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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
[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
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
sequential solubilization of proteins precipitated with trichloroacetic acid in acetone from cultured catharanthus roseus cells yields 52% more spots after two-dimensional electrophoresis.sample preparation is still the most critical step in two-dimensional gel electrophoresis (2-de), and needs to be optimized for each type of sample. to analyze the proteome of the medicinal plant catharanthus roseus, we developed and evaluated a sequential solubilization procedure for the solubilization of proteins after precipitation in trichloroacetic acid and acetone. the procedure includes solubilization with a conventional urea buffer followed by a stronger solubilizing buffer containing th ...200111922593
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
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
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
terpenoid indole alkaloid production by catharanthus roseus hairy roots induced by agrobacterium tumefaciens harboring rol abc genes.we have established catharanthus roseus hairy root cultures transgenic for the rol abc genes from t(l)-dna of the agropine-type agrobacterium rhizogenes strain a4. the rol abc hairy root lines exhibit a wild-type hairy root syndrome in terms of growth and morphology on solid medium. however, they differ from wild-type hairy root lines in that they more frequently have excellent adaptability to liquid medium and do not appear to form calli during cultivation. moreover, they do not produce detecta ...200616261632
nonradioactive screening method for isolation of disease-specific probes to diagnose plant diseases caused by mycoplasmalike organisms.dna fragments of tomato big bud (bb) mycoplasmalike organism (mlo) in diseased periwinkle plants (catharanthus roseus l.) were cloned to psp6 plasmid vectors and amplified in escherichia coli jm83. a nonradioactive method was developed and used to screen for mlo-specific recombinants. cloned dna probes were prepared by nick translation of the mlo recombinant plasmids by using biotinylated nucleotides. the probes all hybridized with nucleic acid from bb mlo-infected, but not healthy, plants. resu ...199016348195
genetic interrelatedness among clover proliferation mycoplasmalike organisms (mlos) and other mlos investigated by nucleic acid hybridization and restriction fragment length polymorphism analyses.dna was isolated from clover proliferation (cp) mycoplasmalike organism (mlo)-diseased periwinkle plants (catharanthus roseus (l.) g. don.) and cloned into psp6 plasmid vectors. cp mlo-specific recombinant dna clones were biotin labeled and used as probes in dot hybridization and restriction fragment length polymorphism analyses to study the genetic interrelatedness among cp mlo and other mlos, including potato witches'-broom (pwb) mlo. results from dot hybridization analyses indicated that both ...199116348604
effect of salinity and different nitrogen sources on the activity of antioxidant enzymes and indole alkaloid content in catharanthus roseus seedlings.the activities of antioxidant enzymes viz. glutathione reductase, gr; superoxide dismutase, sod; peroxidase, pod; catalase, cat and glutathione-s-transferase, gst and alkaloid accumulation were investigated in leaf pairs (apical, middle, basal) and in roots of catharanthus roseus seedlings under the conditions of different nitrogen sources (20 mm kno(3) and 2 mm nh(4)cl) and salinity, in the absence (non-saline control) and in the presence of 100 mm nacl in the nutrient solution. salinity caused ...200616360799
cyp3a4 and cyp2d6 inhibitory activities of indonesian medicinal plants.thirty samples of indonesian medicinal plants were analyzed for their capacity to inhibit in vitro metabolism by human cytochrome p450 3a4 (cyp3a4) and cyp2d6 with a radiometric assay. the meoh-soluble fractions of 25 samples, prepared from water extracts, demonstrated inhibitory activity more than 50% on the metabolism mediated by cyp3a4, and 21 samples on the metabolism mediated by cyp2d6. among the meoh-soluble fractions, piper nigrum leaf showed the highest inhibitory activity against cyp3a4 ...200616360935
effect of colchicine and catharanthus roseus (vinca rosea) alkaloids on mitosis of syrian hamster bone marrow cells. 196514300954
diacylglycerol kinase from suspension cultured plant cells : purification and properties.diacylglycerol kinase (atp:1,2-diacylglycerol 3-phosphotransferase, ec 2.7.1.107) from suspension-cultured catharanthus roseus cells was extracted from a membrane fraction with 0.6% triton x-100 and 150 millimolar nacl and was purified about 900-fold by deae-cellulose, blue sepharose, gel permeation, and phenyl-sepharose chromatography. the enzyme is obviously membrane bound as activity in the cytosol could not be detected. in the presence of detergents such as triton x-100 (3-[3-cholamidopropyl ...198916666963
immunological detection and quantitation of tryptophan decarboxylase in developing catharanthus roseus seedlings.l-tryptophan decarboxylase (tdc) (ec 4.2.1.27) enzyme activity was induced in cell suspension cultures of catharanthus roseus after treatment with a pythium aphanidermatum elicitor preparation. the enzyme was extracted from lyophilized cells containing high levels of tdc and the protein was purified to homogeneity. the pure protein was used to produce highly specific polyclonal antibodies, and an enzyme-linked immunosorbent assay (elisa) was developed to quantitate the level of tdc antigen durin ...198916667047
high levels of tryptamine accumulation in transgenic tobacco expressing tryptophan decarboxylase.a full-length complementary dna clone encoding tryptophan decarboxylase (tdc; ec 4.1.1.28) from catharanthus roseus (de luca v, marineau c, brisson n [1989] proc natl acad sci usa 86: 2582-2586) driven by the camv 35s promoter was introduced into tobacco (nicotiana tabacum) to direct the synthesis of the protoalkaloid tryptamine from endogenous tryptophan. young, fully expanded leaves of camv 35s-tdc transformed plants had from four to 45 times greater tdc activity than did controls. tryptamine ...199016667846
