text
stringlengths
35
50.6k
A systematic evaluation disclosed the following conditions to be optimum for the isolation of viable protoplasts from cultured cells of Nicotiana tabacum L. ;Bright Yellow' grown in liquid suspensions: (a) the cell culture in the early phase of cell number increase, (b) an enzyme mixture of 1% cellulase "Onozuka" and 0...
Protein bodies and spherosomes have been isolated from mature seeds of Sorghum bicolor (Linn.) Moench by a procedure which successfully disrupts the protein starch complex in the grain. Protein bodies from whole grain are 68% protein and have a distinct border and a monolithic appearance. Those from embryo are 95% prot...
The development of glycolate pathway enzymes has been determined in relation to photosynthetic competence during the regreening of Euglena cultures. Phosphoglycolate phosphatase and glycolate dehydrogenase rapidly reached maximal levels of activity but the complete development of ribulose 1,5-diphosphate carboxylase an...
Glucose 6-phosphate, fructose 6-phosphate, fructose 1, 6-diphosphate, and triose phosphates, and the enzymes phosphofructokinase, aldolase, and glucose 6-phosphate dehydrogenase were extracted from banana fruit (Musa cavendishii, Lambert var. Valery) at the (a) preclimacteric, (b) climacteric rise, (c) climacteric peak...
Chloroplasts contain the enzyme glutamine synthetase. Formation of glutamine by isolated chloroplasts is light-dependent and requires an intact outer envelope. Addition of exogenous glutamic acid, as well as nitrogen donors such as nitrite or ammonium, stimulate the synthesis of this amide. Photosynthetic generation of...
The walls of barley (Hordeum vulgare var. Himalaya) aleurone cells are composed of two major polysaccharides, arabinoxylan (85%) and cellulose (8%). The cell wall preparations contain 6% protein, but this protein does not contain detectable amounts of hydroxyproline. The arabinoxylan has a linear 1,4-xylan backbone; 33...
Data are presented which demonstrate a citrate cleavage enzyme in the supernatant of a developing soybean (Glycine max L. Merr., var. Harosoy 63) cotyledon homogenate following a 126,000g spin for 2 hours. Activity of the enzyme was observed directly in the supernatant enzyme preparation and in a desalted supernatant p...
Protein bodies and spherosomes isolated from mature seeds of Sorghum bicolor (Linn.) Moench have measurable activity of acid protease, alpha-glucosidase, beta-glucosidase, beta-galactosidase, phytase, acid pyrophosphatase, p-nitrophenyl phosphatase, and RNase. Protein bodies have largely insoluble activities, and produ...
ATPase activity of plasma membrane vesicles isolated from oat (Avena sativa L. cv. Goodfield) roots was examined in the presence of various concentrations of MgCl(2) and ATP. A Mg(2+): ATP ratio of about 1 was required for maximal activity regardless of the concentrations used; the optimum concentration for both Mg(2+)...
Enzyme preparations were obtained from cell wall debris of tomato (Lycopersicon esculentum L. cv. Tropic) fruits at various stages of ripeness and were assayed for glycosidase and polysaccharidase activities. In addition to polygalacturonase (mol wt 40,000), ripening fruits contain beta-galactosidase (mol wt 63,000) an...
The large, partly microsomal aggregate containing 4-hydroxycinnamate hydroxylase activity isolated from green leaves of Sorghum bicolor at pH 6 was obtained instead as intermediate molecular weight forms when green leaves were ground in the presence of 10 mm mercaptoethanol or dithiothreitol. Elution profiles from agar...
Soluble and mitochondrial malic dehydrogenases (MDH) were isolated from root tips of the halophyte Tamarix tetragyna L. grown in the presence and absence of NaCl. The activity of the enzymes isolated from root tips grown in the presence of NaCl was lower than that of the enzymes isolated from roots grown in absence of ...
