Xylem translocation of amino acids from roots to shoots in cottonwood plants

1979 ◽  
Vol 9 (3) ◽  
pp. 374-378 ◽  
Author(s):  
Richard E. Dickson
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Organic Acids ◽  
Xylem Sap ◽  
Aminobutyric Acid ◽  
Acid Fraction ◽  
Root Pressure ◽  
Xylem Exudate ◽  
And Storage ◽  
Total Amino Acids

Xylem sap produced by root pressure and collected from topped cottonwood (Populusdeltoides Bartr.) contained sugars, organic acids, amino acids, protein, and inorganic nutrients. Amino acids and NO3N were present at the highest concentrations. Total amino acids in xylem sap ranged from 3 to 10 mol m−3 and NO3N ranged from 7 to 10 mol m−3. When lower leaves were photosynthetically labeled with 14CO2, activity was rapidly translocated to roots and recycled to shoots. Within 6 h after labeling leaves, xylem exudate contained between 1 and 2 × 106 disintegrations min−1 cm−3. Most of the activity (50 to 70%) was in the amino acid fraction. Although nine amino acids contained some activity, more than 90% of the 14C was found in five common transport and storage amino acids: asparagine, glutamine, serine, alanine, and γ-aminobutyric acid. Glutamine contained 60 to 70% of the activity in the amino acid fraction 2 h after topping. Sugars, translocated from lower leaves to roots via the ploem, are converted to amino acids in roots and then translocated to the developing shoot via the xylem.

The Xylem Sap of Maize Roots: Its Collection, Composition and Formation

1988 ◽  
Vol 15 (4) ◽  
pp. 557 ◽  
Author(s):  
MJ Canny ◽  
ME Mccully
Keyword(s):  
Amino Acids ◽  
Organic Acids ◽  
Organic Acid ◽  
Aspartic Acid ◽  
Xylem Sap ◽  
Great Variability ◽  
Reduced Pressure ◽  
Transpiration Stream ◽  
Maize Roots ◽  
Total Amino Acids

Three methods of sampling xylem sap of maize roots were compared: sap bleeding from the stem cut just above the ground; sap bleeding from the cut tops of roots still undisturbed in the ground; and sap aspirated from excavated roots under reduced pressure. The bleeding saps were often unobtainable. When their composition was measured with time from cutting, the concentrations of the major solutes approximately doubled in 2 h. Aspirated sap was chosen as the most reliable sample of root xylem contents. Solute concentrations of the saps showed great variability between individual roots for all solutes, but on average the concentrations found (in �mol g-1 sap) were: total amino acids, 1.8; nitrate, 1.8; sugars (mainly sucrose), 5.4; total organic acids, 18.3. Individual amino acids also varied greatly between roots. Glutamine, aspartic acid and serine were generally most abundant. The principal organic acid found was malic, approximately 8 �mol g-1. From these analyses the ratios of carbon in the fractions (sugars : amino acids : organic acids) = (44 : 6 : 50). 14Carbon pulse fed to a leaf appeared in the root sap within 30 min, rose to a peak at 4-6 h, and declined slowly over a week. During all this time the neutral, cation and anion fractions were sensibly constant in the proportions 86 : 10 : 4. The 14C therefore did not move towards the equilibrium of 12C-compounds in the sap. It is argued that the results do not support a hypothesis of formation of amino carbon from recent assimilate and reduced nitrate in the roots and an export of this to the shoot in the transpiration stream.

Purification of Antihemophilic Factor (Factor VIII) by Amino Acid Precipitation*

1964 ◽  
Vol 11 (01) ◽  
pp. 064-074 ◽  
Author(s):  
Robert H Wagner ◽  
William D McLester ◽  
Marion Smith ◽  
K. M Brinkhous
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Factor Viii ◽  
Plasma Protein ◽  
Acid Precipitation ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Specific Procedure ◽  
Beta Alanine ◽  
Antihemophilic Factor

Summary1. The use of several amino acids, glycine, alpha-aminobutyric acid, alanine, beta-alanine, and gamma-aminobutyric acid, as plasma protein precipitants is described.2. A specific procedure is detailed for the preparation of canine antihemophilic factor (AHF, Factor VIII) in which glycine, beta-alanine, and gammaaminobutyric acid serve as the protein precipitants.3. Preliminary results are reported for the precipitation of bovine and human AHF with amino acids.

