Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| glv supplements increased plasma beta-carotene, vitamin c, zinc and hemoglobin in young healthy adults. | green leafy vegetables (glv) are rich sources of beta-carotene, iron and other micronutrients. our in vitro studies have demonstrated good antioxidant potential in glv. moreover linkages of glv intakes with plasma retinol and ascorbic acid were seen in apparently healthy indians. | 2006 | 15834756 |
| determination of beta-carotene and lutein available from green leafy vegetables by an in vitro digestion and colonic fermentation method. | green leafy vegetables (spinacea oleracea, cnidoscolus aconitifolius, and solanum americanum) contain a high amount of beta-carotene (27-52 mg/100 g of dry sample) and lutein (140-193 mg/100 g of dry sample). the amount of beta-carotene and lutein released from the food matrix by the action of digestive enzymes ranged from 22 to 67% and from 27 to 77%, respectively. there was a significant correlation between the enzymatic release of carotenoids (lutein + beta-carotene) and the content of klason ... | 2005 | 15826042 |
| determination of major carotenoids in a few indian leafy vegetables by high-performance liquid chromatography. | leafy vegetables [basella rubra l., peucedanum sowa roxb., moringa oleifera lam., trigonella foenum-graecum l., spinacia oleracea l., sesbania grandiflora (l.) poir., and raphanus sativus l.] that are commonly used by the rural population in india were evaluated in terms of their main carotenoid pattern. the extracted carotenoids were purified by open column chromatography (occ) on a neutral alumina column to verify their identity by their characteristic uv-visible absorption spectra. reverse-ph ... | 2005 | 15826027 |
| molecular cloning of ga 2-oxidase3 from spinach and its ectopic expression in nicotiana sylvestris. | previous work has shown that 13-hydroxylated gibberellins (gas) are predominant in the long-day (ld) plant spinach (spinacia oleracea; ga53, ga44, ga19, ga20, ga1, ga8, and ga29). also present in spinach are 2-hydroxylated c20-gas: ga97, ga98, ga99, and ga110. levels of the most abundant ga, ga97, decreased when plants were transferred from short photoperiods (sd) to ld. when [14c]ga53 was fed to spinach plants, more ga53 was converted to ga97 in sd than in ld, and more radioactive ga20 was form ... | 2005 | 15821147 |
| dietary supplementation with blueberries, spinach, or spirulina reduces ischemic brain damage. | free radicals are involved in neurodegenerative disorders, such as ischemia and aging. we have previously demonstrated that treatment with diets enriched with blueberry, spinach, or spirulina have been shown to reduce neurodegenerative changes in aged animals. the purpose of this study was to determine if these diets have neuroprotective effects in focal ischemic brain. adult male sprague-dawley rats were fed with equal amounts of diets (blueberry, spinach, and spirulina) or with control diet. a ... | 2005 | 15817266 |
| thermostability and ca2+ binding properties of wild type and heterologously expressed psbo protein from cyanobacterial photosystem ii. | oxygenic photosynthesis takes place in the thylakoid membrane of cyanobacteria, algae, and higher plants. initially light is absorbed by an oligomeric pigment-protein complex designated as photosystem ii (psii), which catalyzes light-induced water cleavage under release of molecular oxygen for the biosphere on our planet. the membrane-extrinsic manganese stabilizing protein (psbo) is associated on the lumenal side of the thylakoids close to the redox-active (mn)(4)ca cluster at the catalytically ... | 2005 | 15779895 |
| size determination of cyanobacterial and higher plant photosystem ii by gel permeation chromatography, light scattering, and ultracentrifugation. | the oxygen-evolving photosystem ii core complexes (psiicc) from the thermophilic cyanobacterium thermosynechococcus elongatus (psiiccte) and the higher plant spinacia oleracea (psiiccso) have been isolated from the thylakoid membrane by solubilization with n-dodecyl-beta-d-maltoside, purified and characterized by gel permeation chromatography (gpc), dynamic light scattering (dls), and analytical ultracentrifugation (auc). dls suggests that psiicc from both organisms exists as a monomer in dilute ... | 2005 | 15766288 |
| n-terminal deletion of the gamma subunit affects the stabilization and activity of chloroplast atp synthase. | five truncation mutants of chloroplast atp synthase gamma subunit from spinach (spinacia oleracea) lacking 8, 12, 16, 20 or 60 n-terminal amino acids were generated by pcr by a mutagenesis method. the recombinant gamma genes were overexpressed in escherichia coli and assembled with alphabeta subunits into a native complex. the wild-type (wt) alphabetagamma assembly i.e. alphabetagammawt exhibited high (mg2+)-dependent and (ca2+)-dependent atp hydrolytic activity. deletions of eight residues of t ... | 2005 | 15752355 |
| development of a procedure for the sequential extraction of substances binding trace elements in plant biomass. | this work investigates how the amounts of some important substances in a plant, and their behaviour inside the plant, depend on the levels of stress placed on the plant. to this end, model plant spinach (spinacia oleracea l.) was cultivated on soil treated with sewage sludge. the sewage sludge contained various trace elements (as, cd, cu, zn), and the uptake of these trace elements placed the plant under stress. following this, a sequential extraction procedure was employed to determine the leve ... | 2005 | 15750871 |
| transient homodimer interactions studied using the electron self-exchange reaction. | transient homodimer protein interactions have been investigated by analyzing the influence of ionic strength (nacl) on the electron self-exchange (the bimolecular reaction whereby the two oxidation states of a redox protein interconvert) rate constant (k(ese)) of four plastocyanins. the k(ese) values for the plastocyanins from spinach, dryopteris crassirhizoma (a fern), and the green alga ulva pertusa, which possess acidic patches of varying size and locations, increase 190-, 29-, and 21-fold, r ... | 2005 | 15743773 |
| a multi-biosensor based on immobilized photosystem ii on screen-printed electrodes for the detection of herbicides in river water. | a multi-biosensor for detection of herbicides and pollutants was constructed using various photosynthetic preparations as biosensing elements. the photosynthetic thylakoid from spinacia oleracea l., senecio vulgaris and its mutant resistant to atrazine were immobilized with (bsa-ga) on the surface of screen-printed sensors composed of a graphite-working electrode and ag/agcl reference electrode deposited on a polymeric substrate. the biosensor was composed of four flow cells with independent ill ... | 2005 | 15741067 |
| identification and characterization of a novel plastidic adenine nucleotide uniporter from solanum tuberosum. | homologs of bt1 (the brittle1 protein) are found to be phylogenetically related to the mitochondrial carrier family and appear to occur in both mono- and dicotyledonous plants. whereas bt1 from cereals is probably involved in the transport of adp-glucose, which is essential for starch metabolism in endosperm plastids, bt1 from a noncereal plant, solanum tuberosum (stbt1), catalyzes an adenine nucleotide uniport when functionally integrated into the bacterial cytoplasmic membrane. import studies ... | 2005 | 15737999 |
