scholarly journals An investigation of the hyperaminoaciduria in phenylketonuria associated with the feeding of certain commercial low-phenylalanine preparations

1970 ◽  
Vol 24 (2) ◽  
pp. 573-580 ◽  
Author(s):  
Barbara E. Clayton ◽  
A. F. Heeley ◽  
Mary Heeley
Keyword(s):  
Amino Acids ◽  
Acid Hydrolysate ◽  
Isomer Content

1. Hypertryptophanaemia, hypertryptophanuria and to a lesser degree a generalized hyperaminoaciduria were observed in phenylketonuric patients receiving certain commercial low-phenylalanine diets containing DL-tryptophan.2. The generalized hyperaminoaciduria was associated with the ingestion of acid hydro-lysates of protein, but not with the ingestion of enzymic hydrolysates or D-tryptophan.3. Alanine recovered from the urine of these treated patients had a D-isomer content of approx. 50%. This amount of urinary D-alanine could be derived from the ingestion of an acid hydrolysate of protein in which the amino acids had racemized to the extent of 2–3%.

Effects of abomasal infusions of sodium caseinate and of casein hydrolysates varying in the relative proportions of peptides and free amino acids on milk production in dairy cows

1995 ◽  
Vol 62 (3) ◽  
pp. 423-429 ◽  
Author(s):  
Jai-Jun Choung ◽  
David G. Chamberlain
Keyword(s):  
Amino Acids ◽  
Milk Production ◽  
Free Amino Acids ◽  
Free Amino ◽  
Latin Square ◽  
Basal Diet ◽  
Sodium Caseinate ◽  
Acid Hydrolysate ◽  
Lactating Cows ◽  
Stage Of Lactation

SummaryTwo experiments were conducted to test the hypothesis that responses of milk production to the abomasal infusion of casein or hydrolysates of casein can be influenced by the proportion of peptide-bound amino acids in the infusate. Eight lactating cows were used in two Latin square experiments with period lengths of 10 d. In Expt 1, the four cows were at a late stage of lactation and the four treatments were a basal diet of silage and a barley–soya supplement alone or with infusions into the abomasum of 180 g/d of sodium caseinate, an enzymic hydrolysate of casein or an acid hydrolysate of casein; all treatments supplied equivalent amounts of all the amino acids, this being achieved by addition of free amino acids as required. As infused, the three treatments contained 89 (caseinate), 40 (enzymic hydrolysate) and 15 (acid hydrolysate) % of their amino acids as peptides. The increase of milk production in response to infusion was small and there were no significant differences between the infusion treatments. In Expt 2, the cows received a basal diet of grass silage and a supplement containing feather meal as the main source of protein. Treatments were the basal diet alone and with three infusion treatments as in Expt 1, except that the amount infused was 230 g/d. The response to infusion was greater in this experiment, there were significant differences between infusions and the yield of milk protein with the infusion treatments was linearly related (P = 0·001) to the proportion of peptide-bound amino acids in the infusate. Moreover, there was a close inverse relation (P = 0·007) between the proportion of peptide-bound amino acids in the infusate and the concentration of total peptidebound amino acids in blood plasma.

Cultivation of Trypanosoma brucei sspp. in semi-defined and defined media

Parasitology ◽  
1973 ◽  
Vol 67 (3) ◽  
pp. 315-331 ◽  
Author(s):  
G. A. M. Cross ◽  
J. C. Manning
Keyword(s):  
Amino Acids ◽  
Tissue Culture ◽  
Trypanosoma Brucei ◽  
Culture Medium ◽  
Defined Medium ◽  
Tissue Culture Medium ◽  
Optimum Temperature ◽  
Acid Hydrolysate ◽  
Defined Media

Semi-defined and defined media for the growth of culture forms of Trypanosoma brucei sspp. have been developed by enrichment of tissue culture medium 199 with additional vitamins, amino acids, salts and other compounds. The semi-defined medium contains an acid hydrolysate of casein: in the empirically devised defined medium the casein requirement has been circumvented by inclusion of additional vitamins and amino acids. Both media are very hypertonic. Control of pH was found to be particularly critical for growth. The optimum temperature for growth in the semidefined medium was between 25°C and 28°C, but cells would undergo one or two division cycles at 37°C.

