THE METABOLISM OF ASCARIS LUMBRICOIDES OVARIES: I. NITROGEN DISTRIBUTION

1955 ◽  
Vol 33 (1) ◽  
pp. 297-306 ◽  
Author(s):  
John K. Pollak ◽  
Donald Fairbairn
Keyword(s):  
Amino Acids ◽  
Ascaris Lumbricoides ◽  
Protein Fraction ◽  
Ammonia Nitrogen ◽  
High Concentration ◽  
Protein Nitrogen ◽  
Amino Amide ◽  
Protein Amino Acids ◽  
High Concentrations ◽  
Reducing Substances

The protein fraction obtained from Ascaris lumbricoides ovaries was analyzed for total, α-amino, and amide nitrogen, as well as amino acids and nucleic acids. In the corresponding non-protein fraction total, α-amino, amide, and ammonia nitrogen, and free amino acids and urea, were determined. Free and protein amino acids were qualitatively similar, but quantitatively dissimilar. Unusually large amounts of proline and alanine were found in the proteins, whereas arginine and methionine could not be identified in protein or free acids. Glutamic acid and alanine comprised one-half of the free acids. Ammonia was present in relatively high concentration, but urea was absent. Much of the non-protein nitrogen was not identified. Ribo- and desoxyribonucleic acids were found in approximately the relative proportions occurring in rat liver, but in much lower concentration. The existence of phosphoproteins was not clearly established. Glycogen and total reducing substances, however, were present initially in high concentrations which decreased markedly when the parasites were maintained in a non-nutrient medium.

THE METABOLISM OF ASCARIS LUMBRICOIDES OVARIES: I. NITROGEN DISTRIBUTION

1955 ◽  
Vol 33 (3) ◽  
pp. 297-306 ◽  
Author(s):  
John K. Pollak ◽  
Donald Fairbairn
Keyword(s):  
Amino Acids ◽  
Ascaris Lumbricoides ◽  
Protein Fraction ◽  
Ammonia Nitrogen ◽  
High Concentration ◽  
Protein Nitrogen ◽  
Amino Amide ◽  
Protein Amino Acids ◽  
High Concentrations ◽  
Reducing Substances

The protein fraction obtained from Ascaris lumbricoides ovaries was analyzed for total, α-amino, and amide nitrogen, as well as amino acids and nucleic acids. In the corresponding non-protein fraction total, α-amino, amide, and ammonia nitrogen, and free amino acids and urea, were determined. Free and protein amino acids were qualitatively similar, but quantitatively dissimilar. Unusually large amounts of proline and alanine were found in the proteins, whereas arginine and methionine could not be identified in protein or free acids. Glutamic acid and alanine comprised one-half of the free acids. Ammonia was present in relatively high concentration, but urea was absent. Much of the non-protein nitrogen was not identified. Ribo- and desoxyribonucleic acids were found in approximately the relative proportions occurring in rat liver, but in much lower concentration. The existence of phosphoproteins was not clearly established. Glycogen and total reducing substances, however, were present initially in high concentrations which decreased markedly when the parasites were maintained in a non-nutrient medium.

scholarly journals A Few Experimental Suggestions Using Minerals to Obtain Peptides with a High Concentration of L-Amino Acids and Protein Amino Acids

Symmetry ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2046
Author(s):  
Dimas A. M. Zaia ◽  
Cássia Thaïs B. V. Zaia
Keyword(s):  
Amino Acids ◽  
Rna World ◽  
High Concentration ◽  
Protein World ◽  
Protein Amino Acids ◽  
Hydrothermal Environment ◽  
World Hypothesis ◽  
Prebiotic Earth ◽  
Hydrothermal Environments ◽  
Selection Of

The peptides/proteins of all living beings on our planet are mostly made up of 19 L-amino acids and glycine, an achiral amino acid. Arising from endogenous and exogenous sources, the seas of the prebiotic Earth could have contained a huge diversity of biomolecules (including amino acids), and precursors of biomolecules. Thus, how were these amino acids selected from the huge number of available amino acids and other molecules? What were the peptides of prebiotic Earth made up of? How were these peptides synthesized? Minerals have been considered for this task, since they can preconcentrate amino acids from dilute solutions, catalyze their polymerization, and even make the chiral selection of them. However, until now, this problem has only been studied in compartmentalized experiments. There are separate experiments showing that minerals preconcentrate amino acids by adsorption or catalyze their polymerization, or separate L-amino acids from D-amino acids. Based on the [GADV]-protein world hypothesis, as well as the relative abundance of amino acids on prebiotic Earth obtained by Zaia, several experiments are suggested. The main goal of these experiments is to show that using minerals it is possible, at least, to obtain peptides whose composition includes a high quantity of L-amino acids and protein amino acids (PAAs). These experiments should be performed using hydrothermal environments and wet/dry cycles. In addition, for hydrothermal environment experiments, it is very important to use one of the suggested artificial seawaters, and for wet/dry environments, it is important to perform the experiments in distilled water and diluted salt solutions. Finally, from these experiments, we suggest that, without an RNA world or even a pre genetic world, a small peptide set could emerge that better resembles modern proteins.