| aluminium resistance requires resistance to acid stress: a case study with spinach that exudes oxalate rapidly when exposed to al stress. | spinach is a vegetable with a high oxalate concentration in its tissues. oxalate efflux from spinach (spinacia oleracea l. cv. quanneng) roots was rapidly stimulated (within 30 min) by aluminium (al) treatment. the efflux was constant within 6 h, but increased with increasing al concentration. the efflux was confined to the root tip (0-5 mm), which showed a 5-fold greater efflux than the root zone distal to the tip (5-10 mm). oxalate efflux could not be triggered by treatment with the trivalent ... | 2005 | 15737984 |
| investigations on the reaction pattern of photosystem ii in leaves from arabidopsis thaliana by time-resolved fluorometric analysis. | the transients of normalized fluorescence yield induced by an actinic laser flash in dark adapted leaves of arabidopsis thaliana plants were measured with new equipment, that was developed as part of this work and permits the covarage of a wide time domain of 8 decades from 100 ns to 10 s. the raw data obtained were processed and analyzed within the framework of the "3-quencher" model with q(a) as photochemical and p680(+)(*) and (3)car as nonphotochemical quenchers. comparative measurements wit ... | 2005 | 15736922 |
| diatom plastids possess a phosphoribulokinase with an altered regulation and no oxidative pentose phosphate pathway. | the chloroplast enzyme phosphoribulokinase (prk; ec 2.7.1.19) is part of the calvin cycle (reductive pentose phosphate pathway) responsible for co(2) fixation in photosynthetic organisms. in green algae and vascular plants, this enzyme is light regulated via reversible reduction by reduced thioredoxin. we have sequenced and characterized the gene of the prk from the marine diatom odontella sinensis and found that the enzyme has the conserved cysteine residues necessary for thioredoxin-dependent ... | 2005 | 15734914 |
| plant based hiv-1 vaccine candidate: tat protein produced in spinach. | the hiv-1 tat protein has been recently explored as a prospective vaccine candidate with broad, subtype non-specific action. we approached the problem of delivery of tat through the mucosal route by expressing tat in an edible plant. the tat gene was assembled from synthetic overlapping oligonucleotides, and was subsequently cloned into a plant virus-based vector tobacco mosaic virus (tmv). spinach plants inoculated with the tat-producing constructs were collected and fed to mice 7-14 days post ... | 2005 | 15734059 |
| at least two toc34 protein import receptors with different specificities are also present in spinach chloroplasts. | the receptor components of the chloroplast protein import machinery, toc34 and toc159, are both encoded by small gene families in arabidopsis thaliana. recent results suggest that each member of these families preferentially interacts with different groups of precursor proteins. here we address the question, whether multiple homologous toc receptors are unique to arabidopsis or whether they are a general phenomenon in plants. indeed, in spinach we could identify at least two toc34 proteins with ... | 2005 | 15733839 |
| the carboxyterminal processing protease of d1 protein: expression, purification and enzymology of the recombinant and native spinach proteins. | the carboxyterminal processing protease of d1 protein (ctpa) is predicted to be an excellent target for a general broad-spectrum herbicide. the gene for spinach ctpa has been expressed in escherichia coli. the expressed protein that was found mainly in inclusion bodies has been purified and refolded on a nickel-chelate column. active recombinant ctpa was recovered. two assays for ctpa activity were developed, a medium-throughput hplc assay using a fluorescent substrate and a high-throughput assa ... | 2005 | 15726567 |
| effect of chlorella pyrenoidosa on fecal excretion and liver accumulation of polychlorinated dibenzo-p-dioxin in mice. | the effect of chlorella pyrenoidosa on fecal excretion and liver accumulation of polychlorinated dibenzo-p-dioxin in c57bl/6n mice administered dioxin was examined. mice were administered 2.2 microg of 1,2,3,4,7,8-hexachlorodibenzo-p-dioxin (h6cdd) dissolved in corn oil once after a period of acclimatization, after which they were fed either a basal diet, a 10% c. pyrenoidosa diet, or a 10% spinach diet, for five weeks. among mice fed the 10% c. pyrenoidosa diet, cumulative fecal excretion of h6 ... | 2005 | 15722102 |
| interactions of escherichia coli o157:h7, salmonella typhimurium and listeria monocytogenes plants cultivated in a gnotobiotic system. | the growth and persistence of escherichia coli o157:h7, salmonella typhimurium and listeria monocytogenes on a diverse range of plant types over extended cultivation periods was studied. when introduced on the seed of carrot, cress, lettuce, radish, spinach and tomato all the pathogens became rapidly established shortly after germination, attaining cell densities of the order of 5.5-6.5 log cfu/g. in general, es. coli o157:h7 and l. monocytogenes became established and persisted at significantly ... | 2005 | 15718025 |
| plant ribulosamine/erythrulosamine 3-kinase, a putative protein-repair enzyme. | fn3k (fructosamine 3-kinase) is a mammalian enzyme that catalyses the phosphorylation of fructosamines, which thereby becomes unstable and detaches from proteins. the homologous mammalian enzyme, fn3k-rp (fn3k-related protein), does not phosphorylate fructosamines but ribulosamines, which are probably formed through a spontaneous reaction of amines with ribose 5-phosphate, an intermediate of the pentose-phosphate pathway and the calvin cycle. we show in the present study that spinach leaf extrac ... | 2005 | 15705060 |
| ph dependence of the flash-induced s-state transitions in the oxygen-evolving center of photosystem ii from thermosynechoccocus elongatus as revealed by fourier transform infrared spectroscopy. | ph dependence of the efficiencies of the flash-induced s-state transitions in the oxygen-evolving center (oec) was studied by means of fourier transform infrared (ftir) difference spectroscopy using photosystem ii (psii) core complexes from the thermophilic cyanobacterium thermosynechoccocus elongatus. the psii core complexes dark-adapted at different phs in the presence of ferricyanide as an electron acceptor were excited by four consecutive saturating laser flashes, and ftir difference spectra ... | 2005 | 15683255 |
| crystal structure analysis of recombinant rat kidney long chain hydroxy acid oxidase. | long chain hydroxy acid oxidase (lchao) is a member of an fmn-dependent enzyme family that oxidizes l-2-hydroxy acids to ketoacids. lchao is a peroxisomal enzyme, and the identity of its physiological substrate is unclear. mandelate is the most efficient substrate known and is commonly used in the test tube. lchao differs from most family members in that one of the otherwise invariant active site residues is a phenylalanine (phe23) instead of a tyrosine. we now report the crystal structure of lc ... | 2005 | 15683236 |
| effects of dna polymerase inhibitory and antitumor activities of lipase-hydrolyzed glycolipid fractions from spinach. | we succeeded in purifying the major glycolipid fraction in the class of sulfoquinovosyl diacylglycerol, monogalactosyl diacylglycerol and digalactosyl diacylglycerol (dgdg) from a green vegetable, spinach (spinacia oleracea l.). this glycolipid fraction was an inhibitor of dna polymerases and a growth inhibitor of nugc-3 human gastric cancer cells, and, interestingly, the activities were much stronger when the fraction was hydrolyzed by lipase. glycolipids in the hydrolyzed fraction consisted of ... | 2005 | 15681172 |
