Free Amino Acid Metabolism Research Articles

Phytochrome effect on free amino acid metabolism of higher plants

Activated phytochrome lowers the free amino acid pools of all plants investigated by about 15%. The action of red light is preferentially directed to Asp, Glu and Phe. Exogenously supplied Leu-U-(14)C is incorporated more quickly into protein of red-light-treated samples compared with dark controls. In contrast, red light decreases the amount of Asp-U-(14)C incorporated into protein, but increases the amount of (14)CO2 respired after feeding with Asp-U-(14)C. Red light has no effect on the amount of (14)CO2 respired after feeding with Leu-U-(14)C. Red-light-mediated stimulation of incorporation of Leu-U-(14)C into protein occurred within 15 min, well before the red-light-mediated increase in (14)CO2 production following feeding with Asp-U-(14)C could be detected.

2588. Mechanism of carbon disulphide neurotoxicity: Tarkowski, S. & Cremer, Jill E. (1972). Metabolism of glucose and free amino acids in brain, studied with 14C-labelled glucose and butyrate in rats intoxicated with carbon disulphide. J. Neurochem.19, 2631

2588. Mechanism of carbon disulphide neurotoxicity: Tarkowski, S. & Cremer, Jill E. (1972). Metabolism of glucose and free amino acids in brain, studied with 14C-labelled glucose and butyrate in rats intoxicated with carbon disulphide. J. Neurochem.19, 2631

Free amino acids in congestive heart failure

Free amino acids were quantitatively analyzed in cardiac muscle and plasma of dogs with chronic congestive heart failure produced by progressive pulmonary artery stenosis. Right ventricular systolic pressure increased from 32 to 89 mmHg and right ventricular end diastolic pressure from 3 to 15 mmHg following chronic constriction of the pulmonary artery. The ratio of right to left ventricular weight approximately doubled (30% vs. 63%) while percent dry weight (21%) did not change in failing hearts. The concentration of plasma and left ventricular amino acids were the same in control and experimental animals. The total free amino acid pool of the failing right ventricle appeared to increase and a significant alteration was seen in methionine concentration (0.111 ± 0.047 vs. 0.523 ± 0.081 μmol/g dry weight). A large change was found in the concentration of taurine (2-aminoethanesulfonic acid) in right ventricles (32.8 ± 3.4 vs. 126 ± 10 μmol/g dry weight) while the same compound was not altered in left ventricles. Myocardial free amino acid metabolism, as judged by endogenous concentrations, was not greatly influenced by chronic heart failure although failing right ventricles seemed to have an expanded pool. Specifically, the large increase in taurine concentration, which was confined to the failing right ventricle, may have functional significance since this compound has been linked to cellular calcium ion movement.

Investigation of the free amino acid metabolism in the embryo of the milkweed bug: Oncopeltus fasciatus

1. 1. Paper chromatography was used to ascertain the amino acid levels in the developing eggs of the milkweed bug: Oncopeltus fasciatus. 2. 2. There were varitions in the concentrations of the amino acids: cystine, proline, alanine, serine, tyrosine and valine-leucine. 3. 3. Serine, tyrosine and valine-leucine increased with time, while alanine and cystine stayed at a relatively steady level. 4. 4. In addition to the amino acid some ultraviolet-emitting substances and possible peptides were found.

2588. Mechanism of carbon disulphide neurotoxicity: Tarkowski, S. & Cremer, Jill E. (1972). Metabolism of glucose and free amino acids in brain, studied with 14C-labelled glucose and butyrate in rats intoxicated with carbon disulphide. J. Neurochem.19, 2631

2588. Mechanism of carbon disulphide neurotoxicity: Tarkowski, S. & Cremer, Jill E. (1972). Metabolism of glucose and free amino acids in brain, studied with 14C-labelled glucose and butyrate in rats intoxicated with carbon disulphide. J. Neurochem.19, 2631

Studies on the Metabolism of Free Amino Acids during Maturation and Ripening of Tomato Fruits

The experiments were carried out to clarify the metabolism of glutamic acid (Glu) and γ-aminobutyric acid (γ-ABA) and the changes of their metabolism during the ripening of tomato fruits. As a result of the experiment using L-Glu-14C (U) and γ-ABA-1-14C in tomato slices, Glu was converted into γ-ABA by decarboxylation and γ-ABA was metabolized into the acids in TCA cycle. The 14C-activity incorporated in the acids from γ-ABA-1-14C was higher in succinic and malic acids. This incorporation rate was higher in immature stages and decreased with ripening.These results suggested that the metabolic pathway of Glu to succinate via γ- ABA (and succinic semialdehyde) existed and this pathway might play an important role in ripening process of tomato fruits as a by-pass of the α-ketoglutarate-suc cinate step of the TCA cycle.

