Metabolism of Amino Acids in Plants. I. Changes in the Soluble Amino Acid Fractions of Bushbean Seedlings (Phaseolus vulgaris L.) and the Development of Transaminase Activity

1971 ◽  
Vol 49 (6) ◽  
pp. 709-720 ◽  
Author(s):  
J. C. Forest ◽  
F. Wightman
Keyword(s):  
Amino Acids ◽  
Total Nitrogen ◽  
Total Activity ◽  
Quantitative Composition ◽  
Soluble Nitrogen ◽  
Stages Of Growth ◽  
Etiolated Seedlings ◽  
Protein Amino Acids ◽  
Dark Conditions ◽  
Low Activity

The total nitrogen content of seedlings grown under light or dark conditions remained relatively constant during the first 2 weeks of growth, but there was considerable redistribution of nitrogen from cotyledons to the seedling tissues and appreciable changes occurred in the ratio between insoluble and soluble nitrogen in the different organs. Soluble nitrogen increased in etiolated seedlings to reach 55% of the total nitrogen at 14 days, while in light-grown seedlings the soluble nitrogen reached a peak on the 8th day and thereafter rapidly decreased to 25% of the total nitrogen by the end of 2 weeks. The quantitative composition of the soluble nitrogen fraction, with respect to free protein amino acids, was found to differ considerably, not only between seedlings at different stages of growth, but also between organs taken from seedlings at the same stage of growth under the two light conditions. Asparagine, serine, valine, alanine, and threonine were the amino acids that showed the greatest change in amounts in both types of seedlings. Of the six transaminases investigated, only aspartate, alanine, and asparagine aminotransferase systems showed high total activity. Valine aminotransferase had low activity, and the serine and threonine transaminases were not detected. Development of the different transaminase activities was quite similar in seedlings grown under light or dark conditions. No correlation was observed between the development of transaminase activities and the changes in concentrations of the corresponding free amino acids in these seedlings.

Note. Effect of brining time on proteolytic changes in Idiazábal cheese during ripening / Nota. Cambios proteolíticos durante la maduración del queso Idiazábal por efecto del tiempo en salmuera

1996 ◽  
Vol 2 (5) ◽  
pp. 335-339 ◽  
Author(s):  
F.C. Ibáñez ◽  
A.I. Ordóñez ◽  
M.S. Vicente ◽  
M.I. Torres ◽  
Y. Barcina
Keyword(s):  
Amino Acids ◽  
Glutamic Acid ◽  
Total Nitrogen ◽  
Free Amino Acids ◽  
Free Amino ◽  
Dry Matter ◽  
Electrophoretic Analysis ◽  
Soluble Nitrogen ◽  
Clear Trend ◽  
Protein Nitrogen

Idiazábal cheeses were made employing brining times of 12 h (batch A) and 36 h (batch B). Proteolytic changes in both batches were examined over 270 d of ripening; proteolysis was low in both batches, but lower in batch B than in batch A. Electrophoretic analysis revealed incom plete breakdown of αs and β-caseins at the end of the ripening period, particularly in batch B. The proportion of soluble nitrogen as a percentage of total nitrogen was 17.55% in batch B and 19.48% in batch A, while the proportion of non-protein nitrogen was 11.78% in batch B and 15.16% in batch A. The proportion of non-protein nitrogen as a percentage of soluble nitrogen was 67.17% in batch B and 77.88% in batch A. The free amino acids, the smallest non-protein nitrogen frac tion, attained values of 1203 mg/100 g of dry matter in batch B and 1902 mg/100 g of dry matter in batch A. After 60 d of ripening, the main free amino acids were glutamic acid, valine, leucine, lysine, and phenylalanine in both batches, although levels were higher in the batch with the shorter brining time. There was no clear trend in the non-protein-forming amino acids with either ripening time or brining time.

scholarly journals Studies on the nitrogen compounds of the faeces of dairy cows fed urea as the sole or partial source of nitrogen

1979 ◽  
Vol 51 (1) ◽  
pp. 506-513
Author(s):  
Terttu Ettala ◽  
Matti Kreula
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Dairy Cows ◽  
Acid Hydrolysis ◽  
Free Amino Acid ◽  
Total Nitrogen ◽  
Free Amino ◽  
Diaminopimelic Acid ◽  
Nitrogen Compounds ◽  
Soluble Nitrogen