Peptide Cyclization at High Concentration

Synlett ◽  
2020 ◽  
Vol 31 (16) ◽  
pp. 1537-1542
Author(s):  
Monika Raj ◽  
Rachel D. Wills ◽  
Victor T. Adebomi
Keyword(s):  
Amino Acids ◽  
Cyclic Peptides ◽  
High Concentration ◽  
Peptide Cyclization ◽  
Synthetic Strategy ◽  
New Methodologies ◽  
High Concentrations

The emergence of cyclic peptides as pharmaceuticals has led to an eruption of new methodologies for macrocyclization. However, the cyclization of peptides at high concentrations presents a challenge due to the production of side products like dimers and oligomers. This factor is more pronounced with the cyclization of peptides composed of fewer than seven amino acids, thus has created a need for a new synthetic strategy. Herein, we will elucidate a new chemoselective method termed ‘CyClick’ that works in an exclusively intramolecular fashion preventing the formation of commonly occurring side products such as dimers and oligomers, even at relatively high concentration.1 Introduction2 Known Methodologies3 Novel CyClick Chemistry4 Conclusion and Outlook

PROTEIN TURNOVER IN WHEAT AND SNAPDRAGON LEAVES: PRELIMINARY INVESTIGATIONS

1963 ◽  
Vol 41 (7) ◽  
pp. 969-983 ◽  
Author(s):  
J. A. Hellebust ◽  
R. G. S. Bidwell
Keyword(s):  
Amino Acids ◽  
Protein Turnover ◽  
Soluble Sugars ◽  
Turnover Rates ◽  
Time Intervals ◽  
Protein Nitrogen ◽  
Protein Amino Acids ◽  
Specific Activities ◽  
Wheat Leaves ◽  
Biochemical Differentiation

Detached primary wheat leaves and attached cotyledons and primary leaves of snapdragons were allowed to photoassimilate C14O2 for short periods of time. They were subsequently kept in air and samples were taken at various time intervals and analyzed for protein nitrogen, and amounts and total radioactivities of soluble sugars and amino acids and protein amino acids. A method of estimating protein turnover from these data is discussed. Amounts and specific activities of respired carbon were also determined for wheat leaves.Minimum protein turnover rates of about 0.5 to 1.5% per hour were found in rapidly growing snapdragon leaves and in snapdragon cotyledons. Lower rates were found in detached, non-growing wheat leaves and slowly growing snapdragon leaves. Little contribution could have been made by proteins as substrates for respiration in detached wheat leaves. It is suggested that protein turnover in leaves is mainly associated with growth and biochemical differentiation.

Composition and Pesticide and Herbicide Residue Analysis of Fresh and 40-Year-Old Pasteurized Blue Crab (Callinectes sapidus) Meat

1991 ◽  
Vol 54 (4) ◽  
pp. 298-301 ◽  
Author(s):  
N. R. REDDY ◽  
G. J. FLICK ◽  
G. C. ARGANOSA ◽  
R. W. YOUNG
Keyword(s):  
Amino Acids ◽  
Blue Crab ◽  
Callinectes Sapidus ◽  
Residue Analysis ◽  
Amino Acid Content ◽  
Major Protein ◽  
Herbicide Residue ◽  
Protein Amino Acids ◽  
High Concentrations ◽  
Crab Meat

Fresh and 40-year-old pasteurized blue crab (Callinectes sapidus) meat was analyzed for proximate composition, mineral, heavy metal, and amino acid content and volatiles concentration and possible pesticide and herbicide residue levels. Both fresh and 40-year-old meat had similar proximate compositions. The 40-year-old crab meat contained high levels of iron, manganese, copper, and heavy metals compared to the fresh. Recovery of total amino acids was lower from the 40-year-old meat. Aspartic acid, glutamic acid, leucine, lysine, and arginine were the major protein amino acids of fresh and 40-year-old crab meat. The 40-year-old meat contained high concentrations of ethanol and trimethylamine compared to the fresh. No herbicide residues were detected in either of the products. Decomposition products of pesticide DDT were detected at very low levels only in the 40-year-old crab meat.

