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The rate of NH(4) (+) assimilation by N-limited Selenastrum minutum (Naeg.) Collins cells in the dark was set as an independent variable and the relationship between NH(4) (+) assimilation rate and in vivo activity of phosphoenolpyruvate carboxylase (PEPC) was determined. In vivo activity of PEPC was measured by follow... |
We report here a method for the isolation of high specific activity phosphoglycerate kinase (EC 2.7.2.3) from chloroplasts. The enzyme has been purified over 200-fold from pea (Pisum sativum L.) stromal extracts to apparent homogeneity with 23% recovery. Negative cooperativity is observed with the two enzyme phosphogly... |
We have purified a group of four proteases (molecular mass 26-33 kilodalton) from germinating seeds of maize (Zea mays L. var W64A) using ammonium sulfate and isoelectric precipitations, anion exchange chromatography, and electroelution from preparative nondenaturing polyacrylamide gels. Their appearance in the endospe... |
The marine chlorophyte Dunaliella tertiolecta Butcher responds to a one-step transition from a high growth irradiance level (700 micromoles quanta per square meter per second) to a low growth irradiance level (70 micromoles quanta per square meter per second) by increasing the total amount of light-harvesting chlorophy... |
An experiment was conducted to investigate alterations in uptake and assimilation of NO(3) (-) by phosphorus-stressed plants. Young tobacco plants (Nicotiana tabacum [L.], cv NC 2326) growing in solution culture were deprived of an external phosphorus (P) supply for 12 days. On selected days, plants were exposed to (15... |
The membrane surrounding the oil body contains several different specific polypeptides. To study the biosynthesis and posttranslational modification of these polypeptides we have prepared monoclonal antibodies against purified oil bodies of soybean (Glycine max). Three of the five monoclonals selected recognize a molec... |
Seven chloroplast proteins were localized in Porphyridium cruentum (ATCC 50161) by immunolabeling with colloidal gold on electron microscope sections of log phase cells grown under red, green, and white light. Ribulose bisphosphate carboxylase labeling occurred almost exclusively in the pyrenoid. The major apoproteins ... |
Carbon oxysulfide (COS) was reinvestigated as an inhibitor of active inorganic carbon transport in cells of Synechococcus PCC7942 adapted to growth at low inorganic carbon. COS inhibited both CO(2) and HCO(3) (-) transport processes in a reversible (in the short term) and mixed competitive manner. The inhibition of COS... |
Three abundant proteins of approximate molecular masses of 22, 23, and 24 kilodaltons were purified from potato (Solanum tuberosum L.) tubers by DEAE cellulose and CM-52 cellulose ion exchange column chromatography, electroelution, and high-pressure liquid chromatography (HPLC). Antibodies specific to the gel-purified ... |
An arginase, purified from the leaf of the jack bean, Canavalia ensiformis, can effectively hydrolyze both l- and d-arginine. Arginases, examined from a number of other plant and animal sources, exhibit marked substrate stereospecificity and fail to catabolize d-arginine. In order to provide essential nitrogen, jack be... |
Stamen removal at an early stage of flower development inhibits anthocyanin synthesis and chalcone flavanon isomerase (CHI) enzyme activity in corollas of Petunia hybrida. The inhibition can be overcome by gibberellic acid (GA(3)) application. Gibberellin also induces anthocyanin synthesis in detached, young green coro... |
The maize (Zea mays) leaf is a valuable system to study the sucrose import to sucrose export transition at the cellular level. Rapidly growing and fully heterotrophic cells in the basal part of the young leaf showed a high sucrose synthase (SS) activity. Leaf SS has been purified to homogeneity. By comparison with puri... |
