Publications

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 ...	2002	12237558
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 ...	2002	12115404
tryptophan decarboxylase from transformed roots of catharanthus roseus.	tryptophan decarboxylase (tdc, ec 4.1.1.28) 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 ...	2002	12102544
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 ...	2002	12061566
effect of precursor feeding on alkaloid accumulation by a tryptophan decarboxylase over-expressing transgenic cell line t22 of catharanthus roseus.	to 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 ...	2002	12039535
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 ...	2002	12011178
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 ...	2001	11817539
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 ...	2001	11562272
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. ...	2001	11525616
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, ...	2001	11513416
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 ...	2001	11458587
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. ...	2001	11404355
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 ...	2001	11352466
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 ...	2001	11572396
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 ...	2001	11352226
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 ...	2001	11339952
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 ...	2001	11339951
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 ...	2001	11255514
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 ...	2001	11241768
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 ...	2001	12806432
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 ...	2001	11922593
[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, ...	2001	11233258
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 ...	2001	11319239
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.	2001	11397432
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 ...	2001	11448549
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 ...	2001	11549013
molecular and biochemical analysis of a madagascar periwinkle root-specific minovincinine-19-hydroxy-o-acetyltransferase.	the terminal steps in the biosynthesis of the monoterpenoid indole alkaloids vindoline and minovincinine are catalyzed by separate acetyl coenzyme a-dependent o-acetyltransferases in madagascar periwinkle (catharanthus roseus g. don). two genes were isolated that had 63% nucleic acid identity and whose deduced amino acid sequences were 78% identical. active enzymes that were expressed as recombinant his-tagged proteins in escherichia coli were named minovincinine-19-o-acetyltransferase (mat) and ...	2001	11154328
the jasmonate-inducible ap2/erf-domain transcription factor orca3 activates gene expression via interaction with a jasmonate-responsive promoter element.	the ap2/erf-domain transcription factor orca3 is a master regulator of primary and secondary metabolism in catharanthus roseus (periwinkle). here we demonstrate that orca3 specifically binds to and activates gene expression via a previously characterized jasmonate- and elicitor-responsive element (jere) in the promoter of the terpenoid indole alkaloid biosynthetic gene strictosidine synthase (str). functional characterization of different domains in the orca3 protein in yeast and plant cells rev ...	2001	11169181
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 ...	2001	11714298
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 ...	2001	11718718
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 ...	2001	11722126
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 ...	2001	11204786
nonphytotoxic aluminum-peat complexes suppress phytophthora parasitica.	abstract amendment of peat-based potting media with al(2)(so(4))(3) suppresses damping-off of vinca (catharanthus roseus) caused by phytophthora parasitica. the species of aluminum (al) responsible for disease suppression have not been identified. the objective of this study was to determine the effects of amount and ph of al(2)(so(4))(3) amendment solutions on survival of p. parasitica. in separate experiments, peat was amended with al(2)(so(4))(3) solutions adjusted to ph 4 or 6 at either 0.01 ...	2001	18943446
effects of solarization and ammonium amendments on plant-parasitic nematodes.	the effects of soil solarization and ammonium bicarbonate or ammonium sulfate against plant-parasitic nematodes on yellow squash (cucurbita pepo) and on vinca (catharanthus roseus) were evaluated at two sites. solarization for 3 weeks in the spring suppressed population levels of belonolaimus longicaudatus, criconemella spp., and dolichodorus heterocephalus throughout the growing season on both crops at both sites. levels of meloidogyne incognita were suppressed initially, but population densiti ...	2000	19271007
[studies on the biosynthesis of sterol side chain in higher plants].	campesterol (3) and dihydrobrassicasterol (4), typical c28-sterols in higher plants, are biosynthesized from a steroidal 24-ene precursor (desmosterol 1) via 24-methylenecholesterol (2) and 24-methyldesmosterol (5). a typical plant c29-sterol, sitosterol (6), is produced from 24-methylenecholesterol via isofucosterol (7) and 24-ethyldesmosterol (8). the biosynthetic mechanism, focussing stereochemical features, of these side-chain transformations has been studied in detail by feeding regio- and ...	2000	11082699