Pea (Pisum sativum) leaf chloroplastic and cytoplasmic 3-phosphoglycerate kinases (ATP: d-3-phosphoglycerate 1-phosphotransferase, EC 2.7.2.3) have similar Michaelis constants for ATP, 0.7 and 0.55 mm, for ADP, 0.18 and 0.22, and for 3-P-glycerate, 0.59 and 0.54 mm at low substrate concentrations, and 1.6 and 1.25 mm a...
The induction of nitrate reductase activity in root tips of cotton (Gossypium hirsutum L.) was regulated by several amino acids and by ammonium. Glycine, glutamine, and asparagine strongly inhibited induction of activity by nitrate and also decreased growth of sterile-cultured roots on a nitrate medium. Methionine, ser...
When intact pea (Pisum sativum L.) plants are illuminated, the glycolytic enzyme phosphofructokinase is inactivated. In crude extracts the enzyme is inhibited by dithiothreitol. It would seem that this cytoplasmic enzyme, like glucose-6-P dehydrogenase, is light-inactivated when the enzymes of photosynthetic carbon met...
Cytochromes a + a(3), b, and c of mitochondria prepared from fertile and cytoplasmic male-sterile single- and double-cross maize (Zea mays L.) lines were examined by difference spectra at 25 C. The sterile lines contained the full complement of cytochromes, and absorption maxima were identical for each fertile-sterile ...
A substantial portion of the ribulose 1,5-diphosphate carboxylase activity in the endosperm of germinating castor beans (Ricinus communis var. Hale) is recovered in the proplastid fraction. The partially purified enzyme shows homology with the enzyme from spinach (Spinacia oleracea) leaves, as evidenced by its reaction...
The ontogeny of glyoxysomes and leaf peroxisomes has been examined in the cotyledons of germinating watermelon (Citrullus vulgaris) seedlings. Organelles from the cotyledons were extracted by razor blade homogenization and microbodies were separated by sucrose density gradient fractionation. Both kinds of microbodies h...
Glycolate oxidase is loosely held by microbodies obtained from etiolated barley (Hordeum vulgare L.) leaves depleted of nitrate. Defined centrifugation conditions cause the complete detachment of the enzyme from the microbodies. Addition of nitrate to these plants brings about a greater retention of glycolate oxidase b...
Sterile embryos of barley (Hordeum vulgare) and cultures of Lemna perpusilla have been labeled with (32)Pi and the chromatin proteins prepared and separated by acid-urea and sodium dodecyl sulfate gel electrophoresis. Under these conditions chromatin proteins became labeled and the gel radioactivity profiles which were...
This paper represents attempts to observe alterations in the pattern of chromatin protein phosphorylation in Lemna and barley (Hordeum vulgare).As judged by in vitro labeling the phosphorylation profile is substantially altered during germination. This may not be the result of specific tissue differentiation, however, ...
Electrophoretic examination of 22-day-old, normal maize (Zea mays L.) endosperm extracts revealed two zones of adenosine diphosphate glucose pyrophosphorylase activity. The enzymes are identical in terms of Km for glucose 1-phosphate and the effect of 3-phosphoglyceric acid on apparent Km for glucose 1-phosphate. Both ...
The leaf blade of cotton (Gossypium hirsutum L. cv. Stoneville 213) was investigated as the initial site of ethylene action in abscission. Ethylene applied at 14 mul/l to intact 3-week-old plants caused abscission of the third true leaf within 3 days. However, keeping only the leaf blade of this leaf in air during ethy...
The conditions and requirements for an in vitro protein synthesizing system from the moss Tortula ruralis are outlined. Using this system the effects of desiccation, achieved quickly or slowly, were studied. Slowly dried moss retained fewer polyribosomes on desiccation but more active ribosomes than rapidly dried moss....
Ribulose 1,5-diphosphate carboxylase has been purified from extracts of autotrophically grown Chlorella fusca by ammonium sulfate precipitation and centrifugation on a linear sucrose density gradient. The enzyme was homogeneous by the criterion of polyacrylamide gel electrophoresis. The molecular weight of the enzyme w...
