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growth and embryo formation in wild-carrot suspension cultures with ammonium ion as a sole nitrogen source.wild-carrot (daucus carota l.) suspension cultures grew and produced embryos on ammonium ion as a sole source of nitrogen in the absence of any exogenous kreb's cycle acid when the ph of the medium was controlled by continuous titration with with koh or khco3.197827444
repression of asexual embryogenesis in vitro by some plant growth regulators.a factor that represses asexual embryogenesis has been observed in the rutaceae, with particularly high concentrations in the naturally monoembryonic cultivars. this investigation was an initial step towards identifying the factor. citrus reticulata blanco ponkan mandarin nucellus explants and daucus carota l. 'queen anne's lace' callus were employed to examine effects of known plant growth regulators and to determine possible identity of one or more of them with the repressive factor. the chala ...1977145403
the molecular weight of rrna precursor molecules and their processing in higher plant cells.actively dividing callus cells of higher plants (petroselinum crispum, daucus carota, acer pseudoplatanus) were used to detect the primary gene product of rdna in vivo. parsley and carrot cells were labelled with [32p]orthophosphate. under non-denaturing conditions, in both cases only one high molecular weight rrna precursor was present on polyacrylamide gels. its molecular weight did not exceed 2.5 x 10(6) dalton. under denaturing conditions, 2.0--2.1 x 10(6) dalton were determined on formamide ...2003156469
pinwheel inclusions in morphogenesis: a possible alternative to induction by viruses.pinwheel inclusions (pws) were found in cells of callus tissue derived from explants of secondary phloem parenchyma of carrot (daucus carota) storage root and grown on a basal medium containing zeatin and indoleacetic acid or coconut milk, naphthalene acetic acid, or combinations of these. preliminary attempts to demonstrate the presence of viruses in the callus tissue failed. the possibility that the tissles were infected by a low titer or unstable conventional virus or by a defective mutant ha ...1990184764
[metabolism of nicotinic acid in plant cell suspension cultures, iv: occurrence and metabolism of nicotinic acid n-alpha-arabinoside (author's transl)].application of nicotinic acid to cell suspension cultures of petroselinum hortense hoffm., daucus carota, nicotiana tabacum and nicotiana glauca leads to the formation of the recently isolated[2] nicotinic acid n-alpha-l-arabinoside. in these cell cultures the arabinoside is a metabolically active compound; the nicotinic acid moiety is used for nad synthesis and nicotinic acid degradation involving decarboxylation and ring fission. n-methylnicotinic acid (trigonelline) and nicotinic acid n-alpha ...1976185135
expression of aspartokinase, dihydrodipicolinic acid synthase and homoserine dehydrogenase during growth of carrot cell suspension cultures on lysine- and threonine-supplemented media.reduction in the amounts of activity of the first enzyme, aspartokinase (ec 2.7.2.4) and two branch-point enzymes, dihydrodipicolinic acid synthase (ec 4.2.1.52) and homoserine dehydrogenase (ec 1.1.1.3), located in the pathway for the synthesis of aspartate-family amino acids, occurred when cell suspension cultures of daucus carota l. var. danvers were grown in media containing 2 mm threonine or 2 mm lysine, endproducts of the pathway. activity of the lysine-sensitive form of aspartokinase was ...1979232596
antispasmodic activity of the tertiary base of daucus carota, linn. seeds.a nitrogen containing base responding to mayer's test and dragendorff's reagent for tertiary bases has been isolated from the seeds of daucus carota linn. the effects of the base as its bromide have been studied on smooth muscles of ileum, uterus, blood vessels and trachea of different species of animals. the tertiary base has been found to have papaverine like nonspecific smooth muscle relaxant and spasmolytic activity, but its activity was found to be about one-tenth of that of papaverine.1979521127
[flavonols and flavones of vegetables. viii. flavones of carrot leaves (author's transl)].the flavonoid constituents of carrot leaves (daucus carota l. ssp. sativa) were separated by means of cellulose column chromatography, and the following compounds were obtained crystalline and identified by usual procedures: luteolin 7-beta-d-glucoside as the main flavon, luteolin 4'-beta-d-glucoside, luteolin 7-beta-d-glucuronide, apigenin 7-beta-d-glucoside, apigenin 7-rutinoside, chrysoeriol 7-beta-d-glucoside. luteolin 7-rutinoside also was identified, but could not be obtained crystalline.1977595898
electron microscopic studies in cultivated plants. ii. fresh and stored roots of daucus carota l.scanning (sem) and transmission (tem) electron microscopic studies in fresh and stored roots (4 months at an average temperature of +8 degrees c) of daucus carota l. (carrots) were carried out. chief stress was laid on the analysis of the histological and cytological structure of the secondary phloem parenchyma cell. sem images show the three-dimensional histological arrangement of the cells. moreover, the outlines of lipid droplets, mitochondria, starch grains, and carotin pigment crystals are ...1978636662
dna, rna and protein content of tissue during growth and embryogenesis in wild-carrot suspension cultures.a highly selected population of cells (clumps from 63 to 125 micron in diameter), obtained by screening 14-day-old stock suspension cultures of wild carrot (daucus carota l.), was used to initiate cultures in this study. time-course changes in dna, rna and protein were followed when these cultures were grown in the presence or absence of 2.25 mum 2,4-dichlorophenoxyacetic acid (2,4-d). the data show that growth of these cultures, particularly in the early part of the growth curve, is different f ...1978669724
rapidly-labelled rna species isolated from cell suspensions of daucus carota. 1977918306
variation of cell cycle duration within suspension cultures of daucus carota and its consequence for the induction of ploidy changes with colchicine. 1976935509