model plants for studying the interaction between methylobacterium mesophilicum and xylella fastidiosa.over the last few years, endophytic bacterial communities associated with citrus have been studied as key components interacting with xylella fastidiosa. in this study, we investigated the possible interaction between the citrus endophyte methylobacterium mesophilicum sr1.6/6 and x. fastidiosa in model plants such as catharanthus roseus (madagaskar periwinkle) and nicotiana clevelandii (clevelands tobacco). the aim of this study was to establish the fate of m. mesophilicum sr1.6/6 after inoculat ...200616699566
metabolic engineering of cell cultures versus whole plant complexity in production of bioactive monoterpene indole alkaloids: recent progress related to old dilemma.monoterpene indole alkaloids (mias) are a large class of plant alkaloids with significant pharmacological interest. the sustained production of mias at high yields is an important goal in biotechnology. intensive effort has been expended toward the isolation, cloning, characterization and transgenic modulation of genes involved in mia biosynthesis and in the control of the expression of these biosynthesis-related genes. at the same time, considerable progress has been made in the detailed descri ...200616716935
cloning, characterization and localization of three novel class iii peroxidases in lignifying xylem of norway spruce (picea abies).plant class iii peroxidases (poxs) take part in the formation of lignin and maturation of plant cell walls. however, only a few examples of such peroxidases from gymnosperm tree species with highly lignified xylem tracheids have been implicated so far. we report here cdna cloning of three xylem-expressed class iii peroxidase encoding genes from norway spruce (picea abies). the translated proteins, px1, px2 and px3, contain the conserved amino acids required for heme-binding and peroxidase cataly ...200616897487
preparation of mixed alginate elicitors with high activity for the efficient production of 5'-phosphodiesterase by catharanthus roseus cells.when various autoclaved microbial cells suspensions (exogenous elicitors) were added to catharanthus roseus cell cultures, its growth was inhibited but 5'-phosphodiesterase (pdase) production was stimulated. the greatest effect was with autoclaved alteromonas macleodii: the dry cell concentration decreased from 13 to 10.9 mg/ml while pdase production increased from 0.022 to 0.235 u/ml. a combination of a. macleodii (as exogenous elicitor) and 0.1%(w/v) alginate oligomers (ao: acting as both endo ...200616937247
plasmid psci6 from spiroplasma citri gii-3 confers insect transmissibility to the non-transmissible strain s. citri 44.the insect-transmissible strain gii-3 of spiroplasma citri contains plasmids psci1-6, five of which (psci1-5) encode adhesin-like proteins and one (psci6) encodes protein p32, which has been associated with insect transmissibility. in contrast, s. citri strains asp-1 and 44, which cannot be transmitted via injection into the leafhopper vector circulifer haematoceps, lack these proteins and also do not carry plasmids psci1-6. to further study the apparent relationship between the presence of plas ...200616946265
development of a quantitative method for determination of the optimal conditions for protoplast isolation from cultured plant cells.an index [kv: average isolation rate of viable protoplast (number/ml min)] was established to evaluate the optimal conditions for protoplast isolation from cultured plant cells. the optimal conditions for protoplasts isolation from nicotiana tabacum by2 cultured cells could be determined on the basis of the kv [31.7 x 10(3) (number/ml min)]. the colony-forming efficiency of the protoplasts was about 46%. the optimal conditions for protoplasts isolation from catharanthus roseus [kv = 38.1 x 10(3) ...200616955360
ethnomedicines used in trinidad and tobago for urinary problems and diabetes mellitus.this paper is based on ethnobotanical interviews conducted from 1996-2000 in trinidad and tobago with thirty male and female respondents.200617040567
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
catharanthus roseus flower extract has wound-healing activity in sprague dawley rats.catharanthus roseus l (c. roseus) has been used to treat a wide assortment of diseases including diabetes. the objective of our study was to evaluate the antimicrobial and wound healing activity of the flower extract of catharanthus in rats.200617184528
analysis of several iridoid and indole precursors of terpenoid indole alkaloids with a single hplc run.an isocratic hplc system is described which allows the separation of the iridoid and indole precursors of terpenoid indole alkaloids, which are present in a single crude extract. the system consists of a column of lichrospher 60 rp select b 5 microm, 250 x 4 mm (merck) with an eluent of 1% formic acid-acetonitrile-trichloroacetic acid (100:10:0.25, v:v:w) at a flow of 1.2 ml/min. in the suspension cultures of catharanthus roseus secologanin and tryptophan were detected. in the cultures of tabern ...199617252445
quantitative determination of vinblastine in tissue cultures of catharanthus roseus by radioimmunoassay.a radioimmunoassay has been developed for the quantitative determination of small amounts of vinblastine in tissue cultures of catharanthus roseus (l.) g. don. antibody was obtained by the immunization of rabbits against a conjugate of vinblastine with bovine serum albumin. the antibody had a high affinity (ka = 1.2 x 10 (9)l/mol) and specificity for vinblastine. the usable range of standard curve for assay was 0.5-10 ng/ml. crude alkaloid extracts of tissue cultures could be assayed and many sa ...198917262413