The activity and subcellular distribution of acid phosphatase were assayed during ethylene-induced ripening of whole fruit or thick slices of avocado (Persea americana Mill. var. Fuerte and Hass). The activity increased up to 30-fold during ripening in both the supernatant fraction and the Triton X-100 extract of the p...
Apparent Km and V(max) values were obtained for hydrolysis of methyl and ethyl chlorophyllides a, methyl and ethyl pheophorbide a, and 9-hydroxymethyl pheophorbide a by chlorophyllase from Ailanthus altissima. Analysis of substrate specificity data for chlorophyllase indicates that the presence of a 9-keto group and a ...
An 8-fold enhancement in the activity of a DNA-dependent DNA polymerase was found in extracts from germinating wheat (Triticum vulgare var. Florence) embryos, as compared to the activity found in extracts from ungerminated embryos. The enhancement of this activity during the first hours of germination is concomitant to...
ORNITHINE: 2-oxoacid aminotransferase (EC 2.6.1.13) has been purified over 400-fold with a total recovery of 14% from acetone powders of cotyledons of germinating squash (Cucurbita pepo, L.) seedlings. The pH optimum of the transamination between l-ornithine and alpha-ketoglutarate is 8 and the Michaelis constants are ...
Glandless cotton plants (Gossypium hirsutum L. cv. Coker 100) were subjected to the influence of high CO(2)-bicarbonate. The content of protein decreased with no accompanying increase in its degraded products. The decrease in protein was correlated with the low content of chlorophyll and also with the reduced activity ...
Pulse labeling of carrot root phloem parenchyma (Daucus carota L. cv. Nantes) tissue with (14)C-proline followed by fractionation of the cytoplasmic organelles on sucrose gradients was used to determine the identity of the membranous organelles involved in the secretion of the hydroxyproline-rich glycoproteins of the c...
Various enzymes of glycerol metabolism in the extracts of 5-day-old eastor bean (Ricinus communis L. var. Hale) endosperm and 4-day-old peanut (Archis hypogaea L.) cotyledon were studied. NAD-glycerol dehydrogenase and NAD-alpha-glycerolphosphate dehydrogenase were not detected. Glycerol kinase was detected in the solu...
The content of specific enzymes in microbodies isolated from tobacco Nicotiana rustica, L. leaves may vary according to the procedure followed during the isolation of the organelles. The type of homogenizing medium, its ionic components and the ratio of medium to tissue during homogenization, affect the over-all yield ...
A new enzyme, named uronic acid oxidase, was extracted and purified 67-fold by (NH(4))(2)SO(4) fractionation and CM-Sephadex column chromatography from ethylene-treated Shamouti orange (Citrus sinensis L. Osbeck) leaves. The enzyme catalyzes the oxidation of d-galacturonic acid and d-glucuronic acid to the correspondin...
Leaves and pith of Turkish, Wisconsin 38, and Samsun NN tobacco (Nicotiana tabacum) varieties, which differ in their sensitivity to tobacco mosaic virus, showed the same qualitative isoperoxidase patterns and a similar distribution of distinctive isoperoxidases between the cell protoplast and wall-free, ionically, and ...
The ultrastructure of mesophyll chloroplasts of maize (Zea mays L.) was more severely affected by iron deficiency that induced mild chlorosis than was the ultrastructure of bundle sheath plastids. Ferredoxin and ribulose diphosphate carboxylase levels were severely decreased by iron deficiency. Malic enzyme was less af...
Bicarbonate-(14)C was provided to 5- and 11-day-old suspension cultures of Paul's Scarlet rose, and the incorporation of (14)C into lipid, protein, amino acids, and organic acids was determined. The rate of bicarbonate uptake was approximately the same by 5- and 11-day-old cells, but the distribution of (14)C among cel...
