scholarly journals The isolation of some hitherto undescribed products of hydrolysis of proteins. —Part II

1926 ◽  
Vol 99 (699) ◽  
pp. 476-487 ◽  
Keyword(s):  
Amino Acids ◽  
Cold Water ◽  
Hydrolysis Products ◽  
First Time ◽  
Further Development ◽  
Hydrolysis Of

The main object of the investigations described in this paper was the further development of the “carbamate process” for the separation of the hydrolysis products of proteins, already described by the authors, and applied to the separation of the hydrolysis products of gelatin by Miss H. L. Kingston and Schryver. It has been shown that, by this method, the hydrolysis products can be fractionated into the following main groups:— I. Those products yielding barium salts insoluble in 70 per cent, alcohol; they consist entirely of dicarboxylic amino-acids. II. Those products yielding barium carbamates insoluble in ice-cold water. Two products only have, up to the present, been found in this fraction, viz., glycine, and a base, hydroxylysine, isolated for the first time by the authors in conjunction with Dr. D. H. Mukherjee.

scholarly journals The isolation of a product of hydrolysis of the proteins hitherto undescribed

1925 ◽  
Vol 98 (687) ◽  
pp. 58-65 ◽  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acid ◽  
Convenient Method ◽  
Free Amino ◽  
Barium Carbonate ◽  
Present Communication ◽  
Hydrolysis Products ◽  
Hydrolysis Of

Some time ago, two of the authors of the present communication, in seeking a method for the separation of the amino-acids from the carbohydrates, found that under certain conditions the former could be readily separated in the form of the barium salts of their carbamates, a class of compounds originally described by Siegfried. As these carbamates, on heating with water, are readily decomposed into barium carbonate and the free amino-acid, it was suggested that a convenient method might be evolved, using the formation of these compounds as a basis, for the separation of the hydrolysis products of the proteins.* This suggestion was followed up, and a method was subsequently elaborated and applied to the separation of the hydrolysis products of gelatin by one of the authors in conjunction with Miss H. L. Kingston. Since the publication of the two papers just quoted, the researches on the use of the “carbamate method,” as it may be conveniently called, have been continued, and promise results, which may ultimately lead to a satisfactory separation of most of the hydrolysis products of the proteins when only relatively small amounts of material are available for investigation. During the course of this work the base, which is the chief subject discussed in this paper, was discovered.

scholarly journals ANALYSIS OF FLAVONES C-GLYCOSIDES AND AND STEPWISE HYDROLYSIS OF THEIR ACETATES IN THE LEAVES OF RUBUS CHAMAEMORUS L.

2021 ◽  
pp. 257-265
Author(s):  
Andrey Kennet Whaley ◽  
Anastasiya Olegovna Ponkratova ◽  
Anastasiya Andreyevna Orlova ◽  
Evgeni Borisovich Serebryakov ◽  
Stanislav Ivanovich Selivanov ◽  
...  
Keyword(s):  
Biological Activity ◽  
Hplc Analysis ◽  
Higher Plants ◽  
Two Dimensional ◽  
Cardiotonic Activity ◽  
Hydrolysis Products ◽  
Rubus Chamaemorus ◽  
Growing Conditions ◽  
First Time ◽  
Hydrolysis Of

The C-glycoside embinin and its mono- and diacetate derivatives have immunotropic and cardiotonic activity, which makes the search for plants that contain them interesting. Embinin and its acetate derivatives were previously isolated only from some plants of the genus Iris, the habitat and growing conditions of which are very different from those of the genus Rubus. As a result of the study, the structure of seven C-glycosides, embinin derivatives, isolated from the leaves of Rubus chamaemorus L. (Rosaceae) was established. Using HR-ESI-MS, HPLC-MS, as well as one- and two-dimensional NMR spectroscopy, the structure of three substances isolated in individual form was established: embinin (1) and its diacetyl derivatives – 2''',3'''-diacetylembinin (5) and 3''',4'''-diacetylembinin (7). The method of stepwise hydrolysis of C-glycoside acetate residues proposed in this study, followed by HPLC analysis of the resulting hydrolysis products, made it possible to establish the structure of minor flavone C-glycosides contained in the leaves of Rubus chamaemorus L.: 2'''-acetylembinin (2), 3'''-acetylembinin (3), 4'''-acetylembinin (4) and 2''',4'''-diacetylembinin (6). All these compounds were found in the leaves of Rubus chamaemorus L. for the first time. The C-glycosides - embinin and its acetate derivatives are rare metabolites of higher plants, the presence of which is determined by the peculiarity of their physiology, and the biological activity determines the prospects for medical use.