| characterization of spapetala3 and sppistillata, b class floral identity genes in spinacia oleracea, and their relationship to sexual dimorphism. | floral organ identity b class genes are generally recognized as being required for development of petals and stamens in angiosperm flowers. spinach flowers are distinguished in their complete absence of petals in both sexes, and the absence of a developed stamen whorl in female flowers. as such, we hypothesized that differential expression of b class floral identity genes is integral to the sexual dimorphism in spinach flowers. we isolated two spinach orthologs of arabidopsis b class genes by 3' ... | 2005 | 15660251 |
| light-induced proton slip and proton leak at the thylakoid membrane. | a treatment of leaves of spinacia oleracea l. with light or with the thiol reagent dithiothreitol in the dark led to partly uncoupled thylakoids. after induction in intact leaves, the partial uncoupling was irreversible at the level of isolated thylakoids. we distinguish between uncoupling by proton slip, which means a decrease of the h+/e(-) -ratio due to less efficient proton pumping, and proton leak as defined by enhanced kinetics of proton efflux. proton slip and proton leak made about equal ... | 2004 | 15658803 |
| dietary antioxidants and cardiovascular disease. | oxidative damage is involved in cardiovascular diseases. intervention with alpha-tocopherol, ascorbic acid and beta-carotene does not appear to reduce pathogenesis. the purpose of this review is to describe alternative antioxidant mechanisms that may be involved. | 2005 | 15650563 |
| comparative structural analysis of oxidized and reduced thioredoxin from drosophila melanogaster. | thioredoxins (trx) participate in essential antioxidant and redox-regulatory processes via a pair of conserved cysteine residues. in dipteran insects like drosophila and anopheles, which lack a genuine glutathione reductase (gr), thioredoxins fuel the glutathione system with reducing equivalents. thus, characterizing trxs from these organisms contributes to our understanding of redox control in gr-free systems and provides information on novel targets for insect control. cytosolic trx of drosoph ... | 2004 | 15644209 |
| feeding of spinach or sweet-potato leaves and growth performance of growing pigs kept on smallholder farms in central vietnam. | we investigated whether the addition of either spinach or sweet-potato leaves to the diet of growing pigs, kept in small holdings in central vietnam, would improve growth performance. a control diet was formulated and mixed with each of the vegetables to a final concentration of 15% of the total dietary dry matter. the diets were fed to the pigs from 70 to 100 days of age on six different smallholder farms in central vietnam. there were three animals per treatment group per farm and biopsies of ... | 2004 | 15643817 |
| synthesis and assembly of thylakoid protein complexes: multiple assembly steps of photosystem ii. | to study the synthesis and assembly of multisubunit thylakoid protein complexes, we performed [35s]met pulse and chase experiments with isolated chloroplasts and intact leaves of spinach (spinacia oleracea l.), followed by blue native gel separation of the (sub)complexes and subsequent identification of the newly synthesized and assembled protein subunits. psii (photosystem ii) core subunits were the most intensively synthesized proteins, particularly in vitro and at high light intensities in vi ... | 2005 | 15638811 |
| spinacia oleracea l. protects against gamma radiations: a study on glutathione and lipid peroxidation in mouse liver. | the present study deals with the protective effect of spinacia oleracea l. against radiation-induced oxidative stress, which is evaluated in terms of lipid peroxidation (lpo) product and tissue levels of glutathione. swiss albino male mice aged 6-8 weeks, weighing 22+/-3 g, each were selected from an inbred colony and divided into four groups. one group served as normal and a second group (extract of s. oleracea l. (se) treated un-irradiated) were administered methanolic (50%) se at a dose of 11 ... | 2004 | 15636174 |
| phytoecdysteroids: a novel defense against plant-parasitic nematodes. | the phytoecdysteroid, 20-hydroxyecdysone (20e), is a major molting hormone of invertebrates, possibly including nematodes. as 20e is inducible in spinach, the defensive role against plant-parasitic nematodes was investigated. the effects of direct application on nematodes was assessed by treating cereal cyst nematode, heterodera avenae, juveniles with concentrations of 20e from 8.2 x 10(-8) to 5.2 x 10(-5) m before applying to triticum aestivum growing in sand. h. avenae, heterodera schachtii (s ... | 2004 | 15609826 |
| competitive inhibitors of mycobacterium tuberculosis ribose-5-phosphate isomerase b reveal new information about the reaction mechanism. | ribose-5-phosphate isomerase (rpi), an important enzyme in the pentose phosphate pathway, catalyzes the interconversion of ribulose 5-phosphate and ribose 5-phosphate. two unrelated isomerases have been identified, rpia and rpib, with different structures and active site residues. the reaction catalyzed by both enzymes is thought to proceed via a high energy enediolate intermediate, by analogy to other carbohydrate isomerases. here we present studies of rpib from mycobacterium tuberculosis toget ... | 2004 | 15590681 |
| two distinct redox signaling pathways for cytosolic apx induction under photooxidative stress. | the cross-talk of two redox factors, h2o2 accumulation and redox status of photosynthetic electron transport (pet) in tobacco chloroplasts, on the expression of cytosolic ascorbate peroxidase (capx) was studied. transgenic tobacco plants, which expressed respectively the escherichia coli catalase and spinach thylakoid-membrane-bound apx in chloroplasts and showed increased tolerance to photooxidative stress, were used for evaluation of the relationship between h2o2 accumulation or change of redo ... | 2004 | 15574834 |
| selecting iodine-enriched vegetables and the residual effect of iodate application to soil. | a greenhouse pot experiment was conducted to select vegetables for iodine uptake. the residual effect of iodate fertilization on the growth of and iodine uptake by spinach plants were also investigated. six vegetables, including leafy vegetables (pakchoi [brassica chinensis l.], spinach [spinacia oleracea l.]), tuber vegetables (onion [allium cepa l.]), shoot vegetables (water spinach [ipomoea aquatica forsk.], celery [apium graveolens l.]), and root vegetables (carrot [daucus carota var. sativa ... | 2004 | 15564656 |
| potential anticancer effect of red spinach (amaranthus gangeticus) extract. | the objective of this study was to determine the anti cancer effects of red spinach (amaranthus gangeticus linn) in vitro and in vivo. for in vitro study, microtitration cytotoxic assay was done using 3-(4,5-dimethylthiazol-2-il)-2,5-diphenil tetrazolium bromide (mtt) kit assay. results showed that aqueous extract of a gangeticus inhibited the proliferation of liver cancer cell line (hepg2) and breast cancer cell line (mcf-7). the ic(50) values were 93.8 mu g/ml and 98.8 mu g/ml for hepg2 and mc ... | 2004 | 15563447 |
| green vegetables, red meat and colon cancer: chlorophyll prevents the cytotoxic and hyperproliferative effects of haem in rat colon. | diets high in red meat and low in green vegetables are associated with increased colon cancer risk. this association might be partly due to the haem content of red meat. in rats, dietary haem is metabolized in the gut to a cytotoxic factor that increases colonic cytotoxicity and epithelial proliferation. green vegetables contain chlorophyll, a magnesium porphyrin structurally analogous to haem. we studied whether green vegetables inhibit the unfavourable colonic effects of haem. first, rats were ... | 2005 | 15550456 |