Concanavalin A, the lectin of the Jack bean, Canavalia ensiformis, was extracted and compared with homologous proteins from Canavalia gladiata and Canavalia maritima. All proteins were bound to Sephadex G-100 and eluted from the gel with buffered glucose solution. Quantitative recoveries indicated that large quantities...
Glucose 6-phosphate dehydrogenase (EC 1.1.1.49) has been partially purified from Anacystis nidulans and Anabaena flos-aquae by means of ammonium sulfate fractionation and exclusion gel chromatography and the kinetic properties determined.Glucose 6-phosphate dehydrogenase from these blue-green algae exhibits Michaelis-M...
The effects of a series of concentrations of ethylene (10, 20, 40, to 10,240 nl/l) on elongation, diameter, and geotropism of the stems and roots of etiolated seedlings of Pisum sativum L., Arachis hypogea L., Phaseolus vulgaris L., and Gossypium hirsutum L. were measured or observed. Of the 24 possible responses, 4 we...
Recent publications have indicated that a KCl-stimulated ATPase from cereal roots is specifically associated with plasmalemma-enriched membrane fractions. However, in previous work we found that relatively high specific activities of this enzyme were also associated with a membrane fraction which did not contain plasma...
Ribulose 1,5-diphosphate carboxylase (RuDPCase, EC 4.1.1.39) isolated from spinach leaves is metabolically regulated at 10 mm Mg(2+) and low CO(2) concentrations by its substrates (RuDP and CO(2)) and by effectors which include 6-phosphogluconate (6-PGluA), NADPH, and fructose 1,6-diphosphate (FDP), but not fructose 6-...
The effect of carbohydrate on arginine utilization by excised bean (Phaseolus vulgaris L. var. Tendergreen) leaves in the dark was studied by adding arginine to leaves differing in carbohydrate levels, and measuring the arginine content of the leaves at intervals. In nonstarved leaves, the arginine content decreased st...
A comparative study of peptide composition and freeze-fracture morphology of chloroplast membranes from a chlorophyll b-less mutant and a normal barley plant (Hordeum vulgare L.) is reported in this work. Using a high resolution, discontinuous sodium dodecyl sulfate-acrylamide gel electrophoretic system, we show that t...
Water stress causes both a qualitative change in the types of proteins produced by Avena coleoptile cells as demonstrated by a double-labeling ratio technique, and a quantitative reduction in the rate of incorporation of leucine into proteins. The osmotica mannitol and Carbowax-4000 cause similar changes in the pattern...
The standard procedure for the in ritro extraction of nitrate reductase from the tip region (0-2 cm) of the primary root of the maize (Zea mays L.) seedling indicated an activity of the enzyme approximately 5-fold higher than that obtained with an in vivo assay. In more mature regions of the primary root the ratio of i...
Water stress causes a reduction in hydrostatic pressure and can cause an increase in abscisic acid in plant tissues. To assess the possible role of abscisic acid and hydrostatic pressure in water stress effects, we have compared the effects of water stress, abscisic acid, and an imposed hydrostatic pressure on the rate...
A marked loss of leucine (14)C incorporation occurred in chloroplasts isolated from Nicotiana rustica L. leaves exposed to 24 hours of darkness. This loss is not due to an initial decline in RNA-synthesis potential of the chloroplasts, as was inferred from the extent of UTP incorporation by the isolated chloroplasts. U...
Possible involvement of protein synthesis in the germination of Onoclea sensibilis spores was investigated by temporarily applying 0.1 mm cycloheximide before and after photoinduction. Cycloheximide was shown to inhibit protein synthesis, but not to act as an uncoupler of respiration. When cycloheximide was added befor...
A peptidase acting on Leu-Gly-Gly and Leu-Tyr at pH 8 to 10 was purified about 670-fold from germinated grains of barley (Hordeum vulgare L.). Gel electrophoretic analyses indicated a purity of about 90%. The purified enzyme is remarkably similar to mammalian leucine aminopeptidases (EC 3.4.1.1) both in chemical and in...
