Reproduction Versus Somatic Growth: Hormonal Control in Octopus Vulgaris

1978 ◽  
Vol 77 (1) ◽  
pp. 15-31 ◽  
Author(s):  
R. K. O'DOR ◽  
M. J. WELLS
Keyword(s):  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
Muscle Protein ◽  
Somatic Growth ◽  
Hormonal Control ◽  
Gland Secretion ◽  
Total Amino Acid ◽  
Octopus Vulgaris ◽  
Precocious Maturity

Octopus vulgaris can be forced into precocious maturity by removal of the subpedunculate lobe from the brain, an operation that releases the optic glands from inhibition, and allows them to secrete a gonadotropin. 14C-leucine was injected into the bloodstream of immature animals and its subsequent incorporation into muscle protein followed by taking successive samples from the arms. The optic glands were then activated, and a further injection of 3H-leucine given and followed by means of further arm samples. Optic gland secretion suppresses protein synthesis in the muscles. This is associated with an increase in the total amino acid pool in the muscles and with a considerable increase in the concentration of free amino acids circulating in the blood. If an ovary is present these events are associated with a rapid growth of the ovary and its ducts, and a loss of weight elsewhere. In ovariectomized animals the ducts grow, but there is no yolk to absorb the large pool of free amino acids, and the animals gain weight by osmotic uptake of water into the muscles. The developing ovary may produce a hormone that increases the release of amino acids from muscle, since the concentration circulating in the blood of intact animals remains at least as high as in ovariectomized octopuses, despite the demands of the developing ovary. These matters are discussed in relation to other evidence for a gonadial hormone and in relation to the ‘self-destruct’ effect of the optic gland secretion in determining the post-reproductive death of octopuses.

Factors in Resistance of Peas to the Pea Aphid, Acyrthosiphon pisum (Harr.) (Homoptera: Aphididae). II. Amino Acids

1957 ◽  
Vol 89 (10) ◽  
pp. 457-464 ◽  
Author(s):  
J. L. Auclair ◽  
J. B. Maltais ◽  
J. J. Cartier
Keyword(s):  
Amino Acids ◽  
Paper Chromatography ◽  
Free Amino Acids ◽  
Free Amino ◽  
Acyrthosiphon Pisum ◽  
Quantitative Estimation ◽  
Preliminary Investigation ◽  
Pea Aphid ◽  
Total Amino Acid ◽  
Amino Acid Contents

In field investigations on the relative resistance of varieties of peas, Pisum sativum L., to the pea aphid, Acyrthosiphon pisum (Harr.), the average number of aphids per terminal growth for 13 years (Maltais, 1937, 1950, 1951, and unpublished technical report, 1950-54) for six varieties was as follows: Perfection, 39.6; Daisy, 32.6; Lincoln, 35.6; Laurier (H-103), 9.8; Champion of England, 11.8; and Melting Sugar, 16.8. In a preliminary investigation by Auclair and Maltais (1950), 11 free amino acids were detected in pea plant extracts by paper chromatography. From a visual comparison of chromatograms, the variety Perfection appeared to contain a higher concentration of most free amino acids than the variety Laurier. This is a report on the quantitative estimation of the free and total amino acid contents of the three susceptible varieties (Perfection, Daisy, and Lincoln) and the three resistant varieties (Laurier, Champion of England, and Melting Sugar) by the method of paper chromatography.

scholarly journals Nitrogen Storage and Its Interaction with Carbohydrates of Young Almond Trees in Response to Nitrogen Supply

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 796C-796
Author(s):  
Guihong Bi* ◽  
Carolyn Scagel ◽  
Lailiang Cheng ◽  
Leslie Fuchigami
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Total Amino Acid ◽  
Total N ◽  
N Supply ◽  
N Assimilation ◽  
Predominant Amino Acid ◽  
Total Amino Acids

