| polypeptides of the oxygen-evolving photosystem ii complex. immunological detection and biogenesis. | oxygen-evolving photosystem ii complex was isolated from spinach chloroplasts. the individual polypeptides of the complex were isolated from sodium dodecyl sulfate (sds)-polyacrylamide gels and antibodies were raised in rabbits against these polypeptides. after washing of the isolation complex by 0.8 m tris to release the extrinsic proteins, a distinct diffused protein band was revealed at the position of 33 kda in sds gels containing 4 m urea. when this band was electroeluted from the gel and s ... | 1986 | 3514615 |
| amino acid sequence of copper,zinc-superoxide dismutase from spinach leaves. | the complete amino acid sequence of cu,zn-superoxide dismutase (sod) from spinach leaves has been determined on the basis of peptides obtained by cyanogen bromide (brcn) cleavage and by enzymic hydrolyses with achromobacter lyticus lysylendopeptidase, staphylococcus aureus v8 protease, trypsin, and thermolysin. the spinach sod consists of a total of 154 amino acid residues with alanine as the amino(n)-terminus and valine as the carboxy(c-)terminus. the present sequence, which has been establishe ... | 1986 | 3519601 |
| mapping of the triazine binding site to a highly conserved region of the qb-protein. | a number of herbicide classes, including the s-triazines and ureas (atrazine, diuron) inhibit photosynthetic electron transport via a direct interaction with the qb-protein. this protein, also known as the 32-kda protein or herbicide binding protein, is believed to bind the plastoquinone qb, which functions as the second stable electron acceptor at the reducing side of photosystem ii. the site of covalent attachment of the photoaffinity herbicide analog azido-[14c]atrazine to the qb-protein of s ... | 1986 | 3524461 |
| partial purification and characterization of an insulin-like material from spinach and lemna gibba g3. | the existence in invertebrates, unicellular eukaryotes, and prokaryotes of materials that resemble several vertebrate peptide hormones led to the suggestion that these peptide messengers may have arisen earlier in evolution than had previously been thought. consistent with this hypothesis, we describe here material in two plants, spinach and lemma gibba g3, that is very similar to mammalian insulin, yet distinctive. in each of the early purification steps, which consisted of acidic methanol chlo ... | 1987 | 3553187 |
| enumeration and characterization of aeromonas hydrophila and aeromonas caviae isolated from grocery store produce. | starch-ampicillin agar was used to quantitatively isolate aeromonas sp. from retail grocery store produce. all produce sampled, including parsley, spinach, celery, alfalfa sprouts, broccoli, and lettuce, contained aeromonas sp. in most instances, the count of aeromonas sp. increased 10- to 1,000-fold during 2 weeks of storage at 5 degrees c. eleven (92%) of 12 kinds of produce yielded cytotoxic aeromonas sp. identification as aeromonas hydrophila was the strongest indicator of cytotoxicity, and ... | 1987 | 3566266 |
| the nature of l8 and l8s8 forms of ribulose bisphosphate carboxylase/oxygenase from chromatium vinosum. | l8 and l8s8 forms of ribulose bisphosphate carboxylase/oxygenase (rubisco) have been prepared from chromatium vinosum by the extremely mild method of centrifugal fractionation. only the l8s8 form is detectable in crude extracts of this organism. both forms show immunological identify in double diffusion studies using antibody to l subunits of the l8s8 form. l subunits from both l8 and l8s8 enzymes are identical by the criteria of peptides observed after limited proteolysis and n-terminal sequenc ... | 1987 | 3579306 |
| rare-earth elements in the nbs standard reference materials spinach, orchard leaves, pine needles and bovine liver. | a highly sensitive radiochemical neutron activation method for the determination of all rare-earth elements (ree) in nbs biological reference materials is described. the materials are irradiated, dissolved in hf/hcl solutions, mixed with scandium and ree carriers (except la, pr, nd, dy, er), and the resulting solutions evaporated to dryness. the residues are dissolved in hcl and the ree precipitated as fluorides on addition of hf/nh4f solutions. the ree fluorides were collected, dissolved in a n ... | 1987 | 3589659 |
| simplified cleanup and gas chromatographic determination of organophosphorus pesticides in crops. | a simple and efficient cleanup method for gas chromatographic determination of 23 organophosphorus pesticides in crops including onion is described. the sample was extracted with acetone. the extract was purified with coagulating solution, which contained ammonium chloride and phosphoric acid, and then filtered by suction. the filtrate was diluted with nacl solution and reextracted with benzene. the organic layer was evaporated and injected into a gas chromatograph equipped with a flame photomet ... | 1987 | 3610958 |
| the determination of glutathione, cyst(e)ine, and other thiols and disulfides in biological samples using high-performance liquid chromatography with dual electrochemical detection. | a determination of glutathione, cysteine, and their disulfides using hplc and dual electrochemical detection (hplc-dec) was described previously but was not validated in biological tissues for these and other important thiols and disulfides (sh/ss). thus, our objectives were to develop this method to quantify simultaneously reduced and oxidized glutathione, cysteine, cystine, and other sh/ss in various tissues, including human blood and plasma, rat liver and hippocampus, mosquito, and spinach le ... | 1987 | 3619033 |