Glyoxysomal membranes from germinating castor bean (Ricinus communis L. cv Hale) endosperm contain an NADH dehydrogenase. This enzyme can utilize extraorganellar ascorbate free-radical as a substrate and can oxidize NADH at a rate which can support intraglyoxysomal demand for NAD(+). NADH:ascorbate free-radical reducta... |
Differential centrifugation and Percoll-gradient centrifugation of protoplast lysates of suspension-cultured cells of sycamore (Acer pseudoplatanus L.) yielded pure amyloplasts. Contamination of the final amyloplast preparation by foreign compartments was assessed by measuring marker enzyme activities. The activity of ... |
The responses of the quantum efficiencies of photosystem (PS) II and PSI measured in vivo simultaneously with estimations of the activities and activation states of NADP-malate dehydrogenase, chloroplast fructose-1,6-bisphosphatase, and ribulose-1,5-bisphosphate carboxylase were used to study the relationship between e... |
A cysteine endopeptidase (EC 3.4.22.-) present in cotyledons of mung bean (Vigna radiata) seedlings was purified to homogeneity, as judged by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). This proteinase has an apparent molecular mass of 33 kilodaltons as estimated by SDS-PAGE and belongs to the... |
The in vivo synthesis of early heat-shock proteins in young leaves of barley (Hordeum vulgare L.) and sorghum (Sorghum bicolor L.) was studied by one- and two-dimensional electrophoresis. Analysis of whole leaf protein patterns demonstrated clearly the enhanced resolution of heat-shock proteins, especially those of low... |
In tomato (Lycopersicon esculentum) several acidic and basic apoplastic pathogenesis-related (PR) proteins are induced upon inoculation with virulent or avirulent races of Cladosporium fulvum (Cooke) (syn. Fulvia fulva [Cooke] Cif). One of the most predominant and best characterized tomato PR proteins is P14, a basic p... |
Developing kernels of the maize (Zea mays) hybrid W64A x W182E germinated precociously following fluridone treatment. Likewise, following premature drying, the kernels germinated upon subsequent rehydration. Tolerance of the aleurone layer to premature desiccation considerably preceded that of the embryo. The increase ... |
Cultured tobacco (Nicotiana tabacum, var Xanthi) cells contain a topoisomerase that removes positive and negative supercoils from DNA. The enzyme has an estimated molecular mass of 30,000 daltons under denaturing conditions, but may exist as a multimeric protein in the native state. Activity is enhanced significantly b... |
Acetohydroxyacid synthase (AHAS) activity was studied in the green unicellular alga Chlorella emersonii. This activity and its regulation was compared in the algae grown autotrophically and heterotrophically on glucose in the dark. No evidence for the existence of more than one enzyme was found. The activity in crude e... |
A method is described for the purification of glutamine synthetase (GS; EC. 6.3.1.2) from the leaves and roots of Pinus banksiana Lamb., a conifer which utilizes ammonium as its primary nitrogen source. The enzyme was purified to apparent homogeneity by a procedure involving salt fractionation as well as ion-exchange, ... |
Incubation of the red beet (Beta vulgaris L.) plasma membrane H(+)-ATPase with micromolar concentrations of diethylpyrocarbonate (DEPC) resulted in inhibition of both ATP hydrolytic and proton pumping activity. Enzyme activity was restored when DEPC-modified protein was incubated with hydroxylamine, suggesting specific... |
The highly conserved protein ubiquitin is involved in several cellular processes in eukaryotes as a result of its covalent ligation to a variety of target proteins. Here, we describe the purification of several enzymatic activities involved in ubiquitin-protein conjugate formation and disassembly from wheat germ (Triti... |
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... |
The mobilization of stored carbohydrates (sucrose and starch) and proteins during sucrose starvation was studied with sycamore (Acer pseudoplatanus L.) cells. When almost all the intracellular carbohydrate pools had disappeared, the cell protein content declined progressively whereas asparagine determined by either (13... |
