from monoindolic vindoline and catharanthine, both derived from l-tryptophan and loganine units. in the course of phytochemical screening of this plant cultivated in poland and considered as a home source of vbl and vcr we developed a new isolation m ...200315206784
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
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
immunocytolocalization of tryptophan decarboxylase in catharanthus roseus hairy roots.we investigated the intracellular distribution of tryptophan decarboxylase (tdc) (ec 4.1.1.28) 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
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
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
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
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
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
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
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
[advances in the study of vincristine: an anticancer ingredient from catharanthus roseus].vincristine is a dimer-indo-alkaloid which is extracted from the leaves of catharanthus roseus. it is effective to treat acute lymphocytic cell leukemia, hodgkin disease and non-hodgkin disease clinically. but the severe side effects, such as neurotoxic and tissue damage, limit its application. in this paper, we summarize physical, chemical, pharmacological and pharmacokinetical properties of vcr and advances in decreasing its side effects. in clinic, association with other medication is adopted ...200315615402
[industrialization of medicinal plant tissue culture].compared with other countries, the industrialization of medicinal plant tissue culture is more important for our country because china is consuming and exporting the most amounts of herb materials in the world. each year, many papers and patents are published on cell cultures of popular medicinal plants, such as taxus sp., catharanthus roseus, and panax ginseng, and, meanwhile, the research on organ cultures of medicinal plants is increasing very quickly, which is deepening the study of medicina ...200315139118
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
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
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
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
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
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
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
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
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
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 1.1.1.88) 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
biosynthesis of cholestanol in higher plants.to 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
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
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
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 diseases.an 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
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
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
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
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
production of 5'-phosphodiesterase by catharanthus roseus cells promoted by heat-degraded products generated from uronic acid.polyalginate was autoclaved at 121 degrees c for 20 min and its molecular weight distribution was analyzed. the autoclaved alginate yielded alginate polymer, oligomer and heat degraded products (hdps). each of the separated substances promoted 5'-phosphodiesterase (5'-pdase) production in suspension culture of catharanthus roseus cells. hdps could also be generated from other uronic acids (galacturonic acid and glucuronic acid) by autoclave treatment. the most effective substance in the hdps was ...200216233285
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
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
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