Effects of amino acids on the development of spikelets in cultured tassels of Zea mays

1989 ◽  
Vol 67 (5) ◽  
pp. 1331-1335 ◽  
Author(s):  
D. R. Pareddy ◽  
R. I. Greyson
Keyword(s):  
Amino Acids ◽  
Zea Mays ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Inbred Line ◽  
Casein Hydrolysate ◽  
Optimum Concentration ◽  
Differential Effects

The effects of amino acids on spikelet development in in vitro cultured tassels of Zea mays inbred line Oh43 were studied. Single amino acids had differential effects on growth and differentiation of cultured tassels. While a few amino acids (arginine, lysine, valine, and proline) were stimulatory, most of the amino acids were either ineffective (serine, leucine, glycine, threonine, methionine, phenylalanine, histidine, aspartic acid, and tyrosine) or inhibitory (isoleucine, asparagine, tryptophan, glutamic acid, and alanine), at a concentration of 30 mg/L, to the development of "normal" spikelets and also to tassel growth. A mixture of the stimulatory amino acids at their optimal concentrations (arginine, 15 mg/L; lysine, 60 mg/L; valine, 120 mg/L; proline, 15 mg/L) produced the maximum number of "normal" spikelets, thereby duplicating the effect of an optimum concentration of casein hydrolysate.

The oxygen uptake of Trypanosoma lewisi and Trypanosoma equiperdum, with especial reference to oxygen consumption in the presence of amino-acids

Parasitology ◽  
1958 ◽  
Vol 48 (1-2) ◽  
pp. 149-164 ◽  
Author(s):  
June P. Thurston
Keyword(s):  
Amino Acids ◽  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Yeast Extract ◽  
Casein Hydrolysate ◽  
Phosphate Solution ◽  
Trypanosoma Lewisi ◽  
Rate Of Oxygen Consumption

1. Standard conditions are described for preparing suspensions of washed Trypanosoma lewisi and T. equiperdum in modified Ringer–phosphate solution.2. Oxygen consumption was measured with differential manometers, using microflasks containing 2–5 × 107 trypanosomes in 0·9 ml. of reaction mixture. Measurements of oxygen uptake were carried out at 37° C.3. T. lewisi respired slowly in the absence of substrate for up to 2 hr. The trypanosomes suffered little damage when stored at 5° C. for 24 hr. without substrate. No oxygen uptake was observed with T. equiperdum in the absence of substrate. The trypanosomes were viable after 24 hr. at 5° C. with glucose or glycerol as substrate, but not in the absence of substrate.4. With glucose as substrate, the rate of oxygen consumption by T. lewisi increased with the age of infection. This change was more marked with glutamine as substrate.5. With glucosamine as substrate, the oxygen uptake of T. lewisi was at a slightly lower rate than with glucose. The rate of oxygen uptake was still lower with Na l-glutamic acid, asparagine, aspartic acid, casein hydrolysate, yeast extract and Difco Bacto-peptone. Thirteen other amino-acids had no effect on the motility of the trypanosomes.6. With glycerol as substrate, the oxygen uptake of T. equiperdum was at a slightly lower rate than with glucose. The rate of oxygen uptake was very low with yeast extract, casein hydrolysate and Difco Bacto-peptone. No oxygen uptake or motility was recorded with glutamine, Na l-glutamic acid, glucosamine, asparagine, aspartic acid, dl-alanine, or Na acetate. Thirteen other amino-acids had no effect on the motility of the trypanosomes.7. Ammonia was liberated from glutamine by adult and reproductive phase T. lewisi.