Synechocystis sp. strain PCC6308 cells were starved for nitrogen for 5 days. The polypeptide compositions of whole cell extracts and washed membranes of nitrogen-replete and nitrogen-starved cells were compared by one- and two-dimensional electrophoresis. Immunoblotting of one-dimensional gels indicated that pelletable... |
A 3' -phosphoadenosine 5' -phosphosulfate (PAPS):desulfoglucosinolate sulfotransferase (EC 2.8.2-) was extensively purified from light-grown cress (Lepidium sativum L.) seedlings by gel filtration and concanavalin A-Sepharose 4B, Matrex Gel Green A, and Mono Q fast protein liquid chromatography. The purified enzyme, wh... |
The use of LaPr 88/29 mutant of barley (Hordeum vulgare), which lacks NADH-preferring hydroxypyruvate reductase (HPR-1), allowed for an unequivocal demonstration of at least two related NADPH-preferring reductases in this species: HPR-2, reactive with both hydroxypyruvate and glyoxylate, and the glyoxylate specific red... |
The glycine decarboxylase multienzyme complex comprises about one-third of the soluble protein of the matrix of pea (Pisum sativum) leaf mitochondria where it exists at a concentration of approximately 130 milligrams protein/milliliter. Under these conditions the complex is stable with an approximate subunit ratio of 2... |
Malate oxidation supported C(2)H(2) reduction by bacteroids isolated from Sesbania rostrata stem nodules. Optimal activity reached 7.5 nanomoles per minute per milligram of dry weight and was in the same order of magnitude as that observed with succinate but always required a lower O(2) tension. Malate dehydrogenase (E... |
Purified potato tuber (Solanum tuberosum L. cv Bintie) mitochondria contain soluble, highly latent NAD(+)- and NADP(+)-isocitrate dehydrogenases, NAD(+)- and NADP(+)-malate dehydrogenases, as well as an NADPH-specific glutathione reductase (160, 25, 7200, 160, and 16 nanomoles NAD(P)H per minute and milligram protein, ... |
Amylase activity is elevated 5- to 10-fold in leaves of several different Arabidopsis thaliana mutants defective in starch metabolism when they are grown under a 12-hour photoperiod. Activity is also increased when plants are grown under higher light intensity. It was previously determined that the elevated activity wa... |
The hydrolytic specificity of a 30 kilodalton cysteine proteinase purified from germinated barley (Hordeum vulgare L. cv Morex) was investigated using high performance liquid chromatography to characterize its hydrolysis of two small barley seed proteins, the alpha- and beta-hordothionins. The reduced and pyridylethyla... |
Petiole growth of Rumex acetosa L., Rumex crispus L., and Rumex palustris Sm. in response to soil waterlogging was studied in relation to production of the gaseous plant hormone ethylene. Ethylene production was monitored in a flow-through system and a recently developed laser driven photoacoustic detection system, whi... |
The effect of external inorganic carbon concentration and light on carbonic anhydrase (CA) protein accumulation and steady-state mRNA levels were examined in Chlamydomonas reinhardtii. When photoautotrophically grown high-CO(2) cells were transferred to low-CO(2) conditions, they exhibited a significant accumulation of... |
Ice plant (Mesembryanthemum crystallinum) is a facultative halophyte that responds to water stress in the form of drought or high salinity by switching from C(3) photosynthesis to Crassulacean acid metabolism (CAM), a physiological adaptation that increases water conservation. Although CAM is clearly environmentally co... |
Tonoplast vesicles were purified from a microsomal fraction isolated from etiolated soybean hypocotyls (Glycine max L.) by preparative free-flow electrophoresis. Marker enzyme determinations and immunoblot analysis against the vacuolar-ATPase confirmed the nature and the purity of the isolated membranes. A purified ton... |
