Free Amino Acids as Affected by Light Intensity and the Relation of Responses to the Shade Tolerance of White Spruce and Shade Intolerance of Jack Pine

1971 ◽  
Vol 1 (3) ◽  
pp. 131-140 ◽  
Author(s):  
D. J. Durzan
Keyword(s):  
Amino Acids ◽  
Light Intensity ◽  
Shade Tolerance ◽  
White Spruce ◽  
Jack Pine ◽  
Soluble Nitrogen ◽  
Natural Light ◽  
Nitrogenous Compounds ◽  
Plant Parts ◽  
Metabolic Basis

Saplings of white spruce and jack pine, grown under field conditions, were exposed for 2 years to natural light, and shade at 45, 25, and 13% of the daily natural light intensity. Continuous shade affected the growth and shape of saplings and influenced metabolism by reducing levels of most nitrogenous compounds in all plant parts (leaves, stems and buds, and roots). Compared with the spruce, significant responses by amino acids to the range of shade treatment in the very intolerant jack pine were greater and covered a much greater proportion of the amino acid N. As saplings were entering winter dormancy, thresholds for significant responses by individual amino acids and intercalation of their metabolic paths with those not responsive reflected a metabolic basis for shade tolerance that represented not only past growth rates of sapling parts, particularly roots, but also the extent to which nitrogenous compounds accumulated and were compartmentalized amongst parts. The main effects of shade on nitrogen metabolism implicated the balance of four- and five-carbon α-keto acids (photosynthate) which evoked significant changes in levels of certain amino acids and the amides, glutamine, and asparagine. At low light intensities, and particularly in stems and buds of both species, soluble nitrogen was diverted into the storage compound arginine.

Nitrogen metabolism of Picea glauca. II. Diurnal changes of free amino acids, amides, and guanidino compounds in roots, buds, and leaves during the onset of dormancy of white spruce saplings

1968 ◽  
Vol 46 (7) ◽  
pp. 921-928 ◽  
Author(s):  
D. J. Durzan
Keyword(s):  
Amino Acids ◽  
Picea Glauca ◽  
Weight Basis ◽  
Aminobutyric Acid ◽  
Soluble Nitrogen ◽  
Diurnal Changes ◽  
Fresh Weight ◽  
Fresh Weight Basis ◽  
Plant Parts ◽  
Guanidino Compounds

In late August during the onset of dormancy in spruce, seasonal levels of soluble nitrogen, rich in arginine, were high. On a fresh weight basis, diurnal levels of total soluble nitrogen and most component amino acids in roots, buds, and leaves showed maxima, one at sunrise and another in the afternoon or near sunset.Arginine and glutamine in the different plant parts contributed 44 to 83% to the alcohol-soluble nitrogen. In buds and leaves, percentage of arginine remained high and decreased slightly at midday, whereas in roots a continual drop occurred. In all organs examined, changes in glutamine reflected the double maxima of total soluble nitrogen and were greatest in roots.On a fresh weight basis, most amino acids accumulated at sunrise and near sunset; however a few especially in leaves, increased at midday, e.g. glutamic and aspartic acid, lysine, γ-aminobutyric acid, and serine.Comparison of levels of free guanidino compounds in different organs showed remarkable out-of-phase patterns. Levels of these compounds are known from 14C-arginine studies to be closely related to the metabolism of arginine.

Free sugars, amino acids, and soluble proteins in the embryo and female gametophyte of jack pine as related to climate at the seed source

1968 ◽  
Vol 46 (4) ◽  
pp. 417-428 ◽  
Author(s):  
D. J. Durzan ◽  
V. Chalupa
Keyword(s):  
Amino Acids ◽  
Female Gametophyte ◽  
Climatic Factors ◽  
Protein Pattern ◽  
Jack Pine ◽  
Soluble Proteins ◽  
Seed Source ◽  
Chemical Components ◽  
Free Sugars ◽  
Nitrogenous Compounds