| oxalic acid decreases calcium absorption in rats. | calcium absorption from salts and foods intrinsically labeled with 45ca was determined in the rat model. calcium bioavailability was nearly 10 times greater for low oxalate kale, caco3 and cacl2 than from cac2o4 (calcium oxalate) and spinach (high in oxalates). extrinsic and intrinsic labeling techniques gave a similar assessment of calcium bioavailability from kale but not from spinach. | 1987 | 3681480 |
| extraction of proteins and membrane lipids during low temperature embedding of biological material for electron microscopy. | the extraction of proteins and membrane lipids from biological materials during embedding procedures for electron microscopy carried out at temperatures down to 223 k was studied. glutaraldehyde-fixed cells of acholeplasma laidlawii mainly served as test material. more than 99% of the protein and 88% of the lipid of these cells were retained after dehydration with ethanol or acetone between 277 and 223 k and infiltration with methacrylate at 223 k. when methanol was used for dehydration, only 54 ... | 1986 | 3712423 |
| transient kinetics of reduction of blue copper proteins by free flavin and flavodoxin semiquinones. | rate constants have been determined for the electron-transfer reactions between reduced free flavins and flavodoxin semiquinone and several blue copper proteins. correlations between these values and redox potentials demonstrate that spinach plastocyanin, pseudomonas aeruginosa azurin, alcaligenes sp. azurin, and alcaligenes sp. nitrite reductase have the same intrinsic reactivities toward free flavins, whereas stellacyanin is more reactive (3.3 times) and laccase considerably less reactive (app ... | 1986 | 3730365 |
| immunological studies of the binding protein for chloroplast ferredoxin-nadp+ reductase. | monospecific rabbit antibodies against the ferredoxin-nadp+ reductase binding protein of spinach thylakoids were obtained and characterized. the immunoglobulin g (igg) fraction gave single precipitation arcs with the purified antigen or with triton x-100 extracts of thylakoids or the reductase binding protein complex. antibodies against the flavoprotein behave similarly. both antibodies agglutinated thylakoids and precipitated the diaphorase activity of a triton x-100 extract of these membranes. ... | 1987 | 3813568 |
| in vitro expression of chloroplast genes in lysates of higher plant chloroplasts. | a dna-dependent in vitro-coupled transcription-translation system has been prepared from lysates of isolated chloroplasts. these lysates are comparable to those of escherichia coli in transcriptional and translational fidelity and efficiency in response to a given template dna. when nicotiana tabacum chloroplast dna is used as template with chloroplast lysates (n. tabacum or spinach) or e. coli lysates, nadodso4 gel analysis reveals similar polypeptide patterns that are distinct from the pattern ... | 1985 | 3858855 |
| characterization of an active-site peptide modified by glyoxylate and pyridoxal phosphate from spinach ribulosebisphosphate carboxylase/oxygenase. | activated ribulosebisphosphate carboxylase/oxygenase from spinach was treated with glyoxylate plus or minus the transition-state analog, carboxyarabinitol bisphosphate, or the inactive enzyme with pyridoxal phosphate plus or minus the substrate, ribulose bisphosphate. covalently modified adducts with glyoxylate or pyridoxal phosphate were formed following reduction with sodium borohydride. the derivatized enzymes were carboxymethylated and digested with trypsin; the labeled peptides which were u ... | 1985 | 3860189 |
| organization and sequence of five trna genes and of an unidentified reading frame in the wheat chloroplast genome: evidence for gene rearrangements during the evolution of chloroplast genomes. | the genes for the initiator trna(met)cau, trna(gly)ucc, trna(thr)ggu, trna(glu)uuc and trna(tyr)gua and an open reading frame of 62 codons have been identified by sequencing a 2,358 bp bamhi and a 1,378 bp bamhi-sst2 dna fragments from wheat chloroplasts. a comparison of the organization of these five trna genes and of the open reading frame on the wheat, tobacco and spinach chloroplast genomes suggests that at least three genomic inversions must have occurred during the evolution of the wheat c ... | 1985 | 3870931 |
| the primary structure of ribosomal protein l2 from bacillus stearothermophilus. | the complete amino acid sequence of ribosomal protein l2 from the moderate thermophile bacillus stearothermophilus has been determined. this has been achieved by the sequence analysis of peptides derived by enzymatic digestion with staphylococcus aureus protease, trypsin and chymotrypsin, as well as by chemical cleavage with o-iodosobenzoic acid. the protein contains 275 amino acid residues and has a calculated molecular mass of 30201 da. comparison of this sequence with sequences of the corresp ... | 1985 | 3908098 |