SYNTHESIS OF AMINO ACIDS FROM SUBSTITUTED CYANOACETIC ESTERS

1948 ◽  
Vol 26b (7) ◽  
pp. 503-510 ◽  
Author(s):  
Paul E. Gagnon ◽  
Jean L. Boivin
Keyword(s):  
Amino Acids ◽  
Carboxylic Acid ◽  
Hydrochloric Acid ◽  
Aminobutyric Acid ◽  
Acid Hydrochloride ◽  
First Time ◽  
Hydrolysis Of

Nine α-amino acids, namely, dl-alanine, dl-α-aminobutyric acid, dl-α-ammoenanthic acid, dl-α-amino-γ-phenoxybutyric acid, dl-C-phenylglycine, dl-proline, dl-ornithine, dl-lysine and 2-aminoindane-2-carboxylic acid have been prepared from α-substituted cyanoacetic esters. Pyrrolidine or piperidine was isolated when it was attempted to prepare ornithine or lysine by hydrolysis of diurethanes with hydrochloric acid. When a mixture of formic and hydrochloric acids and water was used as hydrolyzing agent, ornithine or lysine was obtained in low yield in addition to traces of pyrrolidine or piperidine. The following compounds, as far as the authors are aware, have been prepared for the first time: α-cyanopropionhydrazide, benzal α-cyanopropionhydrazide, α-cyanopropionic azide, α-carbethoxyaminopropiononitrile, α-cyanobutyrhydrazide, benzal α-cyanobutyrhydrazide, α-cyanobutyric azide, α-carbethoxyaminobutyronitrile, ethyl α-cyanoenanthate, α-cyanoenanthic hydrazide, benzal α-cyanoenanthic hydrazide, α-cyanoenanthic azide, α-carbethoxyaminoenanthonitrile, 5-(n-amyl)-hydantoin, ethyl α-cyano-γ-phenoxybutyrate, ethyl bis-β-phenoxyethylmalonate mononitrile, α-cyano-γ-phenoxybutyrhydrazide, benzal α-cyano-γ-phenoxybutyrhydrazide, α-cyano-γ-phenoxybutyric azide, α-carbethoxyamino-γ-phenoxybutyronitrile, 5-(β-phenoxyethyl)-hydantoin, α-cyano-α-phenylacethydrazide, benzal α-cyano-α-phenylacethydrazide, α-cyano-α-phenylacetic azide, ethyl δ-bromo-α-cyanovalerate, δ-bromo-α-cyanovalerhydrazide, benzal δ-bromo-α-cyanovalerhydrazide, δ-bromo-α-cyanovaleric azide, δ-bromo-α-carbethoxyaminovaleronitrile, dibenzal α-cyanoadipic dihydrazide, α-cyanoadipic diazide, α,δ-dicarbethoxyaminoadiponitrile, dibenzal α-cyanopimelic dihydrazide, α-cyanopimelic diazide, α, ε-dicarbethoxyaminocapronitrile, 2-cyano-2-carbethoxyindane, 2-cyano-2-carboxylindane hydrazide, benzal 2-cyano-2-carboxylindane hydrazide, 2-cyano-2-carboxylindane azide, 2-cyano-2-carbethoxyaminoindane, 2-aminoindane-2-carboxylic acid, 2-aminoindane-2-carboxylic acid hydrochloride.