The nitrogen compounds of the faeces of dairy cows on purified, protein-free feed with urea and small amounts of ammonium salts as the sole source of nitrogen (0-feed). on low-protein feed in which part of the protein was replaced with urea (ULP-feed) and on normal protein-containing feed (NorP-feed) were studied. The total nitrogen contents of the dry matter of the faeces were 2.5 ± 0.7 % on 0-feed, 2.4 ± 0.4 % on ULP-feed and 2.3 ± 0.6 % on NorP-feed. The proportion of urea- and ammonium nitrogen of the total nitrogen was 3.2 ± 2.4, 4.5 ± 2.4 and 3.7 ± 1.8 % respectively, and the proportion of nitrogen soluble in 70 % ethanol 10.9 ± 5.7, 9.9 ± 2.4 and 10.4 ± 3.8 % of the total nitrogen; the proportion of nitrogen in the free amino acid fraction was 4.1 ±2.9 on 0-feed, 1.6 ± 1.4 (P < 0.05) on ULP-feed and 3.2 ± 2.9 % on NorP-feed. The nitrogen insoluble in 70 % ethanol as a proportion of the total nitrogen was 82.3 ± 7.2 on 0-feed, 85.4 ± 5.0 on ULP-feed and 82.3 ± 7.2 % on NorP-feed. Of the total nitrogen of this insoluble fraction, the following proportions were released as amino acids by acid hydrolysis: 62.15 ± 8.5 % on 0-feed, 61.6 ± 10.7 % on ULP-feed and 59.0 ± 13.9% on NorP-feed. (α, Ɛ-diaminopimelic acid was 1.7 ± 0.6, 0.7 ± 0.2 (P < 0.05) and 1.2 ± 0,4 mol % respectively of the total amino acids of the hydrolyzate. The soluble nitrogen fraction was separated into free amino acid and »peptide» fractions, and the amino acid composition of both was determined, the latter after acid hydrolysis

Changes in total nitrogen, protein, amino acids and NH+4 in tissues of bilberry, Vaccinium myrtillus, during the growing season

Ecography ◽  
1990 ◽  
Vol 13 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Pekka Lahdesmaki ◽  
Tuulikki Pakonen ◽  
Esko Saari ◽  
Kari Laine ◽  
Leena Tasanen ◽  
...  
Keyword(s):  
Amino Acids ◽  
Total Nitrogen ◽  
Growing Season ◽  
Vaccinium Myrtillus ◽  
Protein Amino Acids

STUDIES ON WHEAT PLANTS USING CARBON-14 COMPOUNDS: XV. UTILIZATION OF SERINE-1-C14 AND SERINE-3-C14

1961 ◽  
Vol 39 (7) ◽  
pp. 1107-1111 ◽  
Author(s):  
W. B. McConnell ◽  
A. J. Finlayson
Keyword(s):  
Amino Acids ◽  
Specific Activity ◽  
Protein Fractions ◽  
Carbon 14 ◽  
Stages Of Growth ◽  
Protein Amino Acids ◽  
Late Stages ◽  
Carboxyl Carbon ◽  
Soluble Material ◽  
Preferential Incorporation

Thirty-five per cent and 43% of the carbon-14 from DL-serine-1-C14 and L-serine-3-C14, respectively, were found in the mature kernels of wheat plants to which the above tracers were administered by injection into the stem during late stages of growth. Total recoveries of carbon-14 in upper portions of the plant were 40% and 35% respectively. Radioactivity was extensively distributed among major kernel components with protein fractions having a somewhat greater specific activity than starch and ether-soluble material. Carbon-14 from both tracers was incorporated into all of the protein amino acids isolated, notable features being an extensive labelling of carboxyl carbon of glycine when DL-serine-1-C14 was used and preferential incorporation of serine carbon-3 into histidine. The results are in accord with the view that conversion of serine to glycine occurs largely by loss of serine carbon-3 and that little or no glycine is formed from serine via decarboxylation.

scholarly journals The effect of sulphur deficiency and sulphur fertilisation on the nitrogen compounds of timothy

1978 ◽  
Vol 50 (2) ◽  
pp. 137-146
Author(s):  
Terttu Ettala ◽  
Matti Kreula ◽  
Hilkka Tähtinen
Keyword(s):  
Amino Acids ◽  
Aspartic Acid ◽  
Total Nitrogen ◽  
Free Amino Acids ◽  
Free Amino ◽  
Nitrate Nitrogen ◽  
Nitrogen Compounds ◽  
Soluble Nitrogen ◽  
Protein Nitrogen ◽  
Sulphur Deficiency