| subunit dissociation and reconstitution of ribulose-1,5-bisphosphate carboxylase from chromatium vinosum. | the large and small subunits of ribulose bisphosphate carboxylase from chromatium vinosum were dissociated and separated at ph 9.6 by sucrose density gradient centrifugation. after further purification by gel filtration, the small subunit fraction contained no carboxylase activity. the large subunit fraction was highly depleted of small subunit based on analysis by denaturing polyacrylamide gel electrophoresis. carboxylase activity of the large subunit fraction was approximately 1% of the untrea ... | 1985 | 3918498 |
| catalytic properties of a hybrid between cyanobacterial large subunits and higher plant small subunits of ribulose bisphosphate carboxylase-oxygenase. | the small subunits of spinach ribulosebisphosphate carboxylase-oxygenase were isolated by mild acid precipitation of the hexadecameric holoenzyme. about one-third of the small subunits remained in the supernatant while the remainder, and all of the large subunits, were precipitated and irreversibly denatured. the spinach small subunits were able to reassemble with the large subunit octamer of ribulosebisphosphate carboxylase-oxygenase from the cyanobacterium, synechococcus acmm 323, prepared as ... | 1985 | 3921534 |
| carbon isotope effect on carboxylation of ribulose bisphosphate catalyzed by ribulosebisphosphate carboxylase from rhodospirillum rubrum. | the carbon isotope effect at co2 has been measured in the carboxylation of ribulose 1,5-bisphosphate by the ribulosebisphosphate carboxylase from rhodospirillum rubrum. the isotope effect is obtained by comparing the isotopic composition of carbon 1 of the 3-phosphoglyceric acid formed in the reaction with that of the carbon dioxide source. a correction is made for carbon 1 of 3-phosphoglyceric acid which arises from carbon 3 of the starting ribulose bisphosphate. the isotope effect is k12/k13 = ... | 1985 | 3924094 |
| ionization constants of two active-site lysyl epsilon-amino groups of ribulosebisphosphate carboxylase/oxygenase. | trinitrobenzene sulfonate rapidly inactivates ribulosebisphosphate carboxylase/oxygenase from both spinach and rhodospirillum rubrum. with large molar excesses of the reagent, the reactions obey pseudo-first order kinetics and the rates of inactivations are directly proportional to the concentrations of trinitrobenzene sulfonate; thus, there is no indication of reversible complexation of reagent with enzyme. saturating levels of the competitive inhibitor 2-carboxyribitol 1,5-bisphosphate reduce ... | 1985 | 3932347 |
| the euglena gracilis chloroplast ribulose-1,5-bisphosphate carboxylase gene. ii. the spliced mrna and its product. | the polypeptide product of the gene for the large subunit of ribulose-1,5-bisphosphate carboxylase from euglena gracilis based on the dna sequence of the chloroplast-encoded gene is described. the large subunit polypeptide of 475 codons is co-linear with the homologous polypeptides from other chloroplasts and cyanobacteria. the amino acid sequence is 92% homologous to that of chlamydomonas, 84% homologous to spinach, 82% homologous to maize, and 80% homologous to that of the cyanobacterium anaba ... | 1985 | 3934171 |
| the sulfhydryl groups of ferredoxin-nadp+ oxidoreductases: is a disulfide bond really present? | the sulfhydryl groups of three ferredoxin-nadp+ oxidoreductases [ec 1.18.1.2] (fnr) two from blue-green algae, spirulina sp. and synechococcus sp., respectively, and one from spinach, were analyzed by carboxymethylation and titration with sulfhydryl reagents under different conditions. five sulfhydryl groups in spirulina and spinach enzymes and four in synechococcus enzyme were found to be in reduced forms. there was no disulfide bond in any fnr tested. the results in the present experiment cont ... | 1985 | 3935649 |
| efficacy of the rat bioassay for the determination of biologically available vitamin b-6. | research was conducted to evaluate the merits of rat bioassays in studies concerning the bioavailability of vitamin b-6. a protocol was devised, which included pair-feeding and prevention of coprophagy. plasma pyridoxal 5'-phosphate (plp) was measured by a rapid chromatographic method as an indicator of vitamin b-6 status. pyridoxamine and pyridoxal exhibited 70% molar activity relative to pyridoxine at suboptimal dietary levels. selected foods (spinach, cornmeal and potato) were evaluated at th ... | 1986 | 3944659 |
| synthesis of large subunit of ribulosebisphosphate carboxylase by thylakoid-bound polyribosomes from spinach chloroplasts. | intact chloroplasts were isolated from developing first leaves of spinach. the chloroplasts were broken and separated into an extensively washed membrane (thylakoid) fraction and a soluble (stroma) fraction. the membrane fraction contained polyribosomes with properties similar to those of thylakoid-bound polyribosomes of other organisms. the distribution of mrna for large-subunit ribulosebisphosphate carboxylase (ls) was determined by translating rna from chloroplasts, thylakoids, and stroma in ... | 1986 | 3947083 |
| new crystal forms of ribulose-1,5-bisphosphate carboxylase/oxygenase from rhodospirillum rubrum. | three crystal forms of the dimeric form of the enzyme ribulose-1,5-bisphosphate carboxylase from the photosynthetic bacterium rhodospirillum rubrum have been obtained from the gene product expressed in escherichia coli. form a crystals formed from the quaternary complex comprising enzyme-activator carbamate-mg2+-2'-carboxyarabinitol-1,5-bisphosphate are shown here to be devoid of ligands. in contrast, crystals of the quaternary complex formed with the hexadecameric l8s8 enzyme from spinach conta ... | 1986 | 3959081 |
