Publications

characterization of a selenocystine-resistant carrot cell line : alterations in cystine and sulfate uptake.	a selenocystine-resistant carrot cell line, c-1, was isolated from a haploid carrot (daucus carota) cell culture, ha. the c-1 variant takes up cystine, but not cysteine, more slowly than does ha. the selenocystine resistance is maintained in culture in the absence of selection and is expressed in regenerated plants. results based on chromatographic separation of sulfur metabolites from cells fed with [(35)s]cystine suggest a block either in the uptake or reduction of cystine in the variant. both ...	1983	16662864
effects of aspartate and other compounds on glyphosate uptake and growth inhibition in cultured carrot cells.	the strong correlation between glyphosate uptake and growth inhibition of cultured carrot (daucus carota l. cv danvers) cells incubated in the presence of aspartate suggests that aspartate reverses glyphosate inhibition of growth primarily by reducing intracellular glyphosate concentration. other compounds which reverse glyphosate inhibition of cell growth gave a range of effects on glyphosate uptake: succinate, alpha-ketoglutarate, glutamate, pyruvate, and malate at 10 millimolar and phenylalan ...	1983	16662877
characteristics of sulfate transport across plasmalemma and tonoplast of carrot root cells.	compartmental analysis of (35)so(4) (2-) exchange kinetics is used to obtain so(4) (2-) fluxes and compartment contents in carrot (daucus carota l.) storage root cells, where 2 to 5% of the so(4) (2-) taken up is reduced to organic form. the necessary curve fitting is verified by (a) consistency between ;content versus time' and ;rate versus time' plots of washout data; (b) agreement between loading and washout kinetics; and (c) correct identification of the fastest exchange phase as being from ...	1983	16662961
ozone degrades into hydroxyl radical under physiological conditions : a spin trapping study.	defining the reactants is a critical step towards elucidating the mechanism of ozone toxicity to biomembranes. to document ozone-induced ho.radicals, the spin trap 5,5-dimethyl-1-pyrroline-n-oxide was used and the resulting spin adduct was monitored with electron spin resonance spectroscopy. chelexed potassium phosphate buffer (10 millimolar and 0.2 molar) at ph 7.2 and 7.8 was exposed to ozone (1-40 microliters per liter) by directing a stream of ozone over the surface for 60 seconds. under the ...	1983	16663113
selective inhibition of proline hydroxylation by 3,4-dehydroproline.	the effect of proline analogs on peptidyl proline hydroxylation has been studied in vivo using aerated root slices of daucus carota. one analog, 3,4-dehydroproline, acted at micromolar concentrations to rapidly and selectively inhibit peptidyl proline hydroxylation. a structurally altered hydroxyproline-rich cell wall glycoprotein was synthesized and secreted by dehydroproline-treated tissue. the capacity to hydroxylate proline recovered slowly following a short pulse treatment with the analog, ...	1983	16663215
orientation and integrity of plasma membrane vesicles obtained from carrot protoplasts.	two fractions enriched in plasma membrane derived from suspension-cultured carrot (daucus carota l.) cells were examined to determine if they differed from each other either in physical nature or in orientation. parameters studied included the protein composition of purified membranes derived from trypsinized and nontrypsinized protoplasts as well as from trypsinized purified plasma membranes, the effect of inhibitors and membrane perturbants on atpase activity, the binding of [acetyl-(14)c]conc ...	1983	16663225
reinforced polyproline ii conformation in a hydroxyproline-rich cell wall glycoprotein from carrot root.	the salt-extractable hydroxyproline-rich cell wall glycoprotein from carrot (daucus carota l.) roots is composed of 35% (w/w) protein, 3% (w/w) galactose, and 62% (w/w) arabinose. the arabinose is attached to hydroxyproline as tetra- and trisaccharides. the circular dichroism of the glycoprotein shows that it is completely in the polyproline ii conformation. after deglycosylation of the glycoprotein, the polyproline ii conformation of the peptide backbone was lost. this indicates that the carboh ...	1984	16663405
comparative effects of ethylene and cyanide on respiration, polysome prevalence, and gene expression in carrot roots.	treatment of carrot roots (daucus carota l.) with 10 microliters per liter ethylene in o(2) evokes a three- to four-fold increase in polysome prevalence and associated poly(a)(+) rna. the increase in polysome prevalence is attended by a similar change in co(2) evolution. the increase in polysomal poly(a)(+) mrna constitutes primarily a generic increase in constitutive mrnas as assayed by in vitro translation. however, changes in the relative abundance of several in vitro translatable ethylene sp ...	1984	16663623
regulation of the shikimate pathway of carrot cells in suspension culture.	the activity of the first enzyme of the shikimate pathway, 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase, is demonstrated in extracts of daucus carota cells grown in suspension culture. maximum specific enzyme activity is found midway through the logarithmic growth of the culture; cells in lag and stationary phases of growth have lower enzyme levels. the enzyme is activated by tyrosine and tryptophan. the extent of activation varies during cell growth.	1984	16663628
cross-linking of soluble extensin in isolated cell walls.	the extensin component of primary cell walls has generally been considered to be an intrinsically insoluble cell wall glycoprotein. recent data have established that cell wall extensin is in fact secreted in a soluble monomeric form which slowly becomes insolubilized in the cell wall probably through the oxidative formation of isodityrosine cross-links. we now show that isolated cell walls from aerated root slices of daucus carota have the capacity to insolubilize extensin through the formation ...	1984	16663856
selection and characterization of a carrot cell line tolerant to glyphosate.	cultured carrot (daucus carota l.) cells were adapted to growing in 25 millimolar glyphosate by transfer into progressively higher concentrations of the herbicide. tolerance was increased 52-fold, and the adaptation was stable in the absence of glyphosate. the uptake of glyphosate was similar for adapted and nonadapted cells. activity of the enzyme 5-enolpyruvylshikimic acid-3-phosphate synthase was 12-fold higher in the adapted line compared to nonadapted cells, while activities of shikimate de ...	1984	16663884
virulence properties of strains of agrobacterium on the apical and basal surfaces of carrot root discs.	most pathogenic strains of agrobacterium are able to induce crown gall or hairy root on both the apical surface (facing the root tip) and the basal surface (facing the shoot) of carrot (daucus carota l.) root discs. tumorigenic strains carrying mutations in the shoot inhibition region of the t-dna (tl-dna genes 1 and 2) are markedly attenuated on the basal surface but remain virulent on the apical surface. coinoculation of two attenuated tumorigenic strains, with mutations in gene 1 and gene 2, ...	1985	16664012
sensitivity of carrot cell cultures and rna polymerase ii to amatoxins : evidence for the inactivation of 6'-hydroxyamatoxins.	protoplast and cell suspension cultures of daucus carota l. were evaluated for their sensitivity toward the three amatoxin derivatives, alpha-amanitin, 6'-deoxy-alpha-amanitin, and 6'-o-methyl-alpha-amanitin using inhibition of dna synthesis to measure cell viability. protoplasts appeared approximately 10-fold more refractory than suspension cells and alpha-amanitin was much less effective than the other two amatoxins, even though k(i) values for isolated rna polymerase ii were similar (4-5 nano ...	1985	16664072