| interleukin 4 increases the antibody response against rubisco in mice. | the influence of interleukin 4 (il-4) on antibody titer in serum and spleen culture supernatant in mice immunized with spinach (spinacia oleracea l.) rubisco was investigated. therefore, we boosted one mouse additionally to the antigen with recombinant mouse il-4. we found that the rubisco-specific antibody titer in serum as well as in spleen cell culture supernatant was significantly enhanced in the il-4 mouse. most of the antibodies were of the igg1 subclass. after hybridoma generation, rubisc ... | 2004 | 15523907 |
| structural stability of the psbq protein of higher plant photosystem ii. | we have characterized the stability and folding behavior of the isolated extrinsic psbq protein of photosystem ii (psii) from a higher plant, spinacia oleracea, using intrinsic protein fluorescence emission and near- and far-uv circular dichroism (cd) spectroscopy in combination with differential scanning calorimetry (dsc). experimental results reveal that both chemical denaturation using guanidine hydrochloride (gdnhcl) and thermal unfolding of psbq proceed as a two-state reversible process. th ... | 2004 | 15518567 |
| dihydroflavonol 4-reductase cdna from non-anthocyanin-producing species in the caryophyllales. | two types of red pigment, anthocyanins and betacyanins, never occur together in the same plant. although anthocyanins are widely distributed in higher plants as flower and fruit pigments, betacyanins have replaced anthocyanins in the caryophyllales. we isolated cdnas encoding dihydroflavonol 4-reductase (dfr), which is the first enzyme committed to anthocyanin biosynthesis in the flavonoid pathway, from spinacia oleracea and phytolacca americana, plants that belong to the caryophyllales. the ded ... | 2004 | 15509852 |
| feedback inhibition of spinach l-galactose dehydrogenase by l-ascorbate. | we have studied the enzymological properties of l-galactose dehydrogenase (l-galdh), a key enzyme in the biosynthetic pathway of l-ascorbate (asa) in plants. l-galdh was purified approximately 560-fold from spinach leaves. the enzyme was a homodimer with a subunit mass of 36 kda. we also cloned the full-length cdna of spinach l-galdh, which contained an open reading frame encoding 322 amino acid residues with a calculated molecular mass of 35,261 da. the deduced amino acid sequence of the cdna s ... | 2004 | 15509850 |
| determining bioavailability of food folates in a controlled intervention study. | the concept of dietary folate equivalents (dfes) in the united states recognizes the differences in bioavailability between natural food folates and the synthetic vitamin, folic acid. however, many published reports on folate bioavailability are problematic because of several confounding factors. | 2004 | 15447898 |
| observation of calcium-dependent unidirectional rotational motion in recombinant photosynthetic f1-atpase molecules. | atp hydrolysis and synthesis by the f(0)f(1)-atp synthase are coupled to proton translocation across the membrane in the presence of magnesium. calcium is known, however, to disrupt this coupling in the photosynthetic enzyme in a unique way: it does not support atp synthesis, and caatp hydrolysis is decoupled from any proton translocation, but the membrane does not become leaky to protons. understanding the molecular basis of these calcium-dependent effects can shed light on the as yet unclear m ... | 2004 | 15377671 |
| degradation of malathion, in aqueous extracts of asparagus (asparagus officinalis). | malathion was incubated in water extracts of vegetables at various temperatures and ph, and the amount of malathion present over time was analyzed by a gas chromatograph with a flame photometric detector. malathion was degraded to a nondetectable level in a 1% asparagus extract incubated at ph 7.4 and 37 degrees c for 4 h. carrot extract showed the second highest rate of malathion degradation (76%), followed by kale extract (23.7%), spinach extract (9.7%), and broccoli extract (1.5%) under the s ... | 2004 | 15366843 |
| detection of glutathione reductase after electrophoresis on native or sodium dodecyl sulfate polyacrylamide gels. | commercial glutathione reductase (gr) from spinach and yeast (saccharomyces cerevisiae) were stained on 7.5% native polyacrylamide gel electrophoresis (page) gels or 15% sodium dodecyl sulfate (sds)-page gels with or without further purification by a 2',5'-adp sepharose 4b affinity column. for sds-page gels, the sds was removed first by washing twice with 25% isopropanol in 10 mm tris-hcl (ph 7.9) for 10 min. the gel was then dipped in a 50 mm tris-hcl buffer (ph 7.9) containing 4.0 mm oxidized ... | 2004 | 15349931 |
| preparation of polyclonal antibodies of rubisco large and small subunits and their application in the functional analysis of the genes. | spinach rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase) large (rbcl) and small (rbcs) subunits were separated by sds-page, and protein amount and purity were determined by bradford assay. polyclonal antibodies against rbcl and rbcs subunit were generated in female balb/c mice and had no cross-reaction with each other. a total of 81 microg antigens were used and 0.3 ml anti-sera with titer of 1:5000 were yielded. the antibodies were also applicable to study rbcl and rbcs in tobacco plan ... | 2004 | 15346203 |
| requirement of a relatively high threshold level of mg(2+) for cell growth of a rhizoplane bacterium, sphingomonas yanoikuyae ec-s001. | mg(2+) is one of the essential elements for bacterial cell growth. the presence of the magnesium cation (mg(2+)) in various concentrations often affects cell growth restoration in plant-associating bacteria. this study attempted to determine whether mg(2+) levels in sphingomonas yanoikuyae ec-s001 affected cell growth restoration in the host plant and what the threshold level is. s. yanoikuyae ec-s001, isolated from the rhizoplane of spinach seedlings grown from surface-sterilized seeds under as ... | 2004 | 15345402 |
| "respirasome"-like supercomplexes in green leaf mitochondria of spinach. | higher plant mitochondria have many unique features compared with their animal and fungal counterparts. this is to a large extent related to the close functional interdependence of mitochondria and chloroplasts, in which the two atp-generating processes of oxidative phosphorylation and photosynthesis, respectively, take place. we show that digitonin treatment of mitochondria contaminated with chloroplasts from spinach (spinacia oleracea) green leaves at two different buffer conditions, performed ... | 2004 | 15342644 |
| assessment of lutein bioavailability from meals and a supplement using simulated digestion and caco-2 human intestinal cells. | lutein and zeaxanthin are selectively accumulated in the lens and macular region of the retina. it was suggested that these xanthophylls protect ocular tissues from free-radical damage that can cause cataracts and age-related macular degeneration. insights regarding the absorption of dietary xanthophylls for delivery to ocular tissues are limited. our primary objective was to examine factors affecting the transfer of lutein from foods to absorptive intestinal epithelial cells during digestion. l ... | 2004 | 15333717 |
| an epoxide-furanoid rearrangement of spinach neoxanthin occurs in the gastrointestinal tract of mice and in vitro: formation and cytostatic activity of neochrome stereoisomers. | neoxanthin, a major carotenoid in green leafy vegetables, was reported to exhibit potent antiproliferative effect via apoptosis induction on human prostate cancer cells. however, the metabolic fate of dietary neoxanthin in mammals remains unknown. in the present study, we investigated the gastrointestinal metabolism of neoxanthin in mice and the in vitro digestion of spinach, and estimated the antiproliferative effect of neoxanthin metabolites on pc-3 human prostate cancer cells. two hours after ... | 2004 | 15333710 |