a catharanthus roseus bpf-1 homologue interacts with an elicitor-responsive region of the secondary metabolite biosynthetic gene str and is induced by elicitor via a ja-independent signal transduction pathway.	plants respond to pathogen attack by induction of various defence responses, including the biosynthesis of protective secondary metabolites. in catharanthus roseus, the elicitor-induced expression of the terpenoid indole alkaloid biosynthetic gene strictosidine synthase (str) is mediated via the plant stress hormonejasmonate. in the promoters of several defence-related genes, cis-acting elements have been identified that are important for transcriptional regulation upon stress signals. here we s ...	2000	11198427
molecular cloning and analysis of strictosidine beta-d-glucosidase, an enzyme in terpenoid indole alkaloid biosynthesis in catharanthus roseus.	strictosidine beta-d-glucosidase (sgd) is an enzyme involved in the biosynthesis of terpenoid indole alkaloids (tias) by converting strictosidine to cathenamine. the biosynthetic pathway toward strictosidine is thought to be similar in all tia-producing plants. somewhere downstream of strictosidine formation, however, the biosynthesis diverges to give rise to the different tias found. sgd may play a role in creating this biosynthetic diversity. we have studied sgd at both the molecular and enzym ...	2000	10652285
histopathology and polyphenol content in plants infected by phytoplasmas.	the alterations of cell walls and the localization of several compounds such as polyphenols, suberin, lignin, in plum and apple plants infected with plum leptonecrosis (pln) and apple proliferation (ap) phytoplasmas respectively, were investigated. catharanthus roseus plants, infected with ap or pln were also studied. the 4,6-diamidino-2-phenylindole (dapi) test and transmission electron microscopy showed the presence of phytoplasmas in all infected plants. specific histological stainings for cu ...	2000	10969878
plant methionine synthase: new insights into properties and expression.	we investigated the enzyme methionine synthase (msy) in catharanthus roseus. the properties were characterized with purified protein isolated either from plant cell cultures or after heterologous expression in escherichia coli. the protein was a monomer and accepted both the triglutamate (ch3-h4pteglu3, apparent km = 80 microm) and the monoglutamate (ch3-h4pteglu1, apparent km = 350 microm) of methyl-5,6,7,8-tetrahydropteroate as methyl donor, with a ratio of approximately 90:1 in favor of the t ...	2000	11030427
the ternary transformation system: constitutive virg on a compatible plasmid dramatically increases agrobacterium-mediated plant transformation.	this paper describes a so-called ternary transformation system for plant cells. we demonstrate that agrobacterium tumefaciens strain lba4404 supplemented with a constitutive virg mutant gene (virgn54d) on a compatible plasmid is capable of very efficient t-dna transfer to a diverse range of plant species. for the plant species catharanthus roseus it is shown that increased t-dna transfer results in increased stable transformation frequencies. analysis of stably transformed c. roseus cell lines s ...	2000	11052201
cloning and expression of cdnas encoding two enzymes of the mep pathway in catharanthus roseus.	two periwinkle cdnas (crdxr and crmecs) encoding enzymes of the non-mevalonate terpenoid pathway were characterized using reverse transcription-pcr strategy based on the design of degenerated oligonucleotides. the deduced amino acid sequence of crdxr is homologue to 1-deoxy-d-xylulose 5-phosphate reductoisomerases. crmecs represents the first plant cdna encoding a protein similar to the 2c-methyl-d-erythritol 2,4-cyclodiphosphate synthase from escherichia coli. expression of crdxr and crmecs gen ...	2000	11118631
indole alkaloid biosynthesis in catharanthus roseus: new enzyme activities and identification of cytochrome p450 cyp72a1 as secologanin synthase.	the molecular characterization of cyp72a1 from catharanthus roseus (madagascar periwinkle) was described nearly a decade ago, but the enzyme function remained unknown. we now show by in situ hybridization and immunohistochemistry that the expression in immature leaves is epidermis-specific. it thus follows the pattern previously established for early enzymes in the pathway to indole alkaloids, suggesting that cyp72a1 may be involved in their biosynthesis. the early reactions in that pathway, i.e ...	2000	11135113
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.	2000	11449504
28-norcastasterone is biosynthesized from castasterone.	metabolic experiments with deuterium-labeled castasterone in seedlings of arabidopsis thaliana, oryza saliva and lycopersicon esculentum, and cultured cells of catharanthus roseus were performed, and the metabolites were analyzed by gc-ms. in all the plant species examined, [2h3]28-norcastasterone was identified as a metabolite of [26,28-2h6]castasterone, indicating that castasterone is the biosynthetic origin of 28-norcastasterone. moreover, the natural occurrence of 28-norcastasterone and 28-n ...	2000	11065283