homogeneous strictosidine synthase isoenzymes from cell suspension cultures of catharanthus roseus.four separable isoforms of strictosidine synthase, which catalyze condensation of tryptamine with secologanin to form strictosidine, were purified to homogeneity from cultured cells of catharanthus roseus and from leaves of c. roseus plants. these enzymes are distinguished by their isoelectric points as well as by their catalytic properties. the specific activity of the main form (isoform iii) is 104 nkat/mg, k (cat) = 3.2 s (-1). the relative molecular mass is 31 kda as estimated by gel filtrat ...198917262473
resistance to pythium aphanidermatum in diploids and induced autotetraploids of catharanthus roseus.resistance to pythium aphanidermatum (which causes die-back and collar and root rot) in seven diploid and four induced autotetraploid lines of catharanthus roseus was studied in the field during 1983 to 1985. the tetraploid lines were, depending on the year of evaluation, about 13 to 155, 18 to 218, and 17 to 366 times more resistant than diploid lines, when resistance was measured in terms of plant mortality, infection rate, and area under disease curve, respectively. on an average over three y ...198817265286
cloning, characterization and localization of a novel basic peroxidase gene from catharanthus roseus.catharanthus roseus (l.) g. don produces a number of biologically active terpenoid indole alkaloids via a complex terpenoid indole alkaloid biosynthetic pathway. the final dimerization step of this pathway, leading to the synthesis of a dimeric alkaloid, vinblastine, was demonstrated to be catalyzed by a basic peroxidase. however, reports of the gene encoding this enzyme are scarce for c. roseus. we report here for the first time the cloning, characterization and localization of a novel basic pe ...200717298442
promoter analysis of the catharanthus roseus geraniol 10-hydroxylase gene involved in terpenoid indole alkaloid biosynthesis.geraniol 10-hydroxylase (g10h) is an important enzyme in the biosynthetic pathway of monoterpenoid alkaloids found in diverse plant species. the catharanthus roseus g10h controls the first committed step in biosynthesis of terpenoid indole alkaloids (tia). the c. roseus g10h promoter sequence was isolated by a pcr-based genome walking method. sequence analysis revealed that the g10h promoter contains several potential eukaryotic regulatory elements involved in regulation of gene expression. the ...200717321612
effect of indole-3-butyric acid on phytoplasmas in infected catharanthus roseus shoots grown in vitro.phytoplasmas are noncultivable bacteria usually maintained in catharanthus roseus shoots grown in vitro on ms medium with benzylaminopurine. the aim of our research was to examine the influence of indole-3-butyric acid (iba) on c. roseus shoots infected with three different phytoplasma strains. supplement of iba in the medium supported plant growth, photosynthesis and remission of symptoms in all phytoplasma-infected shoots, but had no effect on the presence of ey-c and sa-i phytoplasma strains ...200717328744
evaluation of endophytic colonization of citrus sinensis and catharanthus roseus seedlings by endophytic bacteria.over the last few years, the endophytic bacterial community associated with citrus has been studied as an important component interacting with xylella fastidiosa, the causal agent of citrus variegated chlorosis (cvc). this bacterium may also colonize some model plants, such as catharanthus roseus and nicotiana clevelandii. in the present study, we compared the endophytic colonization of citrus sinensis and catharanthus roseus using the endophytic bacteria klebsiella pneumoniae. we chose an appro ...200717342049
ethnomedicines used in trinidad and tobago for reproductive problems.throughout history women have tried to control or enhance their fertility using herbal remedies, with various levels of societal support. caribbean folk medicine has been influenced by european folk medicine, either through the early spanish and french settlers or through the continuous immigration of spanish-speaking peoples from venezuela. some folk uses are ancient and were documented by galen and pliny the elder.200717362507
enhancing terpenoid indole alkaloid production by inducible expression of mammalian bax in catharanthus roseus cells.bax, a mammalian pro-apoptotic member of the bcl-2 family, triggers hypersensitive reactions when expressed in plants. to investigate the effects of bax on the biosynthesis of clinically important natural products in plant cells, we generate transgenic catharanthus roseus cells overexpressing a mouse bax protein under the beta-estradiol-inducible promoter. the expression of bax in transgenic catharanthus roseus cells is highly dependent on beta-estradiol concentrations applied. contents of catha ...200717447031
identification of a bipartite jasmonate-responsive promoter element in the catharanthus roseus orca3 transcription factor gene that interacts specifically with at-hook dna-binding proteins.jasmonates are plant signaling molecules that play key roles in defense against certain pathogens and insects, among others, by controlling the biosynthesis of protective secondary metabolites. in catharanthus roseus, the apetala2-domain transcription factor orca3 is involved in the jasmonate-responsive activation of terpenoid indole alkaloid biosynthetic genes. orca3 gene expression is itself induced by jasmonate. by loss- and gain-of-function experiments, we located a 74-bp region within the o ...200717496112
a single amino acid in the pspg-box plays an important role in the catalytic function of caugt2 (curcumin glucosyltransferase), a group d family 1 glucosyltransferase from catharanthus roseus.curcumin glucosyltransferase (caugt2) isolated from cell cultures of catharanthus roseus exhibits unique substrate specificity. to identify amino acids involved in substrate recognition and catalytic activity of caugt2, a combination of domain swapping and site-directed mutagenesis was carried out. exchange of the pspg-box of caugt2 with that of ntgt1b (a phenolic glucosyltransferase from tobacco) led to complete loss of enzyme activity in the resulting recombinant protein. however, replacement ...200717509574