June-budded `Nonpareil/Nemaguard' almond (Prunus dulcis (Mill) D.A. Webb) trees were fertigated with one of five nitrogen (N) concentrations (0, 5, 10, 15, or 20 mm) in a modified Hoagland's solution from July to September. In October, the trees were sprayed twice with either water or 3% urea, then harvested after natural leaf fall and stored at 2°C. Trees were destructively sampled during winter storage to determine their concentrations of amino acids, protein, and non-structural carbohydrates (TNC). Increasing N supply either via N fertigation during the growing season or with foliar urea applications in the fall increased the concentrations of both free and total amino acids, whereas decreased their C/N ratios. Moreover, as the N supply increased, the proportion of nitrogen stored as free amino acids also increased. However, protein was still the main form of N used for storage. The predominant amino acid in both the free and total amino-acid pools was arginine. Arginin N accounted for an increasing proportion of the total N in both the free and total amino acids as the N supply was increased. However, the proportion of arginine N was higher in the free amino acids than in the total amino acids. A negative relationship was found between total amino acid and non-structural carbohydrate concentrations, suggesting that TNC is increasingly used for N assimilation as the supply of N increases. Urea applications decreased the concentrations of glucose, fructose, and sucrose, but had little influence on concentrations of sorbitol and starch. We conclude that protein is the primary form of storage N, and that arginine is the predominant amino acid. Furthermore, the synthesis of amino acids and proteins comes at the expense of non-structural carbohydrates.

scholarly journals Studies of the chemical composition of a healing skin wound in rats, and of the concentrations of some constituents of tissues distant from the healing wound

1967 ◽  
Vol 102 (3) ◽  
pp. 767-773 ◽  
Author(s):  
J Candlish ◽  
N. Chandra
Keyword(s):  
Amino Acids ◽  
Ascorbic Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Muscle Protein ◽  
Skin Wound ◽  
Neutral Salt ◽  
Polythene Tube ◽  
Healing Wound ◽  
Muscle Water

1. A skin lesion was made in rats by dorsal incision and the insertion of a polythene tube. 2. Over a period of 25 days after wounding, assays were performed for ascorbic acid, DNA, hydroxyproline, methionine, tryptophan, tyrosine and free amino acids in the lesion tissue. 3. The neutral-salt-soluble proteins of the lesion tissue were fractionated on DEAE-Sephadex, with the separation of fibrinogen and gamma-globulin from a serum protein fraction. 4. Over a period of 20 days after wounding, in wounded rats and in controls, assays were conducted for: ascorbic acid in lens and liver, hydroxyproline, soluble protein, methionine and water in muscle and tendon, and free amino acids in muscle. 5. Relative to controls there was a decrease in lens and liver ascorbic acid, a rise in tendon hydroxyproline, a rise in muscle free amino acids, a fall in muscle protein and a rise in tendon and muscle water.

scholarly journals Metabolism of heat-damaged proteins in the rat

1971 ◽  
Vol 26 (2) ◽  
pp. 311-322 ◽  
Author(s):  
J. E. Ford ◽  
C. Shorrock
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Milk Powder ◽  
Skim Milk ◽  
Skim Milk Powder ◽  
Total Amino Acid ◽  
Carbohydrate Complex ◽  
Urinary Peptide

