| [validation study on a multi-residue method for determination of pesticide residues in agricultural products by new automatic pretreatment equipment (fasrac) and gc-ms/ms]. | a validation study was performed on a multiresidue method for determination of pesticide residues in agricultural products according to the method validation guideline of the ministry of health, labour and welfare of japan. fasrac (food automatic analytical systems for residual agricultural chemicals) automatically performs extraction of pesticide residues from agricultural products with acetonitrile, filtration, constant volume, mixing with the use of air, mixing acetonitrile with buffer solven ... | 2014 | 25743385 |
| structural profiling and quantitation of glycosyl inositol phosphoceramides in plants with fourier transform mass spectrometry. | glycosyl inositol phosphoceramides (gipc) are the main sphingolipids in plants, and optimization of their extraction and detection is still in the focus of research. mass spectrometry provides new options for the analysis and structural elucidation of this complex class of lipids. the coupling of linear ion trap and orbitrap (ltq orbitrap) enabled various fragmentation experiments (ms(2), ms(3)) by collision-induced dissociation (cid) and pulsed-q dissociation (pqd). for structural analysis, gip ... | 2013 | 23573790 |
| optimization of a multi-residue screening method for the determination of 85 pesticides in selected food matrices by stir bar sorptive extraction and thermal desorption gc-ms. | a multi-residue method to determine 85 pesticides, including organochlorine pesticides, carbamates, organophosphorus pesticides, and pyrethroids, in vegetables, fruit, and green tea, has been developed. the method is based on stir bar sorptive extraction (sbse) coupled to thermal desorption (td) and retention time locked (rtl) gc-ms operating in the scan mode. samples are extracted with methanol and diluted with water prior to sbse. dilution of the methanol extract before sbse was optimized to o ... | 2005 | 16013835 |
| [method-performance studies of notified analytical method for fenbutatin oxide and cyhexatin]. | method-performance studies were conducted for the notified revised analytical method of fenbutatin oxide (fbto) and cyhexatin (cht). fbto and cht spiked into rice, soybeans, spinach, orange, tea powder and tea extract at the level of 0.5 microgram/g for fbto and 0.1 microgram/g for cht were analyzed in replicate in 6 laboratories. means recoveries of fbto were 85.2-96.5% and those of cht were 83.5-89.2% except from soybeans (46.5%). repeatability relative standard deviation values of fbto and ch ... | 2001 | 11577396 |
| influence of drought-induced water stress on soybean and spinach leaf ascorbate-dehydroascorbate level and redox status. | we examined the influence of water stress (water deficit) induced by drought on the steady state levels of ascorbic acid (asc), dehydroascorbate (dha), and the asc&rcolon;dha redox status in leaflets of glycine max (soybean) and leaves of spinacia oleracea (spinach). two soybean cultivars (cv. essex and cv. forrest) and one spinach cultivar (cv. nordic) were grown in high-light growth chambers ( approximately 1000-1200 µmol m-2 s-1) or in the greenhouse during may, june, and july 1999. the culti ... | 2000 | 10777451 |
| [a survey of radioactive levels of agricultural products in saitama prefecture]. | past atmospheric nuclear testing which have been conducted frequently, have caused environmental pollution due to the diffusion of radioactive substances into the atmosphere and from the radioactive fallout. the environmental pollution from nuclear testing into the atmosphere has resulted in the radioactive contamination in agricultural products and has continued for a long time. the radioactive contamination of agricultural products occurs through air, water and soil which were contaminated by ... | 1997 | 9423326 |
| molecular cloning and characterization of a cdna encoding putative phospholipid hydroperoxide glutathione peroxidase from spinach. | a cdna encoding spinach putative phospholipid hydroperoxide glutathione peroxidase (phgpx) was cloned and sequenced. the cdna included an open reading frame that encoded a polypeptide of 171 amino acid residues. the deduced amino acid sequence showed about 77 and 50% similarity to plant putative phgpxs and mammalian phgpxs, respectively. pcr product with the same size as that of the spinach putative phgpx were obtained from maize, soybeans, and arabidopsis, suggesting the expression of putative ... | 1997 | 9301122 |
| regulation of sucrose phosphate synthase by gibberellins in soybean and spinach plants. | exogenous applications of gibberellins (gas) increased the extractable activity of leaf sucrose phosphate synthase (sps) in soybean (glycine max [l.]) and spinach (spinacia oleracea [l.]). the response to ga applications was detectable within 2 h postapplication and was still observed 6 h, 24 h, and 7 d after treatment. when paclobutrazol, a ga biosynthesis inhibitor, was applied to intact soybean and spinach plants, decreased extractable sps activity resulted within 24 h following the treatment ... | 1992 | 16653111 |
| aspartic-acid synthesis in c3 plants. | in a previous study (melzer and o'leary, 1987, plant physiol. 84, 58-60), we used isotopic methods to show that a substantial fraction of protein-bound aspartic acid in tobacco is derived from anaplerotic synthesis via phosphoenolpyruvate (pep) carboxylase. similar studies in soybean (glycine max l.) and spinach (spinacia oleracea l.) showed a similar pattern, and this pattern persists with age because of slow protein turnover. a more quantitative analysis indicates that about 40% of protein-bou ... | 1991 | 24186420 |
| nitrite photoreduction in vivo is inhibited by oxygen. | it was hypothesized previously that an o(2) inhibition of no(2) (-) photoreduction would reflect a competition between o(2) and no(2) (-) for electrons from ferredoxin at the site of plastid nitrite reductase. in order to test this in vivo, intact spinach (spinacia oleracea l.) leaf chloroplast and mesophyll cell isolates held in high light were aerated with streams of 20% o(2)/80% n(2) (250 micromolar o(2) in aqueous solution) or, alternatively, streams of 100% n(2). bicarbonate plus co(2) and ... | 1990 | 16667362 |
| resolution of two molecular forms of sucrose-phosphate synthase from maize, soybean and spinach leaves. | two forms of sucrose-phosphate synthase (ec 2.4.1.14) were resolved from leaves of three species, maize (zea mays l. cv. pioneer 3184), soybean (glycine max (l.) merr., cv. ransom) and spinach (spinacia oleracea l. cv. resistoflay) by hydroxyapatite ultrogel chromatography, using a 75-mm (designated peak 1) and 250-mm (peak 2) k-phosphate discontinuous-gradient elution. rechromatography of the two forms showed that they were not readily interconvertible. the distribution of activity between the ... | 1987 | 24233014 |
| phosphoglycolate phosphatase: purification and preparation of antibodies. | phosphoglycolate phosphatase was partially purified from leaves of nicotiana rustica using ion exchange and chromatofocusing columns. the native molecular weight of the enzyme was determined to be about 58 kd from ferguson plots, with a subunit size of about 32 kd. the native enzyme is thus likely to be a dimer. a polyclonal antibody prepared against the lds denatured enzyme cross reacted with proteins from nicotiana tabacum, glycine max, spinacea oleracea and arabidopsis thaniana. there was lit ... | 1987 | 24430563 |