Root uptake and xylem transport of cadmium in wheat and triticale as affected by exogenous amino acids

2017 ◽  
Vol 68 (5) ◽  
pp. 415 ◽  
Author(s):  
K. Khodamoradi ◽  
A. H. Khoshgoftarmanesh ◽  
S. A. M. Mirmohammady Maibody
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Bread Wheat ◽  
Nutrient Solution ◽  
Metal Ion ◽  
Xylem Sap ◽  
Root Uptake ◽  
Plant Roots ◽  
Control Treatment ◽  
Long Distance

Organic acids exuded from plant roots significantly modify uptake and long-distance translocation of metals. Little is known about the effect of amino acids on metal ion uptake by plant roots. The present study investigated the effects of exogenous amino acids (histidine and glycine) in a nutrient solution on root uptake and xylem sap transport of cadmium (Cd) in triticale (× Triticosecale cv. Elinor) and bread wheat (Triticum aestivum L. cv. Back Cross Rushan). Plant seedlings were grown in a Cd-free modified Hoagland nutrient solution to which 1 µm Cd was added with either 50 µm histidine or 50 µm glycine or without amino acids at 4 weeks after germination. A control treatment consisted of a nutrient solution free of Cd and amino acids. In bread wheat, addition of histidine to the Cd-containing nutrient solution resulted in a higher operationally defined symplastic Cd fraction but a lower apoplastic one in the roots. In triticale, addition of either amino acid decreased the symplastic Cd fraction but increased the apoplastic one. Addition of histidine to the nutrient solution increased Cd concentration in wheat xylem sap but had no significant effect on Cd concentration in triticale xylem sap. Compared with the Cd-only treatment, the glycine-containing treatment led to significantly reduced Cd concentrations in xylem sap of both plant species. Wheat plants supplied with histidine and Cd accumulated greater amounts of Cd in their shoots than those supplied with Cd alone. Glycine had no significant effects on the Cd content of wheat shoots but decreased it in triticale shoots. Results indicate that the effects of amino acids on plant root uptake and xylem sap translocation of Cd depend on the type of amino acid supplemented. This finding is of great importance for selecting and/or breeding cultivars with Cd-toxicity tolerance.

scholarly journals Quantification By Gas Chromatography of the Content of Amino Acids Present in Sausages Fortified with Quinoa Vegetable Protein

2021 ◽  
Author(s):  
A. Zavala ◽  
M. González ◽  
P. Pino
Keyword(s):  
Amino Acids ◽  
Gas Chromatography ◽  
Amino Acid ◽  
Vegetable Protein ◽  
Amino Acid Profile ◽  
Aminobutyric Acid ◽  
Precolumn Derivatization ◽  
Proportional Relationship ◽  
Quinoa Flour

The objective of this research was to determine the quality of the protein present in sausages fortified with quinoa as a substitute for animal protein, through the identification and quantification of amino acids, using gas chromatography and precolumn derivatization. The amino acid composition found in the analyzed products was predominantly composed of: Threonine (THR) with a concentration of 1046.32µmol / L, aminobutyric acid (ABA) with a concentration of 9685.68 µmol / L and glutamic acid (GLU) with a concentration of 1178.71 µmol / L. These values were found in the treatment with the highest percentage of quinoa flour, establishing a directly proportional relationship between the concentrations of these amino acids and the percentage of quinoa. Gas chromatography was an adequate technique for determining the amino acid profile due to its speed and sensitivity. Keywords: amino acids, sausages, quinoa, derivatization, gas chromatography. RESUMEN La presente investigación tiene por objetivo determinar la calidad de la proteína presente en embutidos fortificados con quinua como sustituyente de la proteína animal, a través de la identificación y cuantificación de aminoácidos mediante la aplicación de cromatografía de gases y la derivatización precolumna. La composición de aminoácidos encontrada en los productos analizados destaca la presencia mayoritaria de: Treonina (THR) con una concentración de 1046,32 µmol/L, ácido aminobutírico (ABA) con una concentración de 9685,68 µmol/L  y ácido glutámico (GLU) con una concentración de 1178,71 µmol/L, todos estos valores se presentaron en el tratamiento con mayor porcentaje de harina de quinua estableciéndose una relación directamente proporcional entre las concentraciones de estos aminoácidos y el porcentaje de adición de quinua en los tratamientos estudiados. Se puede concluir que la cromatografía de gases empleada resultó una técnica adecuada para la determinación del perfil aminoacídico por la rapidez y sensibilidad presentada sobre las muestras estudiadas.  Palabras claves: aminoácidos, embutidos, quinua, derivatización, cromatografía de gases.  

Radiation Damage to Polypeptides and Proteins in the Solid State: Changes in Amino Acid Composition *

1981 ◽  
Vol 36 (3-4) ◽  
pp. 310-318 ◽  
Author(s):  
J. Seredynski ◽  
T. Söylemez ◽  
W. Baumeister
Keyword(s):  
Amino Acids ◽  
Electron Microscope ◽  
Amino Acid ◽  
Solid State ◽  
Trypsin Inhibitor ◽  
Concanavalin A ◽  
Thin Layers ◽  
Aminobutyric Acid ◽  
Sensitivity Pattern ◽  
State Changes

Thin layers of synthetic homopolypeptides (poly-α-Ala, -Arg, -Asn, -Asp, -Glu, -His, -Lys and -Tyr) and proteins (myoglobin, concanavalin A, trypsin-inhibitor) were irradiated under solid state conditions in an electron microscope with 100 keV electrons. Radiolytic changes were investigated by amino acid analysis. The results are discussed in terms of the relative radiosensitivities of the constituent amino acids, and possible topochemical effects on the sensitivity pattern emerging. An attempt is also made to trace at least some of the predominant pathways of amino acid transformation, namely the production of alanine and a-aminobutyric acid