light activation of vindoline biosynthesis does not require cytomorphogenesis in catharanthus roseus seedlings.	upon illumination, the cotyledons of catharanthus roseus seedlings readily synthesise vindoline from late biosynthetic intermediates, which accumulate in etiolated seedlings. the cellular localisation of tryptophan decarboxylase (tdc) and desacetoxyvindoline 4-hydroxylase (d4h), which catalyse the first and penultimate reactions of vindoline biosynthesis, was identified by immunocytochemistry in developing seedlings. the expression of tdc was restricted to the upper epidermis of cotyledons, wher ...	2000	11130662
phosphate uptake across the tonoplast of intact vacuoles isolated from suspension-cultured cells of catharanthus roseus (l.) g. don.	transport of inorganic orthophosphate (pi) across the tonoplast membrane was studied using intact vacuoles isolated from suspension-cultured cells of catharanthus roseus. orthophosphate uptake was strongly stimulated in the presence of mg-atp and mg-pyrophosphate and inhibited by bafilomycin and concanamycin which are potent inhibitors of the vacuolar h+-atpase. these results indicated that the build-up of an electrochemical gradient by the h - pumps was essential for the uptake of pi. potassium ...	2000	10987558
purification and characterization of mevalonate kinase from suspension-cultured cells of catharanthus roseus (l.) g. don.	mevalonate kinase was purified to homogeneity from catharanthus roseus (l.) g. don suspension-cultured cells. the purified enzyme had an m(r) of 104,600 and a subunit size of about 41,500. kinetic studies indicated an ordered sequential mechanism of action, in which mevalonate was the first substrate to bind and adp was the last product to leave the enzyme. true values for the kinetic constants were determined for mevalonate, with k(ma) = 76 microm and k(ia) = 74 microm, and for atp, with k(mb) ...	2000	10860546
regulation of cytoplasmic ph under extreme acid conditions in suspension cultured cells of catharanthus roseus: a possible role of inorganic phosphate.	changes in cytoplasmic ph of suspension-cultured cells of catharanthus roseus under extreme acid conditions were measured with the ph-dependent fluorescence dye; 2',7'-bis-(2-carboxyethyl)-5 (and-6) carboxyfluorescein (-acetoxymethylester) (bcecf). when cells were treated with 1 mm hcl (ph 3 solution), the cytoplasmic ph first decreased then returned to the original level. treatment with 10 mm hcl (ph 2 solution) acidified the cytoplasm to a greater extent, and the acidification continued at a c ...	2000	10845455
determination of metabolic rate-limitations by precursor feeding in catharanthus roseus hairy root cultures.	precursors from the terpenoid and tryptophan branches were fed to catharanthus roseus to determine which of the two branches limits metabolic flux to indole alkaloids. the feeding of tryptophan at 17 days of the culture cycle produced auxin-like effects. addition of low levels of auxin or tryptophan resulted in significant increases in flux to the indole alkaloids. conversely, feeding higher levels of auxin or tryptophan resulted in increased branching and thickening of the hairy root cultures. ...	2000	10812182
effects of buffered media upon growth and alkaloid production of catharanthus roseus hairy roots.	the influence of buffered media upon the growth and alkaloid productivity of catharanthus roseus hairy root culture was examined. as expected, the buffers minimized shifts in the ph of the media and had slightly negative effects upon growth. the growth of the hairy roots remained optimal in unbuffered media. the specific yield of lochnericine was significantly lower in response to the addition of buffers, while tabersonine was significantly higher. in contrast, the specific yields of ajmalicine, ...	2000	10772463
biosynthesis of brassinosteroids in cultured cells of catharanthus roseus.	precursor administration experiments with 2h-labeled 6-oxocampestanol, 6-deoxocastasterone and 6alpha-hydroxycastasterone in cultured cells of catharanthus roseus were performed and the metabolites were analyzed by gc-ms. [2h6]cathasterone was identified as a metabolite of [2h6]6-oxocampestanol, whereas [2h6]6alpha-hydroxycastasterone and [2h6]castasterone were identified as metabolites of [2h6]6-deoxocastasterone, and [2h6]castasterone was identified as a metabolite of [2h6]6alpha-hydroxycastas ...	2000	10724179
the effect of inoculum density and conditioned medium on the production of ajmalicine and catharanthine from immobilized catharanthus roseus cells.	the effect of the cell-inoculum size and the addition of conditioned medium on ajmalicine and catharanthine production were studied using immobilized catharanthus roseus cells. higher specific-uptake rates of ammonium, nitrate, and sugars were observed in the low-inoculum-density cultures (50 g fw/l) compared to the high-inoculum-density cultures (100 g fw/l). alkaloid production was not correlated with the exhaustion of a particular nutrient from the medium. the high-inoculum-density cultures p ...	2000	10581436
orca3, a jasmonate-responsive transcriptional regulator of plant primary and secondary metabolism.	biosynthesis of many classes of secondary metabolites in plants is induced by the stress hormone jasmonate. the gene for orca3, a jasmonate-responsive apetala2 (ap2)-domain transcription factor from catharanthus roseus, was isolated by transferred dna activation tagging. orca3 overexpression resulted in enhanced expression of several metabolite biosynthetic genes and, consequently, in increased accumulation of terpenoid indole alkaloids. regulation of metabolite biosynthetic genes by jasmonate-r ...	2000	10894776