1. Freeze-dried cod muscle and casein were subjected to various conditions of heat treat-ment. Diets containing the different products, or the unheated materials, were given to a group of four adult male rats during successive 48 h periods, and urine was collected during the second 24 h of each 48 h period. A further collection of urine was made from the rats after they had been given protein isolated from heated skim-milk powder. The content and amino acid composition of the ‘peptide’ and ‘free amino acids’ in the urines were determined.2. Heat damage to the cod-fillet protein increased the total urinary excretion of peptide-bound amino acids, from 18·6 to 48·8 µmol/rat.d. The composition of the peptide also changed, and in particular there was a marked increase in lysine, from 2·98 to 20·30 µmol %. Three amino acids - lysine, aspartic acid and glutamic acid - together comprised nearly 70 % of the total amino acid residues. There was a corresponding increase in urinary excretion of free amino acids, from 53·7 to I 14·4 µmol/rat.d. The combined losses of lysine in urinary peptide and free amino acids were 1·5 % of the total lysine ingested, as against 0·3 % for the unheated cod fillet.3. The effects of similar heat treatment of casein on the composition of the urinary peptide and free amino acids were less marked. There was no increase in total urinary peptide excretion and there was a smaller increase in the lysine content of the peptide.4. In urine of rats given protein isolated from heated skim-milk powder, the peptide hydro-lysate was rich in lysine and in furosine, which together comprised 41 mol % of the total amino acid composition. These compounds were presumably formed, together with a smaller quantity of pyridosine, from lysine-carbohydrate complex in the urine. It is probable that, as compared with free lysine, the lysine-carbohydrate complex was absorbed relatively in-efficiently from the rat intestine.5. The findings are discussed in relation to the wider question of the metabolism of the ‚unavailable peptide’ that is released in the course of digestion of heat-damaged protein.

scholarly journals Ingestion of Free Amino Acids as Opposed to Intact Protein Increases Amino Acid Absorption but Does Not Further Augment Postprandial Muscle Protein Synthesis Rates

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 673-673
Author(s):  
Michelle E G Weijzen ◽  
Rob JJ van Gassel ◽  
Imre W K Kouw ◽  
Stefan H M Gorissen ◽  
Marcel CG van de Poll ◽  
...  
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Amino Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Protein Digestion ◽  
Acid Absorption ◽  
Amino Acid Absorption

Abstract Objectives The rate of protein digestion and amino acid absorption determines the postprandial rise in circulating amino acids and, as such, modulates postprandial muscle protein synthesis rates. This study compares protein digestion and amino acid absorption kinetics and the subsequent muscle protein synthetic response following ingestion of intact protein versus an equivalent amount of free, crystalline amino acids. Methods Twenty-four healthy, young subjects (age: 22 ± 3 y, BMI: 23 ± 2 kg·m−2, sex: 12 M/12F) ingested 30 g intrinsically L-[1–13C]-phenylalanine and L-[1–13C]-leucine labeled milk protein (PROT; n = 12) or an equivalent amount of free amino acids (AA; n = 12). In addition, subjects received primed continuous L-[ring-2H5]-phenylalanine, L-[ring-3,5–2H2]-tyrosine, and L-[1–13C]-leucine infusions. Blood samples and muscle biopsies were obtained frequently to assess protein digestion and amino acid absorption kinetics and subsequent muscle protein synthesis rates over a 6 h postprandial period. An unpaired t-test was used to compare overall exogenous phenylalanine release in plasma. For other parameters repeated measures ANOVA were applied to determine differences between groups over time (time as within, and group as between-subjects factor). Data are expressed as mean ± SD. Results Postprandial plasma amino acid concentrations and exogenous phenylalanine appearance rates increased after ingestion of PROT and AA (both, P < 0.001), with a greater increase following ingestion of AA when compared to PROT (time*group interaction P < 0.001). Exogenous phenylalanine release in plasma assessed over the 6 h postprandial period, was greater in AA (76 ± 9%) compared with PROT (59 ± 10%; P < 0.001). Ingestion of AA and PROT strongly increased muscle protein synthesis rates based upon L-[ring-2H5]-phenylalanine (time effect P < 0.001), with no differences between groups (from 0.037 ± 0.015 to 0.053 ± 0.014%·h−1 and from 0.039 ± 0.016 to 0.051 ± 0.010%·h−1, respectively; time*group interaction P = 0.629). Conclusions Ingestion of free amino acids as opposed to intact milk protein is followed by more rapid amino acid absorption and greater postprandial plasma amino acid availability, but this does not further augment postprandial muscle protein synthesis rates. Funding Sources This research did not receive external funding.