| the relationship between phosphate status and photosynthesis in leaves : effects on intracellular orthophosphate distribution, photosynthesis and assimilate partitioning. | photosynthesis, assimilate partitioning and intracellular distribution of orthophosphate (pi) in barly (hordeum vulgare l.) leaves were measured in plants grown with either 25, 1 or 0 mmol· 1(-1) nutrient phosphate supply. phosphate deficiency resulted in a significant decrease in the leaf pi, diminished rates of photosynthesis and a decrease in the sucrose/starch ratio in the leaves. changes in the cytoplasmic pi content were relatively small in comparison with the large variations in vacuolar ... | 1986 | 24240306 |
| localization of carbamoylphosphate synthetase and aspartate carbamoyltransferase in chloroplasts. | the localization of carbamoylphosphate synthetase (cpsase) and aspartate carbamoyltransferase (actase), the first two enzymes of the pyrimidine biosynthetic pathway, in chloroplasts was investigated. in dark-grown radish (raphanus sativus) seedlings, light induced a prominent increase in cpsase activity, but had little effect on actase activity. both enzymes were found in chloroplasts isolated from radish cotyledons and leaves of spinach (spinacia oleracea), soybean (glycine max), and corn (zea ... | 1986 | 16664566 |
| lipid molecular species composition of thylakoid membranes. | lipid molecular species compositions of chloroplast thylakoid membranes of mesophyll cells from spinacia oleracea, glycine max, oryza sativa and zea mays and of bundle sheath cells from zea mays have been quantitatively determined. no significant difference in the lipid molecular species composition was found among the five membrane sources. the predominant molecular species of monogalactosyldiacylglycerol was the 1-linolenoyl parallel to 2-linolenoyl species. the 1-linolenoyl parallel to 2-lino ... | 1980 | 7188732 |
| effect of certain home practices on reduced ascorbic acid content of peas, rhubarb, snap beans, soybeans, and spinach. | | 2016 | 18897319 |
| involvement of extracellular cu/zn superoxide dismutase in cotton fiber primary and secondary cell wall biosynthesis. | extracellular cu/zn superoxide dismutases (csds) that catalyze the conversion of superoxide to hydrogen peroxide have been suggested to be involved in lignification of secondary walls in spinach, pine and aspen. in cotton fibers, hydrogen peroxide was proposed to be involved in the induction of secondary cell wall biosynthesis. recently, we identified extracellular csds from developing cotton fibers using both immunological and epitope tagging techniques. since cotton fibers are not lignified, w ... | 2008 | 19704453 |
| transgenic cotton over-producing spinach sucrose phosphate synthase showed enhanced leaf sucrose synthesis and improved fiber quality under controlled environmental conditions. | prior data indicated that enhanced availability of sucrose, a major product of photosynthesis in source leaves and the carbon source for secondary wall cellulose synthesis in fiber sinks, might improve fiber quality under abiotic stress conditions. to test this hypothesis, a family of transgenic cotton plants (gossypium hirsutum cv. coker 312 elite) was produced that over-expressed spinach sucrose-phosphate synthase (sps) because of its role in regulation of sucrose synthesis in photosynthetic a ... | 2007 | 17287885 |
| initiation and characterization of a cotton (gossypium hirsutum l.) photoautotrophic cell suspension culture. | a heterotrophic cotton (gossypium hirsutum l. cv. stoneville 825) cell suspension culture was adapted to grow photoautotrophically. after two years in continuous photoautotrophic culture at 5% co2 (balance air), the maximum growth rate of the photoautotrophic cell line was a 400% fresh weight increase in eight days. the chl concentration was approximately 500 μg per g fresh weight.elevated co2 (1%-5%) was required for culture growth, while the ambient air of the culture room (600 to 700 ul co2 1 ... | 1988 | 24241763 |
| differences in internalization and growth of escherichia coli o157:h7 within the apoplast of edible plants, spinach and lettuce, compared with the model species nicotiana benthamiana. | internalization of food-borne bacteria into edible parts of fresh produce plants represents a serious health risk. therefore, internalization of verocytotoxigenic e. coli o157:h7 isolate sakai was assessed in two species associated with outbreaks, spinach (spinacia oleracea) and lettuce (lactuca sativa) and compared to the model species nicotiana benthamiana. internalization occurred in the leaves and roots of spinach and lettuce throughout a 10 day time-course. the plant species, tissue type an ... | 2017 | 28169510 |
| absence of internalization of escherichia coli o157:h7 into germinating tissue of field-grown leafy greens. | both growth chamber and field studies were conducted to investigate the potential for escherichia coli o157:h7 to be internalized into leafy green tissue when seeds were germinated in contaminated soil. internalized e. coli o157:h7 was detected by enrichment in both spinach (spinacia oleracea l.) and lettuce (lactuca sativa l.) seedlings when seeds were germinated within the growth chamber in autoclaved and nonautoclaved soil, respectively, contaminated with e. coli o157:h7 at 2.0 and 3.8 log cf ... | 2014 | 24490912 |
| photobleaching with phloxine b sensitizer to reduce food matrix interference for detection of escherichia coli serotype o157:h7 in fresh spinach by flow cytometry. | a flow cytometric method (rapid-b™) with detection sensitivity of one viable cell of escherichia coli serotype o157:h7 in fresh spinach (spinacia oleracea) was developed and evaluated. the major impediment to achieving this performance was mistaking autofluorescing spinach particles for tagged target cells. following a 5 h non-selective enrichment, artificially inoculated samples were photobleached, using phloxine b as a photosensitizer. samples were centrifuged at high speed to concentrate targ ... | 2013 | 24010624 |
| effects of medicinal plant extracts and photosensitization on aflatoxin producing aspergillus flavus (raper and fennell). | this study was undertaken with an aim of exploring the effectiveness of medicinal plant extracts in the control of aflatoxin production. antifungal properties, photosensitization, and phytochemical composition of aqueous and organic extracts of fruits from solanum aculeastrum, bark from syzygium cordatum, and leaves from prunus africana, ocimum lamiifolium, lippia kituiensis, and spinacia oleracea were tested. spores from four-day-old cultures of previously identified toxigenic fungi, uonv017 an ... | 2017 | 28539938 |
| influence of bio-fertilizer containing beneficial fungi and rhizospheric bacteria on health promoting compounds and antioxidant activity of spinacia oleracea l. | this study evaluates the influences of bio fertilizers containing mycorrhizal fungi (glomus fasciculatum, glomus mosseae) individually or in combination with n-fixer (azotobacter chroococcum), k solubilizer (bacillus mucilaginous) and p solubilizer (bacillus megaterium) on soil fertility and phytochemical levels of spinach. | 2017 | 28815474 |
| evaluation of the antimicrobial activities of ultrasonicated spinach leaf extracts using rapd markers and electron microscopy. | spinach (spinacia oleracea l.) leaves represent an important dietary source of nutrients, antioxidants and antimicrobials. as such, spinach leaves play an important role in health and have been used in the treatment of human diseases since ancient times. here, the aims were to optimize the extraction methods for recovering antimicrobial substances of spinach leaves, determine the minimum inhibitory concentrations (mics) of the antimicrobial substances against escherichia coli and staphylococcus ... | 2017 | 28766036 |