phenylalanine-ammonia-lyase activity and biosynthesis of anthocyanins and chlorogenic acid in tissue cultures of daucus carota (author's transl). 1976981382
estrogenic and pregnancy interceptory effects of carrot daucus carota seeds. 1976992821
the duration of the cell cycle of daucus carota l. in vivo and in vitro. 19751132430
pharmacological studies on daucus carota part i. 19751178783
[the influence of gibberellic acid on the synthesis of anthocyanin in tissue cultures of daucus carota (author's transl)]. 20051187874
[induction of anthocyanin biosynthesis in tissue cultures of daucus carota (author's transl)]. 19751187875
[production of xanthan gum in immobilized cultures of xanthomonas campestris].the efficiency of xanthan production through surface processes was evaluated. the best porous material was selected first. thereafter, a comparative study was performed using submerged agitated process vs other without agitation but containing the selected porous material. the culture medium used was white potatoes infusion, buffered with k2hpo4 and supplemented with glucose in diverse concentrations. besides, to evaluate a different type of surface process, three vegetables were valued: ipomaea ...19921298018
release of carrot plasma membrane-associated phosphatidylinositol kinase by phospholipase a2 and activation by a 70 kda protein.plasma membranes were isolated from carrot (daucus carota l.) cells grown in suspension culture and treated with phospholipase a2 from snake or bee venom for 10 min. as a result of this treatment, phosphatidylinositol kinase activity was recovered in the soluble fraction. there was no detectable diacylglycerol kinase or phosphatidylinositol monophosphate kinase activity released from the membranes after the phospholipase a2 treatment. treating the plasma membranes with phospholipase c or d did n ...19921311960
anthocyanins from cell suspension cultures of daucus carota.six anthocyanins were isolated from cell suspension cultures of an afghan cultivar of daucus carota by pc or hplc. the structures of these compounds were elucidated by spectroscopic methods as cyanidin 3-o-lathyroside, cyanidin 3-o-(2''-o-beta-d-xylopyranosyl-6''-o-beta-d-glucopyranosyl-beta-d- galactopyranoside), and the latter acylated with 4-coumaric, ferulic, 4-hydroxybenzoic or sinapic acid. unusual 1h nmr chemical shifts and 1h noe data indicate an intramolecular copigmentation of the agly ...19921368363
isolation and genetic analysis of an agrobacterium tumefaciens avirulent mutant with a chromosomal mutation produced by transposon mutagenesis.a transposon 5 (tn5) insertion was introduced into the genome of a. tumefaciens (a-208 strain harboring a nopaline type ti-plasmid) using a conjugative pjb4ji plasmid containing tn5. five thousand transconjugants were assayed for virulence on carrot (daucus carota l.) disks; 54 isolates were avirulent or very attenuated. the cellular localization (plasmid or chromosome) of the tn5 insertion in those isolates were identified by southern hybridization analysis. an avirulent mutant (b-90 strain) wi ...19921369092
glyphosate selected amplification of the 5-enolpyruvylshikimate-3-phosphate synthase gene in cultured carrot cells.car and c1, two carrot (daucus carota l.) suspension cultures of different genotypes, were subjected to stepwise selection for tolerance to the herbicide glyphosate [(n-phosphonomethyl)glycine]. the specific activity of the target enzyme, 5-enolpyruvylshikimate-3-phosphate synthase (epsps), as well as the mrna level and copy number of the structural gene increased with each glyphosate selection step. therefore, the tolerance to glyphosate is due to stepwise amplification of the epsps genes. duri ...19921375313
a gene expressed preferentially in the globular stage of somatic embryogenesis encodes elongation-factor 1 alpha in carrot.we have isolated cdna of genes that are preferentially expressed during somatic embryogenesis of carrot (daucus carota l.) by differential screening of globular embryos and cells that are dividing in an unorganized manner. as a result of northern-blot analysis, one of the genes identified in this way, which we refer to as cem1, was found to be expressed at high levels in somatic embryos at the globular and heart-shaped stages. in-situ hybridization using globular embryos revealed that the mrna t ...19921396695
isolation and characterization of a cdna that encodes ecp31, an embryogenic-cell protein from carrot.a full-length cdna for ecp31, an embryogenic cell protein from carrot (daucus carota l.) with a m(r) of 31,000 (kiyosue t, satoh s, kamada h, harada h (1991) plant physiol 95: 1077-1083), was isolated from a cdna library prepared from embryogenic cells using pcr-amplified dna as a probe. the genomic southern blot analysis revealed that there are two or three genes for ecp31 in the carrot genome. the transcripts of ecp31 accumulated in the peripheral regions of clusters of embryogenic cells and d ...19921535801
purification and characterization of a soluble beta-fructofuranosidase from daucus carota.soluble beta-fructofuranosidase with an intracellular location and an isoelectric point of 3.8 (isoenzyme i) was purified and characterized from dry seeds and seedlings of carrot (daucus carota). the enzyme hydrolyzed sucrose with a km of 5 mm and a broad ph optimum around 5.0. the purified protein, which was n-glycosylated with high-mannose-containing and high-xylose-containing complex glycans, eluted as a monomeric polypeptide with a molecular mass of 68,000 from a gel-filtration column. on sd ...19921541302
intermediate filament antigens of 60 and 65 kda in the nuclear matrix of plants: their detection and localization.although the presence of a matrix in plant nuclei has been reported, major questions remain about its structural and biochemical features. we have used an intermediate filament antibody of broad specificity to explore whether daucus carota (carrot) nuclei and nuclear matrices contain intermediate filament/lamin antigens and, if so, where specifically they are localized. sds-page and western blotting revealed two bands, at 60 and 65 kda, that were highly immunoreactive with the intermediate filam ...19921544367