Non-stratified and dormant seeds from various geographic sources across the natural range of jack pine (Pinus banksiana Lamb.) were separated into embryo (diploid) and female gametophyte (haploid) and examined for their free sugars, free and bound amino acids, and soluble proteins. Climatic factors from not less than 8 and as many as 15 widely separated seed sources correlated well with most chemical components of the embryo and gametophyte. The composition of the dormant embryo was also highly correlated to levels of sugars and nitrogenous compounds in the female gametophyte. Climate at the seed source clearly affected the degree to which metabolism of carbon and nitrogenous compounds in the seed proceeded before and during incipient germination. Upon germination of seeds from one of the sources, the gametophyte was rapidly consumed, arginine level and protein pattern in the embryo changed, many soluble proteins disappeared and amide content increased greatly.

Nitrogen metabolism of Picea glauca. I. Seasonal changes of free amino acids in buds, shoot apices, and leaves, and the metabolism of uniformly labelled 14C-L-arginine by buds during the onset of dormancy

1968 ◽  
Vol 46 (7) ◽  
pp. 909-919 ◽  
Author(s):  
D. J. Durzan
Keyword(s):  
Amino Acids ◽  
Nitrogen Metabolism ◽  
Picea Glauca ◽  
Seasonal Changes ◽  
Late Summer ◽  
Soluble Nitrogen ◽  
Shoot Apices ◽  
Nitrogenous Compounds ◽  
Carbon And Nitrogen ◽  
Carbon And Nitrogen Metabolism

Buds, shoot apices, and leaves from terminal shoots of white spruce saplings accumulated high levels of alcohol-soluble nitrogen in spring, late summer, and early winter. Major components, e.g. arginine, glutamine and proline, of the soluble nitrogen showed patterns complementary to each other. These changes represented the storage and mobilization of nitrogenous compounds during the onset of dormancy or the growth of shoots. Leaves contained less total soluble nitrogen than buds or shoot apices. Soluble nitrogen and arginine content of leaves resembled buds in their seasonal patterns but changes in aspartic acid, glutamic acid, and alanine were much greater than in buds, especially in late summer.When the first frost appeared, uniformly labelled 14C-arginine, applied to the apices of buds, readily entered newly synthesized protein, and free arginine was converted to proline via ornithine. Proline with carbon derived from arginine also entered proteins that were metabolized at different rates. A fraction of the proline in protein was hydroxylated to hydroxyproline. Although traces of 14C-citrulline were detected, more carbon was metabolized to free guanidino compounds, e.g. α-keto-δ-guanidinovaleric acid, γ-guanidinobutyric acid, and several monosubstituted guanidines. After 24 hours, labelled arginine, proline, and γ-guanidinobutyric acid moved down the shoot to the leaves. These metabolic changes in buds show that many of the seasonal changes in amino acids are intimately related to the carbon and nitrogen metabolism of arginine.

scholarly journals Composition of the Nitrogen Fraction of Apple Tracheal Sap

1957 ◽  
Vol 10 (3) ◽  
pp. 279 ◽  
Author(s):  
EG Bollard
Keyword(s):  
Amino Acids ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Growing Season ◽  
Soluble Nitrogen ◽  
Apple Variety ◽  
Nitrogenous Compounds ◽  
Manurial Treatment

Organic nitrogenous compounds accounted for most of the nitrogen present in apple tracheal sap. Aspartic acid, asparagine, and glutamine were quantitatively the most important compounds. Glutamic acid and other amino acids were also present as well as a peptide-like substance. While apple variety, rootstock, or manurial treatment may have had effects on level of nitrogen in tracheal sap they seem to have had little effect on proportions of nitrogenous compounds present. Through the growing season, however, there was a definite change in proportions of some of the constituents. The composition of the soluble� nitrogen fraction of leaves and fruits showed distinct differences from the composition of tracheal sap.