The effect of sulphur deficiency and sulphur fertilisation on the nitrogen compounds of plants was studied, using timothy as the test species. The samples were obtained from 4 field trials performed in northern Finland. The nitrogen and sulphur treatments in each of these trials were as follows: a) N O, S O, b) N 48, S O, c) N 48, S 34, d) N 96, S O and e) N 96, S 68 kg/ha. Nitrogen was applied as NPK compound fertiliser and sulphur in the form of gypsum. In trials 1and 2 sulphur given in addition to nitrogen increased the yield considerably. The contents of soluble-, protein-, a-amino-, ammonium- and nitrate-nitrogen, as well as the free and peptide- and protein-bound amino acids were determined in the harvested timothy. Nitrogen fertilisation did not have any noticeable effect on the protein-nitrogen content of sulphur-deficient plants, but sulphur fertilisation increased it by an average of 26 % (trial 2). The proportion of soluble nitrogen of the total nitrogen in trials 1 and 2 averaged 50 % with N-fertilisation and 37 % with N+S fertilisation. Sulphur fertilisation decreased the contents of a-amino-, ammonium- and nitrate-nitrogen, and also their proportions of the total nitrogen. In those trials (3 and 4) in which sulphur fertilisation did not increase the yield, the proportion of soluble nitrogen of the total nitrogen was an average of 33 % with all treatments. In sulphur-deficient timothy the content of asparagine and aspartic acid totalled 60 % of the content of free amino acids, and their nitrogen formed about 17% of the total plant nitrogen. The corresponding figures with sulphur fertilisation were 39 % and 3.5 %, and in those trials where there was no sulphur deficiency (trials 3 and 4) on average 27 % and 2.5 %, irrespective of fertilisation. The proportion of soluble nitrogen of the total nitrogen of timothy was closely correlated (r = 0.79***) to the N/S ratio, as was the proportion of asparagine plus aspartic acid of the total free amino acids (r = 0.91***).

scholarly journals Total nitrogen, water-soluble nitrogen and free amino acids profile during ripening of soft cheese enriched with Nigella sativa seed oil

2019 ◽  
Vol 3 (2) ◽  
pp. 90-96 ◽  
Author(s):  
Mara Georgescu ◽  
Ștefania Mariana Raita ◽  
Dana Tăpăloagă
Keyword(s):  
Amino Acids ◽  
Total Nitrogen ◽  
Free Amino Acids ◽  
Free Amino ◽  
Seed Oil ◽  
Nigella Sativa ◽  
Raw Milk ◽  
Water Soluble ◽  
Soluble Nitrogen

AbstractVarious antimicrobial solutions have been tested as additives for raw milk traditional cheeses, among whichNigella sativacold pressed seed oil (NSSO) is recognized for its positive effect on the microbial quality of such products. The overall effect on the quality of enriched cheeses during ripening is still under extensive investigation. Three batches of traditional raw milk brined cheese were included in the current experiment: control cheese withoutNigella sativaseed oil (NSSO) and cheese samples enriched with 0.2 and 1% w/w NSSO. Experimental cheese samples were analyzed in duplicates for total nitrogen content (TN), at 0, 14, 28 and 42 days of ripening, while single determinations of total nitrogen (WSN) and free amino acids (FAA) were performed at 14, 28 and 42 ripening days. The TN content revealed similar values for control cheeses and NSSO cheeses, and no significant differences were noticed within the three treatment groups (p >.05) throughout ripening. WSN values followed a significant rising shift in all cheeses during ripening, yet computing data obtained for the three considered treatments, despite an obvious higher WSN content of NSSO enriched cheeses, no statistical significance could be associated to this difference. The FAA composition of the experimental cheeses, varied quantitatively, by increasing with ripening time, but no qualitative variation was noticed during the follow-up period. The FAA composition of the did not vary significantly within treatments.

Interrelationships among Microbiological, Physicochemical, and Biochemical Properties of Terrincho Cheese, with Emphasis on Biogenic Amines

2004 ◽  
Vol 67 (12) ◽  
pp. 2779-2785 ◽  
Author(s):  
OLIVIA PINHO ◽  
ANA I. E. PINTADO ◽  
ANA M. P. GOMES ◽  
M. MANUELA E. PINTADO ◽  
F. XAVIER MALCATA ◽  
...  
Keyword(s):  
Amino Acids ◽  
Biogenic Amines ◽  
Total Nitrogen ◽  
Free Amino Acids ◽  
Free Amino ◽  
Dry Matter ◽  
Total Content ◽  
Biochemical Properties ◽  
Water Soluble ◽  
Soluble Nitrogen