| kinetics of reduction of clostridium pasteurianum rubredoxin by laser photoreduced spinach ferredoxin:nadp+ reductase and free flavins. electron transfer within a protein-protein complex. | the kinetics of reduction of oxidized clostridium pasteurianum rubredoxin (rdox) by free flavin semiquinones generated by the laser flash photolysis technique and by spinach ferredoxin:nadp+ reductase (fnr) semiquinone (also produced by flavin semiquinone reduction) have been investigated under anaerobic conditions. 5-deazariboflavin semiquinone (5-drf) rapidly reduces oxidized rubredoxin (rdox) (k = 3.0 x 10(8) m-1 s-1) and oxidized ferredoxin:nadp+ reductase (fnrox) to the semiquinone level (k ... | 1985 | 3968079 |
| a reappraisal of leukocyte dehydroascorbate reductase. | dehydroascorbate reductase (glutathione:dehydroascorbate oxidoreductase, ec 1.8.5.1) activity was determined in human leukocyte homogenates using a direct spectrophotometric assay. despite previous studies, using a less sensitive coupled assay, which reported that this enzyme was present in leukocytes, we found that neither neutrophil nor chronic lymphocytic leukemia lymphocyte extracts had detectable activity. furthermore, when the product was quantitated by hplc, protein-dependent generation c ... | 1985 | 3978119 |
| isolation and characterization of safflower (carthamus tinctorius l.) chloroplast dna. | safflower (carthamus tinctorius l.) chloroplasts were isolated and purified with the aid of commercially available nylon mesh, differential centrifugation, and dnase i treatment. these chloroplasts were free of nuclei as determined by light microscopy of aceto orcein stained preparations, and similar to those observed by electron microscopy in spinach and many other higher plants, being bounded by a double membrane layer and characterized by the presence of a lamellar system surrounded by embedd ... | 1985 | 3982399 |
| localization of phosphatidylcholine in outer envelope membrane of spinach chloroplasts. | we have examined the effects of phospholipase c from bacillus cereus on the extent of phospholipid hydrolysis in envelope membrane vesicles and in intact chloroplasts. when isolated envelope vesicles were incubated in presence of phospholipase c, phosphatidylcholine and phosphatidylglycerol, but not phosphatidylinositol, were totally converted into diacylglycerol if they were available to the enzyme (i.e., when the vesicles were sonicated in presence of phospholipase c). these experiments demons ... | 1985 | 3988805 |
| trace element solubility from food following enzymolysis. | food items were treated with enzymes simulating gastric and intestinal digestive juices and the amounts of soluble lead, cadmium, zinc, iron, and copper, were determined. enzyme treatment was conducted in two stages involving (i) pepsin at ph 2,5 followed by (ii) pancreatin and amylase at neutral ph. solubility was determined after each stage and additionally after post enzymolysis acidification. the foods examined comprised wholemeal bread, spinach, canned tomato, ox liver, pig kidney, canned c ... | 1985 | 4002861 |
| biosynthesis of sulfoquinovosyldiacylglycerol in higher plants: the origin of the diacylglycerol moiety. | the positional distribution of fatty acids in chloroplast polar lipids and phosphatidylcholine from leaves of four plants has been measured in order to determine the origin of the diacylglycerol (dag) moieties of each lipid. in spinach and tobacco, the dag of sulfoquinovosyldiacylglycerol (sqdg), monogalactosyldiacylglycerol (mgdg) and digalactosylglycerol (dgdg) were derived partly from the chloroplast and partly from the cytoplasm. the contribution of the chloroplast pathway differed for each ... | 1985 | 4026308 |
| isolation of l8 and l8s8 forms of ribulose bisphosphate carboxylase/oxygenase from chromatium vinosum. | the enzyme ribulose bisphosphate carboxylase/oxygenase has been purified from chromatium vinosum. when an extract is subjected to centrifugation at 35,000 x g in the presence of polyethylene glycol (peg)-6000 and the supernatant is treated with 50 mm mg2+ and the precipitate is then fractionated by vertical centrifugation into a reoriented sucrose gradient followed by chromatography on diethylaminoethyl (deae)-sephadex a50, the resultant enzyme contains large (l) and small (s) subunits. alternat ... | 1985 | 4037978 |
| purification and characterization of ferredoxin-nicotinamide adenine dinucleotide phosphate reductase from a nitrogen-fixing bacterium. | evidence suggesting that bacillus polymyxa has an active ferredoxin-nadp(+) reductase (ec 1.6.99.4) was obtained when nadph was found to provide reducing power for the nitrogenase of this organism; direct evidence was provided when it was shown that b. polymyxa extracts could substitute for the native ferredoxin-nadp(+) reductase in the photochemical reduction of nadp(+) by blue-green algal particles. the ferredoxin-nadp(+) reductase was purified about 80-fold by a combination of high-speed cent ... | 1973 | 4147648 |