Cycloheximide is frequently presumed to inhibit specifically the cytoplasmic protein synthesis of eukaryotes. Although previous investigators have shown that it had other effects on the cells of a variety of organisms, these results were frequently presumed to be secondary effects of the inhibition of protein synthesis...
After a preirradiation with ultraviolet light, phenylalanine ammonia-lyase activity in cell suspension cultures of parsley (Petroselinum hortense Hoff.) is controlled by phytochrome (red/far red photoreversibility). Isopycnic CsCl density gradient centrifugation, after labeling with (15)N (90 atom%) under inductive and...
The changes in chlorophyll and protein in senescing chloroplasts isolated from the first leaves of 7-day-old oat (Avena sativa) seedlings have been investigated. In darkness the chlorophyll in these plastids is highly stable, losing only 5 to 10% of its content after 7 days at 26 C. This result contrasts with the behav...
Mesophyll cells, protoplasts, and protoplast extracts of Digitaria sanguinalis were used for comparative studies of light-dependent CO(2) fixation. CO(2) fixation was low without the addition of organic substrates. Pyruvate, oxaloacetate, and 3-phosphoglycerate induced relatively low rates (10 to 90 mumoles/mg chloroph...
From measurements of viability after exposure of tubers to natural overwintering in the soil and 6 weeks exposure at 2 C, species cold tolerance of the tubers was ranked in decreasing order: yellow nutsedge ;I' (Cyperus esculentus L.), an ecotype originating in Illinois; yellow nutsedge ;G', an ecotype originating in G...
Long chain dicarboxylic acids are constituents of the protective biopolymers cutin and suberin of plants. Cell-free extracts from the excised epidermis of Vicia faba leaves catalyzed conversion of 16-hydroxy[G-(3)H]hexadecanoic acid to the corresponding dicarboxylic acid with nicotinamide-adenine dinucleotide phosphate...
The transfer of dark-grown cultures of Euglena gracilis Klebs strain Z regreening in the light back into darkness resulted in a dramatic increase in ribulose diphosphate carboxylase activity. On a culture volume basis activity increased 4-fold over a 24-hour dark period, although on a protein basis activity declined be...
The development of amylase activity in extracts from de-embryonated and GA(3)-treated de-embryonated maize kernels (Zea mays L.) was determined during a 10-day incubation period. The increase in activity was compared with activity extracted from endosperms dissected from germinating whole kernels. Chromatographic analy...
Energy dispersive x-ray analysis was used to study the composition of certain protein body components in Cucurbita maxima cotyledons. The globoid crystal was rich in phosphorus, potassium, and magnesium. This elemental composition provides further evidence that the globoid crystal in squash cotyledon protein bodies is ...
Symptoms typical of senescence occurred in green detached primary barley (Hordeum vulgare L.) leaves placed in darkness and in light. Chlorophyll, total soluble protein, ribulose 1,5-diphosphate carboxylase protein and activity each progressively decreased in darkness and to a lesser extent in light. In all treatments ...
The regulation of CO(2) assimilation by intact spinach (Spinacia oleracea) chloroplasts by exogenous NADP-linked nonreversible d-glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.9) was investigated. This dehydrogenase mediated a glyceraldehyde 3-phosphate/glycerate 3-phosphate shuttle for the indirect transfer of NAD...
The autodigestive proteolytic activity of extracts of cotyledons of mung beans (Phaseolus aureus Roxb.) increased 4- to 5-fold during germination. A similar increase was found in the ability of these extracts to digest added casein or mung bean globulins. The increase occurred after a 2-day lag during the next 2 to 3 d...