trehalose as cryoprotectant for the freeze preservation of carrot and tobacco cells.	suspension cultures of carrot (daucus carota, line c1), tobacco (nicotiana tabacum, line tx1), and nicotiana plumbaginifolia (line np) were frozen under controlled conditions with trehalose as the sole cryoprotectant. maximal post-thaw viability (71-74%), measured by phenosafranin dye exclusion, was obtained with the c1 cells following a 24hour pretreatment with 5 or 10% trehalose and with 40% trehalose as the cryoprotectant during freezing. tx1 cells pretreated for 24 hours with 10% trehalose a ...	1985	16664260
localization of cytokinin biosynthetic sites in pea plants and carrot roots.	the biosynthesis of cytokinins was examined in pea (pisum sativum l.) plant organs and carrot (daucus carota l.) root tissues. when pea roots, stems, and leaves were grown separately for three weeks on a culture medium containing [8-(14)c]adenine without an exogenous supply of cytokinin and auxin, radioactive cytokinins were synthesized by each of these organs. incubation of carrot root cambium and noncambium tissues for three days in a liquid culture medium containing [8-(14)c]adenine without c ...	1985	16664274
isolation and partial purification of prophenoloxidase from daucus carota l. cell cultures.	the enzyme, phenoloxidase, was isolated and partially purified as an inactive enzyme, a proenzyme, from plant cell cultures of daucus carota, nicotiana tabacum, and haplopappus gracilis. the prophenoloxidase was found to be specifically activated by ca(2+) or mn(2+) ions in concentrations above 1 millimolar. calmodulin was not involved in this activation. concentrations of ca(2+) or mn(2+) below 1 millimolar could not induce activation of the prophenoloxidase, but if trypsin was added simultaneo ...	1985	16664316
intracellular calcium and calmodulin involvement in protoplast fusion.	(45)ca(2+) uptake was compared between fusogenic and nonfusogenic daucus carota l. protoplasts. fusogenic protoplasts took 10 minutes to reach calcium equilibrium compared to 5 minutes in the nonfusogenic protoplasts. intracellular stores of calcium were manipulated by isolating protoplasts in different calcium regimes. lowering of intracellular calcium lowered fusion potential, while raising intracellular stores of calcium enhanced fusion potential. regardless of the amount of calcium sequester ...	1985	16664381
3-deoxy-d-arabino-heptulosonate 7-phosphate synthase from carrot root (daucus carota) is a hysteretic enzyme.	roots of carrots (daucus carota) contain three activities of 3-deoxy-d-arabino-heptulosonate 7-phosphate (dahp) synthase, the enzyme that catalyzes the first step of the shikimate pathway. the three activities, enzymes i, ii, and iii, are separated by chromatography on phosphocellulose. enzyme iii, purified to electrophoretic homogeneity, has a native molecular weight of 103,000 and consists of two identical subunits of 53,000 daltons each. double reciprocal plots of reaction velocity versus sub ...	1985	16664489
identification and isolation of single cells that produce somatic embryos at a high frequency in a carrot suspension culture.	a system was established in which single cells differentiated to embryos at a high frequency. small spherical single cells from a carrot (daucus carota l. cv "kurodagosun") cell suspension culture were obtained by fractionation through sieving, using nylon screens and then density gradient centrifugation in percoll solutions. eighty-five to 90% of these small single cells differentiated to embryos when they were cultured in a medium containing 2,4-dichlorophenoxyacetic acid (5 x 10(-8) molar), z ...	1985	16664558
calcium transport in tonoplast and endoplasmic reticulum vesicles isolated from cultured carrot cells.	two active calcium (ca(2+)) transport systems have been identified and partially characterized in membrane vesicles isolated from cultured carrot cells (daucus carota danvers). both transport systems required mgatp for activity and were enhanced by 10 millimolar oxalate. ca(2+) transport in membrane vesicles derived from isolated vacuoles equilibrated at 1.10 grams per cubic centimeter and comigrated with cl(-)-stimulated, no(3) (-)-inhibited atpase activity on sucrose density gradients. ca(2+) ...	1986	16664660
cross-linking patterns in salt-extractable extensin from carrot cell walls.	extensins are hydroxyproline-rich glycoproteins (hrgps) found in the primary cell walls of dicots. extensin monomers are secreted into the wall and covalently bound to each other, presumably by isodityrosine (idt) cross-links, to form a rigid matrix. expression of the extensin matrix is correlated with inhibition of cell elongation during normal development and with increased resistance to virulent pathogens. we have isolated extensin from carrot root tissue (daucus carota l.) by published techn ...	1986	16664781
potassium transport in suspension culture cells and protoplasts of carrot.	the properties of potassium transport in carrot (daucus carota l.) suspension culture cells and their isolated protoplasts were examined. cells cultured in murashige and skoog (ms) medium (plant physiol 15: 473-497) were potassium saturated and, consequently, they exhibited little net potassium accumulation. cells that transport and accumulate potassium were derived from the ms-grown cells by culturing them in a potassium-free modified medium. the transport properties of the modified medium cell ...	1986	16664937
carbon assimilation in carrot cells in liquid culture.	assimilation of carbohydrates by carrot (daucus carota l. cv danvers) cells in liquid culture was studied to delineate the major metabolic pathways used in transformation of external carbohydrates to udp-glucose. the cells grown on either sucrose or glucose for several years proved equally capable of utilizing each of these sugars. sucrose was rapidly hydrolyzed extracellularly to glucose and fructose, and glucose was preferentially taken up. uptake of fructose was slower and delayed until gluco ...	1986	16665036
3-deoxy-d-arabino-heptulosonate 7-phosphate synthase from potato tuber (solanum tuberosum l.).	3-deoxy-d-arabino-heptulosonate 7-phosphate synthase, the first enzyme of the shikimate pathway, was purified to electrophoretic homogeneity from tubers of solanum tuberosum l. cv superior. the enzyme is a dimer with a native molecular weight of 110,000. the enzyme appears to be hysteretic. the enzyme activity is stimulated by mn(2+) and l-tryptophan. chromatofocusing resolved two forms of the enzyme with isoelectric points of 7.8 and 8.4, respectively. the enzyme closely resembles an analogous ...	1986	16665132
myo-inositol trisphosphate mobilizes calcium from fusogenic carrot (daucus carota l.) protoplasts.	to determine whether or not inositol trisphosphate (ip(3)) mobilizes calcium in higher plant cells, we investigated the effect of ip(3) on ca(2+) fluxes in fusogenic carrot (daucus carota l.) protoplasts. the protoplasts were incubated in (45)ca(2+)-containing medium and the (45)ca(2+) associated with the protoplasts was monitored with time. addition of ip(3) (20 micromolar) caused a 17% net loss of the accumulated (45)ca(2+) within 4 minutes. there was a reuptake of (45)ca(2+) and the protoplas ...	1987	16665256