| absorption of chlorophyll phytol in normal man and in patients with refsum's disease. | this study was made to determine the extent of absorption of chlorophyll phytol from the intestine of man, and the importance of chlorophyll as a source of the phytanic acid that accumulates in refsum's disease. uniformly (14)c-labeled pheophytin a (the mg-free derivative of chlorophyll a) was fed to normal human subjects and to patients with refsum's disease. feces were collected and analyzed. in all subjects, 90-95% of the administered radioactivity was recovered in the feces, still largely in ... | 1968 | 4177872 |
| interaction of spinach leaf adenosine diphosphate glucose alpha-1,4-glucan alpha-4-glucosyl transferase and alpha-1,4-glucan, alpha-1,4-glucan-6-glycosyl transferase in synthesis of branched alpha-glucan. | | 1974 | 4208773 |
| studies on spinach leaf ribulosebisphosphate carboxylase. carboxylase and oxygenase reaction examined by immunochemical methods. | | 1974 | 4208775 |
| reconstitution of spinach ribulose-1,5-diphosphate carboxylase from departed subunits. | | 1974 | 4212305 |
| spinach leaf phosphoenolpyruvate carboxylase: purification, properties, and kinetic studies. | | 1974 | 4212347 |
| partial resolution of the enzymes catalyzing photophosphorylation. 8. properties of isolated subunits of coupling factor 1 from spinach chloroplasts. | | 1973 | 4266137 |
| spectroscopic studies on spinach ferredoxin and adrenodoxin. | | 1967 | 4292055 |
| studies on ferrochelatase. the enzymic formation of haem in proplastids, chloroplasts and plant mitochondria. | 1. ferrochelatase was demonstrated in the chloroplasts and proplastids isolated from the primary leaves of beans (a dicotyledon) and oats (a monocotyledon). it was also detected in chloroplasts from etiolated bean seedlings made green by illumination before being harvested. the specific activities of the three types of bean organelles are similar, as are the specific activities of the oat proplastids and chloroplasts. 2. chloroplasts from young spinach leaves also contain ferrochelatase; these c ... | 1968 | 4298995 |
| purification and separation of alpha- and beta-galactosidases from spinach leaves. | | 1970 | 4315053 |
| renaturation of spinach leaf glyoxylic acid reductase. | | 1970 | 4321767 |
| ferredoxin-activated fructose diphosphatase of spinach chloroplasts. resolution of the system, properties of the alkaline fructose diphosphatase component, and physiological significance of the ferredoxin-linked activation. | | 1971 | 4330061 |
| the iron electron-nuclear double resonance (endor) of two-iron ferredoxins from spinach, parsley, pig adrenal cortex and pseudomonas putida. | | 1971 | 4331268 |
| the two-iron ferredoxins in spinach, parsley, pig adrenal cortex, azotobacter vinelandii, and clostridium pasteurianum: studies by magnetic field mössbauer spectroscopy. | | 1971 | 4331269 |
| tetrahedral iron in the active center of plant ferredoxins and beef adrenodoxin. | the coordination structure of the iron-sulfur complex in spinach ferredoxin and adrenodoxin is investigated by optical spectroscopy. the circular-dichroism and absorption spectra of these two-iron iron-sulfur proteins reveal weak electronic transitions in the near-infrared wavelength range, 0.8-2.5 mum (12,500-4000 cm(-1)). on the basis of the low absorption intensities and large anisotropy factors, d --> d transitions of the iron can be identified in the reduced proteins at about 4000 cm(-1) an ... | 1971 | 4332004 |
| the expression of catechol oxidase activity during the hydroxylation of p-coumaric acid by spinach-beet phenolase. | 1. the conditions under which oxygen consumption in excess of that required for the hydroxylation of p-coumaric acid to caffeic acid, catalysed by spinach-beet phenolase, can be suppressed, have been examined. 2. with dimethyltetrahydropteridine as electron donor, oxygen uptake was exactly equivalent to the caffeic acid produced, provided that p-coumaric acid was in excess, but with excess of reductant, oxygen uptake caused by the further oxidation of caffeic acid was also observed. 3. with equa ... | 1972 | 4346745 |
| isolation of intact spinach chloroplasts in the cf-6 continuous-flow zonal rotor; implications for membrane-bound organelles. | | 1973 | 4353532 |
| structural analysis of phosphatidylcholine of plant tissue. | pure preparations of phosphatidylcholine were isolated from spinach leaf chloroplasts, spinach leaf microsomes, and cauliflower inflorescence. the isolated phosphatidylcholine was treated with snake venom phospholipase a, and the fatty acid distribution and composition of the fatty acid methyl esters prepared from the lysophosphatidylcholine and the freed fatty acid were determined by gas-liquid chromatography. the results showed that saturated fatty acids were preferentially esterified at posit ... | 1971 | 4362139 |
| oxidative decarboxylation of glycollate and glyoxylate by leaf peroxisomes. | 1. the conditions under which peroxisomal preparations from leaves of spinach beet and spinach catalyse the release of (14)co(2) from [1-(14)c]glycollate and [1-(14)c]glyoxylate were investigated. 2. at ph8, (14)co(2) production from [1-(14)c]glyoxylate was accompanied by equivalent quantities of formate. the accumulation of oxalate and the effects of various reagents, especially catalase inhibitors, show that glyoxylate is non-enzymically oxidized by h(2)o(2), which is generated by the oxidatio ... | 1974 | 4362741 |
| soluble & membrane-bound superoxide dismutases in a blue-green algae (spirulina)and spinach. | | 1974 | 4364622 |
| biosynthesis of nitrogenous phospholipids in spinach leaves. | | 1974 | 4367462 |