Auxin-induced ethylene formation in etiolated pea (Pisum sativum L. var. Alaska) stem segments was inhibited by inhibitors of RNA and protein synthesis. Kinetics of the inhibitions is described for actinomycin D, cordycepin, alpha-amanitin, and cycloheximide. alpha-Amanitin was the most potent and fast-acting inhibitor...
Rehydration of Tortula ruralis in 2,4-dinitrophenol inhibits protein synthesis, polysome formation, and ATP production. Polysomes are conserved intact and are active in vitro in hydrated Tortula placed in this chemical, although in vivo protein synthesis is inhibited. Hydrated moss placed under nitrogen in the dark sho...
The enzymic formation of acetylglutamate has been studied in Chlorella vulgaris extracts. Acetyl CoA and N(2)-acetyl-l-ornithine served as substrates for glutamate acetylation whereas acetylphosphate, N(5)-acetyl-l-ornithine, and N(2)-acetyl-2,4-diamino butyrate were ineffective. Acetyl CoA-glutamate transacetylase and...
The role of phytochrome in the induction of nitrate reductase of etiolated field peas (Pisum arvense L.) was examined. Terminal bud nitrate concentration increased in darkness, and the increase correlated with induction of nitrate reductase following brief exposure of intact plants to red, blue, far red, and white ligh...
An enzyme was extensively purified from jack bean leaves (Canavalia ensiformis L.) which produced o-ureidohomoserine from l-canaline and carbamyl phosphate. The most highly purified preparations catalyzed both this reaction and citrulline synthesis from ornithine and carbamyl phosphate, and the ratio of the two activit...
The sensitivity of homoserine dehydrogenase (EC 1.1.1.3) to inhibition by the feed-back modifier, l-threonine, was examined in preparations derived from etiolated shoots, roots, and lightgrown tissues of Zea mays L. var. earliking. A progressive decrease in enzyme sensitivity was observed during seedling growth. Enzyme...
The host-specific toxin produced by Helminthosporium maydis, race T, causes 50% inhibition of dark fixation of (14)CO(2) by leaf discs of susceptible (Texas male sterile) corn when it is diluted to approximately 1/10,000 of the volume of the original fungus culture filtrate. Dilutions of 1/10 or less are required for e...
The relative contribution of each of several forms of homoserine dehydrogenase (EC 1.1.1.3) to the total enzyme population in etiolated shoots and in roots of Zea mays L. var. earliking was examined by the use of gel filtration chromatography and disc gel electrophoresis. In enzyme preparations derived from shoots of s...
During germination of castor bean seeds (Ricinus communis var. Hale), the changes of activity of catalase, uricase, and alpha-hydroxyacid oxidase of the endosperm follow a rise and fall pattern with a peak between day 4 and 5 similar to that observed for the glyoxylate cycle enzymes. After 3 days of germination, most o...
The time course of (36)Cl(-) uptake from 5 mm KCl by 1.5-mm leaf segments of Triticum aestivum L. seedlings has been determined over 24 hours both in the light and in the dark. A light-enhanced uptake of Cl(-) develops after a few hours. Using whole laminae which have been water-injected by vacuum infiltration, a light...
The oxidation of malate and citrate by isolated plant mitochondria can be stimulated by the addition of inorganic phosphate. This stimulation (a) is not inhibited by oligomycin or uncouplers; (b) can not be duplicated by addition of adenine nucleotide; (c) is inhibited by 2-n-butylmalonate; and (d) is not evident in de...
If cell wall hydrolytic enzymes are involved in extension growth, a correlation may be expected between hydrolytic activity of the cell walls and growth rate of the tissue from which the walls are prepared. Epicotyl sections from 0 to 5 mm, 6 to 10 mm, and 11 to 15 mm below the apical hook of pea seedlings (Pisum sativ...
Five-day-old seedlings of corn (Zealpha mays L.) grown without nitrate were decapitated and exposed to 0.5 mm KNO(3) or 0.5 mm KCl in aerated solutions at 30 C. Uptake of nitrate, chloride, and potassium was determined by replacing solutions hourly and measuring their depletion. Translocation of these ions and of organ...