We have shown that highly purified vacuoles of suspension-cultured tomato (Lycopersicon esculentum) cells contain RNA-oligonucleotides, using two different approaches to label and detect RNA: (a) in vivo labeling of cellular RNA with [5-(3)H]uridine, followed by preparation of vacuoles from protoplasts and by quantific... |
Wild type and three abscisic acid (ABA)-insensitive mutants of Arabidopsis (ABI1, ABI2, and ABI3) were compared for their ability to respond to ABA for a variety of ABA-inducible responses throughout the life cycle of the plants. The responses tested included effects on seedling growth, proline accumulation in seedling... |
Lolium rigidum biotype SR4/84 is resistant to the herbicides diclofop-methyl and chlorsulfuron when grown in the field, in pots, and in hydroponics. Similar extractable activities and affinities for acetyl-coenzyme A of carboxylase (ACCase), an enzyme inhibited by diclofop-methyl, were found for susceptible and resista... |
The balance between reactions involving free radicals and processes which ameliorate their effect plays an important role in the regulation of plant senescence. In this study a method was developed to isolate peroxisomes and mitochondria from carnation (Dianthus caryophyllus L. cv Ember) petals. Based on electron micro... |
mRNA obtained from green leaves of lentil (Lens culinaris) was used to construct a cDNA library in phage lambdagt11. The cDNA library was screened with antibodies raised against lentil glycolate oxidase and catalase. Clone CL 1 containing the full-length sequence complementary to glycolate oxidase mRNA was characterize... |
Lysophosphatidate (LPA) acyltransferase (EC 2.3. 1.51) in the microsomes from the maturing seeds of meadowfoam (Limnanthes alba), nasturtium (Tropaeolum majus), palm (Syagrus cocoides), castor bean (Ricinus communis), soybean (Glycine max), maize (Zea mays), and rapeseed (Brassica napus) were tested for their specifici... |
Microsomal membranes isolated from the pericarp of maturegreen tomato (Lycopersicon esculentum) fruit rapidly metabolize exogenous radiolabeled linoleic acid into fatty acid oxidation products at 22 degrees C. The reaction is strongly inhibited by n-propyl gallate, an inhibitor of lipoxygenase. The membranes also rapid... |
The hypoxic stress response of Zea mays L. seedling roots involves regulation of gene expression at transcriptional and posttranscriptional levels. We investigated the effect of hypoxia on the translational machinery of seedling roots. The levels of monoribosomes and ribosomal subunits increased dramatically within 1 h... |
By measuring (18)O exchange from doubly labeled CO(2) ((13)C(18)O(18)O), intracellular carbonic anhydrase activity was studied with protoplasts and chloroplasts isolated from Chlamydomonas reinhardtii grown either on air (low inorganic carbon [C(i)]) or air enriched with 5% CO(2) (high C(i)). Intact low C(i) protoplast... |
The effect of auxin on ribosomal protein phosphorylation of germinating maize (Zea mays) tissues was investigated. Two-dimensional gel electrophoresis and autoradiography of [(32)P] ribosomal protein patterns for natural and synthetic auxin-treated tissues were performed. Both the rate of (32)P incorporation and the el... |
Zeatin O-xylosyltransferase and zeatin O-glucosyltransferase occur in immature embryos of Phaseolus vulgaris and P. lunatus, respectively. Purified preparations of the xylosyltransferase were used as antigen to elicit the formation of antibodies in mice. Hybridoma clones were produced by fusion of mouse spleen cells wi... |
Triazine-resistant plants grown under moderate to high photon flux density (PFD) conditions exhibit decreased photon yield, decreased light-saturated O(2) evolution and slower growth than triazine-susceptible plants. In this study we tested the hypothesis that the comparable growth previously observed in resistant and ... |