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
antioxidant potentials and ajmalicine accumulation in catharanthus roseus after treatment with giberellic acid.changes in antioxidant potentials and indole alkaloid, ajmalicine, production were studied in catharanthus roseus (l.) g. don. plants under treatment with gibberellic acid (ga(3)). the ga(3) treatments were given in two ways, foliar spray and soil drenching methods on 30, 45, 60 and 75 days after planting (dap). the plants were uprooted randomly on 90 dap and separated into root, stem and leaves and used for analyses. the antioxidant potential was studied in terms of non-enzymatc antioxidant mol ...200717643272
pseudomonas fluorescens enhances biomass yield and ajmalicine production in catharanthus roseus under water deficit stress.the effect of plant growth promoting rhizobacteria (pgpr) like pseudomonas fluorescens on growth parameters and the production of ajmalicine were investigated in catharanthus roseus under drought stress. the plants under pot culture were subjected to 10, 15 and 20 days interval drought (did) stress and drought stress with pseudomonas fluorescens at 1mgl(-1) and 1mgl(-1)pseudomonas fluorescens alone from 30 days after planting (dap) and regular irrigation was kept as control. the plants were upro ...200717681765
evaluation of wound-healing potential of catharanthus roseus leaf extract in rats.rats treated with 100 mg /kg/day of the catharanthus roseus ethanol extract had high rate of wound contraction significantly decreased epithelization period, significant increase in dry weight and hydroxyproline content of the granulation tissue when compared with the controls. wound contraction together with increased tensile strength and hydroxyproline content support the use of c. roseus in the management of wound healing.200717683880
hypoglycemic effect of catharanthus roseus in normal and streptozotocin-induced diabetic rats.the effects of crude juice (at 0.5 and 1 ml/kg b.w.) and aqueous extract (at 0.30 and 0.45 gm/kg b.w.) of leaves of catharanthus roseus on serum glucose level in streptozotocin induced diabetic rats were examined at 8 hours, 12 hours and 24 hours following single oral administration. the administration of crude juice at 1 ml/kg b.w. continued for another 9 doses (total 10 single morning doses given) and its effect was examined on the 4th and 11th day. the rats were made diabetic by single intrap ...200717703149
characterization of an ethanol-inducible promoter system in catharanthus roseus hairy roots.efforts to engineer catharanthus roseus hairy roots to produce commercially significant amounts of valuable compounds, such as the terpenoid indole alkaloids vinblastine and vincristine, require the development of tools to study the effects of overexpressing key metabolic and regulatory genes. the use of inducible promoters allows researchers to control the timing and level of expression of genes of interest. in addition, use of inducible promoters allows researchers to use a single transgenic l ...200717715939
calcium chloride effects on salinity-induced oxidative stress, proline metabolism and indole alkaloid accumulation in catharanthus roseus.catharanthus roseus (l.) g. don. plants were grown with nacl and cacl2 in order to study the effect of cacl2 on nacl-induced oxidative stress in terms of lipid peroxidation (tbars content), h2o2 content, osmolyte concentration, proline (pro)-metabolizing enzymes, antioxidant enzyme activities, and indole alkaloid accumulation. the plants were treated with solutions of 80 mm nacl, 80 mm nacl with 5 mm cacl2 and 5 mm cacl2 alone. groundwater was used for irrigation of control plants. plants were u ...200717720584
involvement of nitric oxide signaling in mammalian bax-induced terpenoid indole alkaloid production of catharanthus roseus cells.bax, a mammalian pro-apoptotic member of the bcl-2 family, has been demonstrated to be a potential regulatory factor for plant secondary metabolite biosynthesis recently. to investigate the molecular mechanism of bax-induced secondary metabolite biosynthesis, we determined the contents of nitric oxide (no) of the transgenic catharanthus roseus cells overexpressing a mouse bax protein and checked the effects of no specific scavenger 2,4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide ...200717914641
biotransformation of (+)- and (-)-camphorquinones by plant cultured cells.biotransformation of (+)- and (-)-camphorquinones with suspension plant cultured cells of nicotiana tabacum and catharanthus roseus was investigated. it was found that the plant cultured cells of n. tabacum and c. roseus reduce stereoselectively the carbonyl group of (+)- and (-)-camphorquinones to the corresponding alpha-keto alcohols.200111397432
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
molecular analysis and heterologous expression of an inducible cytochrome p-450 protein from periwinkle (catharanthus roseus l.).we screened cdna libraries from periwinkle (catharanthus roseus) cell cultures induced for indole alkaloid synthesis and selected clones for induced cytochrome p-450 (p-450) proteins by differential hybridization, size of the hybridizing mrna, and presence of amino acid motifs conserved in many p-450 families. four cdnas satisfying these criteria were analyzed in detail. they were grouped in two classes (pcros1, pcros2) that represented two closely related genes of a new p-450 family designated ...199216653087
studies on rhizosphere microbial diversity of some commercially important medicinal plants.a preliminary study was made on four medicinal plants viz., ocimum sanctum l., coleus forskholii briq, catharanthus roseus (l.) g. don. and aloe vera in order to identify and enumerate the rhizosphere, non-rhizosphere and diazotrophic microorganisms in soil. the diazotrophic bacterial population studied includes azospirillum, azotobacter and pseudomonas. the rhizosphere bacterial populations were 23.33 x 10(6)g(-1) in o. sanctum followed by c. roseus (20.46 x 10(6)g(-1)), a. vera (18.44 x 10(6)g ...200817951032