Induction et repression de la synthèse de collagénase chez Acinetobacter sp.

1979 ◽  
Vol 25 (5) ◽  
pp. 611-617 ◽  
Author(s):  
Jean-Claude Monboisse ◽  
Jean Labadie ◽  
Philippe Gouet
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Catabolite Repression ◽  
Tertiary Structure ◽  
Protein Hydrolysate ◽  
The Other ◽  
Similar Composition ◽  
Acid Hydrolysate ◽  
Acinetobacter Sp ◽  
Casamino Acids

The synthesis of collagenase in Acinetobacter sp. was found to be inducible by denatured collagen and by its high molecular weight fragments. The presence in the inducer of part of the tertiary structure appear to be indispensable. On the other hand, an addition of Casamino acids, meat protein hydrolysate, or a mixture of amino acids with a similar composition to gelatin does not stimulate collagenase synthesis.Enzyme production was severely repressed in the early phase of growth by glucose, arabinose, and ribose, single amino acids, proline, hydroxyproline, alanine, glutamic acid, or casein acid hydrolysate. A mechanism of repression similar to catabolite repression was involved in the phenomenon caused by carbohydrates. However, the fact that cyclic adenosine 3′5′-mono-phosphate did not overcome the repression caused by amino acids or Casamino acids, in contrast to classical catabolite repression, suggests that these two forms of repression may be distinct. [Traduit par le journal]

Preparation and analysis of mass amounts of germin: demonstration that the protein which signals the onset of growth in germinating wheat is a glycoprotein

1987 ◽  
Vol 65 (4) ◽  
pp. 354-362 ◽  
Author(s):  
Byron Lane ◽  
Zbyszko Grzelczak ◽  
Theresa Kennedy ◽  
Choy Hew ◽  
Shashikant Joshi
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Aspartic Acid ◽  
Dominant Species ◽  
Sodium Dodecyl ◽  
Amino Acid Sequences ◽  
High Yield ◽  
Wheat Embryo ◽  
Acid Hydrolysate

(1) A rapid method (2–3 weeks) is described for preparing milligram amounts of germin, in high yield, from kilogram quantities of germinated wheat embryos. An ammonium-sulphate fraction of proteins in the low-speed supernatant from an embryo homogenate is suspended in buffer for pepsin digestion, and the resulting digest is filtered through Ultrogel AcA34 to obtain germin, virtually free of contamination (<1%) by other proteins.(2) An acid hydrolysate of germin contains a full complement of the 20 different amino acids. The proportions of half-cystine, tyrosine, and tryptophan are conspicuously low (<1.5%), the proportions of aspartic acid and glycine (each ca. 11%) as well as proline (ca. 8%) are relatively high, and the cumulative proportion of hydrophobic amino acids (valine, leucine, isoleucine, phenylalanine) is also high (ca. 25%). The N-terminal sequence of germin, as determined by Edman degradation, is enriched with respect to aspartic acid, which occupies 5 of the first 15 positions.(3) There are two forms of germin, one (G) being the dominant species in the soluble fraction of homogenates of germinated embryos and the other (G′) being the dominant species in a fraction obtained by rinsing growing embryos. Consistent differences between the amino-acid compositions of G and G′ were not observed. Similarly, wherever identification was possible, the N-terminal amino-acid sequences (residues 1–22) of G and G′ were not different.(4) The polymeric and monomeric forms of germin (G or G′) give a positive Schiff reaction, characteristic of glycoproteins, when electrophoretically separated in sodium dodecyl sulphate (SDS) – poly aerylamide. Treatment with trifluoromethanesulfonic acid affirmed the glycoprotein character of germin, as did labeling, in vivo, from exogeneously supplied tritiated sugars.(5) The G and G′ forms of germin were among the most heavily labeled proteins seen in SDS–polyacrylamide separations if wheat-embryo proteins were labeled, in vivo, from exogenous supplies of tritiated mannose, glucosamine, or fucose. Differences between the patterns of glucosamine labeling and fucose labeling of G and G′ suggest the possibility that the two forms differ with respect to their carbohydrate components.