Amino acid content of rat renal cortex and the response to in vitro incubation

1979 ◽  
Vol 236 (4) ◽  
pp. F398-F404
Author(s):  
B. Blazer-Yost ◽  
R. Reynolds ◽  
S. Segal
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Room Temperature ◽  
Renal Cortex ◽  
Adult Tissue ◽  
Fresh Tissue ◽  
Cortical Slices

The concentration of aspartic acid, threonine, serine, glycine, and alanine is significantly higher in newborn rat renal cortex than in the adult tissue, while phenylalanine and histidine are higher in the adult. When adult cortical slices are placed in bicarbonate buffer at room temperature for 20 min there is a 30-60% decrease in the levels of all amino acids except for lysine, which is slightly higher, and methionine and serine, which do not change. Under the same conditions, newborn cortical slices reveal a similar decrease in only glycine, tyrosine, histidine, and the branched-chain amino acids. On subsequent in vitro incubation of the cortical slices at 37 degrees C for 120 min the concentrations in adult tissue remain at the lower values observed on removal from buffer at room temperature except that glutamic acid, glycine, and lysine levels decrease further and serine increases to the concentration found in fresh tissue. Newborn tissue when incubated at 37 degrees C for 120 min shows amino acid concentrations comparable to unincubated fresh tissue for all except aspartic acid, glutamic acid, serine, and phenylalanine, which reach levels higher than unincubated tissue. The ability of newborn tissue to maintain amino acid pools may play a role in the enhanced transport of some amino acids resulting from preincubation at 37 degrees C (Reynolds et al. Science 184: 68-69, 1974; Reynolds and Segal, Biochim. Biophys. Acta 406: 513-525, 1976).

Uptake of Dipeptides Containing Basic and Acidic Amino Acids by Rat Small Intestine in Vitro

1972 ◽  
Vol 43 (6) ◽  
pp. 823-837 ◽  
Author(s):  
D. Burston ◽  
Jill M. Addison ◽  
D. M. Matthews
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Tissue Uptake ◽  
Acidic Amino Acids ◽  
Hydrolysis Of

1. The characteristics of transport and hydrolysis of twenty-two dipeptides containing basic and acidic amino acids by rat ileal rings were investigated in vitro. The peptides included combinations of basic and neutral, basic and basic, basic and acidic, acidic and acidic, and acidic and neutral amino acids. 2. All peptides studied were removed intact from the bulk phase of the incubation medium, though, in general, only free amino acids appeared in the tissue. Uptake of one or both constituent amino acids was greater from the peptide than from the equivalent amino acid or amino acid mixture in the case of at least one peptide from each group and in eighteen of the twenty-two peptides studied. In general, there was no relationship between the extent of uptake of amino acids from peptides and the extent of their hydrolysis by the system. The results support the hypothesis that there is more than one mode of uptake of amino acids from peptides. 3. Hydrolysis of γ-glutamyl-l-glutamic acid by intact intestine or intestinal homogenate was slight, and intact peptide was taken up by the tissue. Uptake of free glutamic acid from this peptide was poor. Comparison of γ-glutamyl-l-glutamic acid with three other slowly hydrolysed dipeptides, glycyl-d-valine, sarcosylglycine and glycylsarcosine, suggested that all four were transported into the mucosal cells and hydrolysed intracellularly. The results indicate that the presence of a γ-linkage or a d-amino acid, or methylation of the free amino group as in sarcosylglycine, impair both transport and hydrolysis of peptide, but that attachment of a methyl group to the N of the peptide bond, as in glycylsarcosine, impairs hydrolysis but has no effect on peptide transport. 4. l-Aspartic acid and l-glutamic acid were extensively transaminated by the intestine, whether presented as free amino acids or in peptides. Evidence was obtained suggesting that production of alanine from aspartic acid resulted from direct transamination of aspartic acid with pyruvic acid, rather than from a sequence of two reactions involving aspartate and alanine aminotransferases. 5. The results show that more rapid uptake of amino acids from peptides than from free amino acids is not confined to peptides made up of neutral amino acids, and probably occurs with many small peptides. Uptake of lysine and the dicarboxylic amino acids, which are particularly slowly absorbed from free solution, was much greater from several dipeptides than from the free amino acids. The results suggest the importance of mucosal peptide uptake in protein absorption.