spatial and temporal expression patterns directed by the agrobacterium tumefaciens t-dna gene 5 promoter during somatic embryogenesis in carrot.we have analysed the patterns of expression of a gene encoding beta-glucuronidase (gus) fused to the promoter of the agrobacterium tumefaciens t-dna gene 5 during embryogenesis in carrot, daucus carota l. gene expression was monitored by a histochemical assay of beta-glucuronidase activity. the gene 5 promoter, although of bacterial origin, conferred expression upon the marker gene in all stages of embryo development. the patterns of expression however, differed between embryos in different stag ...19921558941
induced plant responses to pathogen attack. analysis and heterologous expression of the key enzyme in the biosynthesis of phytoalexins in soybean (glycine max l. merr. cv. harosoy 63).in soybean (glycine max l.), pathogen attack induces the formation of glyceollin-type phytoalexins. the biosynthetic key enzyme is a reductase which synthesizes 4,2', 4'-trihydroxychalcone in co-action with chalcone synthase. screening of a soybean cdna library from elicitor-induced rna in lambda gt11 yielded two classes of reductase-specific clones. the deduced proteins match to 100% and 95%, respectively, with 229 amino acids sequenced in the purified plant protein. four clones of class a were ...19911840523
characterization of three agrobacterium tumefaciens avirulent mutants with chromosomal mutations that affect induction of vir genes.three agrobacterium tumefaciens mutants with chromosomal mutations that affect bacterial virulence were isolated by transposon mutagenesis. two of the mutants were avirulent on all hosts tested. the third mutant, ivr-211, was a host range mutant which was avirulent on bryophyllum diagremontiana, nicotiana tabacum, n. debneyi, n. glauca, and daucus carota but was virulent on zinnia elegans and lycopersicon esculentum (tomato). that the mutant phenotype was due to the transposon insertion was dete ...19911846853
proteolytic and partial sequencing studies of the bifunctional dihydrofolate reductase-thymidylate synthase from daucus carota.the bifunctional dihydrofolate reductase-thymidylate synthase (dhfr-ts) of daucus carota has been further characterized as regards molecular weight, amino acid composition, protease digestion and microsequencing of proteolytic peptides. data reported in this paper demonstrate that the carrot protein has a calculated mr of 124,000 thus indicating that, contrarily to what has previously been suggested, it occurs as a dimer of identical subunits. results of partial amino acid microsequencing show t ...19911863769
molecular cloning, induction and taxonomic distribution of caffeoyl-coa 3-o-methyltransferase, an enzyme involved in disease resistance.trans-caffeoyl-coa 3-o-methyltransferase is involved in the reinforcement of the plant cell wall under conditions that trigger the disease resistance response (pakusch, a.-e., kneusel, r.e., and matern, u. (1989) arch. biochem. biophys. 271, 488-494). partial amino acid sequences of the enzyme from cultured parsley cells that had been treated with a crude elicitor were identified (pakusch, a.-e., matern, u., and schiltz, e. (1991) plant physiol. 95, 137-143), and corresponding degenerated oligon ...19911894629
detection and prevalence of listeria monocytogenes in the agricultural ecosystem.the sensitivity of four different enrichment procedures to detect listeria monocytogenes in the presence of high levels of streptococcus faecalis was investigated. defined mixed cultures of strep. faecalis and l. monocytogenes gave better results with one-stage enrichment techniques. for manure samples, however, two-stage enrichment techniques gave the best performance. the so-called cold enrichment techniques were found to be unsatisfactory for samples from natural environments. the following m ...19911955415
selective sensitivity to methylmercury of specific cell aggregates and validity of the "nurse" cell concept.meristematic cells of carrot (daucus carota--ca68-10) were grown in a heterogeneous suspension culture in the absence of (2,4-dichlorophenoxy)acetic acid in 71-v medium in the dark. freshly inoculated cell cultures were treated daily with methyl mercury for the first 4 days and harvested on day 7. the cultures were separated (by selective filtration) into groups of aggregates varying in size from 44 to 900 microns. methyl mercury severely decreased the cell mass of the dominant (300-microns) fra ...19912065632
structure and function of the promoter of the carrot v-type h(+)-atpase catalytic subunit gene.we investigated the 5'-upstream region of the gene encoding the catalytic subunit of the v-type h(+)-atpase in daucus carota. a genomic sublibrary was screened with a cdna probe, and a 4-kilobase genomic clone was obtained covering the first two exons and about 3 kilobases of the 5'-upstream sequence. the intron/exon boundaries matched established consensus sequences. within 240 base pairs (bp) upstream of the initiation codon three putative tata boxes were found. ribonuclease protection and pri ...19902139875
purification and characterization of cytosolic aldolase from carrot storage root.a single fructose-1,6-bisphosphate (fbp) aldolase has been detected in extracts from carrot storage roots (daucus carota l.). the enzyme was purified 850-fold to electrophoretic homogeneity and a final specific activity of 26.3 mumols of fbp utilized/min per mg of protein. sds/page of the final preparation revealed a single protein-staining band of 40 kda. the native molecular mass was determined by analytical gel filtration to be 159 kda, indicating that the enzyme is a homotetramer. denaturing ...19902198022
an actin network is present in the cytoplasm throughout the cell cycle of carrot cells and associates with the dividing nucleus.we have studied the f-actin network in cycling suspension culture cells of carrot (daucus carota l.) using rhodaminyl lysine phallotoxin (rlp). in addition to conventional fixation with formaldehyde, we have used two different nonfixation methods before adding rlp: extracting cells in a stabilizing buffer; inducing transient pores in the plasma membrane with pulses of direct current (electroporation). these alternative methods for introducing rlp revealed additional features of the actin network ...19872440896