Studies on the metabolism of free amino acids during maturation and ripening of tomato fruits

The experiment was carried out to determine the changes of free amino acids during the ripening of tomato fruits and in parthenocarpic tomato fruits induced by auxins (4-chlro-2-hydroxylmethylphenoxyacetic acid and p-chlorophenoxyacetic acid). The tomato fruits used were‘Fukuju No.2’grown in the field, and‘Yozu’and‘Fukuju No.2’grown in the greenhouse. Ripening test was made with the fruits which were harvested at mature green stage and stored at 20°C. Auxins were sprayed on the fourth cluster of greenhouse grown‘Fukuju No.2’ and the fruits were harvested at table ripe stage and analyzed.In‘Fukuju No.2’fruits grown in the field, γ-aminobutyric acid, serine, glutamic and aspartic acids were present predominantly at the start of the experiment (breaker stage). γ-Aminobutyric acid decreased about 1/3 of the initial content during ripening, and glutamic and aspartic acids increased approximately 3.5 and 2.5 fold respectively. Leucine, iso-leucine and valine decreased slightly, and a small amount of proline and methionine was detected in over ripened fruits.In‘Yozu’fruits grown in the greenhouse, the amounts of amino acids were generally less than in ‘Fukuju No.2’fruits.‘Yozu’fruits have a smaller amount of γ-aminobutyric acid as compared with ‘Fukuju No.2’fruits grown in the field and the content was almost constant during ripening, while glutamic and aspartic acids increased considerably as the fruits ripened.The parthenocarpic tomato fruits were found to contain less amino acids than the control ones with, the exception of glutamic acid and serine fraction.

The role of renal metabolism of free amino acids in achieving the external form of the kidney.

The role of renal metabolism of free amino acids in achieving the external form of the kidney.

Studies on the metabolism of free amino acids during maturation and ripening of tomato fruits

Studies on the metabolism of free amino acids during maturation and ripening of tomato fruits

Dynamics of amino acids in pea stem sections during root formation and its inhibition by kinetin and ethionine

An investigation was conducted to study the interrelation of free amino acid metabolism and root formation in etiolated pea stem sections as dependent on time and on inhibition of root formation by kinetin and ethionine. The rise in the level of aspartic acid and increase in the rate of conversion of14C-labeled glucose to free amino acids were found to be characteristic features of the formation of foci of meristematic cells in pericyclo region. The formation of roots was reflected, in general, much more in the rate of conversion of labeled glucose to free amino acids than in the levels of corresponding amino acids. The total amount of free amino acids was not significantly changed during incubation of stem sections in a solution of kinetin (5×10−5 m). A rapid fall in their level was recorded in the next 24 hours. The incorporation of14C from glucose into a precursor of lignin, phenylalanine, was completely inhibited by kinetin which stimulated simultanously the growth of adjacent buds. Stimulation of secondary xylem formation, which appeared later, was accompanied by the resumption of14C-incorporation into phenylalanine. Inhibition of root formation by ethionine resulted in the rapid fall of the level of most amino acids and in a significant decrease in the rate of incorporation of14C from glucose into amino acids. A decreasing level of ethionine in tissues during cultivation of ethionine-treated stem sections was accompanied by a gradual rise in the individual amino acids and in the rate of conversion of glucose into free amino acids.

The metabolism of free amino acids by washed suspensions of the rumen ciliate Entodinium caudatum.

Surmmary Washed suspensions of Entodinium caudatum, grown in vitro, incubated anaerobically in the presence of penicillin and neomycin, incorporated single amino acids into the cell protein without conversion to any other amino acid. The 14C-labelled components of the protozoal ‘pool’ and the medium were also investigated but no extensive catabolism of the amino acids observed. At low external concentrations the amino acids were taken up by an ‘active’ process, but above a critical concentration the amino acids entered the cell by passive diffusion and they have been divided into two groups depending on whether this critical concentration was approximately 0–0001 M or 0–001 M. The rate of amino acid uptake was not altered by the presence of inert particulate matter. Of the 75% of the cell volume occupied by liquid, approximately two-thirds was freely available to amino acids.