A New Buffer System for the Ion-Exchange Resin Chromatography of Amino Acids

1976 ◽  
Vol 46 (5) ◽  
pp. 372-374 ◽  
Author(s):  
V. G. Kulkarni ◽  
K. J. Whiteley
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Ion Exchange ◽  
Exchange Resin ◽  
Ion Exchange Resin ◽  
Separation Method ◽  
Buffer System ◽  
Resin Column ◽  
Acid Hydrolysate ◽  
Color Yield

A new buffer system for the ion-exchange resin chromatography of amino acids (using a Technicon Autoanalyzer) is suggested. In this system all the amino acids from the acid hydrolysate of wool are resolved satisfactorily without any loss in color yield and using only three aqueous buffers to form a gradient. No methanol is used in stock buffer preparation or during the regeneration of the resin column, so that the separation method becomes less expensive, avoids spurious absorption of methanol by resin, and prevents overlapping of certain amino acid peaks on the chromatogram.

scholarly journals Variation in Amino Acids Composition through Pre column Derivatisation using Phenylisothiocyanate by HPLC in Some Economically Important Less Explored Wild Allium Species of Western Himalayas

2020 ◽  
Vol 5 (3) ◽  
pp. 185-191
Author(s):  
H. K. Pandey ◽  
Anchala Guglani ◽  
G. C. Kharakwal ◽  
G. Balakrishna ◽  
Madhu Bala
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
High Performance ◽  
Gradient Elution ◽  
Essential Amino Acids ◽  
Western Himalayas ◽  
Allium Species ◽  
Aqueous Buffer ◽  
Acid Hydrolysate ◽  
Amino Acids Composition

Less explored Allium species are being used as green vegetables and as a condiment by the local inhabitant of high-altitude areas of Uttarakhand. In the present study, four economically important less explored wild Allium species viz. A. auriculatum, A. ampeloprasum, A. ascalonicum and A. rubellum have screened for their amino acid contents by High-performance liquid chromatography. The hydrochloric acid hydrolysate of these four species, the Allium amino acids were derivatised with phenylisothiocyanate resulting phenylthiocarbamyl derivatives and separated on a reverse-phase column by gradient elution with aqueous buffer and acetonitrile-water (60:40 v/v) and detected in UV region at 254 nm. The Pico-tag (3.9 × 300 mm) C18 column equilibrated with the solvents. The elution of all amino acid derivatives was achieved in 12 min using gradient elution by increasing concentration of aqueous buffer and acetonitrile-water. Total seventeen amino acids were present in these Allium species. The ratio of essential amino acids to total amino acids found 1:2.14 in Allium auriculatum, 1:2.35 in Allium ampeloprasum, 1:1.38 in A. ascalonicum and 1:3.44 in Allium rubellum. These less explored Allium species contained substantial amount of essential and non-essential amino acids. Among these Allium species, Allium auriculatum and Allium rubellum found most promising as far as essential and non-essential amino acids composition concerned.

scholarly journals The Amino Acid Composition of Keratins I. the Amino Acid Analysis of Merino 64?s Quality Virgin Wool

1954 ◽  
Vol 7 (1) ◽  
pp. 98 ◽  
Author(s):  
DH Simmonds
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Ion Exchange ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Amino Acid Analysis ◽  
Complete Analysis ◽  
Chromatographic Technique ◽  
Acid Hydrolysate

The ion exchange chromatographic technique of Moore and Stein (1951) has been used to estimate the amino acids in an aCid hydrolysate of merino 64's quality virgin wool. A complete analysis of one sample of this wool is summarized in Table 3 together with figures for the carbon, hydrogen, nitrogen, sulphur, and ash contents. With the exception of the glycine analyses the results confirm the figures previously accepted as reliable for wool.