| cloning and characterization of a 2-cys peroxiredoxin from pisum sativum. | a cdna sequence coding for a pea (pisum sativum l.) 2-cys peroxiredoxin (2-cys prx) has been cloned. the deduced amino acid sequence showed a high sequence homology to the 2-cys prx enzymes of phaseolus vulgaris (86%), arabidopsis thaliana (75%), and spinacia oleracea (75%), and contained a chloroplast target sequence at its n-terminus. the mature enzyme, without the transit peptide, has a molecular mass of 22 kda as well as two cysteine residues (cys-53 and cys-175) which are well conserved amo ... | 2004 | 15333640 |
| unique natural antioxidants (naos) and derived purified components inhibit cell cycle progression by downregulation of pprb and e2f in human pc3 prostate cancer cells. | prostate cancer (pca) is the leading cause of cancer mortality among older men in western countries. epidemiological studies have shown correlation between a lower risk of pca and a higher consumption of antioxidants. however, the mechanism by which antioxidants exert their effects is still unknown. in the present study, we explored the signaling mechanism through which unique natural antioxidant derived from spinach extract (nao) exerts their beneficial effects in the chemoprevention of pca usi ... | 2004 | 15327971 |
| application of a new pcr primer for terminal restriction fragment length polymorphism analysis of the bacterial communities in plant roots. | contamination with plastid small subunit (ssu) rdna is a major drawback when analyzing the bacterial communities of plant roots using culture-independent methods. in this study, a polymerase chain reaction (pcr) primer, 783r, was designed and tested to specifically amplify the ssu rdna of various bacterial species without amplifying the ssu rdna of plant plastids. to confirm how useful the community analysis of rhizobacteria is using 783r, the terminal restriction fragment length polymorphism (t ... | 2004 | 15325755 |
| daily consumption of indian spinach (basella alba) or sweet potatoes has a positive effect on total-body vitamin a stores in bangladeshi men. | recent evidence suggests that the vitamin a equivalency of beta-carotene from plant sources is lower than previously estimated. | 2004 | 15321812 |
| betaine in human nutrition. | betaine is distributed widely in animals, plants, and microorganisms, and rich dietary sources include seafood, especially marine invertebrates ( approximately 1%); wheat germ or bran ( approximately 1%); and spinach ( approximately 0.7%). the principal physiologic role of betaine is as an osmolyte and methyl donor (transmethylation). as an osmolyte, betaine protects cells, proteins, and enzymes from environmental stress (eg, low water, high salinity, or extreme temperature). as a methyl donor, ... | 2004 | 15321791 |
| [test for urokinase-type plasminogen activator inhibitor of edible plants in vitro]. | to study the effect of anti-progression activity of edible plants using urokinase as the biomarker. | 2004 | 15312585 |
| snf1-related protein kinase (snrk1) phosphorylates class i heat shock protein. | the nucleotide sequence of cbsnip2, a cdna that had been cloned from a barley (hordeum vulgare) seed endosperm cdna library by two-hybrid screening with barley snf1-related protein kinase (snrki) was determined. it was found to contain a complete open reading frame encoding a class i heat shock protein. transcripts corresponding to the cdna (renamed cbhsp17) were detectable in rna isolated from barley seeds harvested in mid-development but not rna from roots or leaves. bhsp17 protein was express ... | 2004 | 15283126 |
| oxygen-dependent h2o2 production by rubisco. | oxygen and ribulose-1,5-bisphosphate dependent, h(2)o(2) production was observed with several wild type rubisco enzymes using a sensitive assay. h(2)o(2) and d-glycero-2,3-pentodiulose-1,5-bisphosphate, a known and potent inhibitor of rubisco activity, are predicted products arising from elimination of h(2)o(2) from a peroxyketone intermediate, specific to oxygenase activity. parallel assays using varying co(2) and o(2) concentrations revealed that the partitioning to h(2)o(2) during o(2) consum ... | 2004 | 15280029 |
| occurrence of plant-uncoupling mitochondrial protein (pump) in diverse organs and tissues of several plants. | the presence of plant-uncoupling mitochondrial protein (pump), previously described by vercesi et al. (1995), was screened in mitochondria of various organs or tissues of several plant species. this was done functionally, by monitoring purine nucleotide-sensitive linoleic acid-induced uncoupling, or by western blots. the following findings were established: (1) pump was found in most of the higher plants tested; (2) since atp inhibition of linoleic acid-induced membrane potential decrease varied ... | 2000 | 15254369 |
| a novel inhibitor of 9-cis-epoxycarotenoid dioxygenase in abscisic acid biosynthesis in higher plants. | abscisic acid (aba) is a major regulator in the adaptation of plants to environmental stresses, plant growth, and development. in higher plants, the aba biosynthesis pathway involves the oxidative cleavage of 9-cis-epoxycarotenoids, which may be the key regulatory step in the pathway catalyzed by 9-cis-epoxycarotenoid dioxygenase (nced). we developed a new inhibitor of aba biosynthesis targeting nced and named it abamine (aba biosynthesis inhibitor with an amine moiety). abamine is a competitive ... | 2004 | 15247398 |
| coenzyme site-directed mutants of photosynthetic a4-gapdh show selectively reduced nadph-dependent catalysis, similar to regulatory ab-gapdh inhibited by oxidized thioredoxin. | chloroplast glyceraldehyde-3-phosphate dehydrogenase (gapdh) of higher plants uses both nadp(h) and nad(h) as coenzyme and consists of one (gapa) or two types of subunits (gapa, gapb). ab-gapdh is regulated in vivo through the action of thioredoxin and metabolites, showing higher kinetic preference for nadph in the light than in darkness due to a specific effect on kcat(nadph). previous crystallographic studies on spinach chloroplast a4-gapdh complexed with nadp or nad showed that residues thr33 ... | 2004 | 15236965 |
| prevalence, antibiotic susceptibility, and virulence factors of yersinia enterocolitica and related species from ready-to-eat vegetables available in korea. | a total of 673 ready-to-eat vegetable samples were collected in korea from 2001 to 2002 and analyzed for the presence of yersinia spp. we analyzed biotypes, serotypes, and susceptibility to 12 antibiotics and tested for virulence genes of pathogenic yersinia enterocolitica isolates by pcr assay. among the samples, 27 (4.0%) were found to be contaminated with yersinia spp. among the 27 strains of yersinia spp. isolates, 18 strains (66.7%) of y. enterocolitica, 5 strains (18.5%) of y. frederikseni ... | 2004 | 15222537 |
| a monoclonal antibody to feruloylated-(1-->4)-beta-d-galactan. | we report the isolation and characterization of a monoclonal antibody, designated lm9, against feruloylated-(1-->4)-beta-d-galactan. this epitope is a structural feature of cell wall pectic polysaccharides of plants belonging to the family amaranthaceae (including the chenopodiaceae). immuno-assays and immunofluorescence microscopy indicated that lm9 binding is specific to samples and cell walls obtained from species belonging to this family. in a series of competitive-inhibition enzyme-linked i ... | 2004 | 15221383 |