| the broad spectrum 2-oxoglutarate oxygenase inhibitor n-oxalylglycine is present in rhubarb and spinach leaves. | 2-oxoglutarate (2og) and ferrous iron dependent oxygenases are involved in many biological processes in organisms ranging from humans (where some are therapeutic targets) to plants. these enzymes are of significant biomedicinal interest because of their roles in hypoxic signaling and epigenetic regulation. synthetic n-oxalylglycine (nog) has been identified as a broad-spectrum 2og oxygenase inhibitor and is currently widely used in studies on the hypoxic response and chromatin modifications in a ... | 2015 | 26196940 |
| genome sequences of spinach deltapartitivirus 1, spinach amalgavirus 1, and spinach latent virus identified in spinach transcriptome. | complete genome sequences of three new plant rna viruses, spinach deltapartitivirus 1 (spdpv1), spinach amalgavirus 1 (spav1), and spinach latent virus (splv), were identified from a spinach (spinacia oleracea) transcriptome dataset. the rna-dependent rna polymerases (rdrps) of spdpv1, spav1, and splv showed 72%, 53%, and 93% amino acid sequence identities with the homologous rdrp of the most closely related virus, respectively, suggesting that spdpv1 and spav1 were novel viruses. sequence simil ... | 2017 | 28511294 |
| folate biofortification in hydroponically cultivated spinach by the addition of phenylalanine. | folate is an important vitamin mainly ingested from vegetables, and folate deficiency causes various health problems. recently, several studies demonstrated folate biofortification in plants or food crops by metabolic engineering through genetic modifications. however, the production and sales of genetically modified foods are under strict regulation. here, we developed a new approach to achieve folate biofortification in spinach (spinacia oleracea) without genetic modification. we hydroponicall ... | 0 | 28548831 |
| influence of groundwater and wastewater irrigation on lead accumulation in soil and vegetables: implications for health risk assessment and phytoremediation. | the current study evaluated the effect of groundwater and wastewater irrigation on lead (pb) accumulation in soil and vegetables, and its associated health implications. a pot experiment was conducted in which spinach (spinacia oleracea), radish (raphanus sativus) and cauliflower (brassica oleracea) were irrigated with groundwater and wastewaters containing varying concentrations of pb. lead contents were measured in wastewaters, soils and root and shoot of vegetables. we also measured health ri ... | 0 | 28463566 |
| appetite suppressing effect of spinacia oleracea in rats: involvement of the short term satiety signal cholecystokinin. | spinacia oleracea (spinach) is a green leafy vegetable rich in antioxidant phyto-constituents such as flavonoids, polyphenols, carotenoids and vitamins. fruits and vegetables rich in flavonoids are known to prevent weight gain by inducing satiety. the present study evaluates the appetite suppressing effect of a flavonoid rich extract of the spinach leaf (soe) in rats. hptlc of soe was performed for detecting flavonoids. rats were administered soe (200 mg/kg and 400 mg/kg, p. o) and fluoxetine (6 ... | 0 | 28238891 |
| functional properties of spinach (spinacia oleracea l.) phytochemicals and bioactives. | overwhelming evidence indicates that diets rich in fruits and vegetables are protective against common chronic diseases, such as cancer, obesity and cardiovascular disease. leafy green vegetables, in particular, are recognized as having substantial health-promoting activities that are attributed to the functional properties of their nutrients and non-essential chemical compounds. spinach (spinacia oleracea l.) is widely regarded as a functional food due to its diverse nutritional composition, wh ... | 0 | 27353735 |
| biochar enhances the cadmium tolerance in spinach (spinacia oleracea) through modification of cd uptake and physiological and biochemical attributes. | cadmium (cd) has no known role in plant biology and is toxic to plants and animals. the cd mainly accumulated in agricultural soils through anthropogenic activities, such as sewage water irrigation and phosphorus fertilization. biochar (bc) has been proposed as an amendment to reduce metal toxicity in plants. the objective of this study was to evaluate the role of bc (cotton stick at a rate of 0, 3, and 5 %) on cd uptake and the photosynthetic, physiological, and biochemical responses of spinach ... | 0 | 27502564 |
| assessment of different washing treatments to mitigate imidacloprid and acetamaprid residues in spinach. | agricultural crops treated with pesticides retain toxic residues that can cause various health disorders upon consumption. the present research project was designed to assess pesticide residues in contaminated spinach (spinacia oleracea). the efficiency of chemical solutions (acetic acid, citric acid, hydrogen peroxide, sodium chloride and sodium carbonate) of different concentrations (% w/v) along with tap water for the dissolution of pesticide residues in spinach was studied. after various dip ... | 0 | 26678536 |
| assessment of fertilizer potential of the struvite produced from the treatment of methanogenic landfill leachate using low-cost reagents. | leachates generated in methanogenic landfills contain high strength of ammonium nitrogen which removal is hard to be accomplished by means of conventional techniques. the chemical precipitation of struvite, which is a mineral that could be reused as a slow-release fertilizer, is an effective process in the removal and recovery of nh4 amount of high-concentrated wastewaters. in this paper, a struvite precipitation process using unconventional reagents is proposed for a sustainable recovery of nit ... | 0 | 26604197 |
| ammonium reduces oxalate accumulation in different spinach (spinacia oleracea l.) genotypes by inhibiting root uptake of nitrate. | excessive accumulation of oxalate negatively affects nutritional value of many vegetables, such as spinach (spinacia oleracea l.). mixed solution of ammonium and nitrate could effectively reduce oxalate accumulation, while the mechanism involved remains unknown. high (heizhenzhu) and low (weilv) oxalate-accumulated spinach genotypes were used in this study to investigate the association of oxalate accumulation and root uptake of nitrogen. exposure of increasing nitrate or mixed-nitrogen (nitrate ... | 0 | 25976827 |
| colonization of spinach by verticillium dahliae and effects of pathogen localization on the efficacy of seed treatments. | verticillium wilt on spinach (spinacia oleracea) is caused by the soilborne fungus verticillium dahliae. the pathogen is seedborne and transmission through seed is a major concern because of the dispersal of the pathogen to areas where fresh and processing spinach crops are grown in rotation with susceptible crops. reduction in seedborne inoculum minimizes pathogen spread; therefore, knowledge of pathogen localization in seed is critical to develop methods to reduce seedborne inoculum. spinach s ... | 2013 | 23190117 |
| defining the far-red limit of photosystem ii in spinach. | the far-red limit of photosystem ii (psii) photochemistry was studied in psii-enriched membranes and psii core preparations from spinach (spinacia oleracea) after application of laser flashes between 730 and 820 nm. light up to 800 nm was found to drive psii activity in both acceptor side reduction and oxidation of the water-oxidizing camn(4) cluster. far-red illumination induced enhancement of, and slowed down decay kinetics of, variable fluorescence. both effects reflect reduction of the accep ... | 2009 | 19700631 |
| ent-kaurene biosynthesis is enhanced by long photoperiods in the long-day plants spinacia oleracea l. and agrostemma githago l. | the effect of photoperiod on ent-kaurene biosynthesis was determined in the long-day (ld) plants spinach (spinacia oleracea l.) and agrostemma githago l. further metabolism of ent-kaurene was blocked by application of the growth retardant tetcyclacis, and ent-kaurene accumulation was measured by isotopic dilution using gas chromatography-selected ion monitoring (gc-sim) (e. grosselindemann, j.e. graebe, d. stöckl, p. hedden [1991] plant physiol 96: 1099-1104). in spinach, the rate of ent-kaurene ... | 1993 | 8278497 |