Some aspects of free amino acid metabolism in developing encysted embroyos of Artemia salania, the brine shirmp

1.1. Free amino acid patterns during the hatching of Artemia depend upon embryonic development and external salinity.2.2. High transaminase activity indicates rapid turnover of alanine, glutamic acid, and aspartic acid. This turnover is probably related to protein reorganization.3.3. Alanine patterns before emerbence are correlated with patterns of enzyme activity and oxygen consumption. A hydroxypyruvate pathway would explain a rapid fall of alanine before emergence.4.4. Amino acids are released into distilled water in greater quantities than the observed loss from Artemia suggesting continuous synthesis and loss of amino acids. The loss depends mainly upon the absence of Na+.5.5. Internal free amino acid levels after emergence are higher in increased salinity, but the increase contributes only slightly to internal osmotic pressure. Ammonia excretion rate in less during the buildup of free amino acids in greater salinities.

Effects in vivo and in vitro of l-glutamic acid-γ-hydrazide on metabolism of some free amino acids in brain and liver

Further research on the effect of l-glutamic acid-γ-hydrazide (GAH) on free amino acids metabolism in brain is reported. Similar studies of free amino acid metabolism in liver are also presented. The addition of GAH to mice brain homogenates inhibited the activities of γ-aminobutyrate aminotransferase (ABAT), and of glutamate decarboxylase (GAD). The activities of alanine aminotransferase (AAA) and of aspartate aminotransferase (ASA) were not affected by GAH in these conditions. Brain homogenates from GAH-treated mice showed lower GAD, ABAT, AAA, and β-alanine-α-ketoglutaric aminotransferase (βAA) activities than brain homogenates from control mice. GAD activity was inhibited by GAH to a considerably lesser extent in vivo than in vitro. In liver, GAH produced a striking increase in the concentrations of almost all the free amino acids, especially of alanine and β-alanine. The addition of GAH to mice liver homogenates inhibited the βAA activity, but neither AAA nor ASA activity was affected by the same concentration of GAH. Liver homogenates from GAH-treated mice showed diminished βAA and AAA activity in comparison with liver homogenates from control mice. Some differences in the conversion of uniformly labeled 14C- glucose to liver and brain free amino acids were found between control and GAH-treated mice. In the brain of the latter animals, aspartic and glutamic acids and glutamine exhibited initially a higher specific activity than in control mice. In the case of γ-aminobutyric acid and alanine, opposite results were obtained. In the GAH-treated animals these two amino acids showed no significant decay of the acquired radioactivity. In liver, the decay of the acquired radioactivity of alanine tended to be slower in GAH-treated animals than in control animals.

Studies on the metabolism of virus-infected tissues. I. Free amino acid metabolism in chick chorioallantoic membranes infected with influenza virus

The propagation of influenza A virus in isolated chick chorio-allantoic membranes is associated with an increased metabolic activity of the free amino acids of the host tissue. The virus-infected tissue showed an increased conversion of glucose-C 14 to glutamic acid, aspartic acid, serine, alanine, and glycine. In tissues prelabeled with glycine-C 14 or alanine-C 14, the addition of virus increased the rate of loss of radioactivity from the free glycine or free alanine, but had no effect on the loss of radioactivity from the corresponding protein-bound amino acids. Virus propagation had no effect on the rate of incorporation of several C 14 amino acids into the mixed proteins of the chorio-allantoic membranes. The possible implications of these results are discussed.

Studies on the Synthesis of Alphaamylase and Free Amino Acids by Mutants of Aspergillus oryzae

SUMMARYThe effectiveness of ultra-violet rays and α radiation from polonium210 in causing mutations affecting the synthesis of α-amylase in 24 industrially important monoconidial isolates of Aspergillus spp. was studied. Mutants were obtained from Aspergillus oryzae (Ahlburg) Cohn, isolate 6A, whose cultures differed from 6A in growth, sporulation and α-amylase activity, α-amylase production by mutants 6A20M1 and 6A20M8 was quantitatively determined by amylograph and dextrinization methods. Isolate 6A20M8 produced more than twice as much α-amylase as the parent isolate 6A. Chromatographic analyses of culture filtrates of the various mutants and parent isolates indicated that mutations which affected amylase synthesis also influenced the metabolism of free amino acids by these fungi.Grateful acknowledgments are made to Robert J. Klug, George C. Papavizas, and John F. Tuite of the Department of Plant Pathology and Botany, and to Neville Prentice of the Department of Agricultural Biochemistry for their assistance in certain phases of this research.