| selenium as a sulphydrylic group inductor in plants. | we investigated the effect of selenium form and dose on the total glutathione and non-protein -sh group contents in the edible spinach (spinacia oleracea l.) and ground tomato (lycopersicon esculentum mill.) plants. our experiments were carried out in a hydroponic culture. selenium was added to the culture medium in its selenite (na2seo3 x 5h2o) and selenate (na2seo4) forms. regardless of the selenium form, we observed an increase in the non-protein thiol content. the non-protein -sh group conte ... | 2004 | 15213812 |
| the inhibitor dbmib provides insight into the functional architecture of the qo site in the cytochrome b6f complex. | previously [roberts, a. g., and kramer, d. m. (2001) biochemistry 40, 13407-13412], we showed that 2 equiv of the quinone analogue 2,5-dibromo-3-methyl-6-isopropylbenzoquinone (dbmib) could occupy the q(o) site of the cytochrome (cyt) b(6)f complex simultaneously. in this work, a study of electron paramagnetic resonance (epr) spectra from the oriented cyt b(6)f complex shows that the rieske iron-sulfur protein (isp) is in distinct orientations, depending on the stoichiometry of the inhibitor at ... | 2004 | 15196013 |
| isolation of cp43 and cp47 photosystem ii proximal antenna complexes from plants. | a single-column method to purify the cp43 and cp47 pigment-protein complexes of photo-system (ps)ii from higher plants is presented. to validate the isolation procedure, three different species were used (spinacea oleracea, beta vulgaris, and glycine max), and the procedure worked similarly with all three. oxygen-evolving core complex obtained from highly enriched psii membrane fragments were used as the starting material. the core complex is treated with the chaotropic agent liclo4 and the noni ... | 2004 | 15187275 |
| purification and crystallization of the cytochrome b6f complex in oxygenic photosynthesis. | the cytochrome b6f complex from the thermophilic cyanobacterium mastigocladus laminosus and spinach chloroplasts has been purified as a dimeric species. it was found by electrospray ionization mass spectroscopy to contain eight and nine subunits, respectively, and dimeric masses of 217,070 and 286,454 da. the subunits common to the complex from both sources are peta (cytochrome f), b (cytochrome b6), c (rieske iron-sulfur protein), d (subunit iv), and small 3.2-4.2 kda polypeptides petg,l,m, and ... | 2004 | 15187270 |
| heavy metal uptake by spinach leaves grown on contaminated soils with lead, mercury, cadmium, and nickel. | spinach plants were grown in soil pots contaminated with increasing mixtures of lead, mercury, cadmium, and nickel salts. plants in the control soil were grown in the absence of the heavy metals mixture. the elemental distribution of cd, ni, pb, and hg in the roots and leaves of spinach (spinacia oleracea) was determined in two stages, stage 1, after five weeks of plant growth and stage 2, after 10 weeks with full growth. under the influence of contamination of soil with the heavy metal mixtures ... | 2004 | 15186035 |
| mid- to low-frequency fourier transform infrared spectra of s-state cycle for photosynthetic water oxidation in synechocystis sp. pcc 6803. | flash-induced fourier transform infrared (ftir) difference spectra for the four-step s-state cycle and the effects of global (15)n- and (13)c-isotope labeling on the difference spectra were examined for the first time in the mid- to low-frequency (1200-800 cm(-1)) as well as the mid-frequency (1700-1200 cm(-1)) regions using photosystem (ps) ii core particles from cyanobacterium synechocystis sp. pcc 6803. the difference spectra clearly exhibited the characteristic vibrational features for each ... | 2004 | 15182190 |
| the 26s proteasome in garlic (allium sativum): purification and partial characterization. | the 26s proteasome (multicatalytic protease complex, mpc) was purified from fresh garlic cloves (allium sativum) to near homogeneity by ion exchange chromatography on deae-sephacel, gel filtration on sepharose-4b, and glycerol density gradient centrifugation. two alpha-type (20s proteasome "catalytic core") subunits were identified by the direct sequencing of peptide fragments (mass fingerprint analysis, mass spectrometry lab, stanford university) or the sequencing of a cloned cdna generated usi ... | 2004 | 15161196 |
| acetyl coenzyme a concentrations in plant tissues. | despite the importance of acetyl coenzyme a in many facets of metabolism and the availability of methods for estimation of its concentration, data for acetyl-coa concentrations in plant tissues have been very scarce. a method using reversed phase hplc for the quantitative estimation of acetyl-coa was applied to a variety of plant tissues. in three different developing oilseeds the bulk acetyl-coa concentration ranged from 5 to 25 nmoles/g fresh weight. in arabidopsis thaliana leaves it was 5 nmo ... | 2004 | 15128036 |
| cytokinin stimulates polyribosome loading of nuclear-encoded mrnas for the plastid atp synthase in etioplasts of lupinus luteus: the complex accumulates in the inner-envelope membrane with the cf(1) moiety located towards the stromal space. | three of the nine subunits of the plastid atp synthase, including the subunit of the cf(1) moiety (gene atpc), are encoded in the nucleus. application of cytokinin to etiolated lupine seedlings induces polyribosome association of their mrnas. this appears to be specific as no such regulation was observed for messages for three ribosomal proteins. cytokinin-mediated polyribosome loading was also observed for the spinach atpc message in etiolated transgenic tobacco seedlings. analysis of various s ... | 2004 | 15125765 |
| ntzip antisense plants show reduced chlorophyll levels. | we have isolated and characterized a new photosynthetic tissue-specific gene ntzip (nicotiana tabacum leucine zipper) from tobacco (n. tabacum). its deduced amino acid sequence has two highly conserved regions, leucine zipper and [ex(n)dexrh](2) motifs, which are related to the gene's biochemical functions. ntzip was expressed in leaves and stems, but was not detected in roots or flowers, suggesting that its physiological functions might be associated with photosynthesis. northern blot analysis ... | 2004 | 15120117 |
| mechanism and importance of post-translational regulation of nitrate reductase. | in higher plants, nitrate reductase (nr) is inactivated by the phosphorylation of a conserved ser residue and binding of 14-3-3 proteins in the presence of divalent cations or polyamines. a transgenic nicotiana plumbaginifolia line (s521) has been constructed where the regulatory, conserved ser 521 of tobacco nr (corresponding to ser 534 in arabidopsis) was mutated into asp. this mutation resulted in the complete abolition of activation/inactivation in response to light/dark transitions or other ... | 2004 | 15107452 |
| time-resolved oxygen production by psii: chasing chemical intermediates. | photosystem ii (psii) produces dioxygen from water in a four-stepped process, which is driven by four quanta of light and catalysed by a mn-cluster and tyrosine z. oxygen is liberated during one step, coined s(3)=>s(0). chemical intermediates on the way from reversibly bound water to dioxygen have not yet been tracked, however, a break in the arrhenius plot of the oxygen-evolving step has been taken as evidence for its existence. we scrutinised the temperature dependence of (i) uv-absorption tra ... | 2004 | 15100031 |
| effects of composting on phytotoxicity of spent pig-manure sawdust litter. | the phytotoxicity of spent pig-manure sawdust litter (spent litter) was evaluated during further composting. aqueous extracts of the spent litter were prepared by shaking the sample with water (1:10 w/v), and the toxicity of these extracts was determined on relative seed germination, relative root elongation and germination index (gi, a factor of relative seed germination and relative root elongation). the sensitivity of six plant species, namely brassica parachinensis (chinese cabbage), brassic ... | 1996 | 15093523 |