Two mutants of barley (Hordeum vulgare L.), LaPr 85/55 and LaPr 87/30, have been isolated that accumulate glycine, with a concomitant reduction in the aminodonors glutamate and alanine, when transferred to air. Studies have shown that these plants have wild-type levels of serine transhydroxymethylase (EC 2.1.2.1) activ... |
Young leaves from Catharanthus roseus plants contain the enzymes which convert the monoterpenoid indole alkaloid, tabersonine by three hydroxylations, two methylations, and one acetylation step to vindoline. A novel direct enzyme assay has been developed for a hydroxylase involved in vindoline biosynthesis, which catal... |
The intracellular compartmentation of ATP sulfurylase and O-acetylserine(thiol)lyase in spinach (Spinacia oleracea L.) leaves has been investigated by isolation of organelles and fractionation of protoplasts. ATP sulfurylase is located predominantly in the chloroplasts, but is also present in the cytosol. No evidence w... |
Roots of Fe-sufficient and Fe-Deficient pea (Pisum sativum L.) were studied to determine the effect of Fe-deficiency on the activity of the root-cell plasmalemma Fe(2+) transport protein. Rates of Fe(III) reduction and short-term Fe(2+) influx were sequentially determined in excised primary lateral roots using Fe(III)-... |
The steady state kinetics of glyceraldehyde 3-phosphate:NADP(+) oxidoreductase (GNR) (EC 1.2.1.9) have been investigated. The enzyme exhibits hyperbolic behavior over a wide range of substrate concentrations. Double-reciprocal plots are nearly parallel or distantly convergent with limiting K(m) values of 2 to 5 micromo... |
Twenty-one monoclonal antibodies were raised against the aspartate aminotransferase-P(2) isoenzyme from root nodules of Lupinus angustifolius [L.] cv Uniharvest. Induction of this isoenzyme is positively correlated with the onset of N(2) fixation in effective root nodules and is associated with the assimilation of ammo... |
Chlorophyll synthesis in Euglena, as in higher plants, occurs only in the light. The key chlorophyll precursor, delta-aminolevulinic acid (ALA), is formed in Euglena, as in plants, from glutamate in a reaction sequence catalyzed by three enzymes and requiring tRNA(Glu). ALA formation from glutamate occurs in extracts o... |
Endo-beta-1,3-glucanase activity in intercellular washing fluid (IWF) from leaves of wheat (Triticum aestivum) increased 10-fold 4 days after leaves were infected with the wheat stem rust fungus (Puccinia graminis f.sp. tritici), while exo-beta-1,3-glucanase activity remained unchanged at a low level. Heat and ethylene... |
The GA(20) 3beta-hydroxylase present in immature seeds of Phaseolus vulgaris has been partially purified and characterized. The physical characteristics of the enzyme are similar to those of the GA 2beta-hydroxylases present in mature and immature seeds of Pisum sativum. It is acid-labile, hydrophobic, and of M(r) 45,0... |
Glutathione reductase (EC 1.6.4.2) was purified from Eastern white pine (Pinus strobus L.) needles. The purification steps included affinity chromatography using 2', 5'-ADP-Sepharose, FPLC-anion-exchange, FPLC-hydrophobic interaction, and FPLC-gel filtration. Separation of proteins by FPLC-anion-exchange resulted in th... |
Hemes destined for cytosolic hemoproteins must originate in one of the cellular compartments which have the capacity for heme synthesis, namely the chloroplast or the mitochondria. Since developing chloroplasts from greening cucumber (Cucumis sativus, cv. Sumter) cotyledons are known to contain complete heme and chloro... |
Phosphoenolpyruvate carboxylase (PEPC) was purified 40-fold from soybean (Glycine max L. Merr.) nodules to a specific activity of 5.2 units per milligram per protein and an estimated purity of 28%. Native and subunit molecular masses were determined to be 440 and 100 kilodaltons, respectively, indicating that the enzym... |
NADPH-dependent reduction of 2',7-dihydroxy-4',5'-methylenedioxyisoflavone to the isoflavanone sophorol, a proposed intermediate step in pisatin biosynthesis, was detected in extracts of Pisum sativum. This isoflavone reductase activity was inducible by treatment of pea seedlings with CuCl(2). The timing of induction c... |