| the purification and properties of nitrite reductase from higher plants, and its dependence on ferredoxin. | 1. nadph-dependent nitrite reductase from the leaves of higher plants was purified at least 70-fold and separated into two enzyme fractions. the first enzyme, a diaphorase with ferredoxin-nadp-reductase activity, is required only to transfer electrons from nadph to a suitable electron acceptor, which then donates electrons to nitrite reductase proper. 2. purified nitrite reductase accepted electrons from ferredoxin (the natural donor) or from reduced dyes. ferredoxin was reduced by illuminated c ... | 1966 | 4381617 |
| d-glyceraldehyde 3-phosphate dehydrogenases of higher plants. | the d-glyceraldehyde 3-p dehydrogenases of spinach leaf, pea seed, and pea shoot were purified. the nadp and nad-linked enzymes of either spinach leaves and pea shoots could not be separated. changes in the ratio of nadp- to nad-linked activity of the spinach leaf and pea shoot enzymes were observed during both purification and storage of crude extracts. the spinach leaf, pea shoot, and pea seed enzymes differ electrophoretically from each other and from the rabbit muscle enzyme. the pea seed an ... | 1968 | 4387009 |
| the stoicheiometry of electron transfer by bacterial and plant ferredoxins. | 1. the number of electrons carried by ferredoxins from spinach, the blue-green alga anacystis nidulans, the anaerobic bacterium clostridium welchii and the photosynthetic bacterium chromatium was determined. 2. ferredoxins were reduced by illuminated chloroplasts, and the stoicheiometry of the reoxidation in the dark of the ferredoxins by nadp and benzyl viologen was measured. 3. spinach and a. nidulans ferredoxins were found to be one-electron carriers, and cl. welchii and chromatium ferredoxin ... | 1968 | 4387387 |
| [effect of antibodies against ferredoxin-nadp-reductase from spinach on photosynthetic reactions in a cell-free system of anacystis nidulans]. | | 1970 | 4393161 |
| purification and properties of a nicotinamide adenine dinucleotide phosphate-requiring glyceraldehyde 3-phosphate dehydrogenase from spinach leaves. | | 1970 | 4396069 |
| preliminary analysis of lipids and fatty acids of green bacteria and chloroflexus aurantiacus. | the complex lipids and fatty acids of the seven type species of green bacteria and three strains of chloroflexus aurantiacus were analyzed. the green bacteria contained lipids that behaved as cardiolipin and phosphatidylglycerol on thin-layer chromatography. they did not contain phosphatidylethanolamine or phosphatidylserine. similarly, chloroflexus contained lipids that behaved as phosphatidylglycerol and phosphatidylinositol on thin-layer chromatography and did not contain phosphatidylethanola ... | 1974 | 4421249 |
| degradation of monogalactosyl diglyceride and digalactosyl diglyceride by sheep pancreatic enzymes. | 1. saline extract of sheep pancreas acetone-dried powder was shown to catalyse acyl ester hydrolysis of spinach leaf galactosyl diglycerides and also galactosylglucosyl diglyceride of lactobacillus casei. 2. sodium deoxycholate stimulated the enzyme activity. ca(2+) had no effect on the hydrolysis of monogalactosyl diglyceride, but it enhanced that of digalactosyl diglyceride. when added together, there was considerably less activity with both the substrates. 3. optimal hydrolysis was observed a ... | 1974 | 4462578 |
| the role of molybdenum in the synthesis of nitrate reductase in cauliflower (brassica oleracea l. var botrytis l.) and spinach (spinacea oleracea l.). | | 1974 | 4474017 |
| nature of oxygen inhibition of nitrogenase from azotobacter vinelandii. | the reduction of nitrogen, acetylene, azide, and cyanide at various oxygen concentrations by nitrogenase from azotobacter vinelandii was measured with a well-defined system. oxygen inhibited the reduction of each substrate uncompetitively. the inhibition constants (k(i)) were 0.014, 0.023, 0.008, and 0.003 atm of oxygen for reduction of nitrogen, acetylene, azide, and cyanide, respectively. the system used included atp-generating components, subcellular particles from a. vinelandii with high nit ... | 1972 | 4501581 |
| biosynthesis of phosphatidylglycerol by cell-free preparations from spinach leaves. | | 1972 | 4554951 |
| fat metabolism in higher plants. liv. a procaryotic type acetyl coa carboxylase in spinach chloroplasts. | | 1972 | 4561257 |
| adenosine diphosphate sulphurylase activity in leaf tissue. | 1. a new method is described for the assay of adp sulphurylase. the method involves sulphate-dependent [(32)p]p(i)-adp exchange; the method is simpler, more sensitive and more direct than the method involving adenosine 5'-sulphatophosphate-dependent uptake of p(i). 2. adp sulphurylase activity was demonstrated in crude extracts of leaf tissue from a range of plants. crude spinach extract catalysed the sulphate-dependent synthesis of [(32)p]adp from [(32)p]p(i); spinach extracts did not catalyse ... | 1973 | 4582047 |
| siroheme: a new prosthetic group participating in six-electron reduction reactions catalyzed by both sulfite and nitrite reductases. | ferredoxin-nitrite reductase (ec 1.7.7.1) of spinach, an enzyme that catalyzes the six-electron reduction of nitrite to ammonia, contains siroheme, the new type of prosthetic group recently found in several sulfite reductases (both assimilatory and dissimilatory) that can catalyze the reduction of sulfite to sulfide, also a six-electron reduction. the prosthetic group of sulfite reductase had previously been shown to be an iron-tetrahydroporphyrin of the isobacteriochlorin type (adjacent pyrrole ... | 1974 | 4595566 |