Changes in proteins and free and total amino acids of peanuts (Arachis hypogaea) infected with Aspergillus parasiticus

1975 ◽  
Vol 53 (22) ◽  
pp. 2639-2649 ◽  
Author(s):  
John P. Cherry ◽  
Clyde T. Young ◽  
Larry R. Beuchat
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Arachis Hypogaea ◽  
Free Amino Acids ◽  
Free Amino ◽  
Aspergillus Parasiticus ◽  
Amino Acid Content ◽  
Total Amino Acid ◽  
Sequence Of Events ◽  
Total Amino Acids

Protein and amino acid composition of peanuts (Arachis hypogaea L.) inoculated with Aspergillus parasiticus Speare were compared with those of non-infected seeds during an 18-day test period to determine metabolic changes within this interrelationship. The levels of buffer-soluble proteins of infected peanuts decreased rapidly to quantities much lower than those of non-infected seeds shortly after inoculation. Simultaneously, the levels of insoluble proteins increased to quantities greater than those contained in soluble fractions. Gel electrophoresis of soluble extracts from inoculated peanuts showed that proteins were hydrolyzed to many small-molecular-weight components, which eventually disappeared as fungal growth progressed. A corresponding increase in quantity of most free amino acids was observed shortly after inoculation of the peanuts. Major changes in free amino acid content coincided with substantial alterations of proteins in both soluble and insoluble fractions. These data suggested that inoculation of peanuts with A. parasiticus initiated a sequence of events whereby proteins were hydrolyzed first to small polypeptides and (or) insoluble components, then to free amino acids. After extended periods of infection, levels of free amino acids varied from day to day, suggesting that differential utilization of these components by the fungus was occurring. Quantities of total amino acids in whole seeds and soluble and insoluble fractions were different for non-inoculated and inoculated peanuts. Distinct differences were especially notable among samples of these three fractions of inoculated seeds. Differences in total amino acid contents apparently reflect qualitative and quantitative changes in proteins and (or) polypeptides present in various fractions examined during the infection period.

scholarly journals Partial Characterization of a Low-Molecular-Mass Fraction with Cryoprotectant Activity from Jumbo Squid (Dosidicus gigas) Mantle Muscle

2019 ◽  
Vol 57 (1) ◽  
pp. 39-47
Author(s):  
Andrés Álvarez-Armenta ◽  
Ramón Pacheco-Aguilar ◽  
Juan Carlos Ramírez-Suárez ◽  
Susana María Scheuren-Acevedo ◽  
Enrique Márquez-Ríos ◽  
...  
Keyword(s):  
Amino Acids ◽  
Molecular Mass ◽  
Ammonium Chloride ◽  
Free Amino Acids ◽  
Free Amino ◽  
Mass Fraction ◽  
Muscle Protein ◽  
Protein Functionality ◽  
Dosidicus Gigas ◽  
Jumbo Squid

Freezing conditions affect fish muscle protein functionality due to its denaturation/aggregation. However, jumbo squid (Dosidicus gigas) muscle protein functionality remains stable even after freezing, probably due to the presence of low-molecular-mass compounds (LMMC) as cryoprotectants. Thus, water-soluble LMMC (<1 kDa) fraction obtained from jumbo squid muscle was evaluated by Fourier transform infrared spectrometry. From its spectra, total carbohydrates, free monosaccharides, free amino acids and ammonium chloride were determined. Cryoprotectant capacity and protein cryostability conferred by LMMC were investigated by differential scanning calorimetry. Fraction partial characterization showed that the main components are free amino acids (18.84 mg/g), carbohydrates (67.1 µg/mg) such as monosaccharides (51.1 µg/mg of glucose, fucose and arabinose in total) and ammonium chloride (220.4 µg/mg). Arginine, sarcosine and taurine were the main amino acids in the fraction. LMMC, at the mass fraction present in jumbo squid muscle, lowered the water freezing point to –1.2 °C, inhibiting recrystallization at 0.66 °C. Significant myofibrillar protein stabilization by LMMC was observed after a freeze-thaw cycle compared to control (muscle after extraction of LMMC), proving the effectiveness on jumbo squid protein muscle cryo- stability. Osmolytes in LMMC fraction inhibited protein denaturation/aggregation and ice recrystallization, maintaining the muscle structure stable under freezing conditions. LMMC conferred protein cryostability even at the very low mass fraction in the muscle.