| relationship between the heat tolerance of photosynthesis and the thermal stability of rubisco activase in plants from contrasting thermal environments. | inhibition of net photosynthesis (pn) by moderate heat stress has been attributed to an inability of rubisco activase to maintain rubisco in an active form. to examine this proposal, the temperature response of pn, rubisco activation, chlorophyll fluorescence, and the activities of rubisco and rubisco activase were examined in species from contrasting environments. the temperature optimum of rubisco activation was 10 degrees c higher in the creosote bush (larrea tridentata) compared with the ant ... | 2004 | 15084731 |
| antihypertensive properties of spinach leaf protein digests. | leaf protein containing approximately 50% rubisco (ribulose bisphosphate carboxylase/oxygenase) was obtained from fresh spinach leaf with the use of a simple extraction method. pepsin and pepsin-pancreatin digests of spinach leaf protein have potent angiotensin-i converting enzyme inhibitory properties with ic(50) values of 56 and 120 microg/ml, respectively. both digests of leaf protein have antihypertensive effects after oral administration to spontaneously hypertensive rats (shr) with minimum ... | 2004 | 15080624 |
| pre-extraction preparation (fresh, frozen, freeze-dried, or acetone powdered) and long-term storage of fruit and vegetable tissues: effects on antioxidant enzyme activity. | activities of the antioxidant enzymes ascorbate peroxidase, catalase, dehydroascorbate reductase, glutathione reductase, guaiacol peroxidase, monodehydroascorbate reductase, and superoxide dismutase were assayed in honeydew (cucumis melo l.) fruit and spinach (spinacia oleracea l.) leaves either as fresh, frozen to -80 degrees c, frozen in liquid nitrogen, freeze-dried, or acetone powder, representing the various ways tissues are treated prior to enzyme extraction. treated tissues were analyzed ... | 2004 | 15080616 |
| de-epoxidation of violaxanthin in light-harvesting complex i proteins. | the conversion of violaxanthin (vx) to zeaxanthin (zx) in the de-epoxidation reaction of the xanthophyll cycle plays an important role in the protection of chloroplasts against photooxidative damage. vx is bound to the antenna proteins of both photosystems. in photosystem ii, the formation of zx is essential for the ph-dependent dissipation of excess light energy as heat. the function of zx in photosystem i is still unclear. in this work we investigated the de-epoxidation characteristics of ligh ... | 2004 | 15070896 |
| functional expression of a delta12 fatty acid desaturase gene from spinach in transgenic pigs. | linoleic acid (18:2n-6) and alpha-linolenic acid (18:3n-3) are polyunsaturated fatty acids that are essential for mammalian nutrition, because mammals lack the desaturases required for synthesis of delta12 (n-6) and n-3 fatty acids. many plants can synthesize these fatty acids and, therefore, to examine the effects of a plant desaturase in mammals, we generated transgenic pigs that carried the fatty acid desaturation 2 gene for a delta12 fatty acid desaturase from spinach. levels of linoleic aci ... | 2004 | 15067141 |
| synthesis of pyrazole derivatives and their evaluation as photosynthetic electron transport inhibitors. | two series of new pyrazoles, namely six pyrazolo[1,5-a][1,3,5]triazine-2,4-dione and four pyrazolo[1,5-c][1,3,5]thiadiazine-2-one derivatives, were synthesized as potential inhibitors of the photosynthetic electron transport chain at the photosystem ii level. the compounds were confirmed by 1h nmr, elemental, and ir analyses. their biological activity was evaluated in vivo upon both the growth of blue-green algae and the photosynthetic oxygen evolution by eukaryotic algae and in vitro as the abi ... | 2004 | 15053526 |
| comparative analysis of isolated cellular organelles by means of soft x-ray contact microscopy with laser-plasma source and transmission electron microscopy. | soft x-ray contact microscopy (sxcm) is, at present, a useful tool for the examination at submicrometre resolution of biological systems maintained in their natural hydrated conditions. among current x-ray-generating devices, laser-plasma sources are now easily available and, owing to their pulse nature, offer the opportunity to observe living biological samples before radiation damage occurs, even if the resolution achievable is not as high as with synchrotron-produced x-rays. to assess the pot ... | 2004 | 15049867 |
| [determination of low-level pesticide residues in agricultural products by ion-trap gc/ms/ms]. | the objective of this study was to elucidate the utility of ion-trap gc/ms/ms for the analysis of pesticides in extracted matrices from various agricultural products. identification and quantitative analysis of pesticides in matrices were performed by quadrupole gc/ms and ion-trap gc/ms/ms. chlorpyrifos was added to the matrix of spinach, soybean in the pod or corn, and aldrin, dieldrin, endrin, alpha-bhc, beta-bhc, gamma-bhc, delta-bhc, p,p'-ddd, p,p'-dde, o,p'-ddt and p,p'-ddt were added to ea ... | 2003 | 15038113 |
| fractional magnesium absorption is significantly lower in human subjects from a meal served with an oxalate-rich vegetable, spinach, as compared with a meal served with kale, a vegetable with a low oxalate content. | the aim of the present study was to evaluate mg absorption from a test meal served with an oxalate-rich vegetable, spinach, as compared with a test meal served with a vegetable with a low oxalate content, kale. mg absorption was measured by a stable-isotope technique based on extrinsic labelling of the test meals and faecal monitoring of the excreted isotope labels. nine healthy adults participated in the study. the test meals were based on 100 g phytate-free white bread, served with 300 g spina ... | 2004 | 15035687 |
| cloning and salt-induced, aba-independent expression of choline mono-oxygenase in atriplex prostrata. | certain plants accumulate glycinebetaine, a type of osmoprotectant, in response to salinity. glycinebetaine is synthesized in these plants via the two-step oxidation of choline, and the first step is catalysed by choline mono-oxygenase (cmo; ec 1.14.15.7). cloned by rt-pcr and 3'-race, the cdna of atriplex prostrata cmo (apcmo) is 1669 bp in length and encodes a full-length protein of 438 amino acids. the deduced amino acid sequence of apcmo revealed a rieske-type [2fe-2s] cluster motif and a mo ... | 2004 | 15032837 |
| the oxygen evolving enhancer protein 1 (oee) of photosystem ii in green algae exhibits thioredoxin activity. | a thioredoxin-like chloroplast protein of the fructosebisphosphatase-stimulating f-type, but with an unusually high molecular mass of 28 kda has previously been identified and purified to homogeneity in a fractionation scheme for resolution of the acid- and heat-stable, regular-size (12kda) thioredoxins of the unicellular green algae, scenedesmus obliquus. an apparently analogous protein of 26 kda was described in a cyanobacterium, anabaena sp., but no such large thioredoxin species f exists in ... | 2004 | 15022827 |
| identification of domains on the extrinsic 23 kda protein possibly involved in electrostatic interaction with the extrinsic 33 kda protein in spinach photosystem ii. | to elucidate the domains on the extrinsic 23 kda protein involved in electrostatic interaction with the extrinsic 33 kda protein in spinach photosystem ii, we modified amino or carboxyl groups of the 23 kda protein to uncharged methyl ester groups with n-succinimidyl propionate or glycine methyl ester in the presence of a water-soluble carbodiimide, respectively. the n-succinimidyl propionate-modified 23 kda protein did not bind to the 33 kda protein associated with psii membranes, whereas the g ... | 2004 | 15009208 |