purification of a trypsin inhibitor secreted by embryogenic carrot cells.	a protease inhibitor with a molecular weight of about 12,800 was purified to electrophoretic homogeneity from daucus carota cells. the protease inhibitor was heat stable and inhibited trypsin but had no activity toward chymotrypsin or subtilisin. nonembryogenic as well as embryogenic strains contained the inhibitor in similar amounts, but in the embryogenic strains the trypsin inhibitor was released from the cells and as a result accumulated in high concentrations in the culture medium, whereas ...	1987	16665398
polyamine uptake in carrot cell cultures.	putrescine and spermidine uptake into carrot (daucus carota l.) cells in culture was studied. the time course of uptake showed that the two polyamines were very quickly transported into the cells, reaching a maximum absorption within 1 minute. increasing external polyamine concentrations up to 100 millimolar showed the existence of a biphasic system with different affinities at low and high polyamine concentrations. the cellular localization of absorbed polyamines was such that a greater amount ...	1987	16665446
isolation and characterization of aba-insensitive cell lines of carrot.	while abscisic acid (aba) exerts multiple effects on somatic embryogenesis, the most pronounced of these effects is the arrestment of torpedo-stage embryos, preventing them from developing into plantlets. in order to understand the mechanism of aba inhibition of plantlet formation, we have isolated seven aba-insensitive cell lines capable of developing into plantlets in the presence of aba. these aba-insensitive cell lines, whose frequency of appearance is 7 x 10(-6), have been isolated from a h ...	1987	16665552
control of wild carrot somatic embryo development by antioxidants : a probable mode of action of 2,4-dichlorophenoxyacetic acid.	as we previously reported for glutathione (gsh), both ascorbic acid (aa) and vitamin e were observed to suppress wild carrot (daucus carota l.) somatic embryogenesis with little concomitant effect on biomass. endogenous concentrations of aa were lower during embryo development than during cell proliferation, exhibiting a temporal pattern nearly identical to that of gsh. gssg (oxidized gsh) reductase was found to be considerably more active in proliferating than in developing cultures, whereas no ...	1987	16665669
osmotically induced proton extrusion from carrot cells in suspension culture.	addition of 200 mm of a polyol to anthocyanin containing carrot (daucus carota l.) cells in suspension culture decreased turgor pressure to zero and induced hyperpolarization of the membrane potential and acidification of the medium due to h(+) extrusion. these changes were shown to be slightly affected by vanadate. in parallel, a decrease in intracellular atp and total adenylate concentrations were observed. however, when the osmoticum was nacl acidification of the medium occurred in the absenc ...	1987	16665707
binding of glycolytic enzymes to a particulate fraction in carrot and sugar beet storage roots : dependence on metabolic state.	numerous studies have demonstrated a rapid increase in the respiration rate during aging of slices of tuber and storage roots. to determine the molecular mechanisms of this phenomenon, the role of enzyme binding to the subcellular particulate fraction has been assessed in carrot (daucus carota l.) and sugar beet (beta vulgaris l.). soluble versus particulate fractions were separated by centrifugation at 16,000g and both fractions assayed for the activities of six glycolytic enzymes. preparations ...	1988	16665910
comparison of starch and adp-glucose pyrophosphorylase levels in nonembryogenic cells and developing embryos from induced carrot cultures.	cultures of carrot (daucus carota l.) in a medium without added 2,4-dichlorophenoxyacetic acid were separated into fractions of embryos at different stages of development (large globular and heart, torpedo, and germinating) and nonembryogenic cells. the average starch content per cell in these fractions was similar. however, due to the smaller sizes of the cells of the embryos relative to the nonembryogenic cells, starch content per weight of tissue was higher in the embryos. the adp-glucose pyr ...	1988	16665929
transport and subcellular localization of polyamines in carrot protoplasts and vacuoles.	putrescine and spermidine uptake in carrot (daucus carota l., cv "tip top") protoplasts and isolated vacuoles was studied. protoplasts and vacuoles accumulated polyamines very quickly, with maximum absorption within 1 to 2 minutes. the insertion of a washing layer containing 100 millimolar unlabeled putrescine or spermidine did not change this pattern, but strongly reduced the uptake of putrescine and spermidine in protoplasts and in vacuoles. the dependence of spermidine uptake on the external ...	1988	16666174
polyamines in relation to growth in carrot cell cultures.	changes in polyamine metabolism were investigated in relation to growth of cell suspension cultures of carrot (daucus carota, cv chantenay). changes in levels of the major amines putrescine and spermidine throughout the culture period correlated poorly with changes in fresh weight, but a closer correlation with the minor component spermine was observed. the arginine decarboxylase (adc) inhibitor difluoromethylarginine (dfma) strongly and specifically inhibited adc activity in the supernatant, re ...	1988	16666271
plant plasma membrane proteins : ii. biotinylation of daucus carota protoplasts and detection of plasma membrane polypeptides after sds-page.	the ability of two biotinylating reagents, sulfosuccinimidobiotin and sulfosuccinimidyl 2-(biotinamido)ethyl-1,3'-dithiopropionate, to label plasma membrane proteins was examined. these compounds form covalent bonds with the free amino groups of proteins and label the proteins with biotin. biotinylated proteins can be detected with avidin-peroxidase staining. protoplasts isolated from embryogenic daucus carota suspension cells were labeled with biotin and the membranes were separated on linear s ...	1988	16666324
phosphatidylcholine synthesis: differing patterns in soybean and carrot.	the methylation steps in the biosynthesis of phosphatidylcholine by tissue culture preparations of carrot (daucus carota l.) and soybean (glycine max), and by soybean leaf discs, have been studied. preparations were incubated with tracer concentrations of l-[(3)h(3)c]methionine and the kinetics of appearance of radioactivity in phosphomethylethanolamine, phosphodimethylethanolamine, phosphocholine, phosphatidylmethylethanolamine, phosphatidyldimethylethanolamine, phosphatidylcholine, methylethan ...	1988	16666397
promoter strength comparisons of maize shrunken 1 and alcohol dehydrogenase 1 and 2 promoters in mono- and dicotyledonous species.	promoter strengths of two maize alcohol dehydrogenase genes, adh1 and adh2, and the maize shrunken-1 gene, sh1, were evaluated by transient expression in cultured protoplasts of panicum maximum, triticum monococcum, and daucus carota. promoter elements were ligated in correct and opposite orientations as transcriptional gene fusions to the chloramphenicol acetyl transferase gene containing the nopaline synthase 3' polyadenylation signal. the relative levels of gene expression were compared to th ...	1988	16666422
substrate utilization by suspension cultures and somatic embryos of daucus carota l. measured by c nmr.	the uptake and utilization of sucrose by embryogenic suspension cultures of carrot (daucus carota l.) growing in the presence of 2,4-d and by somatic embryos derived from these cultures was monitored using (13)c nuclear magnetic resonance. the exogeneously supplied sucrose was completely hydrolyzed before cell entry; glucose was taken up preferentially when the cells were cultured in the presence of 2,4-d, while glucose and fructose were utilized at similar rates by somatic embryos in the absenc ...	1988	16666463