Nucleic Acid Related Compounds. 14. 3′-O-Aminoacyl-2′-O-methyladenosines and 2′-O-Aminoacyl-3′-O-methyladenosines Related to Charged tRNA Termini

1974 ◽  
Vol 52 (22) ◽  
pp. 3803-3813 ◽  
Author(s):  
Morris J. Robins ◽  
Malcolm MacCoss ◽  
G. Ramani
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Nucleic Acid ◽  
Protein Biosynthesis ◽  
Glycosidic Bonds ◽  
Acid Anhydrides ◽  
High Yields ◽  
First Time ◽  
Hydrolysis Of ◽  
Related Compounds

Aminoacyl nucleosides derived from 2′-O-methyladenosine and 3′-O-methyladenosine have been isolated as pure solids and completely characterized for the first time. Coupling of 5′-O-(mono-p-methoxytrityl)-2′-O-methyl- (and 3′-O-methyl-) adenosines (1 and 6, respectively) with N-tert-butyloxycarbonyl(N-tBOC)-amino acid anhydrides (2a–c) (generated insitu from the corresponding N-tBOC-amino acids and N,N′-dicyclohexylcarbodiimide) in the presence of 4-N,N-dimethylaminopyridine gave the 3′-O-(N-tBOC-aminoacyl)-5′-O-(mono-p-methoxytrityl-2′-O-methyladenosines (3a–c) and 2′-O-(N-tBOC-aminoacyl)-5′-O-(mono-p-methoxytrityl-3′-O-methyladenosines (7a–c), respectively, in good yields. The L-leucine (a), L-phenylalanine (b), and L-methionine (c) compounds were prepared in each series. Complete deblocking was effected using 98% formic acid since usual procedures had disadvantages with these molecules. The 3′-O-(L-aminoacyl)-2′-O-methyladenosines (4a–c) and 2′-O-(L-aminoacyl)-3′-O-methyladenosines (8a–c) were obtained in high yields with no detectable hydrolysis of the aminoacyl or glycosidic bonds under these conditions.N-Formylmethionyl and N-acetylphenylalanyl derivatives were prepared in each series by acylation of the deblocked products with acetic formic anhydride and p-nitrophenyl acetate, respectively. Biochemical rationale for the use of these compounds in the study of protein biosynthesis and initiation processes are discussed. The puromycin-like activity of 3′-O-phenylalanyl-2′-O-methyl-adenosine (4b) was confirmed.

Deinking of recycled paper by coupling of the enzyme endo-β-1,4-D-glucanasa and the cellulose, and by using a laboratory flotation column

MRS Advances ◽  
2020 ◽  
Vol 5 (52-53) ◽  
pp. 2669-2678
Author(s):  
Jeovani González P. ◽  
Ramiro Escudero G
Keyword(s):  
Amino Acids ◽  
Sodium Hydroxide ◽  
Paper Industry ◽  
Computational Simulation ◽  
Cellulose Fibers ◽  
Residual Water ◽  
Chemical Reagent ◽  
Recycled Paper ◽  
Flotation Column ◽  
Hydrolysis Of

AbstractDeinking of recycled office (MOW) paper was carried out by using a flotation column and adding separately sodium hydroxide, and the enzyme Cellulase Thricodema Sp., as defibrillators.The de-inked cellulose fibers were characterized according to the standards of the paper industry, to compare the efficiency of the deinking of each chemical reagent used to hydrolyze the fibers and defibrillate them.The computational simulation of the molecular coupling between the enzyme and cellulose was performed, to establish the enzyme-cellulose molecular complex and then to identify the principal amino-acids of endo-β-1,4-D-glucanase in this molecular link, which are responsible for the hydrolysis of the cellulose.Experimental results show the feasibility to replace sodium hydroxide with the enzyme Cellulase Thricodema Sp., by obtaining deinked cellulose with similar optical and physical properties.The use of the enzyme instead of sodium hydroxide avoids the contamination of the residual water; in addition to that, the column is operated more easily, taking into consideration that the pH of the system goes from alkaline to neutral.

Single Amino Acid Based Self-Assemblies of Cysteine and Methionine

2018 ◽  
Author(s):  
Nidhi Gour ◽  
Bharti Koshti ◽  
Chandra Kanth P. ◽  
Dhruvi Shah ◽  
Vivek Shinh Kshatriya ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Self Assembly ◽  
Aromatic Amino Acids ◽  
Neutral Condition ◽  
Single Amino Acid ◽  
Binding Assays ◽  
Human Neuroblastoma ◽  
Cytotoxicity Assays ◽  
First Time