Different parts of the rice (Oryza sativa L.) plant at different growth stages were analyzed for sucrose synthase (SS) by enzyme activity assay and enzyme-linked immunosorbent assay directly on the extracts or on the eluates from a gel filtration column. On a dry matter basis, the amount of soluble protein and SS activ... |
Pollen mother cells of the lily (Lilium speciosum) were found to have a histone-H1-like protein (PMCP) not detected in other tissues. The PMCP appears from the late S-G(2) period of premeiosis and is present in mature pollen. PMCP and H1 were extracted from pollen mother cells with 5% perchloric acid and isolated by re... |
To examine the effects of N nutrition upon endosperm development, maize (Zea mays) kernels were grown in vitro with either 0, 3.6, 7.1, 14.3, or 35.7 millimolar N. Kernels were harvested at 20 days after pollination for determination of enzyme activities and again at maturity for quantification of storage products and ... |
Storage protein gene expression, characteristic of mid- to late embryogenesis, was investigated in microspore embryos of rapeseed (Brassica napus). These embryos, derived from the immature male gametophyte, accumulate little or no detectable napin or cruciferin mRNA when cultured on hormone-free medium containing 13% s... |
The effects of gas phase O(2) concentration (1%, 20.5%, and 42.0%, v/v) on the quantum yield of net CO(2) fixation and fluorescence yield of chlorophyll a are examined in leaf tissue from Nicotiana tabacum at normal levels of CO(2) and 25 to 30 degrees C. Detectable decreases in nonphotochemical quenching of absorbed e... |
The accumulation of alcohol dehydrogenase (ADH) in arachidonic acid-elicited potato (Solanum tuberosum L.) tuber discs was studied. In accordance with our previous report of the accumulation of Adh mRNA beginning 2 hours after elicitor treatment (DP Matton, CP Constabel, N Brisson [1990] Plant Mol Biol 14: 775-783), im... |
Patatin and the 22-kilodalton protein complex make up more than 50% of the soluble protein present in potato (Solanum tuberosum) tubers and these two proteins are coordinately regulated during tuber development. Although genomic sequences related to these tuber genes exist in the genome of potato species that do not be... |
Chlorella strain (UTEX 27) maintains optimal photosynthetic capacity when growing photoautotrophically in the presence of ammonium. Nitrate-grown photoautotrophic cells, however, show a drastic loss of chlorophyll content and ribulose-1,6-bisphosphate carboxylase/oxygenase activity, resulting in a greater than 10-fold ... |
An artificial Na(+) gradient across the envelope (Na(+) jump) enhanced pyruvate uptake in the dark into mesophyll chloroplasts of a C(4) plant, Panicum miliaceum (NAD-malic enzyme type) (J Ohnishi, R Kanai [1987] FEBS Lett 219:347). In the present study, (22)Na(+) and pyruvate uptake were examined in mesophyll chloropl... |
We present the results of two sets of experiments designed to express high methionine proteins in transgenic seeds in three different plant species. In the first approach, two chimeric genes were constructed in which parts of the Arabidopsis 2S albumin gene 1 (AT2S1) were fused at different positions to a Brazil nut 2S... |
The phosphorylation of plasma membrane proteins from red beet (Beta vulgaris L.) by radioactive inorganic phosphate was studied. Only few proteins were phosphorylated, among them was one polypeptide with an apparent molecular weight of about 100,000. The phosphorylation of this protein was decreased when orthovanadate ... |
Leucoplast pyruvate kinase from endosperm of developing castor oil seeds (Ricinus communis L.; cv Baker) has been purified 1370-fold to a specific activity of 41.1 micromoles pyruvate produced per minute per milligram protein. Nondenaturing polyacrylamide gel electrophoresis of the purified enzyme resulted in a single ... |