multicellular compartmentation of catharanthus roseus alkaloid biosynthesis predicts intercellular translocation of a pathway intermediate	in situ rna hybridization and immunocytochemistry were used to establish the cellular distribution of monoterpenoid indole alkaloid biosynthesis in madagascar periwinkle (catharanthus roseus). tryptophan decarboxylase (tdc) and strictosidine synthase (str1), which are involved in the biosynthesis of the central intermediate strictosidine, and desacetoxyvindoline 4-hydroxylase (d4h) and deacetylvindoline 4-o-acetyltransferase (dat), which are involved in the terminal steps of vindoline biosynthes ...	1999	10330473
microplate enzyme-coupled assays of mevalonate and phosphomevalonate kinase from catharanthus roseus suspension cultured cells.	a microplate assay for mevalonate and 5-phosphomevalonate kinase activities has been developed using an enzyme-coupled system of pyruvate kinase and lactate dehydrogenase. mevalonate and 5-phosphomevalonate kinase activities were measured in crude and partially purified enzyme preparations from catharanthus roseus suspension-cultured plant cells. the assay was validated with respect to protein and substrate concentration. mevalonate and 5-phosphomevalonate kinase showed michaelis-menten kinetics ...	1999	10221996
a simple structured model for maintenance, biomass formation, and ajmalicine production by nondividing catharanthus roseus cells.	the stoichiometry of maintenance and carbohydrate storage as well as ajmalicine production kinetics of non-dividing catharanthus roseus cells in the second stage of a two-stage batch process were investigated. for the mathematical description of these processes, a simple structured model with 5 parameters is proposed. in the model the biomass is divided in two compartments: active biomass and storage carbohydrates. in induction medium (standard medium without phosphate, nitrogen and hormones), b ...	1999	10577468
isolation of indole alkaloids from catharanthus roseus by centrifugal partition chromatography in the ph-zone refining mode.	centrifugal partition chromatography (cpc) in the ph-zone refining mode allowed a preparative and efficient isolation of vindoline, vindolinine, catharanthine and vincaleukoblastine from a crude mixture of catharanthus roseus alkaloids. the separation protocol was tested with a synthetic mixture of vindoline, catharanthine and vincaleukoblastine. the fraction content was analyzed and the results compared with theoretical chromatograms obtained by numerical simulation. the increase in injected sa ...	1999	10457440
purification of xyloglucan endotransglycosylase based on affinity sorption of the active glycosyl-enzyme intermediate complex to cellulose.	xyloglucan endotransglycosylase (xet) catalyzes the cleavage of xyloglucan (xg) molecules by a transglycosylation mechanism involving two steps: (a) endocleavage of the beta-(1,4)-linked polyglucosyl backbone of the xyloglucan molecule with formation of a glycosyl-enzyme intermediate; (b) transfer of the glycosyl residue from the intermediate to the c-4 position of the nonreducing end glucosyl unit of another molecule of xg or an xg-derived oligosaccharide with liberation of the enzyme (z. sulov ...	1999	10419819
arabidopsis det2 is defective in the conversion of (24r)-24-methylcholest-4-en-3-one to (24r)-24-methyl-5alpha-cholestan-3-one in brassinosteroid biosynthesis.	previously, we have shown that the arabidopsis det2 (deetiolated2) mutant is defective in the biosynthesis of brassinosteroids (br) and that det2 (a steroid 5alpha-reductase) acts early in the proposed br biosynthetic pathway. in this paper we present further biochemical characterization of det2. we have undertaken metabolic experiments with 2h-labeled substrates of intermediates involved in the formation of campestanol from campesterol, and quantitative analysis of intermediates in arabidopsis ...	1999	10398719
alkaloid accumulation in catharanthus roseus suspension cultures.		1999	10081005
dimethylallyl pyrophosphate is not the committed precursor of isopentenyl pyrophosphate during terpenoid biosynthesis from 1-deoxyxylulose in higher plants.	cell cultures of catharanthus roseus were supplied with [2-13c, 3-2h]-deoxyxylulose or [2-13c,4-2h]1-deoxyxylulose. lutein and chlorophylls were isolated from the cell mass, and hydrolysis of the chlorophyll mixtures afforded phytol. isotope labeling patterns of phytol and lutein were determined by 2h nmr and 1h,2h-decoupled 13c nmr. from the data it must be concluded that the deuterium atom in position 3 of deoxyxylulose was incorporated into both isopentenyl pyrophosphate (ipp) and dimethylall ...	1999	9990020
in vivo 31p and multilabel 13c nmr measurements for evaluation of plant metabolic pathways.	reliable measurements of intracellular metabolites are useful for effective plant metabolic engineering. this study explored the application of in situ 31p and 13c nmr spectroscopy for long-term measurements of intracellular ph and concentrations of several metabolites in glycolysis, glucan synthesis, and central carbon metabolic pathways in plant tissues. an nmr perfusion reactor system was designed to allow catharanthus roseus hairy root cultures to grow for 3-6 weeks, during which time nmr sp ...	1999	10935751