| thioredoxin links redox to the regulation of fundamental processes of plant mitochondria. | mitochondria contain thioredoxin (trx), a regulatory disulfide protein, and an associated flavoenzyme, nadp/trx reductase, which provide a link to nadph in the organelle. unlike animal and yeast counterparts, the function of trx in plant mitochondria is largely unknown. accordingly, we have applied recently devised proteomic approaches to identify soluble trx-linked proteins in mitochondria isolated from photosynthetic (pea and spinach leaves) and heterotrophic (potato tubers) sources. applicati ... | 2004 | 14983062 |
| functional consequences of n- or c-terminal deletions of the delta subunit of chloroplast atp synthase. | mutagenesis was used to generate seven truncation mutants of the spinach (spinacia oleracea) chloroplast atp synthase delta subunit lacking 5, 11, 17, or 35 amino acid residues from the n-terminus or 3, 9, or 15 residues from the c-terminus. interactions between these mutants and all other subunits of the chloroplast atpase were investigated by a yeast two-hybrid system. the results indicate that the n-terminal deletions mainly affected interactions between the delta subunit and the other part o ... | 2004 | 14979723 |
| poplar peroxiredoxin q. a thioredoxin-linked chloroplast antioxidant functional in pathogen defense. | peroxiredoxins are ubiquitous thioredoxin- or glutaredoxin-dependent peroxidases, the function of which is to destroy peroxides. peroxiredoxin q, one of the four plant subtypes, is a homolog of the bacterial bacterioferritin comigratory proteins. we show here that the poplar (populus tremula x populus tremuloides) protein acts as a monomer with an intramolecular disulfide bridge between two conserved cysteines. a wide range of electron donors and substrates was tested. unlike type ii peroxiredox ... | 2004 | 14976238 |
| arsenic availability from chromated copper arsenate (cca)-treated wood. | lumber used to construct raised garden beds is often treated with chromated copper arsenate (cca). this project aimed to determine (i) how far as, cu, and cr had diffused away from cca-treated wood surfaces in raised garden beds under realistic conditions, (ii) the uptake of these elements by crops, and (iii) the effect of cca solution on soil bacteria. this study showed that as, cu, and cr diffuse into soil from cca-treated wood used to construct raised garden beds. to determine crop uptake of ... | 2013 | 14964372 |
| oxidation-reduction properties of maize ferredoxin: sulfite oxidoreductase. | oxidation-reduction titrations have been carried out on the wild-type, ferredoxin-dependent sulfite reductase from maize and two site-specific variants of the enzyme. e(m) values have been determined for the siroheme and [4fe-4s] cluster prosthetic groups of the enzyme, which titrate as independent, one-electron carriers. visible-region difference spectra suggest that reduction of the [4fe-4s] cluster significantly perturbs the spectrum of the reduced siroheme group of the enzyme. the effects of ... | 2004 | 14871491 |
| comparison of survival of campylobacter jejuni in the phyllosphere with that in the rhizosphere of spinach and radish plants. | campylobacter jejuni has been isolated previously from market produce and has caused gastroenteritis outbreaks linked to produce. we have tested the ability of this human pathogen to utilize organic compounds that are present in leaf and root exudates and to survive in the plant environment under various conditions. carbon utilization profiles revealed that c. jejuni can utilize many organic acids and amino acids available on leaves and roots. despite the presence of suitable substrates in the p ... | 2004 | 14766604 |
| on the export of fatty acids from the chloroplast. | the model for export of fatty acids from plastids proposes that the acyl-acp (acyl carrier protein) product of de novo fatty acid synthesis is hydrolyzed in the stroma by acyl-acp thioesterases and the free fatty acid (ffa) released is then transferred to the outer envelope of the plastid where it is reactivated to acyl-coa for utilization in cytosolic glycerolipid synthesis. experiments were performed to assess whether the delivery of nascent ffa from the stroma for long chain acyl-coa synthesi ... | 2004 | 14764601 |
| seasonal prevalence and susceptibility to agrochemicals of tyrophagus similis (acari: acaridae) in spinach buds and agricultural soil under greenhouse conditions. | seasonal prevalence of tyrophagus similis was investigated from 1997 to 1998 in two spinach greenhouses in central japan. susceptibility of t. similis to agrochemicals was also tested in the laboratory. tyrophagus similis density in the soil was low during the high temperature period from may to august. the density rapidly increased in late autumn and remained at a high level during the cool season from december to february. the number further increased in april and then rapidly decreased in may ... | 2003 | 14756393 |
| ftir spectroscopy shows structural similarities between photosystems ii from cyanobacteria and spinach. | photosystem ii (psii), an essential component of oxygenic photosynthesis, is a membrane-bound pigment protein complex found in green plants and cyanobacteria. whereas the molecular structure of cyanobacterial psii has been resolved with at least medium resolution [zouni, a., witt, h.-t., kern, j., fromme, p., krauss, n., saenger, w. & orth, p. (2001) nature (london) 409, 739-743; kamiya, n. & shen, j.r. (2003) proc. natl acad. sci. usa 100, 98-103], the structure of higher plant psii is only kno ... | 2004 | 14728683 |
| mechanism of spinach chloroplast ferredoxin-dependent nitrite reductase: spectroscopic evidence for intermediate states. | nitrite reductases found in plants, algae, and cyanobacteria catalyze the six-electron reduction of nitrite to ammonia with reduced ferredoxin serving as the electron donor. they contain one siroheme and one [4fe-4s] cluster, acting as separate one-electron carriers. nitrite is thought to bind to the siroheme and to remain bound until its complete reduction to ammonia. in the present work the enzyme catalytic cycle, with ferredoxin reduced by photosystem 1 as an electron donor, has been studied ... | 2004 | 14717606 |
| composition, efficacy, and safety of spinach extracts. | spinach leaves, containing several active components, including flavonoids, exhibit antioxidative, antiproliferative, and antiinflammatory properties in biological systems. spinach extracts have been demonstrated to exert numerous beneficial effects, such as chemo- and central nervous system protection and anticancer and antiaging functions. in this review article, we present a compilation of data generated in our laboratories and those of other investigators describing the chemical composition ... | 2003 | 14690799 |
| substrate recognition and selectivity of plant glycerol-3-phosphate acyltransferases (gpats) from cucurbita moscata and spinacea oleracea. | stromal glycerol-3-phosphate acyltransferases (gpat) are responsible for the selective incorporation of saturated and unsaturated fatty-acyl chains into chloroplast membranes, which is an important determinant of a plant's ability to tolerate chilling temperatures. the molecular mechanisms of plant chilling tolerance were elucidated by creating chimeric gpats between squash (cucurbita moscata, chilling-sensitive) and spinach (spinacea oleracea, chilling-tolerant) and the results were interpreted ... | 2004 | 14684887 |