The cell wall invertase from an Agrobacterium tumefaciens-transformed Nicotiana tabacum cell line (SR1-C58) was purified. The heterogeneously glycosylated enzyme has the following properties: M(r) 63,000, pH optimum at 4.7, K(m sucrose) 0.6 millimolar (at pH 4.7), pl 9.5. Enzyme activity is inhibited by micromolar conc... |
Aspartate aminotransferase (AAT) plays an important role in nitrogen metabolism in all plants and is particularly important in the assimilation of fixed N derived from the legume-Rhizoblum symbiosis. Two isozymes of AAT (AAT-1 and AAT-2) occur in alfalfa (Medicago sativa L.). Antibodies against alfalfa nodule AAT-2 do ... |
Genes encoding wild type acetolactate synthase (ALS) and a sulfonylurea herbicide-resistant form of the enzyme, isolated from Arabidopsis thaliana, were expressed in transgenic Nicotiana tabacum plants under the control of their native promoters or of the highly active cauliflower mosaic virus 35S promoter. Expression ... |
The effects of high light stress on chloroplast ultrastructure and protein and mRNA composition were investigated in carotenoid-deficient peas (Pisum sativum, L.). In low light, the thylakoid membrane polypeptide pattern was altered, with several prominent chlorophyll-binding proteins present in diminished amounts. Thi... |
A full-length cDNA encoding a heat shock protein (hsp) belonging to the 83 to 90 kilodalton hsp family of Arabidopsis thaliana has been isolated and sequenced. Truncated cDNA clones were isolated by nucleic acid hybridization to a truncated soybean HSP83 cDNA probe and a fragment generated from a Drosophila HSP83 gene.... |
Gibberellins (GAs) are a group of plant growth hormones that were first isolated from the fungus Gibberella fujikuroi. The biosynthesis of GA in liquid cultures of the fungus has been examined using high-performance liquid chromatography and combined gas chromatography-mass spectrometry. GA(3) was the predominant GA in... |
Enriched 1,3-beta-glucan and 1,4-beta-glucan synthase fractions from the fungus Saprolegnia were isolated by rate zonal centrifugation on glycerol gradient. Purification was improved by entrapment of the enzymes in their reaction product, i.e. microfibrillar glucans. 1,3-beta-Glucan synthases were separated from 1,4-be... |
A cryoselection protocol has been developed that provides freezing-tolerant callus that, in turn, can regenerate plants with enhanced cold hardiness. Tolerant calli were selected from spring wheat (Triticum aestivum L.) callus by immersion in liquid nitrogen without addition of cryoprotectants. Less than 15% of the cal... |
Effects of the herbicide safeners N,N-diallyl-2,2-dichloroacetamide and 4-dichloroacetyl-3,4-dihydro-3-methyl-2H-1,4-benzooxazin (CGA 154281) on the contents in cysteine and glutathione, on the assimilation of (35)SO(4) (2-), and on the enzymes of assimilatory sulfate reduction were analyzed in roots and primary leaves... |
Pea (Pisum sativum L.) tissues with reduced chloroplast density (e.g. petals and stems) or function (i.e. senescent leaves and leaves darkened for prolonged periods) were surveyed to determine whether tissues with genetically or environmentally reduced chloroplast density and/or function also have significantly differe... |
Redox activities, NADH:ferricyanide reductase, NAD(P)H:cytochrome reductases, and NADH:ascorbate free-radical reductase, are present in endoplasmic reticulum (ER) and glyoxysomal membranes from the endosperm of germinating castor bean (Ricinus comminus L. var Hale). The development of these functions was followed in gl... |
We have previously demonstrated that a protein purified from xylan-induced culture filtrates of Trichoderma viride contains beta-1,4-endoxylanase activity and induces ethylene biosynthesis in tobacco (Nicotiana tabacum cv Xanthi) leaf discs. When the ethylene biosynthesis-inducing xylanase (EIX) was applied to cut peti... |
In many plant species, the daily release of hundreds to thousands of healthy cells from the root cap into the soil is a normal process, whose function is unknown. We studied the separation of the cells in pea (Pisum sativum) using an aeroponic system in which separated cells were retained on the root until they were wa... |