a family of abundant plasma membrane-associated glycoproteins related to the arabinogalactan proteins is unique to flowering plants.we have identified a family of abundant peripheral plasma membrane glycoproteins that is unique to flowering plants. they are identified by a monoclonal antibody, mac 207, that recognizes an epitope containing l-arabinose and d-glucuronic acid. immunofluorescence and immunogold labeling studies locate the mac 207 epitope to the outer surface of the plasma membrane both in protoplasts and in intact tissues. in some cells mac 207 also binds to the vacuolar membrane, probably reflecting the movemen ...19892469683
evidence of an auxin-mediated phosphoinositide turnover and an inositol (1,4,5)trisphosphate effect on isolated membranes of daucus carota l.microsomal membranes from carrot suspension cells were phosphorylated in vitro with [gamma-32p]atp. in the presence of submicromolar concentrations of the natural auxin indoleacetic acid (iaa), a rapid, but transient decrease of the [32p] label could be detected in the phospholipid extracts of the membranes. the phytohormone effect was not the result of an inhibition of the lipid phosphorylation reactions, but was caused by a simultaneous release of water-soluble compounds, which, according to t ...19892550489
molecular and genetic analysis of an embryonic gene, dc 8, from daucus carota l.to understand the morphogenetic and physiological processes occurring during plant embryogenesis, we isolated cdna clones homologous to genes preferentially expressed during somatic embryogenesis. one of these cdna clones detected an embryo-specific mrna species with a corresponding protein of 66 kda. the expression pattern of the mrna is similar between somatic and zygotic embryos of carrots. to characterize the gene encoding this mrna, we isolated the corresponding genomic clones. molecular an ...19892571069
a qualitative and quantitative assay of dihydrofolate reductase in carrot cells resistant to methotrexate.the cytochemical pattern and the quantitative assay of dhfr on daucus carota cell lines sensitive and resistant to methotrexate (mtx) are described. cytoplasmatic enzyme activity is evidenced as granules of formazan, final reaction product, in the majority of the cells. dhfr activity appears low in daucus carota cells used as control while in carrot cells resistant to mtx is very high, an observation which parallels previous biochemical studies. these results are supported by quantitative data o ...19892757603
reconstitution of intermediate filaments from a higher plant.immunological studies have shown that plants contain intermediate-filament antigens, but it is not known whether these proteins are capable in themselves of forming filaments. to address this problem, a detergent-resistant and high-salt-insoluble fraction from carrot (daucus carota l.) suspension cells was solubilized with 9 m-urea and then subjected to a two-step dialysis procedure, devised for the reconstitution of animal intermediate filaments. this induced the self-assembly of 10 nm filament ...19892775240
growth effects, uptake and metabolism of trifluralin in tissue cultures.growth effects, uptake and metabolism of trifluralin (alpha, alpha, alpha-trifluoro-2,6-dinitro-n,n-dipropyl-p-toluidine) in carrot (daucus carota l.) and tobacco (nicotiana tabaccum l.) callus tissue were determined. carrot callus was initiated from tap root tissue on murashige and skoog medium with kinetin and 2,4-dichlorophenoxy acetic acid (2,4-d). tobacco callus was initiated from pith tissue on murashige and skoog medium with indole-3-acetic acid (iaa) and kinetin.19892809078
chlorogenic acid biosynthesis: characterization of a light-induced microsomal 5-o-(4-coumaroyl)-d-quinate/shikimate 3'-hydroxylase from carrot (daucus carota l.) cell suspension cultures.microsomal preparations from carrot (daucus carota l.) cell suspension cultures catalyze the formation of trans-5-o-caffeoyl-d-quinate (chlorogenate) from trans-5-o-(4-coumaroyl)-d-quinate. trans-5-o-(4-coumaroyl)shikimate is converted to about the same extent to trans-5-o-caffeoylshikimate. trans-4-o-(4-coumaroyl)-d-quinate, trans-3-o-(4-coumaroyl)-d-quinate, trans-4-coumarate, and cis-5-o-(4-coumaroyl)-d-quinate do not act as substrates. the reaction is strictly dependent on molecular oxygen a ...19872821918
studies on the introduction and mobility of the maize activator element in arabidopsis thaliana and daucus carota.we have co-transformed carrot (daucus carota) and arabidopsis thaliana with an agrobacterium tumefaciens non-tumorigenic t-dna carrying the maize transposable element activator (ac) and an agrobacterium rhizogenes ri t-dna. we present evidence that the ac element transposes in transformed root or root-derived callus cultures of both species. we show that fertile plants can be regenerated from transformed, root-derived callus cultures of arabidopsis, demonstrating the utility of the ri plasmid fo ...19872832144
effects of nitrogen fertilizer and weed control on nutritive quality of carrots (daucus carota l.).the nutritive quality of carrots, obtained from different herbicide-treated plots and under different levels of nitrogen application ranging from zero to 80 kg nitrogen/ha, was compared. there were significant differences in carotene content, t.s.s. (total soluble solids) and organoleptic characteristics under the influence of different treatments. the maximum carotene content, t.s.s. and organoleptic characteristics were observed with the application of 80 kg. nitrogen/ha and fluchloralin herbi ...19882852805
in vitro inhibition of carrot chalcone synthase by 3'-nucleotidase: the role of the 3'-phosphate group of malonyl-coenzyme a in flavonoid biosynthesis.in mixing experiments with extracts derived from two cell lines of daucus carota tissue cultures with and without chalcone synthase activity, strong inhibition of chalcone synthase (chs) became obvious. this inhibition was due to the presence of a heatlabile protein in extracts from cells devoid of chs activity. this protein was partially purified and identified as 3'-nucleotidase (ec 3.1.3.6). inhibition was also observed in the presence of purified 3'-nucleotidase from lolium multiflorum. the ...19863008651
