Preparation of polyribosome aminoacyl-transfer ribonucleic acid from the muscle of chick embryos.

A procedure for preparing polyribosome aminoacyl-tRNA free from contamination by supernatant aminoacyl-tRNA and free amino acids is described. Important features of the procedure are the use of acidic buffers to help protect the amino acid-tRNA linkage and the inclusion of sodium dodecyl sulphate, to inhibit ribonuclease activity. The specific radioactivity of polyribosome aminoacyl-tRNA is high within 30s and reaches a maximum in 2 1/2 min, well ahead of polyribosome peptides which, as described by Herrmann et al. (1971), attain maximum specific radioactivity in about 10 min.

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Incorporation of carbon atoms from glucose into free amino acids in brain under normal and altered conditions

Canadian Journal of Biochemistry ◽

10.1139/o70-042 ◽

1970 ◽

Vol 48 (3) ◽

pp. 228-235 ◽

Cited By ~ 83

Author(s):

Y. Yoshino ◽

K. A. C. Elliott

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Aspartic Acid ◽

Free Amino Acids ◽

Free Amino ◽

Acid Level ◽

Specific Activity ◽

Specific Radioactivity ◽

Aminobutyric Acid ◽

Aminooxyacetic Acid

The time course of entry of radioactive carbon from intravenously administered [U-14C]-glucose into free amino acids in the brains of rats has been studied using an automatic amino acid analyzer coupled through a flow cell with a scintillation counter. Radioactivity appeared rapidly in alanine, aspartic acid, glutamic acid, glutamine, and γ-aminobutyric acid as previously shown, and in an unknown ninhydrin-positive substance present in very small amount. Urea, serine, and glycine became slightly radioactive. Four hours after giving the radioactive glucose, the specific activity in all soluble substances was low. In pentobarbital anesthesia, specific radioactivity was increased in alanine and decreased in γ-aminobutyric acid, aspartic and glutamic acids, and glutamine. A high proportion of radioactivity remained in glucose. Under hypoxia, alanine increased in amount but decreased in specific activity, and the specific activities of the other strongly labelled amino acids decreased. The proportion of the total radioactivity found in glucose and lactate increased. During picrotoxin and pentylenetetrazol convulsions, changes occurred which were similar to those under hypoxia. After aminooxyacetic acid administration, the well-known great increase in γ-aminobutyric acid level was found to be accompanied by a decrease in glutamate and also in aspartic acid and alanine, indicating inhibition of the three transaminases concerned. The previously observed brief rapid postmortem increase in the amount of γ-aminobutyric acid was confirmed; alanine also increased briefly but no other amino acid did so. The increased γ-aminobutyric acid had the same specific radioactivity as the original but the extra alanine was less radioactive than the original. When the γ-aminobutyric acid level had been increased by administration of aminooxyacetic acid, the rapid postmortem increase did not occur.

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Measurement of the rates of protein synthesis in rabbits. A method for the estimation of rates of change in the specific radioactivities of free amino acids during continuous infusions

Biochemical Journal ◽

10.1042/bj1920623 ◽

1980 ◽

Vol 192 (2) ◽

pp. 623-629 ◽

Cited By ~ 6

Author(s):

G E Lobley ◽

S P Robins ◽

R M Palmer ◽

I McDonald

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Rate Constants ◽

Free Amino Acids ◽

Free Amino ◽

Muscle Protein ◽

Specific Radioactivity ◽

Free Proline ◽

Rates Of Change ◽

New Zealand White Rabbits

1. A method is described by which, from analysis of terminal samples, the rate constants that define the changes in specific radioactivity of free amino acids during continuous infusions can be estimated. The method involves the infusion of 3H-labelled and 14C-labelled forms of an amino acid for different, but overlapping, periods. 2. The procedure was developed for infusions of proline and tyrosine into New Zealand White rabbits and the rate constants were determined for blood and muscle. 3. The rate constant for equilibrium of radioactive free proline was much lower in muscle than in blood, and indicated that a plateau condition may not be attained in muscle by the end of a 6 h infusion. 4. Comparison of the ratio of areas under the curves of estimated specific radioactivity plotted versus time with the 3H/14C ratio of bound amino acid in muscle protein suggested that radioactive proline and tyrosine may be incorporated preferentially from an extracellular rather than an intracellular source.