the endophyte curtobacterium flaccumfaciens reduces symptoms caused by xylella fastidiosa in catharanthus roseus.citrus variegated chlorosis (cvc) is a disease of the sweet orange [citrus sinensis (l.)], which is caused by xylella fastidiosa subsp. pauca, a phytopathogenic bacterium that has been shown to infect all sweet orange cultivars. sweet orange trees have been occasionally observed to be infected by xylella fastidiosa without evidencing severe disease symptoms, whereas other trees in the same grove may exhibit severe disease symptoms. the principal endophytic bacterial species isolated from such cv ...200717978797
antioxidant potential and indole alkaloid profile variations with water deficits along different parts of two varieties of catharanthus roseus.the variations in antioxidant potentials and indole alkaloid content were studied in the present investigation, in two varieties (rosea and alba) of catharanthus roseus, an important herb used in traditional as well as modern medicine, exposed to water deficit stress. the antioxidant and alkaloid profiles were estimated from root, stem, leaf, flowers and pods. the antioxidant potentials were examined in terms of non-enzymatic antioxidant molecules and activities of antioxidant enzymes. the non-e ...200818068339
biotransformation of valdecoxib by plant cell cultures.valdecoxib is a new anti-inflammatory drug that is highly selective for inhibition of the inducible form of cyclooxygenase (cox-2). in the present study, biotransformation of valdecoxib was investigated in cell cultures of five medicinal plants, viz., catharanthus roseus, azadirachta indica, capsicum annuum, ervatamia heyneana, and nicotiana tabacum. identification of the biotransformed products was carried out by using high-performance liquid chromatography coupled with diode array detection an ...200818556810
studies on the optimization of growth and indole alkaloid production by hairy root cultures of catharanthus roseus.catharanthus roseus hairy root cultures, genetically transformed with agrobacterium rhizogenes, produce a wide variety of indole alkaloids. the effect of sucrose, phosphate, nitrate, and ammonia concentrations on growth and indole alkaloid production of c. roseus hairy root cultures were studied by using statistical experimental designs and linear regression analysis. contradictory effects of these nutrients on growth and indole alkaloid production were found. the maximal growth was obtained by ...199118600658
kinetics and stoichiometry of growth of plant cell cultures of catharanthus roseus and nicotiana tabacum in batch and continuous fermentors.plant cell suspension cultures of catharanthus roseus and nicotiana tabacum were grown in stirred tank bioreactors operated in batch and continuous mode. the stoichiometry of growth of both species in steady-state glucose limited chemostats was studied at a range of different dilution rates. a linear relation was applied to describe specific glucose uptake, oxygen consumption, and carbon dioxide production as a function of the growth rate. specific respiration deviated greatly from the linear re ...199218601193
production of indole alkaloids by selected hairy root lines of catharanthus roseus.hairy root cultures of catharanthus roseus were established by infection of seedlings with agrobacterium rhizogenes 15834. approximately 150 transformants from four different. c. roseus cultivars were screened for desirable traits in growth and indole alkaloid production. five hairy root clones grew well in liquid culture with doubling times similar to those reported for cell suspensions. fast growing clones had similar morphologies, characterized by thin, straight, and regular branches with thi ...199318609590
seasonal population dynamics of draeculacephala minerva (hemiptera: cicadellidae) and transmission of xylella fastidiosa.the grass sharpshooter, draeculacephala minerva ball (hemiptera: cicadellidae), is a very common and often abundant grass-feeding leafhopper in california. its population dynamics and ability to transmit xylella fastidiosa were monitored over a 2-yr period in california's san joaquin valley. collections of individuals from natural populations in irrigated pastures and alfalfa, medicago savita l. fields adjacent to x. fastidiosa-infected almond (prunus spp.) orchards indicated the occurrence of t ...200818767716
alterations in seedling vigour and antioxidant enzyme activities in catharanthus roseus under seed priming with native diazotrophs.an experiment was conducted on catharanthus roseus to study the effect of seed treatments with native diazotrophs on its seedling growth and antioxidant enzyme activities. the treatments had significant influence on various seedling parameters. there is no significant influence on dry matter production with the diazotrophs, azospirillum and azotobacter. however, the vital seedling parameters such as germination percentage and vigour index were improved. azotobacter treatment influenced maximum o ...200717610323
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 ...200118943446
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 ...199918944803
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 ...199818944838
auxin-treatment induces recovery of phytoplasma-infected periwinkle.to test the effect of auxin-treatment on plant pathogenic phytoplasmas and phytoplasma-infected host.200819120631
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
biosynthesis of salicylic acid in fungus elicited catharanthus roseus cells.feeding experiments using [1-(13)c]-d-glucose to catharanthus roseus (l.) g.don cell suspension cultures followed by elicitation with pythium aphanidermatum extract were performed in order to study the salicylic acid (sa) biosynthetic pathway and that of 2,3-dihydroxybenzoic acid (2,3-dhba) as a comparison. a strongly labeled c-7 and a symmetrical partitioning of the label between c-2 and c-6 would occur if sa was synthesized from phenylalanine. in case of the isochorismate pathway, a relatively ...200919251288