Two major proteins (the 7S and 11S globulins) of soybean (Glycine max) were simultaneously isolated by a simple method based on their different solubilities in dilute tris (hydroxymethyl) aminomethane buffers. The purified 7S globulins, which represented essentially the entire 7S soybean protein fraction capable of dim...
Gas exchange and protein metabolism were studied in expanding, mature, and near-senescent leaves of young clonal Populus x euramericana cv. Wisconsin-5 plants. Dark respiration, CO(2) evolution in the light, and CO(2) compensation concentrations were highest in unexpanded leaves but declined markedly as leaves matured ...
beta-1, 4-Glucan (cellulose) synthetase activity (UDP-glucose: beta-1, 4-glucan-glucosyl transferase) present at cell surfaces of growing regions of Pisum sativum epicotyl was assayed by supplying UDP-(14)C-glucose directly to thin slices of tissue. Initial rates of glucosyl transfer under these conditions approached t...
Ribosomal subunits prepared by NH(4)Cl dissociation (0.5 m) of the monomeric ribosomes were much less active in in vitro protein synthesis than those prepared by KCl dissociation. The decrease in activity correlated with a detachment of some proteins (L(2) and L(9) as shown by gel electrophoresis) within the 60S riboso...
The pattern of change in the activity of alcohol dehydrogenase in maize (Zea mays L.) scutellum during seed germination is not altered by 10 mug/ml cycloheximide or 50 mug/ml actinomycin D. The enzyme does not become density labeled when maize seeds are germinated in the presence of D(2)O and (15)NH(4)Cl, indicating th...
Phosphoenolpyruvate (PEP) carboxykinase activity was found in crude extracts of ;Pinot noir' grape berries. The enzyme required ATP, Mn(2+) plus Mg(2+), a pH of 6.6, and a temperature of 40 C for maximum activity. The range in concentration of oxaloacetic acid needed for maximum phosphoenolpyruvate carboxykinase activi...
After 30 minutes of incubation of young leaf sections of d-5 maize (Zea mays L.) in [(3)H]gibberellin A(1) ([(3)H]GA(1)), the metabolite [(3)H]GA(8) was present in significant amounts, with a second metabolite, [(3)H]GA(8)-glucose ([(3)H]GA(8)-glu), appearing soon after. A third [(3)H]GA(1) metabolite, the polar unchar...
A quick procedure for the isolation of nuclei with good yield from soybean hypocotyl (Glycine max var. Wayne) was developed. The isolated nuclei appeared to retain their structural integrity. They were typically ellipsoidal with minima and maxima diameter of about 6 and 8 to 10 micrometers. While the nuclei were simila...
A particulate fraction from pollen tubes and ungerminated pollen of Lilium longiflorum incorporated (14)C-glucose from UDP-glucose-(14)C into a lipid fraction and into beta-1, 3-glucan. Partial hydrolysis of the glucan yielded laminaribiose as the only radioactive disaccharide. The preferred substrate was UDP-glucose, ...
The rate of chlorophyll formation in initially etiolated pea seedlings (Pisum sativum) that are growing in the light in salinized media is slower than in similar plants not subjected to salinity. However, the final steady state level of chlorophyll is the same under both conditions. Growth under saline conditions did n...
In the developing seed coat of Pisum elatius, o-dihydroxyphenols are present in appreciable amounts at all stages of development. However, catechol oxidase activity rises sharply during the later stages of development, shows a further abrupt rise during dehydration of the seed coat, and then decreases. It is suggested ...
The incorporation and distribution of photosynthetically fixed (14)CO(2) was followed for 48 hours in a recently matured source leaf (LPI 7) and in young expanding source and sink leaves (LPI 4) of cottonwood (Populus deltoides Bartr.). The major chemical constituents of leaf laminae and petioles were separated by sequ...