| draft genome of spinach and transcriptome diversity of 120 spinacia accessions. | spinach is an important leafy vegetable enriched with multiple necessary nutrients. here we report the draft genome sequence of spinach (spinacia oleracea, 2n=12), which contains 25,495 protein-coding genes. the spinach genome is highly repetitive with 74.4% of its content in the form of transposable elements. no recent whole genome duplication events are observed in spinach. genome syntenic analysis between spinach and sugar beet suggests substantial inter- and intra-chromosome rearrangements d ... | 2017 | 28537264 |
| intracellular location of carbonate dehydratase (carbonic anhydrase) in leaf tissue. | two proteins which have carbonate dehydratase (carbonic anhydrase, ec 4.2.1.1) activity were shown to be in the chloroplasts and in the cytosol of leaves of brassica chinensis, spinacia oleracea, and in variegated leaves of tradescantia albiflora and hedera canariensis. the chloroplastic enzyme is smaller than the one in the cytosol, as it runs farther on gradient polyacrylamide gels. it was separated from the other by isolation of chloroplasts of brassica and spinacia on sucrose density gradien ... | 1979 | 16660683 |
| evaluation of leafy vegetables as bioindicators of gaseous mercury pollution in sewage-irrigated areas. | mercury (hg) can evaporate and enter the plants through the stomata of plant leaves, which will cause a serious threat to local food safety and human health. for the risk assessment, this study aimed to investigate the concentration and accumulation of total gaseous mercury (tgm) in five typical leafy vegetables (chinese chives (allium tuberosum rottler), amaranth (amaranthus mangostanus l.), rape (brassica campestris l.), lettuce (lactuca sativa l.), and spinach (spinacia oleracea l.)) grown on ... | 2018 | 29043585 |
| development of a sensitive monoclonal antibody-based indirect competitive enzyme-linked immunosorbent assay for analysing chlorantraniliprole residues. | chlorantraniliprole (cap) is a new anthranilic diamide insecticide acting with high efficacy on ryanodine receptors of most of the species within the lepidoptera order and has been used worldwide. to monitor its residue in food and environmental samples, we developed an indirect competitive enzyme-linked immunosorbent assay (icelisa), based on monoclonal antibodies. the established icelisa possesses a concentration of producing 50% inhibition (ic50) of 1.60ng/ml. in addition, the assay had the a ... | 2014 | 24054242 |
| consumers' acceptance of medicinal herbs: an application of the technology acceptance model (tam). | the shift in consumers' preferences from synthetic to 'natural' products has led to a resurgence of interest in medicinal plants, particularly in developing countries. however, research data about consumers' preferences for particular products is hard to find. | 2017 | 28625892 |
| inhibition of photosynthesis and respiration by batatasins. | effects of batatasins i, iii and v, phenolic growth inhibitors occuring in dormant bulbils of dioscorea batatas decne., on photosynthetic reactions of chloroplasts from spinach (spinacia oleracea l.) and on respiration of mitochondria from potatoes (solanum tuberosum l.) were investigated. in chloroplasts, the batatasins effectively inhibited co2-dependent oxygen evolution and electron flow from water to acceptors such as dichlorophenolindophenol, ferricyanide and methylviologen. photosystem-i d ... | 1978 | 24414012 |
| regulation of nitric oxide (no) production by plant nitrate reductase in vivo and in vitro. | no (nitric oxide) production from sunflower plants (helianthus annuus l.), detached spinach leaves (spinacia oleracea l.), desalted spinach leaf extracts or commercial maize (zea mays l.) leaf nitrate reductase (nr, ec 1.6.6.1) was continuously followed as no emission into the gas phase by chemiluminescence detection, and its response to post-translational nr modulation was examined in vitro and in vivo. nr (purified or in crude extracts) in vitro produced no at saturating nadh and nitrite conce ... | 2002 | 11741046 |
| evidence that ribulose 1,5-bisphosphate (rubp) binds to inactive sites of rubp carboxylase in vivo and an estimate of the rate constant for dissociation. | the binding of ribulose 1,5-bisphosphate (rubp) to inactive (noncarbamylated) sites of the enzyme rubp carboxylase in vivo was investigated in spinacia oleracea and helianthus annuus. the concentrations of rubp and inactive sites were determined in leaf tissue as a function of time after a change to darkness. rubp concentrations fell rapidly after the change to darkness and were approximately equal to the concentration of inactive sites after 60 s. variations in the concentration of inactive sit ... | 1989 | 16666692 |
| fixation of o(2) during photorespiration: kinetic and steady-state studies of the photorespiratory carbon oxidation cycle with intact leaves and isolated chloroplasts of c(3) plants. | mass spectrometric techniques were used to trace the incorporation of [(18)o]oxygen into metabolites of the photorespiratory pathway. glycolate, glycine, and serine extracted from leaves of the c(3) plants, spinacia oleracea l., atriplex hastata, and helianthus annuus which had been exposed to [(18)o]oxygen at the co(2) compensation point were heavily labeled with (18)o. in each case one, and only one of the carboxyl oxygens was labeled. the abundance of (18)o in this oxygen of glycolate reached ... | 1978 | 16660647 |
| lipid and fatty acid composition of chloroplast envelope membranes from species with differing net photosynthesis. | lipid and fatty acid compositions were determined for chloroplast envelope membranes isolated from spinach (spinacia oleracea l.), sunflower (helianthus annuus l.), and maize (zea mays l.) leaves. the lipid composition was similar in sunflower, spinach, and undifferentiated maize chloroplast envelope membranes and different in maize mesophyll chloroplast envelope membranes. the predominant lipid constituents in all envelope membranes were monogalactosyldiglyceride (27 to 46%), digalactosyldiglyc ... | 1976 | 16659725 |
| isolation and bicarbonate transport of chloroplast envelope membranes from species of differing net photosynthetic efficiency. | a three-phase discontinuous sucrose gradient yielded two fractions of chloroplast envelope membranes from spinach (spinacia oleracea l.), sunflower (helianthus annuus l.), and maize (zea mays l., mesophyll and undifferentiated chloroplasts). these species were selected to represent plants with fast photorespiration and slow net photosynthesis, fast photorespiration yet fast net photosynthesis, and slow photorespiration and fast net photosynthesis, respectively. buoyant densities were 1.08 and 1. ... | 1976 | 16659477 |
| distribution of protein-bound hexosamine in chloroplasts. | intact chloroplasts of spinach (spinacia oleracea l.), sunflower (helianthus annuus l.), and maize (zea mays l.) mesophyll cells contained 0.33, 0.50, and 0.14% of bound hexosamine on a protein basis, respectively. undifferentiated maize chloroplasts contained 0.19%. values for chloroplast lamellae were, respectively, 0.16, 0.18, 0.12, and 0.06% and for envelope membranes they were 1.6, 2.5, 3.8, and 2.7%. thus most of the hexosamine of chloroplasts is located in the envelope membrane. | 1976 | 16659424 |
| [rhizosphere products of helianthus annuus and spinacia oleracea]. | | 1967 | 5584637 |