tests for transmission of prunus necrotic ringspot and two nepoviruses by criconemella xenoplax.in two of three trials, detectable color reactions in elisa for prunus necrotic ringspot virus (pnrsv) were observed for criconemella xenoplax handpicked from the root zone of infected peach trees. criconemella xenoplax (500/pot) handpicked from root zones of peach trees infected with pnrsv failed to transmit the virus to cucumber or peach seedlings. the nematode also failed to transmit tomato ringspot (tomrsv) or tobacco ringspot viruses between cucumbers, although xiphinema americanum transmit ...199019287748
improved accumulation of ajmalicine and tetrahydroalstonine in catharanthus cells expressing an abc transporter.the biosynthetic pathway of monoterpenoid indole alkaloids in catharanthus roseus is located throughout various membranes at both the cellular and intercellular levels. atp-binding cassette (abc) transporters are known to export vincristine and vinblastine from human cancer cells. it has recently been shown that abc transporters are also involved in the transport of various monoterpenoid alkaloids in catharanthus roseus cells. over-expression of an abc transporter in this plant might therefore a ...200919403195
bioreactor production of secondary metabolites from cell cultures of periwinkle and sandalwood.a bench-top bioreactor allowing continuous extraction of secondary metabolites is designed for catharanthus roseus l. (g.) don (periwinkle) and santalum album l. (sandalwood) plant cell suspensions. periwinkle cell cultures are exposed to biotic elicitors (aspergillus niger, crude chitin) and abiotic elicitors (mannitol, methyl jasmonate) to induce alkaloid production. whereas most of the biotic elicitors are effective when added on day 15 of culture, the abiotic elicitors are effective when add ...200919521856
increased vincristine production from agrobacterium tumefaciens c58 induced shooty teratomas of catharanthus roseus g. don.dimeric indole alkaloids are used extensively for cancer therapy. agrobacterium tumefaciens c58 strain was used for induction of shooty teratoma in catharanthus roseus using epicotyl and stem node explants. the transformed nature of shooty teratomas was confirmed by nopaline assay. growth kinetics of shooty teratomas depicted maximum growth during 21-24 days of culture. dimeric alkaloid vincristine in the transformed cultures was present at a concentration of 0.011 that was tenfold higher compar ...200919521912
overexpression of the hmg-coa reductase gene leads to enhanced artemisinin biosynthesis in transgenic artemisia annua plants.an effective and affordable treatment against malaria is still a challenge for medicine. most contemporary drugs either are too expensive to produce or are not effective against resistant strains of the malaria parasite plasmodium falciparum. the plant artemisia annua l. is the source of artemisinin, an effective drug against malaria for which no resistant strains of the bacterium have been reported. however, the artemisinin content of a. annua is very low, which makes its production expensive. ...200919551613
comparison of hypotensive and hypolipidemic effects of catharanthus roseus leaves extract with atenolol on adrenaline induced hypertensive rats.the leaves extract of catharanthus roseus was investigated for hypotensive and hypolipidemic effects in adrenaline-induced hypertensive rats (aihr) and compared with those of atenolol in a crossover design. the pharmacologically active components responsible for hypotensive activities were isolated from plant using bioassay guided purification approach and the structure of the compounds was proposed by spectroscopic methods. catharanthus roseus leaves extract and commercial drug atenolol were ad ...200919553172
transmission of different isolates of spiroplasma citri to carrot and citrus by circulifer tenellus (hemiptera: cicadellidae).carrot purple leaf disease was first reported in 2006 in the state of washington and was associated with spiroplasma citri. the disease also was reported in california in 2008. the objectives of this work were to fulfill koch's postulates and to determine 1) whether the beet leafhopper, circulifer tenellus (baker) (hemiptera: cicadellidae), transmits carrot [daucus carota l. subsp. sativus (hoffm.) arcang] isolates of s. citri; and 2) whether carrot and citrus [citrus sinensis (l.) osb.]-derived ...200919736751
response of mycorrhizal periwinkle plants to aster yellows phytoplasma infection.the objective of our research was to assess if arbuscular mycorrhizal (am) fungal colonization can modify the effect of infection by two aster yellows phytoplasma strains (ay1, aysim) in catharanthus roseus plants. both phytoplasma strains had a negative effect on the root fresh weight, but they differed in symptoms appearance and in their influence on photosynthetic and transpiration rates of the periwinkle plants. am plants showed significantly reduced shoot fresh weight, while the transpirati ...201019756778
transmission of methylobacterium mesophilicum by bucephalogonia xanthophis for paratransgenic control strategy of citrus variegated chlorosis.methylobacterium mesophilicum, originally isolated as an endophytic bacterium from citrus plants, was genetically transformed to express green fluorescent protein (gfp). the gfp-labeled strain of m. mesophilicum was inoculated into catharanthus roseus (model plant) seedlings and further observed colonizing its xylem vessels. the transmission of this endophyte by bucephalogonia xanthophis, one of the insect vectors that transmit xylella fastidiosa subsp. pauca, was verified by insects feeding fro ...200919763419
screening of herbal extracts for activation of the human peroxisome proliferator-activated receptor.the peroxisome proliferator-activated receptors play a pivotal role in metazoan lipid and glucose homeostasis. synthetic activators of pparalpha (fibrates) and ppargamma (glitazones) are therefore widely used for treatment of dislipidemia and diabetes, respectively. there is growing evidence for herbal compounds to influence nuclear receptor signalling e.g. the ppars. we recently reported carnosic acid and carnosol, both being diterpenes found in the labiate herbs sage and rosemary, to be activa ...200617152989
