Publications

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 ...	1985	4015104
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 ...	1985	3972837
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 ...	1985	3967015
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 ...	2007	3835284
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 ...	1987	3595486
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 ...	1987	3428207
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 ...	1988	3149517
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 ...	1986	3012616
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 ...	1986	3008651
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 ...	1988	2852805
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 ...	1987	2832144
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 ...	1987	2821918
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.	1989	2809078
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 ...	1989	2775240
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 ...	1989	2757603
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 ...	1989	2571069
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 ...	1989	2550489
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 ...	1989	2469683
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 ...	1987	2440896
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 ...	1990	2198022
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 ...	1990	2139875
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 ...	1991	2065632
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 ...	1991	1955415
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 ...	1991	1894629
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 ...	1991	1863769
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 ...	1991	1846853
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 ...	1991	1840523
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 ...	1992	1558941
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 ...	1992	1544367
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 ...	1992	1541302
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 ...	1992	1535801
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 ...	1992	1396695
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 ...	1992	1375313
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 ...	1992	1369092
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 ...	1992	1368363
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 ...	1992	1311960
[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 ...	1992	1298018
[induction of anthocyanin biosynthesis in tissue cultures of daucus carota (author's transl)].		1975	1187875
[the influence of gibberellic acid on the synthesis of anthocyanin in tissue cultures of daucus carota (author's transl)].		2005	1187874
pharmacological studies on daucus carota part i.		1975	1178783
the duration of the cell cycle of daucus carota l. in vivo and in vitro.		1975	1132430
estrogenic and pregnancy interceptory effects of carrot daucus carota seeds.		1976	992821
phenylalanine-ammonia-lyase activity and biosynthesis of anthocyanins and chlorogenic acid in tissue cultures of daucus carota (author's transl).		1976	981382
variation of cell cycle duration within suspension cultures of daucus carota and its consequence for the induction of ploidy changes with colchicine.		1976	935509
rapidly-labelled rna species isolated from cell suspensions of daucus carota.		1977	918306
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 ...	1978	669724
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 ...	1978	636662
[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.	1977	595898
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.	1979	521127
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 ...	1979	232596
[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 ...	1976	185135
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 ...	1990	184764
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 ...	2003	156469
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 ...	1977	145403
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.	1978	27444