| the hevea brasiliensis xip aquaporin subfamily: genomic, structural and functional characterizations with relevance to intensive latex harvesting. | x-intrinsic proteins (xip) were recently identified in a narrow range of plants as a full clade within the aquaporins. these channels reportedly facilitate the transport of a wide range of hydrophobic solutes. the functional roles of xip in planta remain poorly identified. in this study, we found three xip genes (hbxip1;1, hbxip2;1 and hbxip3;1) in the hevea brasiliensis genome. comprehensive bioinformatics, biochemical and structural analyses were used to acquire a better understanding of this ... | 2016 | 27068521 |
| improved tolerance to various abiotic stresses in transgenic sweet potato (ipomoea batatas) expressing spinach betaine aldehyde dehydrogenase. | abiotic stresses are critical delimiters for the increased productivity and cultivation expansion of sweet potato (ipomoea batatas), a root crop with worldwide importance. the increased production of glycine betaine (gb) improves plant tolerance to various abiotic stresses without strong phenotypic changes, providing a feasible approach to improve stable yield production under unfavorable conditions. the gene encoding betaine aldehyde dehydrogenase (badh) is involved in the biosynthesis of gb in ... | 2012 | 22615986 |
| accumulation of heavy metals from contaminated soil to plants and evaluation of soil remediation by vermiculite. | we evaluated the distribution of 15 metal ions, namely al, cd, cu, cr, fe, la, mn, ni, pb, sc, ti, v, y, zn and zr, in the soil of a contaminated site in piedmont (italy). this area was found to be heavily contaminated with cu, cr and ni. the availability of these metal ions was studied using tessier's sequential extraction procedure: the fraction of mobile species, which potentially is the most harmful for the environment, was much higher than that normally present in unpolluted soils. this soi ... | 2011 | 21055788 |
| metabolic fate of [14c] chlorophenols in radish (raphanus sativus), lettuce (lactuca sativa), and spinach (spinacia oleracea). | chlorophenols are potentially harmful pollutants that are found in numerous natural and agricultural systems. plants are a sink for xenobiotics, which occur either intentionally or not, as they are unable to eliminate them although they generally metabolize them into less toxic compounds. the metabolic fate of [ (14)c] 4-chlorophenol (4-cp), [ (14)c] 2,4-dichlorophenol (2,4-dcp), and [ (14)c] 2,4,5-trichlorophenol (2,4,5-tcp) was investigated in lettuce, spinach, and radish to locate putative to ... | 2008 | 18763782 |
| how does glutamine synthetase activity determine plant tolerance to ammonium? | the wide range of plant responses to ammonium nutrition can be used to study the way ammonium interferes with plant metabolism and to assess some characteristics related with ammonium tolerance by plants. in this work we investigated the hypothesis of plant tolerance to ammonium being related with the plants' capacity to maintain high levels of inorganic nitrogen assimilation in the roots. plants of several species (spinacia oleracea l., lycopersicon esculentum l., lactuca sativa l., pisum sativ ... | 2006 | 16292661 |
| improving spinach, radish, and lettuce growth under red light-emitting diodes (leds) with blue light supplementation. | radish (raphanus sativus l. cv. cherriette), lettuce (lactuca sativa l. cv. waldmann's green), and spinach (spinacea oleracea l. cv. nordic iv) plants were grown under 660-nm red light-emitting diodes (leds) and were compared at equal photosynthetic photon flux (ppf) with either plants grown under cool-white fluorescent lamps (cwf) or red leds supplemented with 10% (30 micromoles m-2 s-1) blue light (400-500 nm) from blue fluorescent (bf) lamps. at 21 days after planting (dap), leaf photosynthet ... | 2001 | 12542027 |
| transfer of the fungicide vinclozolin from treated to untreated plants via volatilization. | head lettuce plantlets (lactuca sativa l. var. capitata) were potted, treated with vinclozolin at the six-leaf stage according to application standards and allowed to dry for 24 h. the potted plantlets were then placed in either growth chambers with controlled temperature (20 and 25 degrees c, respectively) or in a greenhouse (approximately 12 degrees c), together with untreated spinach (spinacia oleracea l.) and standardized grass cultures (lolium multiflorum lam. ssp.) while the treated lettuc ... | 2002 | 12137060 |
| the interrelationship between the lower oxygen limit, chlorophyll fluorescence and the xanthophyll cycle in plants. | the lower oxygen limit (lol) in plants may be identified through the measure of respiratory gases [i.e. the anaerobic compensation point (acp) or the respiratory quotient breakpoint (rqb)], but recent work shows it may also be identified by a sudden rise in dark minimum fluorescence (f(o)). the interrelationship between aerobic respiration and fermentative metabolism, which occur in the mitochondria and cytosol, respectively, and fluorescence, which emanates from the chloroplasts, is not well do ... | 2011 | 21290261 |
| a new room temperature gas sensor based on pigment-sensitized tio2 thin film for amines determination. | a new room temperature gas sensor was fabricated with pigment-sensitized tio2 thin film as the sensing layer. four natural pigments were extracted from spinach (spinacia oleracea), red radish (raphanus sativus l), winter jasmine (jasminum nudiflorum), and black rice (oryza sativa l. indica) by ethanol. natural pigment-sensitized tio2 sensor was prepared by immersing porous tio2 films in an ethanol solution containing a natural pigment for 24h. the hybrid organic-inorganic formed films here were ... | 2015 | 24934102 |
| determination of pork spoilage by colorimetric gas sensor array based on natural pigments. | a new colorimetric gas-sensor array based on four natural pigments, that were extracted from spinach (spinacia oleracea), red radish (raphanus sativus l.), winter jasmine (jasminum nudiflorum), and black rice (oryza sativa l. indica), was developed for pork freshness evaluation. a colour change profile for each sample was obtained by differentiating the images of the sensor array before and after exposure to the odour of sample. the total viable count (tvc) per gram of pork was obtained by class ... | 2014 | 24128513 |
| isolation of thylakoid membrane complexes from rice by a new double-strips bn/sds-page and bioinformatics prediction of stromal ridge subunits interaction. | thylakoid membrane complexes of rice (oryza sativa l.) play crucial roles in growth and crop production. understanding of protein interactions within the complex would provide new insights into photosynthesis. here, a new "double-strips bn/sds-page" method was employed to separate thylakoid membrane complexes in order to increase the protein abundance on 2d-gels and to facilitate the identification of hydrophobic transmembrane proteins. a total of 58 protein spots could be observed and subunit c ... | 2011 | 21637806 |
| bioaccumulation of heavy metals and two organochlorine pesticides (ddt and bhc) in crops irrigated with secondary treated waste water. | four crop plants oryza sativa (rice), solanum melongena (brinjal), spinacea oleracea (spinach) and raphanus sativus (radish) were grown to study the impact of secondary treated municipal waste water irrigation. these plants were grown in three plots each of 0.5 ha, and irrigated with secondary treated waste water from a sewage treatment plant. sludge from the same sewage treatment plant was applied as manure. cultivated plants were analyzed for accumulation of heavy metals and pesticides. result ... | 2009 | 18654831 |