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Compartmentation of free amino acids for protein biosynthesis. Influence of diurnal changes in hepatic amino acid concentrations of the composition of the precursor pool charging aminoacyl-transfer ribonucleic acid

Biochemical Journal ◽

10.1042/bj1620257 ◽

1977 ◽

Vol 162 (2) ◽

pp. 257-266 ◽

Cited By ~ 72

Author(s):

A Vidrich ◽

J Airhart ◽

M K Bruno ◽

E A Khairallah

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Free Amino ◽

Protein Biosynthesis ◽

Specific Radioactivity ◽

Diurnal Changes ◽

Unequal Distribution ◽

Precursor Pool ◽

Aminoacyl Transfer ◽

Amino Acid Concentrations

To investigate further the mechanisms by which amino acids are segregated for protein biosynthesis, the distribution of a pulse of [3H]valine was monitored in hepatic amino acid pools at seven intervals in the diurnal cycle of meal-fed rats. Although each condition was characterized by a unique balance between intracellular and extracellular valine, in every case the specific radioactivity of valyl-tRNA at steady state was higher that that of intracellular valine but below the extracellular value. Further, the specific radioactivity of the valyl-tRNA could be accurately predicted if extracellular and intracellular valine were combined in proportions specified by the transmembrane concentration gradient. These observations not only substantiate our earlier conclusions that the amino acids used for protein synthesis do not originate exclusively from either the intracellular or extracellular pools, but also strengthen our theory that the membrane transport system is the physical basis for such compartmentation. On the basis of these data we present a method for measuring the specific radioactivity of the precursor pool for protein biosynthesis in cases where the actual isolation of the aminoacyl-tRNA is not technically feasible, and also suggest a theoretical basis for interpreting the unequal distribution of both total and [3H]valine between intracellular and extracellular fluids.

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Nitrogen from ammonia is as efficient as that from free amino acids or protein for improving growth performance of pigs fed diets deficient in nonessential amino acid nitrogen

Journal of Animal Science ◽

10.2527/jas2016.0959 ◽

2017 ◽

Vol 95 (7) ◽

pp. 3093

Author(s):

W. D. Mansilla ◽

J. K. Htoo ◽

C. F. M. de Lange

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Growth Performance ◽

Free Amino Acids ◽

Free Amino ◽

Amino Acid Nitrogen ◽

Nonessential Amino Acid

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Biochemische Aspekte des Aminosäuren-Stoffwechsels bei Psoriasis vulgaris / Biochemical Aspects of Amino Acid Metabolism in Psoriasis vulgaris

Zeitschrift für Naturforschung C ◽

10.1515/znc-1973-7-816 ◽

1973 ◽

Vol 28 (7-8) ◽

pp. 449-451 ◽

Cited By ~ 2

Author(s):

G. Peter ◽

H. Angst ◽

U. Koch

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Free Amino Acids ◽

Free Amino ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Psoriasis Vulgaris ◽

Normal Subjects ◽

Pathological Process

Free and protein-bound amino acids in serum and scales were investigated. In serum the bound amino acids of psoriatics are significantly higher with exception of Pro, Met, Tyr and Phe in contrast to normal subjects. For free amino acids the differences between normal subjects and psoriatics found in serum and scales are not significant. Results are discussed in relation to the single amino acids and the biochemical correlations are outlined which takes the pathological process as a basis.

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Liver extract and its free amino acids equally stimulate gastric acid secretion

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1980.239.6.g493 ◽

1980 ◽

Vol 239 (6) ◽

pp. G493-G496 ◽

Cited By ~ 5

Author(s):

E. J. Feldman ◽

M. I. Grossman

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Acid Secretion ◽

Gastric Acid Secretion ◽

Free Amino Acid ◽

Free Amino Acids ◽

Free Amino ◽

Liver Extract ◽

Amino Acid Mixture ◽

Acid Mixture

Using intragastric titration in dogs with gastric fistulas, dose-response studies were carried out with liver extract and with a mixture of amino acids that matched the free amino acids found in liver extract. All solutions were adjusted to pH 7.0 and osmolality to 290 mosmol x kg-1. Doses are expressed as the sum of the concentrations of all free amino acids. At each dose studied (free amino acid concentration: 2.8, 5.6, 11, 23, and 45 mM), acid secretion in response to the free amino acid mixture was not significantly different from that of liver extract. The peak response to both liver extract and the free amino acid mixture occurred with the 23-mM dose and represented about 60% of the maximal response to histamine. The serum concentrations of gastrin after liver extract and the amino acid mixture were not significantly different. It is concluded that in dogs with gastric fistula, gastric acid secretion and release of gastrin were not significantly different in response to liver extract and to a mixture of amino acids that simulated the free amino acid content of liver extract.

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