multiple mutations in the transferred regions of the agrobacterium rhizogenes root-inducing plasmids.agrobacterium rhizogenes induces root formation at the site of inoculation in plants and inserts fragments of its ri plasmid into the plant nuclear dna. the transferred region (t-dna) of the ri plasmid of the a. rhizogenes strain a4 is made of two fragments, namely tl and tr; the latter harbors a sequence homology with the tms loci (responsible for auxin synthesis) of a. tumefaciens. on daucus carota slices, single insertion mutations on the tl region of a. rhizogenes do not confer a mutant phen ...19863012616
characterization of beta-fructosidase, an extracellular glycoprotein of carrot cells.seedlings and suspension-cultured cells of carrot (daucus carota) contain a cell wall associated as well as a soluble form of beta-fructosidase (beta f). these two forms have different ph optima: 4.6 for cell wall beta f and 5.6 for soluble beta f. soluble beta f is relatively more abundant in the seedlings and cell wall beta f is relatively much more abundant in the cultured cells. protoplasts of cultured cells have only the soluble form (ph optimum 5.6) indicating that the cell wall associated ...19883149517
effects of methyl mercury on arrays of microtubules and macromolecular synthesis in daucus carota cultures.cell suspension cultures of daucus carota were exposed to methyl mercury at concentrations between 0 and 6 micrograms/ml for 1, 3, or 24 hr. microtubule arrays exhibited no detectable disruption (as compared with controls) when treated with 1, 2, and 3 micrograms/ml methyl mercury. disorganization of microtubules did occur at higher concentrations (4-6 micrograms/ml) in a concentration/time-dependent manner. no recovery of microtubule arrays was evident when cells were placed in methyl mercury-f ...19873428207
methyl mercury toxicity in plant cultures: modification of resistance and demethylation by light and/or 2,4-dichlorophenoxyacetic acid.cultures of daucus carota, ca-68-10, and lactuca sativa, le-67, were grown at increasing methyl mercury (mehg) concentrations ranging from initial doses of 0.05 to 5.0 micrograms/ml per day for 4 days with or without 0.15 microgram/ml 2,4-dichlorophenoxyacetic acid (2,4-d) in the presence or absence of light. the presence of 2,4-d interacted with light synergistically in the expression of mehg toxicity within the whole range of concentrations. demethylation patterns increased or decreased depend ...19873595486
plasma membrane "rosettes" in carrot and sycamore suspension culture cells.suspension culture cells of carrot, daucus carota l., and sycamore, acer pseudoplatanus l., were freeze-fractured after ultrarapid freezing without fixation or cryoprotection in a propane-jet freezer. infrequently, rosettes (ca. 24 nm diameter) of six (occasionally five) subunits (ca. 8 nm diameter) were observed in p-face views of the plasma membrane of both taxa. when present, rosette density was approximately 1/micron 2. generally, rosettes were less frequently seen on plasma membranes exhibi ...20073835284
transmembrane ferricyanide reduction in carrot cells.carrot cells (daucus carota) grown in tissue culture are capable of reducing the non-permeable electron acceptor, ferricyanide, with concomitant proton extrusion from the cell. optimum conditions for transmembrane ferricyanide reduction include a ph of 7.0-7.5 in a medium containing 10 mm each kcl, nacl and cacl2. data are shown to prove that transmembrane ferricyanide reduction is an enzymatic process. it does not depend on the secretion of phenolics from the cell within the time limits of the ...19853967015
a phosphorus-31 nuclear magnetic resonance study of phosphate uptake and storage in cultured catharanthus roseus and daucus carota plant cells.high resolution 31p nmr spectra (103.2 mhz) of oxygenated catharanthus roseus and daucus carota cells grown in suspension cultures were obtained using a solenoidal perfusion probe. the spectra showed resonances for various phosphorylated metabolites such as atp, adp, nad(p)(h), nucleoside diphosphoglucose, and sugar phosphates. the relative levels of the phosphorylated metabolites remained constant throughout the growth curve. no resonances for storage compounds such as polyphosphates, pyrophosp ...19853972837
chalcone synthase from cell suspension cultures of daucus carota l.chalcone synthase (chs) has been partially purified about 35-fold. withdrawal of 2-mercaptoethanol after precipitation with ammonium sulfate led to higher stability during further purification steps. in order to determine chs activity, two procedures [according to schröder et al. (1979) plant sci. lett. 14, 281-286] were applied. the radioactivity extracted with ethyl acetate from the assay mixture (total products) was compared to 14c-labeled flavanone purified by tlc. the activity of chs increa ...19854015104
anthiovulatory activity of five indigenous plants in rabbits.the petroleum ether, alcoholic, and aqueous extracts of 5 indigenous plants, known to have antifertility activity in female rats and mice (areca catechu linn, carica papaya linn, daucus carota linn, mentha arvensis linn and polygonum hydropiper linn), were evaluated for their possible antiovulatory activity in rabbits with copper-induced ovulation. the alcoholic extract of mentha arvensis (leaves) and the petroleum ether extract of the roots of polygonum hydropiper were the most successful age ...19744442983
tryptophan biosynthesis in nicotiana tabacum and daucus carota cell cultures: site of action of inhibitory tryptophan analogs. 19724536831
anthranilate synthetase from 5-methyltryptophan-susceptible and -resistant cultured daucus carota cells. 19724652566
measurement of the five enzymes which convert chorismate to tryptophan in cultured daucus carota cell extracts. 19734750744
monoamine oxidase inhibiting activity of daucus carota. 19734783391
effect of chromatographic fractions of daucus carota linn. (seeds) on fertility in female albino rats. 19725078109
[demonstration of the nasturtium ringspot virus in the trumpet tree (catalpa bignonioides walt.) and carrots (daucus carota l.)]. 19695396082
kinetin-auxin ratio and development of chloroplasts in tissue cultures of daucus carota. 19705444857
[structure of the carotene crystals of daucus carota]. 19715555933
[formation of chloroplasts in tissue cultures of daucus carota in different hormonal conditions]. 19675618688