Changes in Distribution of Sulfur-Containing Amino Acids in Developing Grasshopper Egg (Melanoplus differentialis)

Previous articleNext article No AccessChanges in Distribution of Sulfur-Containing Amino Acids in Developing Grasshopper Egg (Melanoplus differentialis)Yu-Ying FuYu-Ying Fu Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Volume 30, Number 1Jan., 1957 Article DOIhttps://doi.org/10.1086/physzool.30.1.30166303 Views: 1Total views on this site Citations: 9Citations are reported from Crossref Journal History This article was published in Physiological Zoology (1928-1998), which is continued by Physiological and Biochemical Zoology (1999-present). Copyright 1957 The University of ChicagoPDF download Crossref reports the following articles citing this article:Vincent H. Favalora, H.G. Kalicki Investigation of the free amino acid metabolism in the embryo of the milkweed bug: Oncopeltus fasciatus, Comparative Biochemistry and Physiology Part B: Comparative Biochemistry 44, no.33 (Mar 1973): 843–847.https://doi.org/10.1016/0305-0491(73)90234-4Milos Kucera, Ralph B. Turner Changes in activity of proteases during embryogenesis of Anagasta kuehniella (insecta), Comparative Biochemistry and Physiology Part B: Comparative Biochemistry 44, no.22 (Feb 1973): 577–585.https://doi.org/10.1016/0305-0491(73)90031-XMILOS KUCERA, RALPH B. TURNER Persistence of a Diurnal Rhythm of Protease Activity after Lethal Heat Treatment of Anagasta Eggs, Nature New Biology 240, no.104104 (Dec 1972): 287–288.https://doi.org/10.1038/newbio240287a0J.R. MacFarlane, T.W. Hogan Free amino acid changes associated with diapause in the egg of the field cricket, Teleogryllus, Journal of Insect Physiology 12, no.1010 (Oct 1966): 1265–1278.https://doi.org/10.1016/0022-1910(66)90017-5P.S. Chen Amino Acid and Protein Metabolism in Insect Development, (Jan 1966): 53–132.https://doi.org/10.1016/S0065-2806(08)60186-1P.S. Chen, H. Briegel Studies on the protein metabolism of Culex Pipiens L.—V. Changes in free amino acids and peptides during embryonic development, Comparative Biochemistry and Physiology 14, no.33 (Mar 1965): 463–473.https://doi.org/10.1016/0010-406X(65)90221-5FRIEDRICH SEIDEL, PAUL KOCH UNTERSUCHUNGEN ZUR KULTUR VON INSEKTENEMBRYONEN IN VITRO, Embryologia 8, no.33 (Aug 1964): 200–222.https://doi.org/10.1111/j.1440-169X.1964.tb00199.xELIZABETH M. DEUCHAR THE ROLES OF AMINO ACIDS IN ANIMAL EMBRYOGENESIS, Biological Reviews 37, no.33 (Aug 1962): 378–416.https://doi.org/10.1111/j.1469-185X.1962.tb01618.xG. Colombo, C.A. Benassi, G. Allegri, E. Longo Free amino-acids in eggs of Schistocerca gregaria forsk. (orthoptera) during development, Comparative Biochemistry and Physiology 5, no.22 (Feb 1962): 83–93.https://doi.org/10.1016/0010-406X(62)90121-4

Metabolism of free amino acids, peptides and proteins in early sea urchin development

Metabolism of free amino acids, peptides and proteins in early sea urchin development

Occurrence and Metabolism of Free Amino Acids during Insect Metamorphosis

Summary. 1 With the partition paper chromatographic method the occurrence of free amino acids in extracts from pupae of Calliphora erythrocephala Meig. (Dipt.) and Phalera bucephala L. (Lep.) were investigated. For both the species principally the same amino acids were found. 2 The amino acid concentration in Calliphora is comparatively constant during the whole development. There are, however, slight minima at 0–20 % and 60–80 % of pupal time. These minima may he put in relation to the histogenesis of hypodermal and muscular tissue, respectively. The Phalera pupae show an increased amino acid concentration during the latent development and a decrease during the suhitan development. 3 By the use of Thunherg's inethylene blue method it was found that during the metimorphosis of Calliphora the enzymatic amino acid oxidation has a maximum activity at the beginning and at the end of the pupil period but is at its minimum in the middle of this period in accordance with the total metabolism. The interrelationship between amino acid oxidation, protein synthesis. and proteolysis is discussed and it is suggested that a minimum protein synthesis exists at the formation of the pupation and at the end of the pupil period, a maximum protein synthesis at pupation and during the histogenesis of the imaginal muscles after the middle of the metamorphosis period, and a relative maximum of proteolysis at 30–50 % of the papal time.