Effect of Salinity on Photosynthetic 14CO2 Fixation and Amino Acid Pools of Bellerochea yucatanensis (v. Stosch) and Thalassiosira rotula (Meunier)

1985 ◽  
Vol 40 (7-8) ◽  
pp. 527-530
Author(s):  
Günter Döhler ◽  
Joachim Zink
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Aspartic Acid ◽  
Marine Diatoms ◽  
14Co2 Fixation ◽  
Low Salt ◽  
Photosynthetic Products ◽  
Sugar Phosphates ◽  
Total Amino Acids

Abstract The marine diatoms Bellerochea yucatanensis and Thalassiosira rotula were grown at different salinities (20/25, 35, and 40/45‰ salinity (S), respectively) under normal air (0.035 vol.% CO2). No significant variations in the percentage of gross photosynthetic products (e.g. total amino acids, sugar phosphates) were found as a function of salinity during growth. The bulk of the soluble 14C-radioactivity was detected in amino acids. 14C-labelling of glutamine increased markedly with salinity. Low salt - grown algae are characterized by enhanced amino acid pools, mainly of aspartic acid, asparagine and glutamine. It was found that the tested amino acids are not involved in osmoregulation.

Intracellular osmoregulatory role of amino acids and urea in marine elasmobranchs

1976 ◽  
Vol 230 (4) ◽  
pp. 925-931 ◽  
Author(s):  
RP Forster ◽  
L Goldstein
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Extracellular Fluid ◽  
Raja Erinacea ◽  
Urea Content ◽  
Intracellular Amino Acid ◽  
Trimethylamine Oxide ◽  
Total Amino Acids ◽  
Positive Materials

Little skates, Raja erinacea, and stingrays, Dasyatis americana, were gradually transferred over a period of 4-5 days from full strength to approximatley 50% seawater. Plasma and muscle osmolarity fell. Hematocrits were essentially unchanged. Extracellular fluid volume (ECF) of muscle, estimated as the chloride space, increased 70% during this period. Regulation of muscle cell volume was associated with sharp declines in cellular concentrations of total amino acids (ninhydrin-positive materials) and urea. The osmoregulatory importance of the free amino acid pool in erythrocytes and muscle was a particularly prominent feature in both species. Intracellular amino acid concentration in R. erinacea muscle fell from 214 to 144 mmol/liter during transfer to 50% seawater, urea from 398 to 264, and trimethylamine oxide (TMAO) dropped from 63.9 to 35.8 mmol/liter. TMAO plasma levels were similar in stingray and skate, but muscle TMAO concentrations were much higher in the former. Urea content in stingray plasma greatly exceeded that in R. erinacea-630 and 574 mmol/liter in two specimens-perhaps the highest recorded.

scholarly journals The Effect of Mineral Nutrition on the Content of Free Amino Acids and Amides in Tomato Plants I A Comparison of the Effects of Deficiencies of Copper, Zinc, Manganese, Iron, and Molybdenum

1956 ◽  
Vol 9 (4) ◽  
pp. 539 ◽  
Author(s):  
JV Possingham
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acid ◽  
Mineral Nutrition ◽  
Free Amino Acids ◽  
Free Amino ◽  
Quantitative Estimation ◽  
Acid Fraction ◽  
Tomato Plants ◽  
Copper Zinc

The lovel and the qllHnj~itat,jve compositien of the free amino acid fraction of tomato plants grown in full nutrient and in cultures doficiollt ill zinc, copper, nlallganeso, iron. and molybdenum have beon cletormiuecl. 'I'he methods used in the investigation inelude the quantitative estimation of amino aeids by a technique involving paper chromatogl'l1phy, and the cultm'o of tomato plants in highly purified n utriollt solutions.

The Formation of Homoserine from Methionine in Germinating Peas

1971 ◽  
Vol 49 (7) ◽  
pp. 795-798 ◽  
Author(s):  
D. R. Grant ◽  
E. Voelkert
Keyword(s):  
Carbon Dioxide ◽  
Amino Acids ◽  
Amino Acid ◽  
Organic Acid ◽  
Free Amino Acid ◽  
Free Amino ◽  
Total Activity ◽  
Acid Fraction ◽  
Direct Pathway ◽  
Pea Seedlings

L-Methionine-1-14C was fed through the roots to 6-day-old pea seedlings. After 10 h over 80% of the absorbed radioactivity was recovered in the free amino acid fraction, 8% in the extracted proteins, 5% as carbon dioxide, and 2.2% in the organic acid fractions. Analysis of the amino acids revealed that only 24% of the total activity was recovered as methionine, 40% as homoserine, 10% as isoleucine, and smaller but significant amounts of aspartate, O-acetylhomoserine, and cystathionine. Dilution values strongly imply that aspartate is not an intermediate in the extensive conversion of methionine to homoserine; rather a more direct pathway is involved.

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