enzymes of phosphatidylcholine synthesis in lemna, soybean, and carrot.	cell-free extracts from lemna and suspension cultured carrot (daucus carota l.) catalyze s-adenosylmethionine-dependent n-methylations of phosphoethanolamine, phosphomethylethanolamine, and phosphodimethylethanolamine; extracts of suspension cultured soybean (glycine max), of phosphoethanolamine only. material pelleted from each tissue between 15,000 and 100,000g catalyzes s-adenosylmethionine-dependent n-methylations of phosphatidylmethylethanolamine and phosphatidyl-dimethylethanolamine, but n ...	1988	16666464
characterization of inositol phosphates in carrot (daucus carota l.) cells.	we have shown previously that inositol-1,4,5-trisphosphate (ip(3)) stimulates an efflux of (45)ca(2+) from fusogenic carrot protoplasts (m rincón, wf boss [1987] plant physiol 83: 395-398). in light of these results, we suggested that ip(3) might serve as a second messenger for the mobilization of intracellular ca(2+) in higher plant cells. to determine whether or not ip(3) and other inositol phosphates were present in the carrot cells, the cells were labeled with myo-[2-(3)h]inositol for 18 hou ...	1989	16666502
apparent inhibition of beta-fructosidase secretion by tunicamycin may be explained by breakdown of the unglycosylated protein during secretion.	suspension-cultured carrot (daucus carota) cells synthesize and secrete beta-fructosidase, a glycoprotein with asparagine-linked glycans. treatment of the cells with tunicamycin completely inhibits the apparent secretion of beta-fructosidase as measured by the accumulation of the radioactive protein in the cell wall or the culture medium. in the past, such a result has been interpreted as an inhibition of secretion by tunicamycin, but we suggest another explanation based on the following results ...	1989	16666631
udp-glucose: (1,3)-beta-glucan synthase from daucus carota l. : characterization, photoaffinity labeling, and solubilization.	the membrane-bound udp-glucose-beta-(1,3)-glucan synthase from daucus carota l. was characterized and a solubilization procedure was developed. the enzyme exhibited maximal activity in the presence of 0.75 millimolar ca(2+), 0.5 millimolar egta, and 5 millimolar cellobiose at ph 7.5 and 30 degrees c at 1 millimolar udpg. reaction products were confirmed to be (1,3)-linked glucan. polypeptides of 150, 57, and 43 kilodaltons were labeled with the photoactivatible affinity label 5-azido-uridine 5'- ...	1989	16666718
influence of boron on the membrane potential in elodea densa and helianthus annuus roots and h extrusion of suspension cultured daucus carota cells.	when following the membrane potential of elodea densa leaf cells during a dark-light regime and analysing the different phases of the cycle, the pattern under boron deficiency resembled the one reported to occur after 3-(3,4-dichlorophenyl)-1,1-dimethylurea application. the potential in the dark slowly decreased when transferring elodea densa leaflets and helianthus annuus roots to a b-free medium and increased in the same way after b was added again. addition of vanadate to inhibit plasmalemma ...	1989	16666749
synthesis of methylated ethanolamine moieties: regulation by choline in soybean and carrot.	cultured cell suspensions of both carrot (daucus carota l.) and soybean (glycine max) take up exogenous choline efficiently from their respective growth media. during sustained growth at a concentration near 50 micromolar choline, this compound was taken up at rates which exceeded those at which phosphatidylcholine, is synthesized by cells growing in standard (i.e. choline-free) media. in 50 micromolar choline, both types of cells metabolized this compound to phosphocholine and phosphatidylcholi ...	1989	16666754
a comparison between quin-2 and aequorin as indicators of cytoplasmic calcium levels in higher plant cell protoplasts.	assessment of the regulation of plant metabolism by the calcium ion requires a knowledge of its intracellular levels and dynamics. technical problems have prevented direct measurement of the concentration of intracellular ca(2+) in plant cells in all but a few cases. in this study we show that electropermeabilized protoplasts of daucus carota and hordeum vulgare took up the ca(2+) indicating fluorescent dye methoxyquinoline(o-aminophenoxy)ethane-n,n,n',n'-tetraacetic acid (quin-2) and the ca(2+) ...	1989	16666797
characterization of a xylose-specific antiserum that reacts with the complex asparagine-linked glycans of extracellular and vacuolar glycoproteins.	antibodies were raised against carrot (daucus carota) cell wall beta-fructosidase that was either in a native configuration (this serum is called anti-betaf(1)) or chemically deglycosylated (anti-betaf(2)). the two antisera had completely different specificities when tested by immunoblotting. the anti-betaf(1) serum reacted with beta-fructosidase and many other carrot cell wall proteins as well as with many proteins in extracts of bean (phaseolus vulgaris) cotyledons and tobacco (nicotiana tabac ...	1989	16666870
interruption of somatic embryogenesis in daucus carota l. by 5-bromodeoxyuridine.	embryogenic daucus carota l. cells grown in 9 micromolar 2.4-dichlorophenoxyacetic acid are resistant to greater than 5 micromolar 5-bromodeoxyuridine (brdu). in contrast, 5 micromolar brdu strongly inhibits somatic embryogenesis within 24 hours after transfer of cells to an auxin-free medium. dna synthesis rates in control and brdu-treated cultures are rapid and similar; however, the dna content does not reach levels as great in the presence of brdu as in control cultures. brdu substitutes for ...	1989	16666898
inositol trisphosphate metabolism in carrot (daucus carota l.) cells.	the metabolism of exogenously added d-myo-[1-(3)h]inositol 1,4,5-trisphosphate (ip(3)) has been examined in microsomal membrane and soluble fractions of carrot (daucus carota l.) cells grown in suspension culture. when [(3)h]ip(3) was added to a microsomal membrane fraction, [(3)h]ip(2) was the primary metabolite consisting of approximately 83% of the total recovered [(3)h] by paper electrophoresis. [(3)h]ip was only 6% of the [(3)h] recovered, and 10% of the [(3)h]ip(3) was not further metaboli ...	1989	16667056
the heat shock response of carrot : protein variations between cultured cell lines.	we have defined several parameters surrounding the heat shock response of cultured cells of carrot (daucus carota l.) and have found that these cells exhibit a typical "higher plant" heat shock response. in particular, the resolution of the heat shock proteins (hsps) by two-dimensional polyacrylamide gel electrophoresis (page) has revealed a pattern of proteins very similar to the hsps from soybean; specifically, the low molecular weight class is composed of approximately 15 to 20 different poly ...	1989	16667068
ethylene-like activity of isocyanides.	benzyl isocyanide, cyclohexyl isocyanide, benzyl isocyanate, methyl isocyanate, benzyl isothiocyanate, and methyl isothiocyanate were each tested for ethylene-like activity in a pea (pisum sativum) growth assay. only the isocyanides gave an ethylene-like response; the concentration that gave a half-maximal response was approximately 10 to 15 microliters per liter for each isocyanide, and this activity was inhibited by norbornadiene, a competitive inhibitor of ethylene action. since the isocyanid ...	1989	16667085