TRANSFORMATION DE L'ACIDE γ-HYDROXYGLUTAMIQUE EN ALANINE ET EN ACIDE GLYOXYLIQUE

1961 ◽  
Vol 39 (10) ◽  
pp. 1595-1603 ◽  
Author(s):  
L. P. Bouthillier ◽  
Y. Binette ◽  
G. Pouliot
Keyword(s):  
Amino Acids ◽  
Comparative Study ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Glyoxylic Acid ◽  
Racemic Mixture ◽  
Animal Tissues ◽  
Direct Formation ◽  
Liver Homogenates

A method is described for the synthesis of γ-hydroxyglutamic-5-C14 acid (racemic mixture). Doses of this substance were administered intraperitoneally to rats and among the amino acids isolated from the tissue proteins, glycine showed the highest radioactivity. This finding is compatible with the postulated theory that γ-hydroxyglutamic acid may be cleaved with the formation of alanine and glyoxylic acid, the latter being normally converted into glycine by amination in the animal tissues. Following the incubation of γ-hydroxyglutamic-5-C14 acid and also γ-hydroxyglutamic-2-C14 acid in the presence of rat liver homogenates, evidence was obtained, by the carrier technique, for the direct formation of radioactive glyoxylic acid and alanine; no trace of glutamic acid or aspartic acid could be detected in the incubation media. As a result of a comparative study of the breakdown in vitro of the racemates of γ-hydroxyglutamic-5-C14 acid, it was found that the isomers of erythro-DL-γ-hydroxyglutamic acid are utilized to a much greater extent than the isomers of threo-DL-γ-hydroxyglutamic acid.

Biodegradation of copoly(L-aspartic acid/L-glutamic acid) in vitro

Biopolymers ◽  
1990 ◽  
Vol 29 (3) ◽  
pp. 549-557 ◽  
Author(s):  
Toshio Hayashi ◽  
Makoto Iwatsuki
Keyword(s):  
Glutamic Acid ◽  
Aspartic Acid

scholarly journals Utilization in vivo of glucose and volatile fatty acids by sheep brain for the synthesis of acidic amino acids

1966 ◽  
Vol 101 (3) ◽  
pp. 591-597 ◽  
Author(s):  
R M O'Neal ◽  
R E Koeppe ◽  
E I Williams
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Specific Activity ◽  
Tricarboxylic Acid Cycle ◽  
Sheep Brain ◽  
The Brain

1. Free glutamic acid, aspartic acid, glutamic acid from glutamine and, in some instances, the glutamic acid from glutathione and the aspartic acid from N-acetyl-aspartic acid were isolated from the brains of sheep and assayed for radioactivity after intravenous injection of [2-(14)C]glucose, [1-(14)C]acetate, [1-(14)C]butyrate or [2-(14)C]propionate. These brain components were also isolated and analysed from rats that had been given [2-(14)C]propionate. The results indicate that, as in rat brain, glucose is by far the best precursor of the free amino acids of sheep brain. 2. Degradation of the glutamate of brain yielded labelling patterns consistent with the proposal that the major route of pyruvate metabolism in brain is via acetyl-CoA, and that the short-chain fatty acids enter the brain without prior metabolism by other tissue and are metabolized in brain via the tricarboxylic acid cycle. 3. When labelled glucose was used as a precursor, glutamate always had a higher specific activity than glutamine; when labelled fatty acids were used, the reverse was true. These findings add support and complexity to the concept of the metabolic; compartmentation' of the free amino acids of brain. 4. The results from experiments with labelled propionate strongly suggest that brain metabolizes propionate via succinate and that this metabolic route may be a limited but important source of dicarboxylic acids in the brain.

scholarly journals Enhancement of aromatase activity by D-aspartic acid in the ovary of the lizard Podarcis s. sicula

Reproduction ◽  
2001 ◽  
pp. 803-808 ◽  
Author(s):  
L Assisi ◽  
V Botte ◽  
A D'Aniello ◽  
MM Di Fiore
Keyword(s):  
Amino Acids ◽  
Aspartic Acid ◽  
Reproductive Cycle ◽  
Catalytic Properties ◽  
Ovarian Tissue ◽  
Experimental Treatment ◽  
Tissue Homogenate ◽  
Aromatase Activity