This study describes the isolation and characterization of p-fluorophenylalanine-resistant diploid tobacco (Nicotiana tabacum L.) and diploid carrot (Daucus carota L.) cultured cell lines. The p-fluorophenylalanine-resistant tobacco and carrot lines can grow in medium containing p-fluorophenylalanine concentrations 10 ...
The characteristics of the enzyme Delta(1)-pyrroline-5-carboxylic acid dehydrogenase from etiolated barley (Hordeum distichum) shoots have been examined. The bulk of the enzyme activity was found in the 10,000g pellet fraction, this activity being displayed only after detergent treatment of the suspended pellet. The en...
Storage protein hydrolysis in the cotyledons of germinating mung beans (Phaseolus aureus Roxb.) was examined by histochemical techniques, and the autolytic capacity of isolated protein bodies was studied with biochemical methods. The localization of endopeptidase activity within the cotyledons was studied using an Indi...
The secreted slime from root cap cells of corn (Zea mays, cv. SX-17) was studied. Production of slime by excised root tips is stimulated by the addition of 40 mM sucrose or fucose and half-strength Hoagland's solution to the incubation medium. Secreted slime was recovered from aqueous solution by precipitation with eth...
The degradation of the storage carbohydrate, paramylum, is induced by light in wild-type Euglena gracilis Klebs var. bacillaris Pringsheim and in a mutant, W(3)BUL, which lacks detectable plastid DNA. Treatment of wild type with cycloheximide in the dark produces 60% as much paramylum breakdown as light, whereas treatm...
The use of mesophyll protoplast extracts from various C(4) species has provided an effective method for studying light-and substrate-dependent formation of oxaloacetate, malate, and asparate at rates equivalent to whole leaf C(4) photosynthesis. Conditions regulating the formation of the C(4) acids were studied with pr...
Highly purified phytochrome samples from rye (Secale Cereale cv. Cougar) were fractionated by ultracentrifugation in isokinetic sucrose density gradients. Three protein species were separated with estimated sedimentation coefficients of 6.5S, 8.0S, and 11.5S. The 6.5S and 8.0S forms contained photoreversible phytochrom...
Ribulose 1,5-diphosphate carboxylase (RUDPcase) from autotrophically grown Euglena gracilis was purified to homogeneity as measured by analytical ultracentrifugation, polyacrylamide gel electrophoresis, and immunoprecipitation reactions. The enzyme represented about 9% of total protein and 24% of soluble protein in the...
Short term inhibitor treatment can be used to examine the processes that occur during an inductive dark period in the short day plant Lemna perpusilla Torr., strain 6746. Several inhibitors of protein biosynthesis are most effective in reducing per cent flowering when treatment occurs over the 2-hour intervals beginnin...
Phosphoenolpyruvate (PEP) carboxylase activity in immature ;Carignane' grape berries (Vitis vinifera L.) had a temperature optimum of about 38 C, whereas malic enzyme activity rose with increasing temperature between 10 and 46 C. In vitro temperature inactivation rates for the PEP carboxylase were markedly greater than...
The time of synthesis, the molecular weight, and the relative glutamine-glutamate and proline to leucine ratios of the endosperm proteins of wheat (Triticum aestivum L. cv. Logan) were determined using a sodium dodecyl sulfate-polyacrylamide gel technique. In general, synthesis of most proteins occurred through much of...
A technique is described for the isolation of structurally intact and partially active chloroplasts from photoheterotrophically grown Euglena gracilis. The separation of intact chloroplasts from stripped chloroplast membranes and other subcellular particles was achieved by sedimentation in continuous, isosmotic density...
Sugarcane clones susceptible to eye spot disease became resistant to the pathogen or helminthosporoside activity during warm summer months. Exposure of plants to 30 to 35 C temperatures, hot water treatment of excised leaves from 30 to 50 C, preincubation of leaves in an N(2) atmosphere, or preincubation in the presenc...