Changes in the microbiological, physicochemical, and biochemical characteristics of Terrincho cheese as represented by native microflora, pH, water activity, soluble nitrogen fractions, free amino acids, and biogenic amines (e.g., ethylamine, dimethylamine, tryptamine, phenylethylamine, putrescine, cadaverine, histamine, tyramine, cystamine, and spermine) during ripening were monitored. Terrincho is a traditional Portuguese cheese manufactured from raw ewe's milk. The main groups of microorganisms (lactococci, lactobacilli, enterococci, pseudomonads, staphylococci, coliforms, yeasts, and molds) were determined following conventional microbiological procedures. Free amino acids and biogenic amines were determined by reverse-phase high-performance liquid chromatography, following extraction from the cheese matrix and derivatization with dabsyl chloride. The total content of free amino acids ranged from 1,730 mg/kg of dry matter at the beginning of the ripening stage to 5,180 mg/kg of dry matter by day 60 of ripening; such an increase was highly correlated with the increase of water-soluble nitrogen in total nitrogen, 12% trichloroacetic acid–soluble nitrogen in total nitrogen, and 5% phosphotungstic acid–soluble nitrogen in total nitrogen throughout ripening. Histamine was consistently present at very low levels, whereas putrescine, cadaverine, and tryptamine were the dominant biogenic amines and increased in concentration during ripening. Ethylamine, tryptamine, phenylethylamine, and cystamine reached maxima by 30 days of ripening and decreased thereafter. Significant correlations between amino acid precursors and corresponding biogenic amines, as well as between biogenic amines and microbial viable numbers, were observed.

scholarly journals THE NITROGEN DISTRIBUTION IN ALFALFA HAY CUT AT DIFFERENT STAGES OF GROWTH

1938 ◽  
Vol 16c (9) ◽  
pp. 339-346 ◽  
Author(s):  
M. F. Clarke
Keyword(s):  
Protein Synthesis ◽  
Total Nitrogen ◽  
Soluble Nitrogen ◽  
Growing Period ◽  
Stages Of Growth ◽  
Fractional Analysis ◽  
History Of ◽  
Synthesis And Degradation

Analyses were made of alfalfa hays cut at six different stages of growth during the course of one growing season. For the determination of the soluble forms of nitrogen encountered in this study, the method developed by Wasteneys and Borsook for the fractional analysis of incomplete protein hydrolysates was applied. This procedure ensured the securing of more definite information concerning the exact gradations of protein synthesis and breakdown than is obtained by the usual amino and amide nitrogen determinations.The data for total nitrogen show a relatively steady decrease with advancing maturity of the harvested material. Also, the second and third cuttings of hay exhibit a distinctly higher total nitrogen content than the first cutting.Total soluble nitrogen tends to exhibit considerable fluctuation throughout the growing period. Cuts made later in the season show a progressive decrease in the proportionate amounts of this fraction. Particularly striking is the finding that, in all cuttings, total soluble nitrogen tends to be present in very large amounts during the early part of flowering.Results obtained from the application of the method of Wasteneys and Borsook make possible the presentation of a relatively clearly defined pictur of protein synthesis and degradation throughout the growing period. These data further strengthen the assumption that the period between bud formation and the commencement of flowering represents a very critical stage in the life history of the plant.

scholarly journals Nectar non-protein amino acids (NPAAs) do not change nectar palatability but enhance learning and memory in honey bees

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniele Carlesso ◽  
Stefania Smargiassi ◽  
Elisa Pasquini ◽  
Giacomo Bertelli ◽  
David Baracchi
Keyword(s):  
Amino Acids ◽  
Learning And Memory ◽  
Honey Bees ◽  
Feeding Preference ◽  
Memory Retention ◽  
Floral Nectar ◽  
Olfactory Conditioning ◽  
Specific Memory ◽  
Protein Amino Acids ◽  
Valuable Compounds

AbstractFloral nectar is a pivotal element of the intimate relationship between plants and pollinators. Nectars are composed of a plethora of nutritionally valuable compounds but also hundreds of secondary metabolites (SMs) whose function remains elusive. Here we performed a set of behavioural experiments to study whether five ubiquitous nectar non-protein amino acids (NPAAs: β-alanine, GABA, citrulline, ornithine and taurine) interact with gustation, feeding preference, and learning and memory in Apis mellifera. We showed that foragers were unable to discriminate NPAAs from water when only accessing antennal chemo-tactile information and that freely moving bees did not exhibit innate feeding preferences for NPAAs. Also, NPAAs did not alter food consumption or longevity in caged bees over 10 days. Taken together our data suggest that natural concentrations of NPAAs did not alter nectar palatability to bees. Olfactory conditioning assays showed that honey bees were more likely to learn a scent when it signalled a sucrose reward containing either β-alanine or GABA, and that GABA enhanced specific memory retention. Conversely, when ingested two hours prior to conditioning, GABA, β-alanine, and taurine weakened bees’ acquisition performances but not specific memory retention, which was enhanced in the case of β-alanine and taurine. Neither citrulline nor ornithine affected learning and memory. NPAAs in nectars may represent a cooperative strategy adopted by plants to attract beneficial pollinators.

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