THE DECOMPOSITION OF RADIOACTIVE ACETATE IN SOILS: II. THE DISTRIBUTION OF RADIOACTIVITY IN SOIL ORGANIC FRACTIONS

1964 ◽  
Vol 10 (5) ◽  
pp. 677-682 ◽  
Author(s):  
K. C. Ivarson ◽  
I. L. Stevenson
Keyword(s):  
Amino Acids ◽  
Fulvic Acid ◽  
Itaconic Acid ◽  
Alcohol Extract ◽  
Acid Hydrolysate ◽  
Considerable Portion ◽  
Organic Fractions ◽  
Humin Fraction ◽  
Hymatomelanic Acid

Soils incubated with C14-labelled acetate for 6 to 9 hours showed that 22–30% of the acetate was oxidized to CO2. Fractionation of the soil revealed that the radioactivity of the remaining substrate was widely distributed in various fractions. Greatest activity was noted in the acid hydrolyzable humin fraction (50%) with lesser amounts (5–10%) being recovered in the fulvic acid and alcohol extract. Hymatomelanic acid, α-humus, and β-humus contained only traces of activity.Ion-exchange separation of the acid hydrolysate of the humin fraction indicated that a considerable portion of the activity was associated with an unidentified compound which had certain characteristics of itaconic acid. Radioactivity was also found to be present in the 15 amino acids identified.

Homochirality as the Signature of Extra-Terrestrial Life

1997 ◽  
Vol 161 ◽  
pp. 505-510
Author(s):  
Alexandra J. MacDermott ◽  
Laurence D. Barron ◽  
Andrè Brack ◽  
Thomas Buhse ◽  
John R. Cronin ◽  
...  
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Optical Rotation ◽  
Physical Origin ◽  
Natural Choice ◽  
Rosetta Mission ◽  
Terrestrial Life ◽  
Subsurface Layers ◽  
Solar System Bodies ◽  
Origin Of Homochirality

AbstractThe most characteristic hallmark of life is its homochirality: all biomolecules are usually of one hand, e.g. on Earth life uses only L-amino acids for protein synthesis and not their D mirror images. We therefore suggest that a search for extra-terrestrial life can be approached as a Search for Extra- Terrestrial Homochirality (SETH). The natural choice for a SETH instrument is optical rotation, and we describe a novel miniaturized space polarimeter, called the SETH Cigar, which could be used to detect optical rotation as the homochiral signature of life on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. We believe that homochirality may be found in the subsurface layers on Mars as a relic of extinct life, and on other solar system bodies as a sign of advanced pre-biotic chemistry. We discuss the chiral GC-MS planned for the Roland lander of the Rosetta mission to a comet and conclude with theories of the physical origin of homochirality.

Hydrogen Cyanide Polymers from the Impact of Comet P/Shoemaker-Levy 9 on Jupiter

1997 ◽  
Vol 161 ◽  
pp. 179-187
Author(s):  
Clifford N. Matthews ◽  
Rose A. Pesce-Rodriguez ◽  
Shirley A. Liebman
Keyword(s):  
Amino Acids ◽  
Solar System ◽  
Hydrogen Cyanide ◽  
Nitrogen Heterocycles ◽  
Laboratory Studies ◽  
Heterogeneous Solids ◽  
The Many ◽  
Comet Halley ◽  
The Impact ◽  
By Products

AbstractHydrogen cyanide polymers – heterogeneous solids ranging in color from yellow to orange to brown to black – may be among the organic macromolecules most readily formed within the Solar System. The non-volatile black crust of comet Halley, for example, as well as the extensive orangebrown streaks in the atmosphere of Jupiter, might consist largely of such polymers synthesized from HCN formed by photolysis of methane and ammonia, the color observed depending on the concentration of HCN involved. Laboratory studies of these ubiquitous compounds point to the presence of polyamidine structures synthesized directly from hydrogen cyanide. These would be converted by water to polypeptides which can be further hydrolyzed to α-amino acids. Black polymers and multimers with conjugated ladder structures derived from HCN could also be formed and might well be the source of the many nitrogen heterocycles, adenine included, observed after pyrolysis. The dark brown color arising from the impacts of comet P/Shoemaker-Levy 9 on Jupiter might therefore be mainly caused by the presence of HCN polymers, whether originally present, deposited by the impactor or synthesized directly from HCN. Spectroscopic detection of these predicted macromolecules and their hydrolytic and pyrolytic by-products would strengthen significantly the hypothesis that cyanide polymerization is a preferred pathway for prebiotic and extraterrestrial chemistry.

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