SOURCES OF CARBON FOR THE SYNTHESIS OF PROTEIN AMINO ACIDS IN ATTACHED PHOTOSYNTHESIZING WHEAT LEAVES

1963 ◽  
Vol 41 (7) ◽  
pp. 985-994 ◽  
Author(s):  
J. A. Hellebust ◽  
R. G. S. Bidwell
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Protein Turnover ◽  
Soluble Sugars ◽  
Protein Nitrogen ◽  
Considerable Portion ◽  
Protein Amino Acids ◽  
Specific Activities ◽  
Wheat Leaves

Attached, rapidly growing wheat leaves were allowed to photoassimilate C14O2 and C12O2 alternately. Samples of leaves were collected after each period of photosynthesis and were analyzed for amounts and total activities of soluble sugars and amino acids, and protein amino acids. The leaves were also analyzed for protein nitrogen and amounts and total activities of respired carbon. Samples of roots were also collected and the amounts, total activities, and specific activities of their soluble compounds were determined. It was possible to calculate from these data the proportions of carbon entering some protein amino acids which came either from soluble amino acid pools or by a direct route from photosynthate, bypassing the soluble pools. More than half of the carbon entering protein-bound serine and glycine was derived from newly assimilated CO2, while protein glutamic acid, aspartic acid, and alanine derived more of their carbon from the soluble amino acid pools. Analysis of the data from roots indicated that a considerable portion of the carbon translocated from the leaves was derived from newly assimilated CO2. There was some indication that protein turnover took place, but it was concluded that proteins could not have contributed significantly as substrates for respiration in these leaves.

PROTEIN AND NONPROTEIN NITROGEN CONTENTS OF SOME OILSEEDS AND PEAS

1973 ◽  
Vol 53 (3) ◽  
pp. 651-657 ◽  
Author(s):  
R. S. BHATTY ◽  
F. W. SOSULSKI ◽  
K. K. WU
Keyword(s):  
Amino Acids ◽  
Carthamus Tinctorius ◽  
Appreciable Amount ◽  
Amide Nitrogen ◽  
Nonprotein Nitrogen ◽  
Dilute Sodium Hydroxide ◽  
Protein Amino Acids ◽  
Pea Proteins ◽  
High Concentrations ◽  
Nitrogen Contents

Nonprotein nitrogen (NPN) was extracted from seven species of oilseeds and three cultivars of peas (Pisum sativum L.) by three methods. Method 1 was extraction of meal nitrogen with dilute sodium hydroxide and removal of alkali-soluble proteins by trichloroacetic acid (TCA) precipitation. Methods 2 and 3 were extractions of meal nitrogen with 70% ethanol and 1% TCA, respectively. The three solvents extracted vastly different quantities of nitrogen from the meals. Method 3 gave the highest values for NPN followed by methods 1 and 2 in that order. The nitrogen extracted by ethanol was probably the true NPN content of the meals because of the lack of solubility of oilseed and pea proteins in this solvent. The oilseed meals contained more amide nitrogen than the peas. None of the meals contained any significant quantities of nitrate nitrogen. Amino acid analysis of NPN fractions of meals obtained by method 1 showed the oilseed meals and peas to contain, in free state, all the protein amino acids except cystine or an appreciable amount of methionine. The NPN fractions of the meals contained, except in safflower (Carthamus tinctorius L.), high quantities of ammonia, glutamic, and aspartic acids. Safflower NPN fraction contained, in addition to ammonia, more proline and alanine than glutamic and aspartic acids. Mustard (Brassica juncea Coss.) and pea NPN fractions also contained high concentrations of arginine. The other protein amino acids were present in trace or relatively small concentrations. The major conclusion drawn from the data was that the NPN of the seed species used in the study was highly variable and depended on the method and solvent of extraction.

scholarly journals ACTION ON FIBROBLASTS OF THE PROTEIN FRACTION OF EMBRYONIC TISSUE EXTRACT

1926 ◽  
Vol 44 (3) ◽  
pp. 387-395 ◽  
Author(s):  
Lillian E. Baker ◽  
Alexis Carrel
Keyword(s):  
Amino Acids ◽  
Protein Fraction ◽  
Nitrogen Concentration ◽  
Embryonic Tissue ◽  
Tissue Extract ◽  
Protein Nitrogen ◽  
Continuous Growth ◽  
Long Time ◽  
Embryo Tissue