development of an apparatus for monitoring protoplast isolation from plant tissues based on both dielectric and optical methods.	in order to develop a method allowing objective determination of the optimal conditions for the isolation of protoplasts, the process of protoplast isolation from plant tissues was quantitatively evaluated. first, a specialized spectrophotometer cuvette (working volume = 2.0 ml) was designed for the continuous monitoring of protoplast isolation from plant tissues based on the optical method. homogeneous mixing of tissue sections and the protoplast suspension in the cuvette was accomplished by me ...	1999	16232551
identification of uv-b light-responsive regions in the promoter of the tryptophan decarboxylase gene from catharanthus roseus.	the tryptophan decarboxylase (tdc) gene encodes a key enzyme in the biosynthesis of terpenoid indole alkaloids (tias) in catharanthus roseus. tias absorb ultraviolet light (uv) and putative functions in plants include a role as uv protectants. in support of this possible function we demonstrate here that uv light induces accumulation of several tias as well as expression of the tdc gene in c. roseus. in addition, in tobacco a tdc-gusa construct was found to be specifically induced by uv-b light. ...	1999	10608659
involvement of the octadecanoid pathway and protein phosphorylation in fungal elicitor-induced expression of terpenoid indole alkaloid biosynthetic genes in catharanthus roseus	two key genes in terpenoid indole alkaloid biosynthesis, tdc and str, encoding tryptophan decarboxylase and strictosidine synthase, respectively, are coordinately induced by fungal elicitors in suspension-cultured catharanthus roseus cells. we have studied the roles of the jasmonate biosynthetic pathway and of protein phosphorylation in signal transduction initiated by a partially purified elicitor from yeast extract. in addition to activating tdc and str gene expression, the elicitor also induc ...	1999	10198087
the promoter of the strictosidine synthase gene from periwinkle confers elicitor-inducible expression in transgenic tobacco and binds nuclear factors gt-1 and gbf.	strictosidine synthase (str) is a key enzyme in the biosynthesis of terpenoid indole alkaloids. this class of secondary metabolites harbours several pharmaceutically important compounds used, among other applications, in cancer treatment. terpenoid indole alkaloid biosynthesis and expression of biosynthetic genes including str1 is induced by fungal elicitors. to identify elicitor-responsive regulatory promoter elements and trans-acting factors, the single-copy str1 gene was isolated from the sub ...	1999	10380815
structural and kinetic properties of adenylyl sulfate reductase from catharanthus roseus cell cultures.	a cdna encoding a plant-type aps reductase was isolated from an axenic cell suspension culture of catharanthus roseus (genbank/embl-databank accession number u63784). the open reading frame of 1392 bp (termed par) encoded for a protein (mr=51394) consisting of a n-terminal transit peptide, a paps reductase-like core and a c-terminal extension with homology to the thioredoxin-like domain of protein disulfide isomerase. the aps reductase precursor was imported into pea chloroplasts in vitro and pr ...	1999	10082930
nuclear factors gt-1 and 3af1 interact with multiple sequences within the promoter of the tdc gene from madagascar periwinkle: gt-1 is involved in uv light-induced expression.	plant secondary metabolites of the terpenoid indole alkaloid (tia) class comprise several compounds with pharmaceutical applications. a key step in the tia biosynthetic pathway is catalysed by the enzyme tryptophan decarboxylase (tdc), which channels the primary metabolite tryptophan into tia metabolism. in catharanthus roseus (madagascar periwinkle), the tdc gene is expressed throughout plant development. moreover, tdc gene expression is induced by external stress signals, such as fungal elicit ...	1999	10394897
a novel jasmonate- and elicitor-responsive element in the periwinkle secondary metabolite biosynthetic gene str interacts with a jasmonate- and elicitor-inducible ap2-domain transcription factor, orca2.	jasmonate (ja) is an important plant stress hormone that induces various plant defense responses, including the biosynthesis of protective secondary metabolites. the induction of the secondary metabolite biosynthetic gene strictosidine synthase (str) in catharanthus roseus (periwinkle) cells by elicitor requires ja as a second messenger. a 42 bp region in the str promoter is both necessary and sufficient for ja- and elicitor-responsive expression. this region is unlike other previously identifie ...	1999	10449411
elicitor-responsive promoter regions in the tryptophan decarboxylase gene from catharanthus roseus.	the tryptophan decarboxylase (tdc) gene from catharanthus roseus (madagascar periwinkle) encodes a key enzyme in biosynthesis of terpenoid indole alkaloids. the expression of the tdc gene is transcriptionally induced by fungal elicitors. tdc upstream sequences from -1818 to +198 relative to the transcriptional start site were functionally analysed to identify cis-acting elements that determine basal expression or respond to elicitor. in a loss-of-function analysis promoter derivatives with 5' or ...	1999	10080715
a g-box element from the catharanthus roseus strictosidine synthase (str) gene promoter confers seed-specific expression in transgenic tobacco plants.	the enzyme encoded by the strictosidine synthase (str) gene from catharanthus roseus catalyses a key step in the biosynthesis of the pharmaceutically important terpenoid indole alkaloids. str cdna and genomic clones have already been isolated, allowing us to study the regulation of str gene expression. here we focus on the role of a putative cis-acting element, cacgtg, in the str promoter. this sequence is known as a g-box, and functions as a transcription-regulating sequence in a number of othe ...	1999	10394900