| functional defect at the rice choline monooxygenase locus from an unusual post-transcriptional processing is associated with the sequence elements of short-direct repeats. | glycine betaine (gb), a quaternary ammonium solute, plays a crucial role in developing osmotic tolerance. rice contains a choline monooxygenase (cmo) and two betaine aldehyde dehydrogenase homologues that are required for gb synthesis, but usually no gb is accumulated in rice (oryza sativa). to elucidate the molecular processes that underlie the gb deficiency in rice, an experiment involving rice and spinach (spinacia oleracea) was conducted to analyze the products transcribed from cmo genes. re ... | 2007 | 17635219 |
| physical and kinetic evidence for an association between sucrose-phosphate synthase and sucrose-phosphate phosphatase. | the possible formation of a multienzyme complex between sucrose (suc)-phosphate synthase (sps) and suc-phosphate phosphatase (spp) was examined by measuring the rates of suc-6-phosphate (suc-6-p) synthesis and hydrolysis in mixing experiments with partially purified enzymes from spinach (spinacia oleracea) and rice (oryza sativa) leaves. the addition of spp to sps stimulated the rate of suc-6-p synthesis. sps inhibited the hydrolysis of exogenous suc-6-p by spp when added in the absence of its s ... | 1997 | 12223802 |
| pyruvate,orthophosphate dikinase in leaves and chloroplasts of c(3) plants undergoes light-/dark-induced reversible phosphorylation. | pyruvate,orthophosphate (pi) dikinase (ppdk) is best recognized as a chloroplastic c(4) cycle enzyme. as one of the key regulatory foci for controlling flux through this photosynthetic pathway, it is strictly and reversibly regulated by light. this light/dark modulation is mediated by reversible phosphorylation of a conserved threonine residue in the active-site domain by the ppdk regulatory protein (rp), a bifunctional protein kinase/phosphatase. ppdk is also present in c(3) plants, although it ... | 2002 | 11950985 |
| distinctive responses of ribulose-1,5-bisphosphate carboxylase and carbonic anhydrase in wheat leaves to nitrogen nutrition and their possible relationships to co(2)-transfer resistance. | the amounts of ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco), total chlorophyll (chl), and total leaf nitrogen were measured in fully expanded, young leaves of wheat (triticum aestivum l.), rice (oryza sativa l.), spinach (spinacia oleracea l.), bean (phaseolus vulgaris l.), and pea (pisum sativum l.). in addition, the activities of whole-chain electron transport and carbonic anhydrase were measured. all plants were grown hydroponically at different nitrogen concentrations. although ... | 1992 | 16653191 |
| effect of fusicoccin on plant cell cultures and protoplasts. | we have assayed the capacity of the fungal toxin fusicoccin to induce some of its characteristic effects (acidification of the medium, stimulation of k(+), and of 3-o-methyl-d-glucose uptake) in cell suspensions of parthenocissus tricuspidata (siebold et zucc.) planchon, acer pseudoplatanus l. and oryza sativa l., and in protoplast suspensions prepared from leaves of nicotiana tabacum l. and spinacia oleracea l. or from cultures of p. tricuspidata. evidence is presented showing that all tested b ... | 1977 | 24420024 |
| the biosynthesis of steryl glucosides in plants. | mitochondrial preparations from pea root (pisum sativum l. var. alaska) cauliflower inflorescence (brassica cauliflora gars.) and avocado inner mesocarp (persea americana mill. var. fuerte), and chloroplast preparations from spinach leaf (spinacia oleracea l. var. bloomsdale) incorporate glucose into steryl glucoside and acylated steryl glucoside when either uridine diphosphate-glucose or uridine diphosphate-galactose is supplied as precursor. in the case of pea root mitochondria, galactosyl dig ... | 1970 | 5423466 |
| unambiguous regiochemical assignment of sulfoquinovosyl mono- and diacylglycerols in parsley and spinach leaves by liquid chromatography/electrospray ionization sequential mass spectrometry assisted by regioselective enzymatic hydrolysis. | sulfoquinovosylmonoglycerides (sqmg) and sulfoquinovosyldiglycerides (sqdg) in the lipid extracts of parsley (petroselinum crispum) and spinach (spinacia oleracea) leaves were investigated. the aim of this work was to assess and establish the chemical characterization of fatty acyl chains in sulfolipids (sqmg and sqdg) and their regiochemistry. | 2017 | 28657161 |
| heterogenous stomatal closure in response to leaf water deficits is not a universal phenomenon. | the extent and occurrence of water stress-induced "patchy" co(2) uptake across the surface of leaves was evaluated in a number of plant species. leaves, while still attached to a plant, were illuminated and exposed to air containing [(14)c]co(2) before autoradiographs were developed. plant water deficits that caused leaf water potential depression to -1.1 megapascals during a 4-day period did result in heterogenous co(2) assimilation patterns in bean (phaseolus vulgaris). however, when the same ... | 1992 | 16668692 |
| d-glucosone and l-sorbosone, putative intermediates of l-ascorbic acid biosynthesis in detached bean and spinach leaves. | d-[6-(14)c]glucosone that had been prepared enzymically from d-[6-(14)c]glucose was used to compare relative efficiencies of these two sugars for l-ascorbic acid (aa) biosynthesis in detached bean (phaseolus vulgaris l., cv california small white) apices and 4-week-old spinach (spinacia oleracea l., cv giant noble) leaves. at tracer concentration, (14)c from glucosone was utilized by spinach leaves for aa biosynthesis much more effectively than glucose. carbon-14 from [6-(14)c]glucose underwent ... | 1990 | 16667861 |
| conversion of l-sorbosone to l-ascorbic acid by a nadp-dependent dehydrogenase in bean and spinach leaf. | an nadp-dependent dehydrogenase catalyzing the conversion of l-sorbosone to l-ascorbic acid has been isolated from phaseolus vulgaris l. and spinacia oleracea l. and partially purified. it is stable at -20 degrees c for up to 8 months. molecular masses, as determined by gel filtration, were 21 and 29 kilodaltons for bean and spinach enzymes, respectively. k(m) for sorbosone were 12 +/- 2 and 18 +/- 2 millimolar and for nadp(+), 0.14 +/- 0.05 and 1.2 +/- 0.5 millimolar, for bean and spinach, resp ... | 1990 | 16667860 |
| activity ratios of ribulose-1,5-bisphosphate carboxylase accurately reflect carbamylation ratios. | activity ratios and carbamylation ratios of ribulose-1,5-bisphosphate carboxylase (rubpcase) were determined for leaves of phaseolus vulgaris and spinacia oleracea exposed to a variety of partial pressures of co(2) and o(2) and photon flux densities (pfd). it was found that activity ratios accurately predicted carbamylation ratios except in extracts from leaves held in low pfd. in particular, it was confirmed that the loss of rubpcase activity in low partial pressure of o(2) and high pfd results ... | 1989 | 16666614 |
| effect of temperature on electron transport activities of isolated chloroplasts. | temperature-induced changes in electron transport activities of chloroplasts isolated from chilling-sensitive and chilling-resistant plants have been examined. using methylviologen as electron acceptor, temperature-induced changes occurred in the photosystem ii plus photosystem i activities of chloroplasts isolated from chilling-resistant spinach (spinacia oleracea l.) and pea (pisum sativum l. cv. alaska) plants. the changes occurred at approximately 17 c for spinach and 15 c for pea. a tempera ... | 1980 | 16661411 |
| qualitative and quantitative immunofluorescence studies of chloroplast ferredoxin : application to investigations of ferredoxin inheritance in nicotiana hybrids. | antibodies were raised in rabbits against 2fe-2s ferredoxin from n. tabacum l. the antibodies showed partial cross-reactivity in the double diffusion test with ferredoxins from spinacia oleracea l., petunia inflata fries., p. axillaris lam., phaseolus vulgaris l., chlamydomonas remhardii dang. a complete cross-reaction was observed with ferredoxins from five other nicotiana species, thus with this test it was impossible to discriminate between these ferredoxins. therefore the following test was ... | 1977 | 24420666 |