The regulation of an elicitor-inducible sesquiterpene cyclase in tobacco (Nicotiana tabacum) cell suspension cultures was investigated. Sesquiterpene cyclase activity was absent from control cell cultures but induced to a maximum within 15 hours of cellulase addition to the cell cultures. The induction of the cyclase a... |
The first step in the biosynthesis of allylglucosinolate from methionine in Brassica is thought to be the transamination of methionine to 2-keto-4-methylthiobutyrate. By using Q-Sepharose and Red Agarose, followed by high resolution anion exchange chromatography and chromatofocussing, a methionine:glyoxylate aminotrans... |
We have purified a cell wall protein from extracts of soybean (Glycine max) that was previously shown to be immunologically related to p33, a wound-induced carrot cell wall protein (Tierney ML, Wiechert J, Pluymers D [1988] Mol Gen Genet 211: 393-399). Amino acid composition analysis reveals that the protein is 36% pro... |
Parsley (Petroselinum crispum) cell cultures respond rapidly to treatment with fungal elicitor by the accumulation of coumarin phytoalexins in the culture fluid and by incorporation of ferulic esters into their cell walls. S-Adenosyl-l-methionine:trans-caffeoyl-CoA 3-O-methyltransferase activity, specifically involved ... |
Two anionic isoperoxidases were isolated from media of Aspergillus flavus-inoculated cotton (Gossypium hirsutum L.) ovule cultures and purified about 150-fold to apparent homogeneity by treatment with Cell Debris Remover and ion exchange chromatography on Accell QMA medium. These isoperoxidases were present in noninocu... |
To evaluate and characterize stevioside biosynthetic pathway in Stevia rebaudiana Bertoni cv Houten, two enzyme fractions that catalyze glucosylation of steviol (ent-13-hydroxy kaur-16-en-19-oic acid) and steviol-glucosides (steviol-13-O-glucopyranoside, steviolbioside and stevioside), utilizing UDP-glucose as the gluc... |
A cDNA clone encoding a nonspecific lipid transfer protein from spinach (Spinacia oleracea) was isolated by probing a library with synthetic oligonucleotides based on the amino acid sequence of the protein. Determination of the DNA sequence indicated a 354-nucleotide open reading frame which encodes a 118-amino acid re... |
The effects of reductions in growth temperature on the development of thylakoids of maize (Zea mays var LG11) leaves are examined. Thylakoids isolated from mesophyll cells of leaves grown at 17 degrees and 14 degrees C, compared with 25 degrees C, exhibited a decreased accumulation of many polypeptides, which was accom... |
Nitrogen-limited and nitrogen-sufficient cell cultures of Selenastrum minutum (Naeg.) Collins (Chlorophyta) were used to investigate the dependence of NH(4) (+) assimilation on exogenous CO(2). N-sufficient cells were only able to assimilate NH(4) (+) maximally in the presence of CO(2) and light. Inhibition of photosyn... |
4-Methyleneglutamine amidohydrolase has been extracted and purified over 1000-fold from 14-day-old peanut (Arachis hypogaea) leaves by modification of methods described previously. The purified enzyme shows two bands of activity and three to four bands of protein after electrophoresis on nondenaturing gels. Each of the... |
Immunocytochemical studies on Brassica napus (rapeseed) tissues using a monoclonal antibody against myrosinase (thioglucoside glucohydrolase) showed that the enzyme was only present in a small number of cells. In the developing embryo, scattered myrosinase-containing cells were present in both cotyledons and axis. The ... |
By using a peptide (CK-15) based on the COOH-terminal sequence of nodulin-26, we have demonstrated the presence of a Ca(2+)-dependent protein kinase in soluble as well as particulate fractions of nitrogen-fixing soybean (Glycine max) root nodules. Substantial enzyme activity was found in symbiosome membranes. The solub... |
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