characterization of the phenylalanine ammonia-lyase gene (slpal5) from tomato (solanum lycopersicum l.).phylogenetic analysis based on the deduced amino acid sequence of phenylalanine ammonia-lyase gene (slpal5) cdna from tomato (solanum lycopersicum l.) revealed high sequence similarity to pal genes in nicotiana tabacum (92%), ipomoea nil (87%), manihot esculenta (84%), and catharanthus roseus (84%). the slpal5 gene exists as multiple copies in the tomato plant, and its transcription was strongly expressed in old leaves and flowers. from 5 days post-anthesis to the onset of ripening, slpal5 expre ...200918791854
gene expression profiling of phytoplasma-infected madagascar periwinkle leaves using differential display.phytoplasmas are small (0.2-0.8 μm), wall-less, pleiomorphic prokaryotes responsible of numerous economically important plant diseases. they are characterized by a very small genome and are obligate parasites of phloem tissues and some insects that act as vectors of infection. to investigate molecular mechanisms involved in pathogenesis, the differential display technique was here applied to identify plant genes whose transcription was significantly altered in leaves of madagascar periwinkle (ca ...201120127177
screening molecules for control of citrus huanglongbing using an optimized regeneration system for 'candidatus liberibacter asiaticus'-infected periwinkle (catharanthus roseus) cuttings.citrus huanglongbing is one of the most destructive diseases of citrus worldwide. the disease is associated with three different species of 'candidatus liberibacter', of which 'ca. l. asiaticus' is the most widely distributed. an optimized system using 'ca. l. asiaticus'-infected periwinkle cuttings was developed to screen chemical compounds effective for controlling the bacterial population while simultaneously assessing their phytotoxicity. the optimal regeneration conditions were determined t ...201020128697
effects of hydrostatic pressure, agitation and co2 stress on phytophthora nicotianae zoospore survival.phytophthora nicotianae breda de haan is a common pathogen of ornamental plants in recycled irrigation systems. in a previous study, annual vinca (catharanthus roseus don) inoculated with zoospore suspensions using a co(2)-pressurized sprayer had less foliage blight than plants inoculated using a hand sprayer. here, the impact of hydrostatic pressure, agitation and aeration with co(2) on the survival of p. nicotianae zoospores was examined.201020201053
influence of cellular differentiation and elicitation on intermediate and late steps of terpenoid indole alkaloid biosynthesis in catharanthus roseus.the invaluable antineoplastic bisindole alkaloids of catharanthus roseus and their precursor, vindoline, are not produced in cell cultures. the intricacies involved in endogenous (cellular differentiation) and exogenous (elicitation) regulation of their biosynthesis need to be dissected out for favorable exploitation. this study aimed at elucidating the effect of pythium aphanidermatum homogenate and methyl jasmonate (meja) on in vitro cultures (of cv. 'dhawal') representing increasing level of ...201020217156
increasing anthraquinone production by overexpression of 1-deoxy-d: -xylulose-5-phosphate synthase in transgenic cell suspension cultures of morinda citrifolia.a morinda citrifolia cell line was obtained by overexpresion of 1-deoxy-d: -xylulose 5-phosphate synthase (dxs) from catharanthus roseus, a key enzyme of the metabolic pathway of anthraquinones (aqs). this cell line increased aqs production by about 24% compared to the control cell line. this transgenic cell line which carries dxs cdna isolated from catharanthus roseus, was achieved by direct transformation of cell suspension cultures of m. citrifolia using a hypervirulent agrobacterium tumefaci ...201020349334
biotransformation of artemisinin using cell suspension cultures of catharanthus roseus (l.) g.don and lavandula officinalis l.artemisinin, an antimalarial compound, at 5 mg/40 ml, was transformed by cell suspension cultures of catharanthus roseus (l.) g.don and lavandula officinalis l. into deoxyartemisinin with yields >78% (3.93 mg deoxyartemisinin from 5 mg artemisinin). maximum conversion (78.6 and 78%) occurred after 6 and 7 days of adding artemisinin to 20 and 9 days old cultures of c. roseus and l. officinalis, respectively. the procedure was scaled up by and 500 mg artemisinin was transformed into 390 mg deoxyar ...201020369274
zoospore density-dependent behaviors of phytophthora nicotianae are autoregulated by extracellular products.phytophthora species are destructive fungus-like plant pathogens that use asexual single-celled flagellate zoospores for dispersal and plant infection. many of the zoospore behaviors are density-dependent although the underlying mechanisms are poorly understood. here, we use p. nicotianae as a model and demonstrate autoregulation of some zoospore behaviors using signal molecules that zoospores release into the environment. specifically, zoospore aggregation, plant targeting, and infection requir ...201020528180
overexpression of g10h and orca3 in the hairy roots of catharanthus roseus improves catharanthine production.a number of genes that function in the terpenoid indole alkaloids (tias) biosynthesis pathway have been identified in catharanthus roseus. except for the geraniol 10-hydroxylase (g10h) gene, which encodes a cytochrome p450 monooxygenase, several of these genes are up-regulated by orca3, a jasmonate-responsive apetala2 (ap2)-domain transcript factor. in this study, the g10h gene was transformed independently, or co-transformed with orca3 into c. roseus, using agrobacterium rhizogenes msu440. hair ...201020535474