[the effect of ammonium ion on glucose metabolism in daucus carota cells]. 19675618690
studies on daucus carota, linn. i. pharmacological studies with the water-soluble fraction of the alcoholic extract of the seeds: a preliminary report. 19665934261
studies on daucus carota linn. ii. cholinergic activity of the quaternary base isolated from water-soluble fraction of alcoholic extract of seeds. 19665979224
isolation and partial characterization of a substance from carrots, daucus carota, with ability to agglutinate cells of streptococcus mutans. 19826184165
a link between transport and plasma membrane redox system(s) in carrot cells.carrot (daucus carota l.) cells grown in suspension culture oxidized exogeneous nadh. the nadh oxidation was able to stimulate k+ (86rb+) transport into cells, but it did not affect sucrose transport. n,n'-dicyclohexyl-carbodiimide, diethylstilbestrol, and oligomycin, which only partially inhibited nadh oxidation, almost completely collapsed the k+ (86rb+) transport. vanadate, which is less effective as an ion transport inhibitor, was less effective in inhibiting the nadh-driven transport of k+ ...19846242153
relative resistance of and delayed toxicity in undifferentiated plant cells to methyl mercury.meristematic cells of carrot (daucus carota l., ca68-10) and lettuce (lactuca sativa l., le-67) cultured in 71-v medium (with 0.15 microgram/ml 2, 4-d) were given one initial dose (0.0001, 0.001, or 0.01 microgram/ml) of methyl mercury (mehg) at 0 hr, cultured for 288 hr. and then subcultured for 4 weeks. in another experiment, mehg was added in four daily doses (0.05, 0.10, 0.50, 1.0, 2.5, or 5.0 micrograms/ml) starting at 72 hr for 120 hr and then subcultured for 168 hr. the resulting 50% grow ...19846510322
the effect of aldicarb on nematode population and its persistence in carrots, soil and hydroponic solution.aldicarb, temik 15 g, was incorporated in furrows at 3.37 and 6.73 kg ai (active ingredient)/ha and carrots (daucus carota l.) were directly seeded on the same day. the numbers of nematode larvae were significantly suppressed in the treated plots; averages were 249, 74, and 51/50 cc soil samples for control (0), 3.37 and 6.73 kg ai/ha, respectively. aldicarb treatment resulted in a 28% yield increase as compared to the untreated. aldicarb residue in carrots was 28 ppb for the low treatment and 4 ...19846747220
research on plants for fertility regulation in india.this present review of indian plants investigated for fertility regulation includes published literature of the country and unpublished data of the central drug research institute (cdri), located in lucknow, india. publications without supportive experimental data have not been included. it is evident from the data presented in the tables that most of the investigators have failed to include the valuable information on the time and place of collection and proper botanical authentication, if co ...19826752588
active polypeptide fragments common to prokaryotic, eukaryotic, and mitochondrial dna polymerases.with a procedure that allows the renaturation of the dna polymerase catalytic activity in situ after sds-polyacrylamide gel electrophoresis, we have compared the active polypeptides present in extracts from organisms covering a wide evolutionary range from prokaryotes to eukaryotes, namely: escherichia coli, oryza sativa, daucus carota , neurospora crassa, dictyostelium discoideum, saccharomyces cerevisiae, ceratitis capitata, leucophaea maderae , xenopus laevis, rat tissues and human lymphoblas ...19826765191
kinetics of golgi apparatus membrane flux following monensin treatment of embryogenic carrot cells.ultrastructural changes resulting from treatment with the sodium selective ionophore, monensin, were studied in embryogenic suspension cultures of carrot, daucus carota (l.) in the presence of 10 microm monensin, an early change in the golgi apparatus was an increase in the number of cisternae per stack (dictyosome). an average of one additional cisterna per stack was formed within the first 2 to 4 min of monensin treatment; in some experiments a second cisterna was formed within about 8 min. th ...19836852059
structure of t-dna in roots transformed by agrobacterium rhizogenes.dna isolated from hairy roots incited on daucus carota by agrobacterium strains harboring the ri plasmid was probed with ri plasmid fragments to identify plasmid sequences transferred and integrated into the plant genome. one hairy root line was incited by an a. rhizogenes natural isolate strain harboring two large plasmids in addition to the ri plasmid. dna from hairy roots incited by this strain contained a total of five nonidentical copies of t-dna which together comprised a t-dna complement ...19836875427
analysis of the garden carrot (daucus carota l.) for linear furocoumarins (psoralens) at the sub parts per million level. 20147096793
hepatoprotective activity of carrot (daucus carota l.) against carbon tetrachloride intoxication in mouse liver.the effect of carrot extract on carbon tetrachloride (ccl4)-induced acute liver damage was evaluated. the increased serum enzyme levels (viz., glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, lactate dehydrogenase, alkaline phosphatase, sorbitol and glutamate dehydrogenase) by ccl4-induction were significantly lowered due to pretreatment with the extract. the extract also decreased the elevated serum bilirubin and urea content due to ccl4 administration. increased activities ...19957500638
complementary immunolocalization patterns of cell wall hydroxyproline-rich glycoproteins studied with the use of antibodies directed against different carbohydrate epitopes.antisera raised against the major hydroxyproline-rich glycoprotein (hrgp) in carrot (daucus carota l.) taproot, extensin-1, and a minor hrgp, extensin-2, were characterized by western blot analysis, enzyme-linked immunosorbent assay, and periodate oxidation and found to be directed against carbohydrate epitopes shared by both glycoproteins. the anti-extensin-1 antibodies (ge1) target periodate-sensitive epitopes and may recognize the terminal alpha-1,3-arabinoside of extensin-1. the anti-extensi ...19937506427