The present study investigated the role of D-aspartic acid (D-Asp) in ovarian steroidogenesis and its effect on aromatase activity in the lizard, Podarcis s. sicula. It was determined that D-Asp concentrations vary significantly during phases of the reproductive cycle: they vary inversely with testosterone concentrations and directly with oestradiol concentrations in the ovary and plasma. Experimental treatment showed that administration of D-Asp induces a decrease in testosterone and an increase in oestradiol, and that treatment with other amino acids (L-Asp, D-Glu and D-Ala) instead of D-Asp has no effects. Experiments in vitro confirmed these results. Furthermore, these experiments showed an increase in aromatase activity, as the addition of D-Asp either to fresh ovarian tissue homogenate or to acetonic powder of ovarian follicles induced a significant increase in the conversion of testosterone to oestradiol. Aromatase activity is four times greater in the presence of D-Asp than in its absence. However, almost equivalent values of the two K(m) values (both approximately 25 nmol l(-1)) indicate that aromatase has the same catalytic properties in both cases.

scholarly journals The Content of Non-essential Amino Acids in the Grains of Winter and Spring Varieties of Oats (Avena sativa L.) under the Conditions of Central Southern Bulgaria

2013 ◽  
Vol 14 (1) ◽  
pp. 105
Author(s):  
T. Georgieva ◽  
P. Zorovski
Keyword(s):  
Amino Acids ◽  
Glutamic Acid ◽  
G Protein ◽  
Aspartic Acid ◽  
Avena Sativa ◽  
Essential Amino Acids

The purpose of this survey is to study the content of non-essential amino acids in four winter (Dunav 1, Ruse 8, Resor 1, Line M-K) and five spring (Obraztsov chiflik 4, Mina, HiFi, Novosadski golozarnest and Prista 2) cultivars of oats grown in Central Southern Bulgaria within the period from 2007 to 2009. The tested cultivars have different contents of non-essential amino acids. Dunav 1 has the highest quantity of glicine (5.12 g/100 g protein) of all the winter cultivars, Ruse 8 has the highest quantity of alanine (5.69 g/100 g protein) and Resor 1 – the highest quantity of arginine (6.14 g/100 g protein). Generally speaking, the spring cultivars have a larger quantity of glutamic acid (from 25.86 to 26.07 g/100 g protein) and proline (from 6.15 to 8.21 g/100 g protein) but a smaller quantity of glycine (from 4.68 to 4.99 g/100 g protein) compared to the winter cultivars. The naked cultivar Mina has the highest quantity of cystine (2.14 g/100 g protein), cultivar Prista 2 has the highest quantity of proline (8.21 g/100 g protein) and glutamic acid (26.07 g/100g protein) and HiFi ranks first in terms of aspartic acid (9.05 g/100 g protein), serine (5.02 g/100 g protein) and tyrosine (2.09 g/100 g protein). In the study we have also established certain relations between non-essential amino acids.

USE OF GLUTAMIC ACID-U-C14 TO DETERMINE NUTRITIONALLY ESSENTIAL AMINO ACIDS FOR LARVAE OF THE BLOW FLY, PHORMIA REGINA

1960 ◽  
Vol 38 (11) ◽  
pp. 1229-1234 ◽  
Author(s):  
R. Kasting ◽  
A. J. McGinnis
Keyword(s):  
Amino Acids ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Essential Amino Acids ◽  
Phormia Regina ◽  
Blow Fly ◽  
Isoleucine Leucine ◽  
Low Level ◽  
Third Instar Larvae

The production of C14O2 by third-instar larvae of the blow fly, Phormia regina Meig., after it was injected with glutamic acid-U-C14, indicates that this substrate was metabolized under these conditions. However, the nutritionally essential amino acids lysine, phenylalanine, valine, isoleucine, leucine, and threonine, isolated from the injected larvae, contained little radioactivity. A low level of radioactivity in arginine, histidine, and methionine suggests that they were slowly synthesized. The nutritionally non-essential amino acids alanine, serine, aspartic acid, and proline contained large quantities of radioactivity; tyrosine and glycine were exceptions. These results, in agreement with earlier work that used glucose-U-C14, show that radioactivity data are useful for determining certain of the nutritionally essential amino acids.

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