effect of loss of t-dna genes on mia biosynthetic pathway gene regulation and alkaloid accumulation in catharanthus roseus hairy roots.hairy roots are generated by integration of t-dna in host plant genome from root inducing (ri) plasmid of agrobacterium rhizogenes and have been utilized for production of secondary metabolites in different plant systems. in catharanthus roseus, hairy roots are known to show different morphologies, growth patterns, and alkaloid contents. it is also known that during transformation, there is a differential loss of a few t-dna genes. to decipher the effect of loss of t-dna genes on the various asp ...201020625736
vinca drug components accumulate exclusively in leaf exudates of madagascar periwinkle.the monoterpenoid indole alkaloids (mias) of madagascar periwinkle (catharanthus roseus) continue to be the most important source of natural drugs in chemotherapy treatments for a range of human cancers. these anticancer drugs are derived from the coupling of catharanthine and vindoline to yield powerful dimeric mias that prevent cell division. however the precise mechanisms for their assembly within plants remain obscure. here we report that the complex development-, environment-, organ-, and c ...201020696903
a phytoplasma related to 'candidatus phytoplasma asteri' detected in citrus showing huanglongbing (yellow shoot disease) symptoms in guangdong, p. r. china.citrus huanglongbing (hlb) or yellow shoot disease (i.e., greening disease) is highly destructive to citrus production worldwide. understanding the etiology of hlb is critical for managing the disease. hlb is currently associated with infection by 'candidatus liberibacter spp.' around the world, including china. however, koch's postulates have not been fulfilled. in addition, other plant pathogens also may be involved in hlb. in a survey performed in guangdong province, p. r. china in 2006 and 2 ...200919203275
biochemical and epigenetic changes in phytoplasma-recovered periwinkle after indole-3-butyric acid treatment.to elucidate the possible mechanism of phytoplasma elimination from periwinkle shoots caused by indole-3-butyric acid (iba) treatment.201020796083
homolog of tocopherol c methyltransferases catalyzes n methylation in anticancer alkaloid biosynthesis.madagascar periwinkle (catharanthus roseus) is the sole source of the anticancer drugs vinblastine and vincristine, bisindole alkaloids derived from the dimerization of the terpenoid indole alkaloids vindoline and catharanthine. full elucidation of the biosynthetic pathways of these compounds is a prerequisite for metabolic engineering efforts that will improve production of these costly molecules. however, despite the medical and commercial importance of these natural products, the biosynthetic ...201020956330
clustered transcription factor genes regulate nicotine biosynthesis in tobacco.tobacco (nicotiana tabacum) synthesizes nicotine and related pyridine alkaloids in the root, and their synthesis increases upon herbivory on the leaf via a jasmonate-mediated signaling cascade. regulatory nic loci that positively regulate nicotine biosynthesis have been genetically identified, and their mutant alleles have been used to breed low-nicotine tobacco varieties. here, we report that the nic2 locus, originally called locus b, comprises clustered transcription factor genes of an ethylen ...201020959558
efficacy of anthelmintic properties of medicinal plant extracts against haemonchus contortus.the development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. among these alternatives are several medicinal plants traditionally used as anthelmintics. this present work evaluated the efficacy of ethyl acetate, acetone, and methanol dried leaf and seed extracts of five medicinal plants were tested in vitro ovicidal and larvicidal activities on haemonchus contortus. the in vitro assay was based on egg hatch as ...201020980034
spatial organization of the vindoline biosynthetic pathway in catharanthus roseus.vindoline constitutes the main terpenoid indole alkaloid accumulated in leaves of catharanthus roseus, and four genes involved in its biosynthesis have been identified. however, the spatial organization of the tabersonine-to-vindoline biosynthetic pathway is still incomplete. to pursue the characterization of this six-step conversion, we illustrated, with in situ hybridization, that the transcripts of the second biosynthetic enzyme, 16-hydroxytabersonine 16-o-methyltransferase (16omt), are speci ...201021047699
integrating carbon-halogen bond formation into medicinal plant metabolism.halogenation, which was once considered a rare occurrence in nature, has now been observed in many natural product biosynthetic pathways. however, only a small fraction of halogenated compounds have been isolated from terrestrial plants. given the impact that halogenation can have on the biological activity of natural products, we reasoned that the introduction of halides into medicinal plant metabolism would provide the opportunity to rationally bioengineer a broad variety of novel plant produc ...201021048708
zoospore interspecific signaling promotes plant infection by phytophthora.oomycetes attack a huge variety of economically and ecologically important plants. these pathogens release, detect and respond to signal molecules to coordinate their communal behaviors including the infection process. when signal molecules are present at or above threshold level, single zoospores can infect plants. however, at the beginning of a growing season population densities of individual species are likely below those required to reach a quorum and produce threshold levels of signal mole ...201021138563
interactions between 'candidatus phytoplasma mali' and the apple endophyte epicoccum nigrum in catharanthus roseus plants.we investigated the ultrastructural and molecular interactions between 'candidatus phytoplasma mali' and the apple endophyte epicoccum nigrum in the experimental host catharanthus roseus to determine whether inoculation of endophyte could trigger defence reactions in the host.201121205105
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