comparative study of the fermentative characteristics of inulin and different types of fibre in rats inoculated with a human whole faecal flora.it is known that the physico-chemical characteristics of fibre modify their fermentation characteristics in the colon. previously we showed the varying effects of inulin and different types of fibre on the hepatic and intestinal xenobiotic-metabolizing enzymes (xme) in initially germ-free rats inoculated with a human, methanogenic, whole-faecal flora (roland et al. 1994). the aim of the present work was to assess whether or not these effects could be related to differences in production of ferme ...19957547841
cloning of a carrot cdna for a member of the family of adp-ribosylation factors (arfs) and characterization of the binding of nucleotides by its product after expression in e. coli.a cdna clone, designated dcarf1, was isolated from a cdna library prepared from embryogenic cell clusters of daucus carota and characterized. the cdna (883 bp) contained an open reading frame that encoded a protein of 181 amino acid residues with significant homology to the adp-ribosylation factors (arfs) of animals and yeast. the dcarf1-related transcripts were detected at a nearly constant level during somatic embryogenesis. the dcarf1-encoded protein was expressed as a fusion protein in e. co ...19957551586
nucleotide sequence of the atpase a- and b-subunits of the halophilic archaebacterium haloferax volcanii and characterization of the enzyme.using pcr with degenerate oligonucleotides, we amplified two conserved regions of the plasma membrane atpase a (alpha)- and b (beta)-subunit-encoding genes from haloferax volcanii, a halophilic archaeon. the amplified fragments were cloned and sequenced, and then used as homologous probes to clone genomic restriction fragments, one of which contained the nearly complete atpa- and atpb-gene. to complete the latter one, we sequenced a region of an overlapping fragment using synthetic oligonucleoti ...19957599166
the effects of mastoparan on the carrot cell plasma membrane polyphosphoinositide phospholipase c.when [3h]inositol-labeled carrot (daucus carota l.) cells were treated with 10 or 25 microm wasp venom peptide mastoparan or the active analog mas-7 there was a rapid loss of more than 70% of [3h]phosphatidylinositol-4-monophosphate (pip) and [3h]phosphatidylinositol-4,5-bisphosphate (pip2) and a 3- and 4-fold increase in [3h]inositol-1,4-p2 and [3h]inositol-1,4,5-p3, respectively. the identity of [3h]inositol-1,4,5-p3 was confirmed by phosphorylation with inositol-1,4,5-p3 3-kinase and co-migra ...19957716245
association of multiple gtp-binding proteins with the plant cytoskeleton and nuclear matrix.several types of gtp-binding proteins exist in plant cells. these include the ras-related low-molecular-weight monomeric gtp-binding proteins and the multi-subunit group which more closely resembles members of the mammalian heterotrimeric g-protein family. proteins belonging to both of these families are known to be involved in cell signalling events and have until recently been assumed to be associated predominantly with membranes. we have investigated the possibility that gtp-binding proteins ...19957741751
cloning, nucleotide sequence and expression of the bifunctional dihydrofolate reductase-thymidylate synthase from glycine max.cdnas encoding the bifunctional dihydrofolate reductase-thymidylate synthase from glycine max were isolated and sequenced. the 1794 base full length cdna contains a single open reading frame of 1593 bases. the predicted size of the encoded protein is 530 amino acids with a molecular weight of 59,707. the protein has two domains: a 226 residue dhfr domain in the n-terminus, which is over 30% identical to human dhfr or the dhfr domain of protozoal dhfr-ts, and a 304 residue thymidylate synthase (t ...19957742362
biochemical, physiological, and molecular characterization of sucrose synthase from daucus carota.sucrose synthase (ec 2.4.1.13) from carrot (daucus carota) is a tetramer with a molecular mass of 320 kd and subunits of 80 kd. the enzyme has a ph optimum of 7.0 (cleavage direction). maximal activities were measured at 55 degrees c. the km for suc was estimated as 87 mm and for udp as 0.39 mm. fructose acts as a noncompetitive inhibitor with an inhibition constant of 17.2 mm. in contrast, glucose inhibits carrot sucrose synthase uncompetitively with an inhibition constant of 4.3 mm. cdna clone ...19957784526
molecular genetics of the maize (zea mays l.) aspartate kinase-homoserine dehydrogenase gene family.aspartate kinase (ak) and homoserine dehydrogenase (hsdh) are enzymes in the aspartate-derived amino acid biosynthetic pathway. recent biochemical evidence indicates that an ak-hsdh bifunctional enzyme exists in maize (zea mays l.). in this report, we characterize three genes that encode subunits of ak-hsdh. two cdnas, pakhsdh1 and pakhsdh2, containing the full-coding sequence, and one partial cdna, pakhsdh3, encode amino acid sequences similar to the reported monofunctional ak and hsdh enzymes ...19947846152
orf250 encodes a second subunit of an abc-type heme transporter in oenothera mitochondria.a highly transcribed region in oenothera mitochondria codes for an open reading frame comprising 250 condons (orf250). this open reading frame shows high sequence similarity to the helc gene of rhodobacter capsulatus which encodes a subunit of a proposed abc-type heme transporter. transcripts of orf250 are edited by cytidine to uridine transitions at 29 sites, altering 10% of all encoded amino acids. genes homologous to helc have also been found in the bacteria bradyrhizobium japonicum and esche ...19957862087
high-performance liquid chromatographic determination of dietary fibre in raw and processed carrots.an hplc method was developed to determine dietary fibre in carrots (daucus carota l.). primary hydrolysis of dietary fibre residue was performed with 12 m h2so4 for 2 h at 40 degrees c and secondary hydrolysis with 0.414 m h2so4 for 3 h at 100 degrees c. for the neutralization step prior to injection, ag4-x4 resin (bio-rad) was used. neutral monosaccharides were separated using an hpx-87p column (bio-rad). this method was applied for evaluation of the quantitative variation of dietary fibre cont ...19947921187