flavonoid hydroxylase from catharanthus roseus: cdna, heterologous expression, enzyme properties and cell-type specific expression in plants.	we investigated the p450 dependent flavonoid hydroxylase from the ornamental plant catharanthus roseus. cdnas were obtained by heterologous screening with the cyp75 hf1 cdna from petunia hybrida. the c. roseus protein shared 68-78% identity with other cyp75s, and genomic blots suggested one or two genes. the protein was expressed in escherichia coli as translational fusion with the p450 reductase from c. roseus. enzyme assays showed that it was a flavonoid 3', 5'-hydroxylase, but 3'-hydroxylated ...	1999	10476065
light-induced cytochrome p450-dependent enzyme in indole alkaloid biosynthesis: tabersonine 16-hydroxylase.	vinblastine and vincristine are two medically important bisindole alkaloids from catharanthus roseus (madagascar periwinkle). attempts at production in cell cultures failed because a part of the complex pathway was not active, i.e. from tabersonine to vindoline. it starts with tabersonine 16-hydroxylase (t16h), a cytochrome p450-dependent enzyme. we now show that t16h is induced in the suspension culture by light and we report the cloning of the cdna. the enzyme was expressed in escherichia coli ...	1999	10481044
gene disruption through homologous recombination in spiroplasma citri: an scm1-disrupted motility mutant is pathogenic.	to determine whether homologous recombination could be used to inactivate selected genes in spiroplasma citri, plasmid constructs were designed to disrupt the motility gene scm1. an internal scm1 gene fragment was inserted into plasmid pkt1, which replicates in escherichia coli but not in s. citri, and into the s. citri oric plasmid pbot1, which replicates in spiroplasma cells as well as in e. coli. electrotransformation of s. citri with the nonreplicative, recombinant plasmid pktm1 yielded no t ...	1999	10601200
a comparative evaluation of some blood sugar lowering agents of plant origin.	a comparison of blood sugar lowering activity of four important medicinal plants (azadirachta indica, gymnema sylvestre, catharanthus roseus and ocimum sanctum) were carried out against normal and streptozotocin-induced diabetic rat models. the plant extracts decreased the blood sugar level in varying degrees. blood sugar lowering unit (blu) of activity of each leaf extract and tolbutamide was calculated by ed50 values. statistical analysis revealed significant (p < 0.05) variation among the tre ...	1999	10617074
subcellular localization of the coat protein in tobacco cells infected by cucumber mosaic virus isolated from catharanthus roseus.	electron microscopy and immunolabelling with antiserum specific to cucumber mosaic virus coat protein were used to examine tobacco leaf cells infected by cucumber mosaic virus isolated from catharanthus roseus (cmv-cr). crystalline and amorphous inclusions in the vacuoles were the most obvious cytological modifications seen. immunogold labelling indicated that the crystalline inclusion was made up of virus particles and amorphous inclusions contained coat protein. rows of cmv-cr particles were f ...	1999	10643647
kinetic analysis of phospholipase c from catharanthus roseus transformed roots using different assays	the properties of phospholipase c (plc) partially purified from catharanthus roseus transformed roots were analyzed using substrate lipids dispersed in phospholipid vesicles, phospholipid-detergent mixed micelles, and phospholipid monolayers spread at an air-water interface. using [(33)p]phosphatidylinositol 4,5-bisphosphate (pip(2)) of high specific radioactivity, plc activity was monitored directly by measuring the loss of radioactivity from monolayers as a result of the release of inositol ph ...	1999	10444091
purification and cdna cloning of isochorismate synthase from elicited cell cultures of catharanthus roseus.	isochorismate is an important metabolite formed at the end of the shikimate pathway, which is involved in the synthesis of both primary and secondary metabolites. it is synthesized from chorismate in a reaction catalyzed by the enzyme isochorismate synthase (ics; ec 5.4.99.6). we have purified ics to homogeneity from elicited catharanthus roseus cell cultures. two isoforms with an apparent molecular mass of 64 kd were purified and characterized. the km values for chorismate were 558 and 319 micr ...	1999	9952467
causal role of xylella fastidiosa in oleander leaf scorch disease.	abstract a lethal leaf scorch disease of oleander (nerium oleander) appeared in southern california in 1993. a bacterium, xylella fastidiosa, was detected by culturing, enzyme-linked immunoassay, and polymerase chain reaction in most symptomatic plants but not in symptomless plants or negative controls. inoculating oleanders mechanically with x. fastidiosa cultures from diseased oleanders caused oleander leaf scorch (ols) disease. the bacterium was reisolated from inoculated plants that became d ...	1999	18944803
