scholarly journals Free amino acids in the xylem sap of pear trees during dormancy

2016 ◽  
Vol 46 (7) ◽  
pp. 1136-1141 ◽  
Author(s):  
Anderson Carlos Marafon ◽  
Flavio Gilberto Herter ◽  
Fernando José Hawerroth ◽  
Adriana Neutzling Bierhals
Keyword(s):  
Amino Acids ◽  
Water Content ◽  
Free Amino Acids ◽  
Free Amino ◽  
Storage Proteins ◽  
Xylem Sap ◽  
Fruit Trees ◽  
Temperate Climate ◽  
Pear Trees ◽  
Effective Use

ABSTRACT: Storage and remobilization are considered key processes for the effective use of nitrogen in temperate fruit trees. As dormancy begins, storage proteins are synthesized, coinciding with a reduction in the levels of free amino acids. Consequently, as dormancy breaks, these storage proteins are degraded, and an increase in the concentrations of amino acids occurs, in order to support new growth. The objective of this study was to evaluate water content of different vegetative tissues (buds, bark, and bole wood), volume of xylem sap, and free amino acid concentrations of xylem sap, during winter dormancy of Hosui Japanese pear trees (VL). Plant material was obtained from the Embrapa Temperate Climate experimental orchard at Pelotas, in the state of Rio Grande do Sul, Brazil. Xylem sap was extracted from the branches with the aid of a vacuum pump, and the free amino acids were determined by gas chromatography, using the EZ kit: Faast GC/FID (Phenomenex). Water content of buds, as well as the volume of sap and concentrations of both aspartic acid and asparagine, substantially increased over time, reaching maximum values in the phase preceding sprouting.

The causes of buoyancy in eggs of marine teleosts

1987 ◽  
Vol 67 (1) ◽  
pp. 169-182 ◽  
Author(s):  
J. C. A. Craik ◽  
S. M. Harvey
Keyword(s):  
Amino Acids ◽  
Water Content ◽  
Free Amino Acids ◽  
Free Amino ◽  
Sea Water ◽  
Inorganic Ions ◽  
Dry Weight ◽  
High Water Content ◽  
Demersal Eggs ◽  
Pelagic Eggs

Pelagic eggs and demersal eggs of teleosts both have osmotic concentrations similar to that of the maternal body fluids, less than half that of sea water. Pelagic eggs are buoyant because they contain such large quantities of this dilute aqueous fluid. While the demersal eggs of teleosts usually have a water content of 60–70%, the buoyant pelagic eggs of marine teleosts such as whiting, Norway pout, saithe, cod, haddock, turbot, dab, plaice, witch, long rough dab, halibut and sole typically have a very high water content (ca. 92 %) and a lipid content of 10–17% of egg dry weight. About 90% of the buoyancy of such eggs in sea water is caused by their high aqueous content, only about 10% being caused by lipid. The buoyant eggs of grenadier and ling have large oil globules and higher lipid contents, 27 and 35 % of dry weight respectively. Nevertheless, most of their buoyancy is provided by their high aqueous contents (89 and 81 % water). The high water content of pelagic eggs is brought about by a massive influx of water into the oocytes during meiotic maturation (ripening) after vitellogenesis but before ovulation. In cod and plaice, ripening is accompanied by a four- to five-fold increase in both water content and free amino-acids, and by a large influx of both potassium and sodium. In cod, free amino-acids contribute much more than these inorganic ions to the water influx and to the total osmotic concentration of the mature egg, but in plaice the relative contribution of inorganic ions approaches that of the free amino-acids.

scholarly journals Seed storage protein changes and mobilization pattern in Bambaranut (Vigna subterranea) (L.) Verdc. during germination

2021 ◽  
Vol 8 (4) ◽  
Author(s):  
Najib M Saminu ◽  
Yusuf Y Muhammad
Keyword(s):  
Amino Acids ◽  
Gibberellic Acid ◽  
Storage Protein ◽  
Free Amino Acids ◽  
Free Amino ◽  
Storage Proteins ◽  
Seed Storage Protein ◽  
Protein Profile ◽  
Seed Storage ◽  
Germination Period

The germination of seeds involves series of events during which mobilization and utilization of seed storage proteins occur. This study is aimed at determining the changes in total and fractions of seed storage protein in six bambaranut landraces during 96 hrs germination period. The study assessed the changes in seed storage protein content, storage protein profile, endopeptidase activity, free amino acids and gibberellic acid levels. Significant (p<0.05) decrease in total storage protein after 24 hrs, albumin from 48 hrs and globulin and glutelin after 72 hrs germination period were observed in the studied landraces. Prolamin showed significant (p<0.05) decrease after 48 hrs in all the landraces. Five peptide bands were detected in the six landraces with molecular weights corresponding to 97.4 kDa, 45 kDa, 29 kDa, 20.1 kDa and 18 kDa. Peptide bands with molecular weight of 97 kDa and 29 kDa decreased in intensity after 48 hrs of germination in four landraces. Free amino acids content significantly (p<0.05) increased following 24 hrs germination period in all the landraces. The activity of endopeptidase increased significantly (p<0.05), reaching maximum after 96 hrs germination. Significant (p<0.05) increase in gibberellic acid level throughout germination period was also observed. Although slow degradation rate of storage proteins was observed, there was variation in the rate at which storage protein and its fractions decreased among the bambaranut landraces during germination. This variation could be utilized towards obtaining improved bambaranut genotypes with better germination characteristics.

Betaines and free amino acids in salt stressed vitroplants and winter resting buds of Populus trichocarpa x deltoides

1991 ◽  
Vol 83 (1) ◽  
pp. 136-143 ◽  
Author(s):  
L. Bray ◽  
D. Chriqui ◽  
K. Gloux ◽  
D. Le Rudulier ◽  
M. Meyer ◽  
...  
Keyword(s):  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
Populus Trichocarpa
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