scholarly journals The effects of fall fertilization on the growth of Chinese pine and Prince Rupprecht’s larch seedlings

2019 ◽  
Vol 31 (6) ◽  
pp. 2163-2169
Author(s):  
Yan Zhu ◽  
Shan Li ◽  
Caiyun Wang ◽  
R. Kasten Dumroese ◽  
Guolei Li ◽  
...  
Keyword(s):  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
Nutrient Loading ◽  
Nitrogen Loading ◽  
Pinus Tabulaeformis ◽  
Total Amino Acid ◽  
Chinese Pine ◽  
Pine Seedlings ◽  
Amino Acid Contents

Abstract Nutrient loading in the fall is a practical way to improve seedling quality and has been proven to increase nutrient accumulation, translocation and utilization. Few studies have reported on the variation in free amino acids as a result of fall fertilization, especially for different seasonal needle habits (evergreen, deciduous). Therefore, a balanced two-factor factorial design with one fall fertilization treatment (10 mg N/seedling) and Chinese pine (Pinus tabulaeformis Carr.) and Prince Rupprecht’s larch (Larix principis-rupprechtii Mayr.) seedlings was used to examine growth response over one nursery season. Associated changes between fall fertilization, N storage and free amino acids were analyzed. Results showed that: (1) stem height, diameter and biomass for both species were similar between controls and fall fertilization treatments; (2) compared to controls, fall fertilization increased Chinese pine needle and root N by 17.7% and 36.9%, respectively. For Prince Rupprecht’s larch, fall fertilization resulted in 26.3% and 34.54% more N in stem and roots, respectively, than controls; (3) the three main amino acids in control and fertilization treatments in Prince Rupprecht’s larch seedlings were glutamine, arginine and proline, and in Chinese pine seedlings were glutamine, arginine and γ-amino butyric acid; (4) total amino acid contents were not significantly increased by fall fertilization, but glutamine in Chinese pine and Prince Rupprecht’s larch increased by 64.2% and 35.2%, respectively. Aboveground biomass of Prince Rupprecht’s larch had higher proline contents than Chinese pine, which suggests that the stress resistance of the aboveground tissue may be higher for Prince Rupprecht’s larch. The results indicate that different plant organs with various response are well adapted to nitrogen loading for nutrient storage in evergreen and deciduous conifer seedlings.

scholarly journals Measurement of the rates of protein synthesis in rabbits. A method for the estimation of rates of change in the specific radioactivities of free amino acids during continuous infusions

1980 ◽  
Vol 192 (2) ◽  
pp. 623-629 ◽  
Author(s):  
G E Lobley ◽  
S P Robins ◽  
R M Palmer ◽  
I McDonald
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Rate Constants ◽  
Free Amino Acids ◽  
Free Amino ◽  
Muscle Protein ◽  
Specific Radioactivity ◽  
Free Proline ◽  
Rates Of Change ◽  
New Zealand White Rabbits

1. A method is described by which, from analysis of terminal samples, the rate constants that define the changes in specific radioactivity of free amino acids during continuous infusions can be estimated. The method involves the infusion of 3H-labelled and 14C-labelled forms of an amino acid for different, but overlapping, periods. 2. The procedure was developed for infusions of proline and tyrosine into New Zealand White rabbits and the rate constants were determined for blood and muscle. 3. The rate constant for equilibrium of radioactive free proline was much lower in muscle than in blood, and indicated that a plateau condition may not be attained in muscle by the end of a 6 h infusion. 4. Comparison of the ratio of areas under the curves of estimated specific radioactivity plotted versus time with the 3H/14C ratio of bound amino acid in muscle protein suggested that radioactive proline and tyrosine may be incorporated preferentially from an extracellular rather than an intracellular source.

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