pathogenicity of aster yellows phytoplasma and spiroplasma citri on periwinkle.	abstract using murashige and skoog (ms) as a basal medium, the effects of varying levels and combinations of plant growth regulators required for shoot tip and root proliferation in healthy and aster yellows phytoplasma (ayp)- and spiroplasma citri-infected periwinkle (catharanthus roseus) shoots were studied. number of shoots and fresh and dry mass of healthy and ayp-infected shoots increased when benzyladenine (ba) concentrations were increased from 0.5 to 4 mg/liter. the maximum number of sho ...	1998	18944838
detergent-solubilized nadph-cytochrome c(p-450) reductase from the higher plant, catharanthus roseus. purification and characterization.		1998	107158
a novel cis-acting element in promoters of plant b-type cyclin genes activates m phase-specific transcription.	plant b-type cyclin genes are expressed late in the g2 and m phases of the cell cycle. previously, we showed that the promoter of a catharanthus roseus b-type cyclin, cym, could direct m phase-specific transcription of a beta-glucuronidase reporter gene in synchronously dividing by2 tobacco cells. in this study, we determined the regulatory elements contained within the cym promoter by using a luciferase reporter gene. mutational analysis showed that a 9-bp element is essential for m phase-speci ...	1998	9501108
glyphosate is an inhibitor of plant cytochrome p450: functional expression of thlaspi arvensae cytochrome p45071b1/reductase fusion protein in escherichia coli.	glyphosate (roundup) is an herbicide used extensively worldwide which acts as an inhibitor of 5'enolpyruvylshikimate-3-phosphate synthase and for which transgenic herbicide resistant plants have been developed. here we report for the first time that glyphosate is an inhibitor of cytochrome p450 using a functional expression system for thlaspi arvensae cyp71b1 in escherichia coli. cyp71b1 was fused to the soluble domain of a plant cytochrome p450 reductase (cpr) from catharanthus roseus. cyp71b1 ...	1998	9514851
effects of over-expression of strictosidine synthase and tryptophan decarboxylase on alkaloid production by cell cultures of catharanthus roseus.	cells of catharanthus roseus (l.) g. don were genetically engineered to over-express the enzymes strictosidine synthase (str; ec 4.3.3.2) and tryptophan decarboxylase (tdc; ec 4.1.1.28), which catalyze key steps in the biosynthesis of terpenoid indole alkaloids (tias). the cultures established after agrobacterium-mediated transformation showed wide phenotypic diversity, reflecting the complexity of the biosynthetic pathway. cultures transgenic for str consistently showed tenfold higher str activ ...	1998	9640666
effect of different inhibitors on phospholipase c activity in catharanthus roseus transformed roots.	we have previously reported that catharanthus roseus transformed roots contain at least two phosphatidylinositol 4,5-bisphosphate-phospholipase c (plc) activities, one soluble and one membrane associated. in this paper, the effect of neomycin and several divalent cations was analyzed, both in the soluble and the membrane-associated plc activity in c. roseus transformed roots. in this system, neomycin, an aminoglycoside antibiotic, inhibited plc in a concentration-dependent fashion. the neomycin ...	1998	9674018
expression of two consecutive genes of a secondary metabolic pathway in transgenic tobacco: molecular diversity influences levels of expression and product accumulation.	we have created a population of transgenic tobacco plants carrying cdnas encoding two consecutive enzymes from early stages in monoterpenoid alkaloid biosynthesis in catharanthus roseus. the cdnas, encoding tryptophan decarboxylase (tdc) and strictosidine synthase (str1) together with a selectable marker gene, were introduced on a single transforming plasmid into tobacco leaves by particle bombardment. analysis of 150 independent transgenic plants at the dna and rna levels demonstrated a range o ...	1998	9862494
evidence of protein-tyrosine kinase activity in catharanthus roseus roots transformed by agrobacterium rhizogenes.	homogenate fractions (soluble and particulate) from transformed roots of catharanthus roseus (l.) g. don showed several phosphorylated proteins when incubated with gamma-[32p]atp. the phosphorylation in the proteins of 55, 40, 25, 18 and 10 kda in the particulate fraction and 63 kda in the soluble fraction was resistant to alkali treatment. several proteins in both fractions gave a positive signal with monoclonal antiphosphotyrosine antibodies. in-situ phosphorylation in both fractions showed se ...	1998	9443385
brassinosteroids in arabidopsis thaliana.	from the seeds and siliques of arabidopsis thaliana, six brassinosteroids, brassinolide, castasterone, typhasterol, 6-deoxocastasterone, 6-deoxotyphasterol and 6-deoxoteasterone, were identified by gc-mass spectrometry or gc-selected ion monitoring. as the occurrence of castasterone, typhasterol, 6-deoxocastasterone and 6-deoxotyphasterol in the shoots of a. thaliana has already been reported, this study provides evidence for the occurrence of the above four brassinosteroids in different organs, ...	1998	9664702
rapid in vitro multiplication of plants from mature nodal explants of catharanthus roseus.		1998	17253257
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 ...	1998	11672355