| intracellular location of nitrate reductase and nitrite reductase. i. spinach and tobacco leaves. | | 1972 | 4649359 |
| aging of the photosynthetic apparatus. iv. similarity between the effects of aging and unsaturated fatty acids on isolated spinach chloroplasts as expressed by volume changes. | | 1972 | 4672617 |
| localization of enzymes within microbodies. | microbodies from rat liver and a variety of plant tissues were osmotically shocked and subsequently centrifuged at 40,000 g for 30 min to yield supernatant and pellet fractions. from rat liver microbodies, all of the uricase activity but little glycolate oxidase or catalase activity were recovered in the pellet, which probably contained the crystalline cores as many other reports had shown. all the measured enzymes in spinach leaf microbodies were solubilized. with microbodies from potato tuber, ... | 1973 | 4729505 |
| light-induced spectral changes of p700 in the 800-nm region in anacystis and spinach lamellae. | | 1973 | 4741140 |
| x-ray inactivation studies of nonheme iron proteins. the action of x-rays on spinach ferredoxin in aqueous solutions. | | 1973 | 4771323 |
| fat metabolism in higher plants. xxxv. partial primary structure of spinach acyl carrier protein. | | 1968 | 4877955 |
| [nitrite formation in vegetables and vegetable products. 2. baby food prepared from spinach]. | | 1971 | 4950684 |
| studies on fraction i protein. ii. comparison of physical, chemical, immunological and enzymatic properties between spinach and tobacco fraction i proteins. | | 1971 | 4995313 |
| a new photosynthetic pigment, "p430": its possible role as the priary electron acceptor of photosystem i. | the technique of flash kinetic spectrophotometry was used to demonstrate a broad absorption band around 430 nm, which was kinetically different from p700, in several photosystem-i particles from spinach and blue-green algae. the component represented by this absorption band, designated as "p430", was bleached as fast as p700. its recovery in the dark was accelerated by ferredoxin and by various artificial electron acceptors with redox potentials as low as -521 mv. the recovery kinetics have been ... | 1971 | 4995817 |
| multiple forms of -1,4 glucan synthetase from spinach leaves. | | 1971 | 4998187 |
| [formation and determination of nitric oxide in sterile, canned spinach]. | | 1971 | 5004938 |
| rapid detection and quantitative estimation of type a botulinum toxin by electroimmunodiffusion. | an experimental system is described for the detection and quantitative estimation of type a botulinum toxin by electroimmunodiffusion. the method is shown to be rapid, specific, and quantitative. as little as 14 mouse ld(50) per 0.1 ml of type a toxin was detected within 2 hr. when applied to experimentally contaminated foods such as canned tuna, pumpkin, spinach, green beans, and sausage, the technique detected botulinum toxin rapidly and identified it as to type and quantity. a specific rabbit ... | 1971 | 5005291 |
| effect of spinach and wakame on cholesterol turnover in the rat. | | 1972 | 5013280 |
| soluble adenosine diphosphate glucose- -1,4-glucan -4-glucosyltransferases from spinach leaves. | multiple forms of adp-glucose-alpha-1,4-glucan alpha-4-glucosyltransferase were obtained from spinach leaves by gradient elution from a deae-cellulose column. in the presence of high concentrations of some salts and bovine serum albumin, unprimed activity was found in one (transglucosylase iii) of the four fractions eluted from the column. in addition to having unprimed activity, transglucosylase iii had a lower k(m) for adp-glucose, a much higher k(m) for oyster glycogen, greater heat sensitivi ... | 1972 | 5073245 |
| properties of phosphoribulokinase from thiobacillus neapolitanus. | partially purified preparations of ribulose-5-phosphate kinase (specific activity, 50 to 125 mumoles per min per mg of protein) were employed in a series of kinetic experiments in the presence of several concentrations of h(+), mg(2+), adenosine triphosphate (atp), and phosphoenolpyruvate (pep). the ph optimum of the enzyme was found to be 7.9; at this ph and above, response of the enzyme to variations in atp concentration was hyperbolic, exhibiting a k(m) of 7 x 10(-4)m atp. at ph values below ... | 1972 | 5079073 |
| microwave hall mobility measurements on rat liver mitochondria and spinach chloroplasts. | | 1971 | 5137338 |
| the electron transport system in nitrogen fixation by azotobacter. i. azotoflavin as an electron carrier. | a flavoprotein, named azotoflavin, was isolated from an extract of azotobacter vinelandii cells, which linked the reducing power generated by illuminated spinach chloroplasts to the azotobacter nitrogen-fixing enzyme complex. the photoreduction of the yellow azotoflavin by chloroplasts produced a stable, free-radical semiquinone, blue in color, with properties similar to those described by other investigators for an azotobacter flavoprotein of unknown biological function. | 1969 | 5264138 |