scholarly journals CO2 Enriched Air Increased Growth of Conifer Seedlings

1970 ◽  
Vol 46 (3) ◽  
pp. 229-230 ◽  
Author(s):  
C. W. Yeatman
Keyword(s):  
Light Intensity ◽  
Norway Spruce ◽  
Scots Pine ◽  
Dry Weight ◽  
White Spruce ◽  
Jack Pine ◽  
Tree Seedlings ◽  
Short Term ◽  
Conifer Seedlings

The dry weight of 3-week-old seedlings of white spruce, Norway spruce, jack pine and Scots pine was 30–80% greater than the control when grown in atmospheres enriched 3- to 5-fold with carbondioxide. Seedlings also responded positively to a difference in light intensity. CO2 enriched atmospheres might profitably be used for the short term propagation of tree seedlings grown in greenhouses.

scholarly journals Arginine and the shade tolerance of white spruce saplings entering winter dormancy

2010 ◽  
Vol 56 (No. 2) ◽  
pp. 77-83 ◽  
Author(s):  
J. Durzan D
Keyword(s):  
Amino Acid ◽  
Free Amino ◽  
Shade Tolerance ◽  
Growth Habit ◽  
White Spruce ◽  
Carbon Gain ◽  
Natural Light ◽  
Winter Dormancy ◽  
Guanidino Compounds ◽  
N Metabolism

Shade-tolerant white spruce saplings grown at 100, 45, 25, and 13% natural light for four years, and entering winter dormancy, modified their growth habit and redistributed the total soluble N among needles, roots, and stems with buds mainly to arginine N. Most free amino acid N was found in roots in saplings at full light, and the least at 13% light. Glutamate, glutamine, and aspartate N contributed to the accumulation of soluble arginine N. Arginine-derived γ-guanidinobutyric acid, agmatine and an unidentified guanidino compound accumulated mainly in stems with buds at 25 and 13% light. The profiling N metabolism and arginine-derived guanidino compounds extend models for shade tolerance based mainly on photosynthesis, respiration and carbon gain.

The incorporation of tritiated water into amino acids in the presence of urea by white spruce seedlings in light and darkness

1973 ◽  
Vol 51 (2) ◽  
pp. 351-358 ◽  
Author(s):  
D. J. Durzan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Covalent Binding ◽  
Tritiated Water ◽  
Continuous Light ◽  
White Spruce ◽  
Aminobutyric Acid ◽  
Soluble Nitrogen ◽  
Pyrrolidone Carboxylic Acid

White spruce seedlings containing urease were exposed to 0.16 M urea for 4 h in continuous light. Seedlings accumulated total soluble nitrogen as amides and arginine, and increased their content of bound amino acid nitrogen. In darkness, total soluble nitrogen declined and the increase of total bound amino acids was not as great as in light. In both treatments, the fate of tritiated water was examined by recovery of nonexchangeable tritium from amino acids. As urea was consumed, more tritium was recovered from seedlings in light than in darkness. In both treatments tritium followed the nitrogen of urea and was bound covalently, initially in glutamic acid, and subsequently wherever an α-keto acid was a precursor for the synthesis of the corresponding amino acid, viz. alanine and aspartic acid. In light, tritium was recovered mainly from glutamic acid, followed by glutamine, and to a lesser extent by γ-aminobutyric acid. In darkness, while glutamic acid was prominent initially, more radioactivity was recovered from γ-aminobutyric and glutamic acids compared to glutamine and to the light treatment. Glutamic acid was the main bound amino acid containing covalent tritium.The occurrence of tritium at the α-carbon of glutamic acid was supported by transfer of this tritium after decarboxylation to γ-aminobutyric acid, and by conversion of bound glutamate-3H to radioactive pyrrolidone carboxylic acid during acid hydrolysis of protein.Although urea nitrogen contributed to arginine synthesis in light, no tritium was found in arginine nor its precursors in the ornithine cycle until later, when nearly all amino acids were radioactive. This is consistent with the absence of covalent binding of tritium in ureido precursors leading to arginine biosynthesis, and supports the idea that tritium did not readily follow the carbon of urea into covalent linkage.