coregulation of dihydrofolate reductase and thymidylate synthase in overproducer cell lines of wild carrot.	dihydrofolate reductase (dhfr) and thymidylate synthase (ts) activities are associated with a 285,000 molecular weight enzyme complex in carrot (daucus carota l.). selection for methotrexate (mtx) resistance by stepwise increase of the concentration of mtx results in a high frequency adaptation to mtx with little or no significant increase in dhfr activity. however, when as a second step following mtx selection a specific inhibitor of ts, 5-fluoro-2-deoxyuridine was used, dhfr overproducer lines ...	1989	16667128
purification and interconversion of homoserine dehydrogenase from daucus carota cell suspension cultures.	homoserine dehydrogenase from cell suspension cultures of carrot (daucus carota l.) has been purified to apparent homogeneity by a combination of selective heat denaturation, ion exchange and gel filtration chromatographies, and preparative gel electrophoresis. carrot homoserine dehydrogenase is composed of subunits of equal molecular weight (85,000 +/- 5,000). during purification, the enzyme exists predominantly in two molecular weight forms, 180,000 and 240,000. the enzyme can be reversibly co ...	1989	16667218
immunological characterization of in vitro forms of homoserine dehydrogenase from carrot suspension cultures.	multiple forms of homoserine dehydrogenase (hsdh) from carrot (daucus carota l.) have been identified. one form of hsdh (t-form) has a relative molecular weight of 240,000 and is strongly inhibited by threonine. another form (k-form) has a relative molecular weight of 180,000 and is insensitive to inhibition by threonine. the interconversion of these two forms is dependent upon the presence or absence of threonine and potassium. polyacrylamide electrophoretic gels stained for hsdh activity and p ...	1990	16667288
purification and characterization of aspartate aminotransferase isoenzymes from carrot suspension cultures.	three aspartate aminotransferase isoenzymes were identified from extracts of carrot (daucus carota l.) cell suspension cultures. these isoenzymes were separated by deae chromatography and were analyzed on native gradient polyacrylamide gels. the relative molecular weights of the isoenzymes were 111,000 +/- 5000, 105,000 +/- 5000, and 94,000 +/- 4000 daltons; they were designated forms i, ii, and iii, respectively. form i, the predominant form, has been purified to apparent homogeneity (>300-fold ...	1990	16667320
p nmr observations on the effect of the external ph on the intracellular ph values in plant cell suspension cultures.	(31)p nuclear magnetic resonance (nmr) spectroscopy was used to monitor the response of oil palm (elaeis guineensis) and carrot (daucus carota) cell suspensions to changes in the external ph. an airlift system was used to oxygenate the cells during the nmr measurements and a protocol was developed to enable a constant external ph to be maintained in the suspension when required. phosphonoacetic acid was used as an external ph marker and the intracellular ph values were measured from the chemical ...	1990	16667496
the s-methylmethionine cycle in lemna paucicostata.	the metabolism of s-methylmethionine has been studied in cultures of plants of lemna paucicostata and of cells of carrot (daucus carota) and soybean (glycine max). in each system, radiolabeled s-methylmethionine was rapidly formed from labeled l-methionine, consistent with the action of s-adenosyl-l-methionine:methionine s-methyltransferase, an enzyme which was demonstrated during these studies in lemna homogenates. in lemna plants and carrot cells radiolabel disappeared rapidly from s-methylmet ...	1990	16667513
purification and some properties of a daucus carota lectin which enhances the activation of prophenoloxidase by cacl(2).	carrot (daucus carota) cell cultures were found to secrete a protein, with the molecular weight of 58,000, which could strongly enhance the activation of carrot prophenoloxidase by cacl(2). the protein was isolated from the culture filtrate and purified to electrophoretic homogeneity. the purified protein did also show hemagglutinating activity toward rat as well as rabbit erythrocytes and this activity was inhibitied by n-acetylglucosamine or fetuin.	1990	16667519
abscisic acid regulation of dc8, a carrot embryonic gene.	dc8 encodes a hydrophylic 66 kilodalton protein located in the cytoplasm and cell walls of carrot (daucus carota) embryo and endosperm. during somatic embryogenesis, the levels of dc8 mrna and protein begin to increase 5 days after removal of auxin. to study the role of abscisic acid (aba) in the regulation of dc8 gene, fluridone, 1-methyl-3-phenyl,-5(3-trifluoro-methyl-phenyl)-4(1h)-pyridinone, was used to inhibit the endogenous aba content of the embryos. fluridone, 50 micrograms per millilite ...	1990	16667766
short-term treatment with cell wall degrading enzymes increases the activity of the inositol phospholipid kinases and the vanadate-sensitive atpase of carrot cells.	treating carrot (daucus carota l.) suspension culture cells with a mixture of cell wall degrading enzymes, driselase, resulted in an increase in the percentage of [(3)h]phosphatidylinositol bisphosphate. analysis of the lipid kinase activities in the isolated plasma membranes after whole cell treatment indicated that treatment with driselase (2% weight/volume; the equivalent of 340 units per milliliter of hemicellulase and 400 units per milliliter of cellulase activity) or treatment with hemicel ...	1990	16667922
specific levels of dna methylation in various tissues, cell lines, and cell types of daucus carota.	the level of dna methylation in daucus carota was found to be tissue specific, but no simple correlation between developmental stage or age of tissue and the level of dna methylation was found. among three different suspension culture lines from the same variety grown under identical conditions, large differences in the level of dna methylation were observed. the highest and lowest levels were found in two embryogenic cell lines originating from the same clone. suspension cells from one of the e ...	1991	16667947
conditions favorable for the somatic embryogenesis in carrot cell culture enhance expression of the roic promoter-gus fusion gene.	we obtained carrot (daucus carota) cells possessing the 5'-noncoding sequence of the orf12 gene (roic) of tl-dna of the ri plasmid and a structural gene of bacterial beta-glucuronidase by agrobacterium-mediated transformation. when such cells were cultured in medium containing 2,4-dichlorophenoxyacetic acid, substantial reduction in beta-glucuronidase activity was observed. upon transferring the cells from a 2,4-d-containing medium to one devoid of 2,4-dichlorophenoxyacetic acid, enhanced expres ...	1991	16667958
the role of glutamate dehydrogenase in plant nitrogen metabolism.	in vivo nuclear magnetic resonance spectroscopy, in vitro gas chromatography-mass spectrometry, and automated (15)n/(13)c mass spectrometry have been used to demonstrate that glutamate dehydrogenase is active in the oxidation of glutamate, but not in the reductive amination of 2-oxogiutarate. in cell suspension cultures of carrot (daucus carota l. cv chantenay), primary assimilation of ammonium occurs via the glutamate synthase pathway. glutamate dehydrogenase is derepressed in carbonlimited cel ...	1991	16668014