| temperature dependence of the permeability of chloroplasts from chilling-sensitive and chilling-resistant plants. | osmotic responses of chloroplasts from chilling-resistant (pisum sativum l., spinacia oleracea l.) and chilling-sensitive (phaseolus vulgaris l., lycopersicon esculentum mill.) plants to glycerol and erythritol were determined from 1° to 28°. the permeability of the chloroplast limiting membranes, as measured by reflection coefficients, decreased when the temperature was raised. for pisum and spinacia the curves relating reflection coefficients and temperature were smooth, while for phaseolus an ... | 1974 | 24458931 |
| the physiological implications of urease inhibitors on n metabolism during germination of pisum sativum and spinacea oleracea seeds. | the development of new nitrogen fertilizers is necessary to optimize crop production whilst improving the environmental aspects arising from the use of nitrogenous fertilization as a cultural practice. the use of urease inhibitors aims to improve the efficiency of urea as a nitrogen fertilizer by preventing its loss from the soil as ammonia. however, although the action of urease inhibitors is aimed at the urease activity in soil, their availability for the plant may affect its urease activity. ... | 2012 | 22405591 |
| short term physiological implications of nbpt application on the n metabolism of pisum sativum and spinacea oleracea. | the application of urease inhibitors in conjunction with urea fertilizers as a means of reducing n loss due to ammonia volatilization requires an in-depth study of the physiological effects of these inhibitors on plants. the aim of this study was to determine how the urease inhibitor n-(n-butyl) thiophosphoric triamide (nbpt) affects n metabolism in pea and spinach. plants were cultivated in pure hydroponic culture with urea as the sole n source. after 2 weeks of growth for pea, and 3 weeks for ... | 2011 | 20932600 |
| effects of copper on the photosynthesis of intact chloroplasts: interaction with manganese. | highly purified, intact chloroplasts were prepared from pea (pisum sativum l.) and spinach (spinacia oleracea l.) following an identical procedure, and were used to investigate the cupric cation inhibition on the photosynthetic activity. in both species, copper inhibition showed a similar inhibitor concentration that decreases the enzyme activity by 50% (ic(50) approximately 1.8 microm) and did not depend on the internal or external phosphate (pi) concentration, indicating that copper did not in ... | 2010 | 20051028 |
| nitrogen nutrition and antioxidant metabolism in ammonium-tolerant and -sensitive plants. | ammonium nutrition is of interest as an alternative to that of using nitrate. however, the former has been reported as stressful to many plant species especially to some important crops, as most abiotic stresses may trigger oxidative imbalances in plants. in this work, we investigate the response of oxidative metabolism of two plant species, spinach (spinacia oleracea l. cv. gigante de invierno) and pea (pisum sativum l. cv. rondo), which have distinct tolerance to ammonium. plants were grown in ... | 2008 | 18275467 |
| decarboxylation of glycine contributes to carbon isotope fractionation in photosynthetic organisms. | carbon isotope effects were investigated for the reaction catalyzed by the glycine decarboxylase complex (gdc; ec 2.1.2.10). mitochondria isolated from leaves of pea (pisum sativum l.) and spinach (spinacia oleracea l.) were incubated with glycine, and the co(2) evolved was analyzed for the carbon isotope ratio (delta(13)c). within the range of parameters tested (temperature, ph, combination of cofactors nad(+), adp, pyridoxal 5-phosphate), carbon isotope shifts of co(2) relative to the c(1)-car ... | 2001 | 16228305 |
| salinity promotes accumulation of 3-dimethylsulfoniopropionate and its precursor s-methylmethionine in chloroplasts. | wollastonia biflora (l.) dc. plants accumulate the osmoprotectant 3-dimethylsulfoniopropionate (dmsp), particularly when salinized. dmsp is known to be synthesized in the chloroplast from s-methylmethionine (smm) imported from the cytosol, but the sizes of the chloroplastic and extrachloroplastic pools of these compounds are unknown. we therefore determined dmsp and smm in mesophyll protoplasts and chloroplasts. salinization with 30% (v/v) artificial seawater increased protoplast dmsp levels fro ... | 1998 | 9449841 |
| affinity purification of ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit epsilon n-methyltransferase. | ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit epsilon n-methyltransferase (protein methylase iii, rubisco lsmt, ec 2.1.1.43) catalyzes methylation of the epsilon-amino group of lys-14 in the large subunit of rubisco. in this paper, an affinity purification procedure for pea (pisum sativum l. cv laxton's progress no. 9) rubisco lsmt is described and characterized. spinach (spinacia oleracea l. cv melody) rubisco, a substrate for pea rubisco lsmt, was immobilized to polyvinylidene ... | 1995 | 8527940 |
| distribution of pyruvate dehydrogenase complex activities between chloroplasts and mitochondria from leaves of different species. | protoplasts from barley (hordeum vulgare), pea (pisum sativum), wheat (triticum aestivum), and spinach (spinacia oleracea) leaves were fractionated into chloroplast- and mitochondrion-enriched fractions. pyruvate dehydrogenase complex capacities in mitochondria (mtpdc) and chloroplasts (cppdc) were measured in appropriate fractions under conditions optimal for each isozyme. the total cellular capacity of pdc was similar in barley and pea but about 50% lower in wheat and spinach. in pea a distrib ... | 1994 | 12232437 |
| antigenic relationships between chloroplast and cytosolic fructose-1,6-bisphosphatases. | cytosolic fructose-1,6-biphosphatases (fbpase, ec 3.1.3.11) from pea (pisum sativum l. cv lincoln) and spinach (spinacia oleracea l. cv winter giant) did not cross-react by double immunodiffusion and western blotting with either of the antisera raised against the chloroplast enzyme of both species; similarly, pea and spinach chloroplast fbpases did not react with the spinach cytosolic fbpase antiserum. on the other hand, spinach and pea chloroplast fbpases showed strong cross-reactions against t ... | 1994 | 7512735 |
| adp/atp translocator from pea root plastids (comparison with translocators from spinach chloroplasts and pea leaf mitochondria). | the kinetic properties of the adenosine 5[prime]-diphosphate/adenosine 5[prime]-triphosphate (adp/atp) translocator from pea (pisum sativum l.) root plastids were determined by silicone oil filtering centrifugation and compared with those of spinach (spinacia oleracea l.) chloroplasts and pea leaf mitochondria. in addition, the adp/atp transporting activities from the above organelles were reconstituted into liposomes. the km(atp) value of the pea root adp/atp translocator was 10 [mu]m and that ... | 1993 | 12231920 |
| is acetylcarnitine a substrate for fatty acid synthesis in plants? | long-chain fatty acid synthesis from [1-14c]acetylcarnitine by chloroplasts isolated from spinach (spinacia oleracea), pea (pisum sativum), amaranthus (amaranthus lividus), or maize (zea mays) occurred at less than 2% of the rate of fatty acid synthesis from [1-14c]acetate irrespective of the maturity of the leaves or whether the plastids were purified using sucrose or percoll medium. [1-14c]-acetylcarnitine was not significantly utilized by highly active chloroplasts rapidly prepared from pea a ... | 1993 | 12231767 |