The above experiments indicate that the growth-stimulating substance found in embryonic tissue extract, which has been responsible for the continuous growth of fibroblasts in vitro for 14 years, is either protein in nature or closely associated with the protein of the extract and adsorbed by it. If any specific hormone responsible for cell division is present, it is united to the protein or carried along with it in its first precipitation. It seems probable that the tissues utilize this protein for the nitrogen which they build into protoplasm. Whether it is first hydrolyzed before adsorption by the tissues has not been ascertained as yet. It has been shown in other experiments reported in the following paper that the amino acids of the tissue juice do not suffice for the growth of fibroblasts and that hydrolyzed tissue juice is toxic in the same way that a too concentrated mixture of amino acids is toxic. The results of the foregoing experiments may be summarized as follows: 1. Fractionation of embryo tissue juice has shown that it is the protein fraction that contains the activating substance. 2. Tissues continue to grow for a long time in the protein of the extract precipitated by CO2 and at a rate approximately equal to that in the original extract diluted to the same nitrogen concentration. 3. The non-protein nitrogen gives slight stimulation to growth. 4. Purification of the protein by repeated precipitation destroys its growth-promoting properties, but whether this is due to a denaturing of the protein,—which occurs very readily,—or to loss of some substance possibly an enzyme attached to it, has not been ascertained. 5. Preparations of purified proteins from embryonic tissue and egg white have shown no marked nutritive or stimulating action. A number of other pure substances have been tried without effect.

The non-protein nitrogen composition of grass silage:III. The composition of spoilt silages

1971 ◽  
Vol 76 (3) ◽  
pp. 329-336 ◽  
Author(s):  
A. D. Hughes
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Nitrogen Content ◽  
Ammonia Nitrogen ◽  
Water Soluble ◽  
Protein Nitrogen ◽  
High Ph ◽  
Selective Degradation ◽  
Amino Acid Nitrogen ◽  
Three Samples

SUMMARYThe nitrogenous composition of the water soluble, non-protein nitrogen fractions of three samples of high-pH-spoilt silage and one sample of overheated silage were examined in detail. The amino acid nitrogen content of the high-pH-spoilt silages declined with increasing extent of spoilage, due to a selective degradation of the amino acids. Losses of amino acids were associated with proportionate increases in the amount of volatile basic nitrogen. Lower aliphatic amines were not present and it was therefore concluded that the ultimate end product of nitrogen metabolism in high-pH-spoilt silages was ammonia. Only low concentrations of putrefaction products, such as putroscine, cadaverine and histamine were present.The composition of the non-protein nitrogen fraction of the overheated silage was unusual in that the ammonia nitrogen content was high and associated with the complete destruction of certain amino acids. The free amino acid nitrogen content was low but this was partially compensated for by a very high ‘peptide’ nitrogen content. There was no evidence of putrefaction products in this silage.

PROTEIN TURNOVER IN ATTACHED WHEAT AND TOBACCO LEAVES

1964 ◽  
Vol 42 (1) ◽  
pp. 1-12 ◽  
Author(s):  
J. A. Hellebust ◽  
R. G. S. Bidwell
Keyword(s):  
Amino Acids ◽  
Protein Turnover ◽  
Specific Activity ◽  
Soluble Sugars ◽  
Turnover Rates ◽  
Protein Nitrogen ◽  
Tobacco Leaves ◽  
Long Time ◽  
Protein Amino Acids ◽  
Wheat Leaves

Attached primary and secondary wheat leaves were supplied continuously with C14O2 during daily periods of photosynthesis for 3 days. Samples were analyzed for amounts and total activities of respired carbon, soluble sugars and amino acids, protein amino acids, and protein nitrogen. By labelling all possible protein precursors to the same extent it was possible to eliminate doubts about the specific activity of carbon entering protein. Hence turnover rates could be accurately established. Because tobacco leaves last for a long time, it was possible to label their proteins, wait until soluble compounds were at a low specific activity, and then measure turnover of proteins as radioactivity in them decreased.Protein amino acid turnover rates of 0.4–0.5% per hour were obtained in rapidly growing secondary wheat leaves and 0.2–0.3% per hour in non-growing primary wheat leaves. Turnover rates of 0.15–0.2% per hour were found in expanding tobacco leaves, but little or no turnover was found in fully expanded tobacco leaves.It is suggested that protein turnover is a facet of the biochemical differentiation that accompanies development, enlargement, or change in function of an organ without concomitant net protein synthesis.

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