ethanol-induced injuries to carrot cells : the role of acetaldehyde.	carrot (daucus carota l.) cell cultures show high sensitivity to ethanol since both unorganized cell growth and somatic embryogenesis are strongly inhibited by ethanol at relatively low concentrations (10-20 millimolar). the role of acetaldehyde on ethanol-induced injuries to suspension cultured carrot cells was evaluated. when ethanol oxidation to acetaldehyde is prevented by adding an alcohol-dehydrogenase (ec 1.1.1.1) inhibitor (4-methylpyrazole) to the culture medium, no ethanol toxicity was ...	1991	16668049
purification and immunohistochemical detection of an embryogenic cell protein in carrot.	an embryogenic cell protein from carrot (daucus carota l.), designated ecp31 for embryogenic cell protein and with a relative mass of 31,000, was purified by sequential column chromatographies. its apparent relative mass was estimated to be 120,000 by gel filtration. immunoblotting and immunohistochemical studies showed that ecp31 was preferentially localized in the peripheral cells of clusters of embryogenic cells in the presence of 2,4-dichlorophenoxyacetic acid (2,4-d) and disappeared during ...	1991	16668093
heterogeneity and cell type-specific localization of a cell wall glycoprotein from carrot suspension cells.	ep1, an extracellular protein from carrot (daucus carota) cell suspensions, has been partially characterized by means of an antiserum and a cdna clone. in both embryo and suspension cultures different molecular mass ep1 proteins were detected, some of which (31, 32, 52, and 54 kilodaltons) were bound to the cell wall and released into the medium, whereas others (49, 60, and 62 kilodaltons) were more firmly bound to the cell wall and could be extracted with a salt solution. immunoprecipitation of ...	1991	16668246
modulation of auxin-binding proteins in cell suspensions : i. differential responses of carrot embryo cultures.	this paper shows that the level of 2,4-dichlorophenoxyacetic acid (2,4-d) in the medium determines the level of auxin-binding proteins in the membranes of carrot, daucus carota, cells grown in suspension. this induction takes slightly more than 2 hours to complete and can be elicited by natural as well as synthetic auxins. the auxin binding sites thus generated, which are pronase-sensitive, bind 2,4-d, indoleacetic acid, and naphthalene-acetic acid (naa) equally well. however both alpha- and bet ...	1991	16668416
rapid purification and thermostability of the cytoplasmic aspartate aminotransferase from carrot suspension cultures.	several isoenzymic forms of aspartate aminotransferase (aat) have been identified in protein extracts from carrot (daucus carota) cell suspension cultures. the cellular location of the major form (form i) of aat in carrot suspension cultures was determined by heat inactivation, subcellular fractionation, and amino acid sequence analysis. in mammalian systems, there are two forms of aat, a heat-stable cytoplasmic form and a heat-labile form in the mitochondria. the thermostability of three isoenz ...	1991	16668442
bifunctional protein in carrot contains both aspartokinase and homoserine dehydrogenase activities.	we have purified homoserine dehydrogenase to homogeneity and subjected polypeptide fragments derived from digests of the protein to amino acid sequencing. the amino acid sequence of homoserine dehydrogenase from carrot (daucus carota) indicates that in carrot both aspartokinase and homoserine dehydrogenase activities reside on the same protein. additional evidence that aspartokinase and homoserine dehydrogenase reside on a bifunctional protein is provided by coelution of activities during purifi ...	1991	16668550
calcium-pumping atpases in vesicles from carrot cells : stimulation by calmodulin or phosphatidylserine, and formation of a 120 kilodalton phosphoenzyme.	ca(2+)-atpases keep cytoplasmic [ca(2+)] low by pumping ca(2+) into intracellular compartments or out of the cell. the transport properties of ca(2+)-pumping atpases from carrot (daucus carota cv danvers) tissue culture cells were studied. atp-dependent ca(2+) transport in vesicles that comigrated with an endoplasmic reticulum marker, was stimulated three- to fourfold by calmodulin. cyclopiazonic acid (a specific inhibitor of the sarcoplasmic/endoplasmic reticulum ca(2+)-atpase) partially inhibi ...	1991	16668581
regulation of glutamate dehydrogenase activity in relation to carbon limitation and protein catabolism in carrot cell suspension cultures.	glutamate dehydrogenase (gdh) specific activity and function have been studied in cell suspension cultures of carrot (daucus carota l. cv chantenay) in response to carbon and nitrogen supply in the culture medium. the specific activity of gdh was derepressed in sucrose-starved cells concomitant with protein catabolism, ammonium excretion, and the accumulation of metabolically active amino acids. the addition of sucrose led to a rapid decrease in gdh specific activity, an uptake of ammonium from ...	1992	16668745
immunological detection of acetaldehyde-protein adducts in ethanol-treated carrot cells.	polyclonal antibodies able to recognize protein-acetaldehyde conjugates were produced and characterized. the antibodies react with sodium cyanoborohydride-reduced schiff's bases between acetaldehyde and a protein, independently of the nature of the macromolecule binding the acetaldehyde moiety. only conjugates between acetaldehyde or propionaldehyde and a protein are recognized; conjugates obtained with other aldehydes are not reactive. results concerning the formation of acetaldehyde adducts wi ...	1992	16668764
a wound-inducible glycine-rich protein from daucus carota with homology to single-stranded nucleic acid-binding proteins.	a cdna clone was isolated that encodes a wound-inducible glycine-rich protein. the homology of the carrot (daucus carota) protein with the a1 protein of the heterogeneous ribonucleoprotein complex suggests that the polypeptide plays a role in the biosynthesis and processing of heterogeneous nuclear rna and in the maturation of specific mrnas in response to wounding.	1992	16669093
differential accumulation of biotin enzymes during carrot somatic embryogenesis.	the activities of four biotin enzymes, acetyl-coenzyme a (coa) carboxylase, 3-methylcrotonyl-coa carboxylase, pyruvate carboxylase, and propionyl-coa carboxylase, and the accumulation of six biotin-containing polypeptides were determined during development of somatic embryos of carrot (daucus carota). acetyl-coa carboxylase activity increased more than sevenfold, whereas the activities of 3-methylcrotonyl-coa carboxylase, pyruvate carboxylase, and propionyl-coa carboxylase were relatively unalte ...	1992	16669096
tissue-specific accumulation of carotenoids in carrot roots.	raman spectroscopy can be used for sensitive detection of carotenoids in living tissue and raman mapping provides further information about their spatial distribution in the measured plant sample. in this work, the relative content and distribution of the main carrot (daucus carota l.) root carotenoids, alpha-, beta-carotene, lutein and lycopene were assessed using near-infrared fourier transform raman spectroscopy. the pigments were measured simultaneously in situ in root sections without any p ...	2006	16699778
reduced expression of top1beta gene induces programmed cell death and alters ascorbate metabolism in daucus carota cultured cells.	topoisomerase i (topo i) is a nuclear enzyme which plays a fundamental role in several pathways involving changes in dna topology. the topo i-mediated reaction is accomplished by the transient covalent binding of the enzyme to dna (topo i-dna complex). stabilization of the topo i-dna complex, leading to irreversible double-strand breaks, has been reported to occur in animal cells under oxidative stress conditions and during apoptosis. in order to study the existence of a putative link between th ...	2006	16717060