Gastrointestinal Interaction between Dietary Amino Acids and Gut Microbiota: With Special Emphasis on Host Nutrition

2020 ◽  
Vol 21 (8) ◽  
pp. 785-798 ◽  
Author(s):  
Abedin Abdallah ◽  
Evera Elemba ◽  
Qingzhen Zhong ◽  
Zewei Sun
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Immune System ◽  
Gut Microbiota ◽  
Short Chain Fatty Acids ◽  
Nutrition And Health ◽  
Nitrogenous Compounds ◽  
Dietary Amino Acids ◽  
Host Nutrition ◽  
Chain Fatty Acids

The gastrointestinal tract (GIT) of humans and animals is host to a complex community of different microorganisms whose activities significantly influence host nutrition and health through enhanced metabolic capabilities, protection against pathogens, and regulation of the gastrointestinal development and immune system. New molecular technologies and concepts have revealed distinct interactions between the gut microbiota and dietary amino acids (AAs) especially in relation to AA metabolism and utilization in resident bacteria in the digestive tract, and these interactions may play significant roles in host nutrition and health as well as the efficiency of dietary AA supplementation. After the protein is digested and AAs and peptides are absorbed in the small intestine, significant levels of endogenous and exogenous nitrogenous compounds enter the large intestine through the ileocaecal junction. Once they move in the colonic lumen, these compounds are not markedly absorbed by the large intestinal mucosa, but undergo intense proteolysis by colonic microbiota leading to the release of peptides and AAs and result in the production of numerous bacterial metabolites such as ammonia, amines, short-chain fatty acids (SCFAs), branched-chain fatty acids (BCFAs), hydrogen sulfide, organic acids, and phenols. These metabolites influence various signaling pathways in epithelial cells, regulate the mucosal immune system in the host, and modulate gene expression of bacteria which results in the synthesis of enzymes associated with AA metabolism. This review aims to summarize the current literature relating to how the interactions between dietary amino acids and gut microbiota may promote host nutrition and health.

On the Nutrition and metabolism of zooplankton IV. The forms of nitrogen excreted By Calanus

1967 ◽  
Vol 47 (1) ◽  
pp. 113-120 ◽  
Author(s):  
E. D. S. Corner ◽  
B. S. Newell
Keyword(s):  
Amino Acids ◽  
Positive Reaction ◽  
Laboratory Experiments ◽  
Long Island Sound ◽  
Acartia Tonsa ◽  
Nitrogenous Compounds ◽  
Nitrogenous Substances ◽  
Experimental Density ◽  
Island Sound ◽  
Calanus Helgolandicus

A study has been made of the nitrogenous compounds excreted by Calanus helgolandicus (Claus) collected at Plymouth.Most of the excreted nitrogen is in the form of ammonia which accounts for 60–100% (average 74.3%) of the total, and some of the remainder may be lost as urea. There is no evidence for the excretion of measurable amounts of amino acids.Whether the animals are starved or fed they are primarily ammonotelic, and the quantity of ammonia produced at 10° C (3.33 μg/g. dry body wt/day) is not significantly changed when the animals are used at an abnormally high experimental density. This latter condition does, however, lead to the production of large quantities of additional nitrogenous substances that give a positive reaction with ninhydrin.IntroductionThe amounts of nitrogen excreted by zooplankton have been measured by several workers. Harris (1959) used the method of Riley (1953) to estimate the copious quantities of ammonia produced by animals (mainly Acartia tonsa and A. clausi) collected from Long Island Sound; Beers (1964), in laboratory experiments with the chaetognath Sagitta hispida, estimated the excreted ammonia by the procedure of Kruse & Mellon (1952); and Corner, Cowey & Marshall (1965) determined the ammonia excreted by Calanus helgolandicus and C. finmarchicus, using a ninhydrin technique described by Moore & Stein (1954). The methods employed by Harris and by Beers are specific for ammonia: that used by Corner et al. estimates nitrogenous substances (e.g. amino acids) in addition to ammonia, but certain tests were made which seemed to exclude the possibility that these substances contributed significantly to the nitrogen excreted by the animals.

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