| assay of proton-coupled glycolate and d-glycerate transport into chloroplast inner envelope membrane vesicles by stopped-flow fluorescence. | the transport of glycolate and d-glycerate across the inner envelope membrane of intact chloroplasts is rapid and mediated by a translocator with proton/substrate symport activity. the true initial rate of glycolate or d-glycerate transport could not be measured by conventional methods. to resolve the initial rates of glycolate and d-glycerate transport, a stopped-flow fluorescence assay was developed that allows the indirect observation of transport from about 4 ms after mixing. inner envelope ... | 1993 | 12231730 |
| cloning and sequencing of a cdna for the delta-subunit of photosynthetic atp-synthase (ec 3.6.1.34) from pea (pisum sativum). | lambda gt10 cdna clones for the nuclear encoded subunit delta of chloroplast atp-synthase from pisum sativum have been isolated. the 5' end was completed by pcr. the sequenced cdna codes for the import precursor. n-terminal sequencing of the mature protein isolated from chloroplasts revealed that the processing sites of the transit peptide from pisum sativum and spinacea oleracea are similar. the overall homology of the deduced amino acid sequences of the mature delta proteins from higher plants ... | 1992 | 1482682 |
| regulation of plant fatty acid biosynthesis : analysis of acyl-coenzyme a and acyl-acyl carrier protein substrate pools in spinach and pea chloroplasts. | in previous work (d. post-beittenmiller, j.g. jaworski, j.b. ohlrogge [1991] j biol chem 266: 1858-1865), the in vivo acyl-acyl carrier protein (acp) pools were measured in spinach (spinacia oleracea) leaves and changes in their levels were compared to changes in the rates of fatty acid biosynthesis. to further examine the pools of substrates and cofactors for fatty acid biosynthesis and to evaluate metabolic regulation of this pathway, we have now examined the coenzyme a (coa) and short chain a ... | 1992 | 16653077 |
| chloroplast biogenesis. cell-free transfer of envelope monogalactosylglycerides to thylakoids. | an atp- and temperature-dependent transfer of monogalactosylglycerides from the chloroplast envelope to the chloroplast thylakoids was reconstituted in a cell-free system prepared from isolated chloroplasts of garden pea (pisum sativum) or spinach (spinacia oleracea). isolated envelope membranes, in which the label was present exclusively in monogalactosylglycerides, were prepared radiolabeled in vitro with [14c]galactose from udp-[14c]galactose to label galactolipids as the donor. atp-dependent ... | 1991 | 1764456 |
| ion relations of symplastic and apoplastic space in leaves from spinacia oleracea l. and pisum sativum l. under salinity. | salt tolerant spinach (spinacia oleracea) and salt sensitive pea (pisum sativum) plants were exposed to mild salinity under identical growth conditions. in order to compare the ability of the two species for extra- and intracellular solute compartmentation in leaves, various solutes were determined in intercellular washing fluids and in aqueously isolated intact chloroplasts. in pea plants exposed to 100 millimolar nacl for 14 days, apoplastic salt concentrations in leaflets increased continuous ... | 1991 | 16668541 |
| molecular cloning and structural analysis of the phosphate translocator from pea chloroplasts and its comparison to the spinach phosphate translocator. | using an 5'-avaii fragment of the spinach (spinacia oleracea l.) phosphate translocator cdna as a probe for a hybridization screening of a pea (pisum sativum l.) cdna library we have cloned and sequenced a cdna clone coding for the phosphate translocator precursor protein from pea chloroplasts. the full-length cdna clone comprises 42 base pairs (bp) at the 5'-non-coding region, a 1206-bp coding region corresponding to a polypeptide of 402 amino-acid residues (relative molecular mass 43 671) and ... | 1991 | 24193755 |
| polysaccharide fraction from higher plants which strongly interacts with the cytosolic phosphorylase isozyme : i. isolation and characterization. | from leaves of spinacia oleracea l. or from pisum sativum l. and from cotyledons of germinating pea seeds a high molecular weight polysaccharide fraction was isolated. the apparent size of the fraction, as determined by gel filtration, was similar to that of dextran blue. following acid hydrolysis the monomer content of the polysaccharide preparation was studied using high pressure liquid and thin layer chromatography. glucose, galactose, arabinose, and ribose were the main monosaccharide compou ... | 1990 | 16667877 |
| biosynthesis of digalactosyldiacylglycerol in plastids from 16:3 and 18:3 plants. | intact chloroplasts isolated from leaves of eight species of 16:3 and 18:3 plants and chromoplasts isolated from narcissus pseudonarcissus l. flowers synthesize galactose-labeled mono-, di-, and trigalactosyldiacylglycerol (mgdg, dgdg, and tgdg) when incubated with udp-[6-(3)h]galactose. in all plastids, galactolipid synthesis, and especially synthesis of dgdg and tgdg, is reduced by treatment of the organelles with the nonpenetrating protease thermolysin. envelope membranes isolated from thermo ... | 1990 | 16667615 |
| characterization and compartmentation, in green leaves, of hexokinases with different specificities for glucose, fructose, and mannose and for nucleoside triphosphates. | when green leaves of spinach (spinacia oleracea l.) were surveyed for the presence of hexokinases which utilize glucose, fructose and-or mannose as a substrate, four kinases could be distinguished by their order of elution during chromatography on diethylaminoethyl (deae)-cellulose: (i) a hexokinase i with a specificity for fructose, glucose, and mannose, (ii) a fructokinase i with a specificity for fructose, (iii) a hexokinase ii with a specificity for glucose, fructose and mannose, and (iv) a ... | 1990 | 24196745 |
| evidence for a ferredoxin-dependent choline monooxygenase from spinach chloroplast stroma. | chenopods synthesize betaine in the chloroplast via a two-step oxidation of choline: choline --> betaine aldehyde --> betaine. our previous experiments with intact chloroplasts, and in vivo(18)o(2) labeling studies, led us to propose that the first step is mediated by a monooxygenase which uses photosynthetically generated reducing power (c lerma, ad hanson, d rhodes [1988] plant physiol 88: 695-702). here, we report the detection of such an activity in vitro. in the presence of o(2) and reduced ... | 1989 | 16666757 |
| the association of d-ribulose- 1,5-bisphosphate carboxylase/oxygenase with phosphoribulokinase. | when ribulose- 1,5-bisphosphate carboxylase/oxygenase was purified from spinach leaves (spinacia oleracea) using precipitation with polyethylene glycol and mgcl(2) followed by deae cellulose chromatography, 75% of phosphoribulokinase and 7% of phosphoriboisomerase activities copurified with ribulose- 1,5-bisphosphate carboxylase/oxygenase. this enzyme preparation showed ribose-5-phosphate and ribulose-5-phosphate dependent carboxylase and oxygenase activities which were nearly equivalent to its ... | 1989 | 16666540 |
| role of plastidial acyl-acyl carrier protein: glycerol 3-phosphate acyltransferase and acyl-acyl carrier protein hydrolase in channelling the acyl flux through the prokaryotic and eukaryotic pathway. | in order to investigate whether the relative activities of the plastidial acyl-acyl carrier protein (acp):glycerol 3-phosphate acyltransferase (ec 2.3.1.15) and acyl-acp hydrolase play a role in controlling the acyl flux through the prokaryotic and eukaryotic pathway, we determined these enzymic activities in stroma fractions from 16:3- and 18:3-plants using glycerol 3-phosphate and labelled acyl-acp as substrates. several factors were examined which might influence the activities within plastid ... | 1988 | 24220947 |