effect of p availability on temporal dynamics of carbon allocation and glomus intraradices high-affinity p transporter gene induction in arbuscular mycorrhiza.	arbuscular mycorrhizal (am) fungi depend on a c supply from the plant host and simultaneously provide phosphorus to the colonized plant. we therefore evaluated the influence of external p on c allocation in monoxenic daucus carota-glomus intraradices cultures in an am symbiosis. fungal hyphae proliferated from a solid minimal medium containing colonized roots into a c-free liquid minimal medium with high or low p availability. roots and hyphae were harvested periodically, and the flow of c from ...	2006	16751522
pharmacological evidence for the potential of daucus carota in the management of cognitive dysfunctions.	the present study was aimed at investigating the effects of daucus carota seeds on cognitive functions, total serum cholesterol levels and brain cholinesterase activity in mice. the ethanolic extract of daucus carota seeds (dce) was administered orally in three doses (100, 200, 400 mg/kg) for seven successive days to different groups of young and aged mice. elevated plus maze and passive avoidance apparatus served as the exteroceptive behavioral models for testing memory. diazepam-, scopolamine- ...	2006	16755009
daucus carota l. mediated bioreduction of prochiral ketones.	stereoselective reductions of ketones to secondary alcohols are of the utmost importance in organic synthesis. very high selectivities are observed with traditional reducing agents, mainly based on boron or transition metals, complexed with chiral ligands. bioreductions mediated by intact cells from cut plants, vegetables and fruits are attractive alternatives and could facilitate transition towards a more biobased economy. this emerging area highlights the recent results obtained in the aqueous ...	2006	16763677
seed germination in response to chemicals: effect of nitrogen and ph in the media.	seed germination generally presents a peak in the next growing season after a fire. among other factors associated with fire are the increase of soil nitrogen and changes in the ph of the soil. in this study, we addressed the question, whether or not the germination response of eight species is linked with the increase in ph and nitrogenous compounds in the germination media? we assessed the separate and combined effects of nitrogenous compounds and ph on the percentage and rate of germination o ...	2006	16850869
stoichiometry studies reveal functional properties of kdc1 in plant shaker potassium channels.	functional heteromeric plant shaker potassium channels can be formed by the assembly of subunits from different tissues, as well as from diverse plant species. kdc1 (k(+) daucus carota 1) produces inward-rectifying currents in xenopus oocytes when coexpressed with kat1 and other subunits appertaining to different plant shaker subfamilies. owing to the presence of kdc1, resulting heteromeric channels display slower activation kinetics, a shift of the activation threshold toward more negative memb ...	2006	16920836
kdc2, a functional homomeric potassium channel expressed during carrot embryogenesis.	in daucus carota, the model system for embryogenesis, it has been demonstrated that potassium and k(+) selective channels are involved in embryo development. here, we report the isolation and cloning of a new carrot shaker-like potassium channel, potassium d. carota channel 2 (kdc2), whose expression pattern during somatic embryogenesis proceeds along with the establishment of the polar axes and the settlement of the hypocotyl region. in plants, kdc2 transcript is localized at the shoot level, i ...	2006	16934807
complete plastid genome sequence of daucus carota: implications for biotechnology and phylogeny of angiosperms.	carrot (daucus carota) is a major food crop in the us and worldwide. its capacity for storage and its lifecycle as a biennial make it an attractive species for the introduction of foreign genes, especially for oral delivery of vaccines and other therapeutic proteins. until recently efforts to express recombinant proteins in carrot have had limited success in terms of protein accumulation in the edible tap roots. plastid genetic engineering offers the potential to overcome this limitation, as dem ...	2006	16945140
the dcmaster transposon display maps polymorphic insertion sites in the carrot (daucus carota l.) genome.	dcmaster is a family of pif/harbinger-like class ii transposable elements identified in carrot. we present a modified transposon display molecular marker system allowing amplification of genomic regions containing dcmaster elements. we scored 77 dcmaster transposon display (dcmtd) amplicons, of which 54 (70%) were segregating in the f(2) progeny from the cross between wild and cultivated carrot. segregating amplicons were incorporated into a previously developed molecular linkage map of carrot. ...	2007	17011731
accumulation of p-hydroxybenzoic acid in hairy roots of daucus carota.	we report here the accumulation of p-hydroxybenzoic acid in agrobacterium rhizogenes-induced hairy root cultures of daucus carota. this phenolic acid finds application in food, pharmaceutical and polymer industries. metabolic profiling of phenolics by hplc/esi-ms from these hairy roots showed a considerable amount of p-hydroxybenzoic acid accumulation both in cytosol and in the cell wall. analyses of hcl and naoh treated soluble phenolic fractions resulted in the elution of peaks with same reten ...	2007	17027117
carrot (daucus carota l.).	plants are susceptible to infection by a broad range of fungal pathogens. many horticulturally important crop species lack adequate genetic resistance to disease. studies on potential mechanisms of disease resistance in plants have revealed the importance of a range of pathogenesis-related (pr) proteins with antifungal activity in reducing colonization of plant tissues by pathogens. we are evaluating a range of pr-proteins, through heterologous expression in transgenic carrot tissues, for their ...	2006	17033046
efficacy of eight larvicidal botanical extracts from khaya senegalensis and daucus carota against culex annulirostris.	the failure to discover a significant new class of insecticides has led many researchers back to biodiscovery studies in the search for new and economically viable alternatives. after a preliminary screening of botanical extracts using descending series of concentrations (1,000, 500, 100, 50, and 5 mg/liter), 8 extracts from 2 potential botanical agents, khaya senegalensis (desrousseaux) and daucus carota l., were tested against 4th instars of culex annulirostris (skuse) following the standard w ...	2006	17067042
introduction of the carrot hsp17.7 into potato (solanum tuberosum l.) enhances cellular membrane stability and tuberization in vitro.	we have examined the ability of a carrot (daucus carota l.) heat shock protein gene encoding hsp17.7 (dchsp17.7) to confer enhanced heat tolerance to potato (solanum tuberosum l.), a cool-season crop. the dchsp17.7 gene was fused to a 6xhistidine (his) tag to distinguish the engineered protein from endogenous potato proteins and was introduced into the potato cultivar 'désirée' under the control of the cauliflower mosaic virus (camv) 35s promoter. western analysis showed that engineered dchsp17. ...	2006	17086756