| photoinactivation of aldolases by pyridoxal phosphate and its analogues. | pyridoxal phosphate can act as a specific photosensitizer for amino acid residues in rabbit muscle and spinach leaf aldolases, but the residues affected depend on the ph of the reaction. below ph 8 one histidine residue per enzyme subunit is destroyed; above ph 8.5 there is little loss of histidine, and photoinactivation is associated with the destruction of specific tyrosine residues, particularly the cooh-terminal residues. pyridoxal and 4-pyridinecarboxaldehyde are much less effective than py ... | 1971 | 5277095 |
| studies on spinach aldolase. | | 1969 | 5293629 |
| enzymatic synthesis of cystathionine by extracts of spinach, requiring o-acetylhomoserine or o-succinylhomoserine. | | 1966 | 5339715 |
| glyceraldehyde-3-phosphate dehydrogenase variants in phyletically diverse organisms. | electrophoretically distinct forms of glyceraldehyde-3-phosphate dehydrogenase (tdh) have been detected in turtle, perch, trout, spinach, and yeast. multiple forms were not detected in rat, rabbit, chicken, frog, honey bee, euglena, or escherichia coli. the combination of two different subunits into tetramers is a probable explanation for the five-membered sets usually detected in extracts exhibiting tdh multiplicity. | 1967 | 5341534 |
| structure and function of chloroplast proteins. ix. further comparative studies on chlorella and spinach leaf ribulose-1,5-diphosphate carboxylase. | | 1969 | 5391472 |
| photosensitization of specific histidine residues of rabbit muscle and spinach leaf aldolases by pyridoxal phosphate. | | 1970 | 5466118 |
| purification and some properties of a non-haem iron protein from the bacteroids of soya-bean (glycine max merr) nodules. | a non-haem iron protein was isolated from an extract of soya-bean nodule bacteroids by a procedure including protamine sulphate and heat precipitation followed by chromatography on deae-cellulose. the purified protein contains non-haem iron and acid-labile sulphur and exhibits a spectrum with a rather broad absorption shoulder in the region 380-440nm and a more prominent peak at 280nm. from sedimentation-velocity measurements an apparent s(20,w) value of 1.3s was calculated. the protein function ... | 1970 | 5529239 |
| effects of optically active 1-(alpha-methylbenzyl)-3-(3,4-dichlorophenyl)urea on reactions of mitochondria and chloroplasts. | effects of the r- and s-isomers and racemate of 1-(alpha-methylbenzyl)-3-(3,4-dichlorophenyl)urea (mbpu) were measured on phosphorylation and electron transport in mung bean (phaseolus aureus l.) mitochondria and spinach (spinacia oleracea l.) chloroplasts.in chloroplasts, s-mbpu inhibited basal and methylamine-uncoupled electron transport with ferricyanide as the oxidant, both photoreduction and coupled photophosphorylation with water as the electron donor and with ferricyanide and nicotinamide ... | 1971 | 5543784 |
| mechanism of inhibition of spinach beta-cystathionase by rhizobitoxine. | | 1971 | 5569130 |
| ferrochelatase of spinach chloroplasts. | spinach chloroplasts catalyse the incorporation of fe(2+) into protoporphyrin, mesoporphyrin and deuteroporphyrin to form the corresponding haems. this ferrochelatase activity was detected by pyridine haemochrome formation with acetone-dried powders of chloroplasts, or from the formation of [(59)fe]haems by intact chloroplasts. decreasing the mitochondrial contamination of the chloroplasts by density-gradient centrifugation did not cause any loss of activity: spinach ferrochelatase appears to be ... | 1968 | 5642615 |
| buoyant density of tobacco and spinach chloroplast dna. | | 1968 | 5649909 |
| spinach ferredoxin. ii. typtic, chymotryptic, and thermolytic peptides, and complete amino acid sequence. | | 1968 | 5651327 |
| an improved preparative method for spinach catalase and evaluation of some of its properties. | | 1968 | 5657866 |
| release of free fatty acids and loss of hill activity by aging spinach chloroplasts. | the free fatty acid content of spinach chloroplasts, isolated at ph 5.8 to 8.0, has been found to vary between 3.1 and 5.5% of the total chloroplast fatty acids. when chloroplasts were incubated at room temperature for 2 hours, the free fatty acids increased by 42% and the hill activity decreased by 70%. after 2 hours of incubation at 37 degrees , the free fatty acids increased about 3-fold and the hill activity decreased to almost 0. the addition of crystalline bovine serum albumin largely prev ... | 1968 | 5661491 |
| a survey of plants for leaf peroxisomes. | leaves of 10 plant species, 7 with photorespiration (spinach, sunflower, tobacco, pea, wheat, bean, and swiss chard) and 3 without photorespiration (corn, sugarcane, and pigweed), were surveyed for peroxisomes. the distribution pattern for glycolate oxidase, glyoxylate reductase, catalase, and part of the malate dehydrogenase indicated that these enzymes exist together in this organelle. the peroxisomes were isolated at the interface between layers of 1.8 to 2.3 m sucrose by isopycnic nonlinear ... | 1969 | 5775848 |
| measurement of the fluorescence lifetime of chlorophyll a in vivo. | new measurements have been made of fluorescence lifetime (tau) of chlorophyll a in the algae chlorella pyrenoidosa, porphyridium cruentum, anacystis nidulans, and in spinach chloroplast. tau-values of 0.6 and 0.7 nsec were obtained with green plants. anacystis and porphyridium gave a tau of 0.5 nsec. the previously described two stage decay of fluorescence in vivo in these organisms could not be confirmed. this observation could have been caused by a second wave of light emission from the exciti ... | 1969 | 5778187 |