We report for the very first time self-assembly of Cysteine and Methionine to discrenible strucutres under neutral condition. To get insights into the structure formation, thioflavin T and Congo red binding assays were done which revealed that aggregates may not have amyloid like characteristics. The nature of interactions which lead to such self-assemblies was purported by coincubating assemblies in urea and mercaptoethanol. Further interaction of aggregates with short amyloidogenic dipeptide diphenylalanine (FF) was assessed. While cysteine aggregates completely disrupted FF fibres, methionine albeit triggered fibrillation. The cytotoxicity assays of cysteine and methionine structures were performed on Human Neuroblastoma IMR-32 cells which suggested that aggregates are not cytotoxic in nature and thus, may not have amyloid like etiology. The results presented in the manuscript are striking, since to the best of our knowledge,this is the first report which demonstrates that even non-aromatic amino acids (cysteine and methionine) can undergo spontaneous self-assembly to form ordered aggregates.

Studies on Chromatographic Fractioning by Cations Exchangers of a Bovine Hemoglobin Hydrolysate

2018 ◽  
Vol 69 (10) ◽  
pp. 2794-2798
Author(s):  
Alina Diana Panainte ◽  
Ionela Daniela Morariu ◽  
Nela Bibire ◽  
Madalina Vieriu ◽  
Gladiola Tantaru ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Amino Acids ◽  
Retention Time ◽  
Chromatographic Separation ◽  
Bovine Hemoglobin ◽  
Reverse Phase ◽  
Hplc System ◽  
Fast Flow ◽  
Hydrolysis Of ◽  
Phase Column

A peptidic hydrolysate has been obtained through hydrolysis of bovine hemoglobin using pepsin. The fractioning of the hydrolysate was performed on a column packed with CM-Sepharose Fast Flow. The hydrolysate and each fraction was filtered and then injected into a HPLC system equipped with a Vydak C4 reverse phase column (0.46 x 25 cm), suitable for the chromatographic separation of large peptides with 20 to 30 amino acids. The detection was done using mass spectrometry, and the retention time, size and distribution of the peptides were determined.

scholarly journals Autophagy Deficiency by Atg4B Loss Leads to Metabolomic Alterations in Mice

Metabolites ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 481
Author(s):  
Gemma G. Martínez-García ◽  
Raúl F. Pérez ◽  
Álvaro F. Fernández ◽  
Sylvere Durand ◽  
Guido Kroemer ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Amino Acids ◽  
Mammalian Cells ◽  
Tissue Homeostasis ◽  
In Vivo Studies ◽  
Protective Mechanism ◽  
Cardiac Damage ◽  
Wide Range ◽  
First Time

Autophagy is an essential protective mechanism that allows mammalian cells to cope with a variety of stressors and contributes to maintaining cellular and tissue homeostasis. Due to these crucial roles and also to the fact that autophagy malfunction has been described in a wide range of pathologies, an increasing number of in vivo studies involving animal models targeting autophagy genes have been developed. In mammals, total autophagy inactivation is lethal, and constitutive knockout models lacking effectors of this route are not viable, which has hindered so far the analysis of the consequences of a systemic autophagy decline. Here, we take advantage of atg4b−/− mice, an autophagy-deficient model with only partial disruption of the process, to assess the effects of systemic reduction of autophagy on the metabolome. We describe for the first time the metabolic footprint of systemic autophagy decline, showing that impaired autophagy results in highly tissue-dependent alterations that are more accentuated in the skeletal muscle and plasma. These changes, which include changes in the levels of amino-acids, lipids, or nucleosides, sometimes resemble those that are frequently described in conditions like aging, obesity, or cardiac damage. We also discuss different hypotheses on how impaired autophagy may affect the metabolism of several tissues in mammals.

Access to 2-Arylquinazolines via Catabolism/Reconstruction of Amino Acids with Insertion of Dimethyl Sulfoxide

2021 ◽  
Author(s):  
Jin-Tian Ma ◽  
Li-Sheng Wang ◽  
Zhi Chai ◽  
Xin-Feng Chen ◽  
Bo-Cheng Tang ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Dimethyl Sulfoxide ◽  
Nitrogen Source ◽  
Carbon And Nitrogen ◽  
First Time

Quinazoline skeletons are synthesized by amino acids catabolism/reconstruction combined with dimethyl sulfoxide insertion/cyclization for the first time. The amino acid acts as a carbon and nitrogen source through HI-mediated catabolism...

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