mechanisms of the proliferation and differentiation of plant cells in cell culture systems.plant cell functions have been investigated in various cell culture systems. in this review, we summarize results obtained from investigations of gene expression during the cell cycle in synchronized cultures of catharanthus roseus during somatic embryogenesis in suspension cultures of daucus carota, during organogenesis in tissue cultures of arabidopsis thaliana and during the transdifferentiation of isolated mesophyll cells to tracheary elements in single-cell cultures of zinnia elegans.19947981037
inositol(1,4,5)trisphosphate production in plant cells: stimulation by the venom peptides, melittin and mastoparan.the ability of the amphiphilic peptides, melittin and mastoparan, to modulate the production of inositol(1,4,5)trisphosphate in cultured plant (daucus carota l.) cells was investigated. when added to intact cells melittin and mastoparan caused a rapid and dose-dependent increase in inositol(1,4,5)trisphosphate concentrations. in isolated protoplasts, inositol(1,4,5)trisphosphate levels were 12- to 16-fold higher than in the corresponding cells and neither melittin nor mastoparan was able to sign ...19947999106
the highly edited orf206 in oenothera mitochondria may encode a component of a heme transporter involved in cytochrome c biogenesis.a highly transcribed region in oenothera mitochondria codes for a reading frame (orf206) which shows high homology to the marchantia encoded mitochondrial open reading frame orf277 and is also conserved in the mitochondrial genomes of arabidopsis thaliana and daucus carota. transcripts of orf206 are modified by cytidine to uridine changes in 46 positions by rna editing, affecting 30% of all cytidines and 15% of the total encoded amino acids. this orf is cotranscribed with an upstream reading fra ...19948003696
analysis of the rolc promoter region involved in somatic embryogenesis-related activation in carrot cell cultures.in cell cultures of carrot (daucus carota l.), somatic embryogenesis can be induced by transferring cells from a medium containing 2,4-dichlorophenoxyacetic acid (2,4-d) to one devoid of 2,4-d. previous analysis of transgenic carrot cells containing the 5' non-coding sequence of the ri plasmid rolc and a structural gene for bacterial beta-glucuronidase (uida) has shown that the chimeric gene is actively expressed after induction of somatic embryogenesis. in this study, we demonstrate that activa ...19948016259
cdna cloning of carrot (daucus carota) soluble acid beta-fructofuranosidases and comparison with the cell wall isoenzyme.carrot (daucus carota), like most other plants, contains various isoenzymes of acid beta-fructofuranosidase (beta f) (invertase), which either accumulate as soluble polypeptides in the vacuole (isoenzymes i and ii) or are ionically bound to the cell wall (extracellular beta f). using antibodies against isoenzyme i of carrot soluble beta f, we isolated several cdna clones encoding polypeptides with sequences characteristic of beta fs, from bacteria, yeast, and plants. the cdna-derived polypeptide ...19948016265
[the in vitro action of plants on vibrio cholerae].natural products of several plants, according to the geographic location, are used by peruvian people in the popular treatment of diarrhea, with good success. when cholerae cases appeared in peru, we were interested to know the "in vitro" effect against vibrio cholerae 01, of these useful plants to treat diarrhea. the following plants were tested: cichorium intybus, althaea officinalis, psorela glandulosa, geranium maculatum, punica granatum, malus sativa, cydonia oblonga, chenopodium ambrosoide ...19948018898
a cdna differentially expressed between embryogenic and nonembryogenic carrot (daucus carota l.) cells. 19938022926
novel o-d-galacturonoyl esters in the pectic polysaccharides of suspension-cultured plant cells.driselase digestion of uronate-6-14c-labeled primary walls of cultured spinach (spinacia oleracea l.) cells yielded about 18 novel uronate-containing compounds, most of which could be hydrolyzed by cold dilute alkali to yield oligo-[14c]galacturonides. one typical driselase digestion product (compound 17) yielded alpha-(1-->4)-d-[14c]galacturonotriose(gala3) upon very mild treatment with alkali (50% yield of gala3 in 7.2 min at ph 11 and 25 degrees c). one of the three galacturonate residues in ...19938022945
changes in phosphatidylinositol metabolism in response to hyperosmotic stress in daucus carota l. cells grown in suspension culture.carrot (daucus carota l.) cells plasmolyzed within 30 s after adding sorbitol to increase the osmotic strength of the medium from 0.2 to 0.4 or 0.6 osmolal. however, there was no significant change in the polyphosphorylated inositol phospholipids or inositol phosphates or in inositol phospholipid metabolism within 30 s of imposing the hyperosmotic stress. maximum changes in phosphatidylinositol 4-monophosphate (pip) metabolism were detected at 5 min, at which time the cells appeared to adjust to ...19938029337
voltage-dependent calcium-permeable channels in the plasma membrane of a higher plant cell.numerous biological assays and pharmacological studies on various higher plant tissues have led to the suggestion that voltage-dependent plasma membrane ca2+ channels play prominent roles in initiating signal transduction processes during plant growth and development. however, to date no direct evidence has been obtained for the existence of such depolarization-activated ca2+ channels in the plasma membrane of higher plant cells. carrot suspension cells (daucus carota l.) provide a well-suited s ...19948039493
characterization of a gene that is expressed early in somatic embryogenesis of daucus carota.the emb-1 mrna of carrot (daucus carota) was isolated as an embryo abundant cdna clone (t.h. ulrich, e.s. wurtele, b.j. nikolau [1990] nucleic acids res 18: 2826). northern analyses of rna isolated from embryos, cultured cells, and a variety of vegetative organs indicate that the emb-1 mrna specifically accumulates in embryos, beginning at the early stages of embryo development. in situ hybridization with both zygotic and somatic embryos show that the emb-1 mrna begins to accumulate at low level ...19938108498
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