carrot antifreeze protein does not exhibit the polygalacturonase-inhibiting activity of pgip family.	the carrot (daucus carota) antifreeze protein (dcafp) has a strong antifreeze activity and identified as belonging to the plant polygalacturonase-inhibiting protein (pgip) family based on its sequence similarities, including the presence of a leucine-rich repeat (lrr) motif. in this study, yeast two-hybrid technology was used to analyze whether the carrot afp could act as a pgip. the complete dcafp and polygalacturonase (pgase; obtained from fungus alternaria alternata by rt-pcr) coding sequence ...	2006	17112975
enzymatic evidence for the key role of arginine in nitrogen translocation by arbuscular mycorrhizal fungi.	key enzymes of the urea cycle and (15)n-labeling patterns of arginine (arg) were measured to elucidate the involvement of arg in nitrogen translocation by arbuscular mycorrhizal (am) fungi. mycorrhiza was established between transformed carrot (daucus carota) roots and glomus intraradices in two-compartment petri dishes and three ammonium levels were supplied to the compartment containing the extraradical mycelium (erm), but no roots. time courses of specific enzyme activity were obtained for gl ...	2007	17142485
carotenoid biosynthesis structural genes in carrot (daucus carota): isolation, sequence-characterization, single nucleotide polymorphism (snp) markers and genome mapping.	carotenoid pigments are important components of the human diet and carrots are the main dietary sources of the vitamin a precursors alpha- and beta-carotene. carotenoids play essential biological roles in plants and the genes coding for the carotenoid pathway enzymes are evolutionarily conserved, but little information exists about these genes for carrot. in this study, we utilized published carrot sequences as well as heterologous pcr approaches with primers derived from sequence information of ...	2007	17186217
the impact of cu treatment on phenolic and polyamine levels in plant material regenerated from embryos obtained in anther culture of carrot.	the influence of copper sulphate on the regeneration of carrot (daucus carota l.) androgenic embryos and changes in the levels of phenolic substances and polyamines that might be indicative of the response to oxidative stress were investigated. the cultivation on the regeneration medium supplemented with cu(2+) at the concentrations 1 and 10 microm for 15 weeks resulted in significant dose-dependent inhibition of the growth and organogenic ability of carrot embryos. the total content of phenolic ...	2007	17303431
shelf-life extension of minimally processed carrots by gaseous chlorine dioxide.	chlorine dioxide (clo(2)) gas is a strong oxidizing and sanitizing agent that has a broad and high biocidal effectiveness and big penetration ability; its efficacy to prolong the shelf-life of a minimally processed (mp) vegetable, grated carrots (daucus carota l.), was tested in this study. carrots were sorted, their ends removed, hand peeled, cut, washed, spin dried and separated in 2 portions, one to be treated with clo(2) gas and the other to remain untreated for comparisons. mp carrots were ...	2007	17306398
expression of escherichia coli heat-labile enterotoxin b subunit (ltb) in carrot (daucus carota l.).	we expressed the b subunit of enterotoxigenic escherichia coli heat-labile enterotoxin (ltb) encoded by a synthetic codon-optimized gene in carrot. an agrobacterium-mediated transformation method was used. thirty independent transgenic lines were regenerated via somatic embryogenesis after 6 months in culture and were transferred to a greenhouse. gm1-elisa assay was used to assess ltb protein content in mature taproots. some transgenic lines expressed ltb up to 0.3% of the total soluble protein, ...	2007	17310334
[photosynthetic characteristics and coenological survey of lactuca serriola in its invaded area].	lactuca serriola, a national class quarantine object, is a new invasive species in the coastal area of southeast china. the coenological survey showed that because of its big individual, l. serriola could easily form dominant population in its invaded area, and its main accompany species were conyza canadensis, c. bonarinisis, bidentis bipinnata, oenothera laciniata, ipomoea hederacea, setaria viridis, daucus carota, xanthium sibiricum, erigeron annuus, l. indica, humulus scandens, solanum nigru ...	2006	17330472
carrot infection by alternaria radicina in field conditions and results of laboratory tests.	carrot black rot caused by the fungus alternaria radicina (meier) drechsler et eddy, the economically important disease of carrot (daucus carota l.). research was carried out in 2004 and 2005 in order to establish correlation between plant infestation in the field and laboratory experiments. to determine the incidence and severity of the disease in mature crop, a 5-degree scale was used, where 1 meant no visible disease symptoms and 5 meant total foliage infestation. plants were rated individual ...	2006	17390868
a new flavone glycoside from seeds of daucus carota.	phytochemical examination of seeds of daucus carota l. resulted in the isolation of apigenin -4'-o-beta-d-glucoside, kaempferol-3-o-beta-d-glucoside and a new flavone glycoside which was characterised as apigenin-7-o-beta-d-galactopyranosyl-(1-->4)-o-beta-d-mannopyranoside.	1982	17396982
biotransformation of cardenolides by plant cell cultures1.	a culture of daucus carota cell line ca68, previously shown to specifically hydroxylate digitoxigenin at the c-5 position, has been shown also to convert gitoxigenin and oleandrigenin to their corresponding 5beta-hydroxy derivatives. these two products have not been identified previously. 5beta-hydroxygitoxigenin has been identified by physico-chemical methods and data on its mass spectrum and (13)c-nmr spectrum are reported. 5beta-hydroxyoleandrigenin was identified from its high resolution mas ...	1981	17401955
simulation of germination of pioneer species along an experimental drought gradient.	the germination of ten plant species from the iberian peninsula was assessed along a water deficit gradient between -0. 1652 (moist) and -0.4988 mpa (dry) of osmotic potential, created by addition of increasing concentrations of polyethylene glycol (peg 6000) to distilled water in which plants were grown hydroponically. the level and rate of germination of daucus carota and thapsia villosa significantly decreased with decreasing psi. seeds of dactylis glomerata and dittrichia viscosa had positiv ...	2006	17405330
determination of polyacetylenes in carrot roots (daucus carota l.) by high-performance liquid chromatography coupled with diode array detection.	a new high-performance liquid chromatographic method with diode array detection was developed for the separation and simultaneous determination of the carrot polyacetylenes falcarindiol (fadoh), falcarindiol 3-acetate (fadoac) and falcarinol (faoh) in carrot root extracts. the optimal chromatographic conditions were achieved on a c18 column with a linear gradient elution of water and acetonitrile as mobile phases, at the flow rate of 1.0 ml/min. all calibration curves of the three carrot polyace ...	2007	17444217
results of a screening programme to identify plants or plant extracts that inhibit ruminal protein degradation.	one aim of the ec framework v project, 'rumen-up' (qlk5-ct-2001-00 992), was to find plants or plant extracts that would inhibit the nutritionally wasteful degradation of protein in the rumen. a total of 500 samples were screened in vitro using 14c-labelled casein in a 30-min incubation with ruminal digesta. eight were selected for further investigation using a batch fermentation system and soya protein and bovine serum albumin as proteolysis substrates; proteolysis was monitored over 12 h by th ...	2007	17445338