transient studies of light-adapted cultures of hairy roots of catharanthus roseus: growth and indole alkaloid accumulation.	cultures of c. roseus transgenic ("hairy") root clones lbe-6-1 and lbe-4-2 were adapted with periodic daily illumination to investigate the effect of light on growth and nutrient utilization, and the accumulation of the indole alkaloids. light-adapted roots appeared green and had radially thickened morphology compared with dark-grown controls. their growth rates were higher than dark-grown controls, with 45% lower doubling times: lbe-6-1, 3.6 days; lbe-4-2, 2.8 days. relative to dark-grown contr ...	1998	10099477
[new antitumor derivatives of vinblastine].	the alkaloids of catharanthus roseus vincristine 1 and vinblastine 2 are widely used in the chemotherapy of cancer. their nitro-derivatives have also antitumour activity [2]. the dinitro-derivatives 4, 6-9 were prepared for pharmacological investigation. some new hydroxymethyl derivatives 12-14, 17-18, 23-24 of the antitumour indole-indoline alkaloids vinblastine 2 and leurosine 5 were synthetised in two different ways a) by the selective reduction of 2, 5 or deacetoxy-vinblastine 16, b) by the ...	1998	9592933
influence of precursor availability on alkaloid accumulation by transgenic cell line of catharanthus roseus	we have used a transgenic cell line of catharanthus roseus (l.) g. don to study the relative importance of the supply of biosynthetic precursors for the synthesis of terpenoid indole alkaloids. line s10 carries a recombinant, constitutively overexpressed version of the endogenous strictosidine synthase (str) gene. various concentrations and combinations of the substrate tryptamine and of loganin, the immediate precursor of secologanin, were added to suspension cultures of s10. our results indica ...	1998	9490777
expression of extensin genes is dependent on the stage of the cell cycle and cell proliferation in suspension-cultured catharanthus roseus cells.	to isolate cdnas expressed at a specific phase of the cell cycle in a higher plant, we performed differential screening of a cdna library prepared from the s-phase cells of synchronized cultures of catharanthus roseus. sequence analysis shows that two of the identified cdnas, cyc15 and cyc17, encode extensins that represent a family of cell wall hydroxyproline-rich glycoproteins. protein sequences deduced from the two cdnas contain the characteristic pentapeptide repeat sequence, ser-pro-pro-pro ...	1998	9484475
direct fluorometry of phase-extracted tryptamine-based fast quantitative assay of l-tryptophan decarboxylase from catharanthus roseus leaf.	an assay for the enzyme l-tryptophan decarboxylase (tdc; ec 4.1.1.28) is described. it is based on direct fluorometry of the enzymatic reaction product (tryptamine) selectively recovered in ethyl acetate from the reaction mixture. catalytically formed tryptamine from tryptophan in the incubation mixture is selectively (free from tryptophan) physically separated as ethyl acetate solution under basic (ph > or = 11) conditions and subjected to direct fluorescence measurement in the organic solvent ...	1998	9448840
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.	1998	11711075
quantification of metabolites in the indole alkaloid pathways of catharanthus roseus: implications for metabolic engineering	in this article, we present a review of the current state of metabolic engineering in catharanthus roseus. a significant amount of research has contributed to characterization of several individual steps in the biosynthetic pathway of medicinally valuable alkaloids. however, knowledge of the regulation of these pathways is still sparse. using hairy root cultures, we studied the responses of alkaloid metabolism to environmental stimulation such as light and elicitation. through precursor feeding ...	1998	10191413
phytohormone regulation of isoperoxidases in catharanthus roseus suspension cultures.	peroxidase (pod) activity was investigated in catharanthus roseus cell suspensions cultured under different hormonal conditions. depletion of 2,4-dichlorophenoxyacetic acid (2,4-d) from the culture medium enhanced pod activity in cells and spent medium. addition of phytohormones, in particular the auxin 2,4-d, reduced pod activity in medium and cellular compartments and enhanced ionically cell-wall bound pod. the differential modulation of pod is due to hormone effects on synthesis and/or accumu ...	1998	9842727
jasmonate modulates development- and light-regulated alkaloid biosynthesis in catharanthus roseus.	methyl jasmonate, a chemical inducer of secondary metabolism, has been shown to promote vindoline biosynthesis in developing seedlings, as a result of induction of tryptophan decarboxylase (tdc) and desacetylvindoline 4-hydroxylase (d4h). the present studies suggest that jasmonate-based induction of tdc and d4h activities involves modulation of transcriptional, post-transcriptional and post-translational controls. the effects of jasmonate on both enzymes were transient with maximum tdc activity ...	1998	9747537
the iridoid glucoside secologanin is derived from the novel triose phosphate/pyruvate pathway in a catharanthus roseus cell culture.	secologanin is the iridoid building block of the majority of the terpenoid indole alkaloids. in the biosynthesis of secologanin, mevalonate was considered to be the exclusive precursor of isopentenyl diphosphate. after [1-(13)c]glucose feeding to a cell culture of catharanthus roseus, its incorporation into secologanin was studied by 13c nmr spectroscopy. the data showed that the novel triose phosphate/pyruvate and not the mevalonate pathway was the major route for the biosynthesis of secologani ...	1998	9742965