Artificial Polymers made of α-amino Acids - Poly(Amino Acid)s, Pseudo-Poly(Amino Acid)s, Poly(Depsipeptide)s, and Pseudo-Proteins

2020 ◽  
Vol 26 (5) ◽  
pp. 566-593 ◽  
Author(s):  
Nino Zavradashvili ◽  
Jordi Puiggali ◽  
Ramaz Katsarava
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Disease Transmission ◽  
Degradable Polymers ◽  
Molecular Architecture ◽  
Peptide Bonds ◽  
Green Materials ◽  
Degradable Biomaterials ◽  
Risk Of Disease ◽  
Macromolecular Architecture

Degradable polymers (DPs) - “green materials” of the future, have an innumerable use in biomedicine, particularly in the fields of tissue engineering and drug delivery. Among these kind of materials naturally occurring polymers - proteins which constituted one of the most important “bricks of life” - α-amino acids (AAs) are highly suitable. A wide biomedical applicability of proteins is due to special properties such as a high affinity with tissues and releasing AAs upon biodegradation that means a nutritive potential for cells. Along with these positive characteristics proteins as biomedical materials they have some shortcomings, such as batch-to-batch variation, risk of disease transmission, and immune rejection. The last limitation is connected with the molecular architecture of proteins. Furthermore, the content of only peptide bonds in protein molecules significantly restricts their material properties. Artificial polymers with the composition of AAs are by far more promising as degradable biomaterials since they are free from the limitations of proteins retaining at the same time their positive features - a high tissue compatibility and nutritive potential. The present review deals with a brief description of different families of AA-based artificial polymers, such as poly(amino acid)s, pseudo-poly(amino acid)s, polydepsipeptides, and pseudo-proteins - relatively new and broad family of artificial AA-based DPs. Most of these polymers have a different macromolecular architecture than proteins and contain various types of chemical links along with NH-CO bonds that substantially expands properties of materials destined for sophisticated biomedical applications.

Comparison of some properties of soil humic acids and synthetic phenolic polymers incorporating amino derivaties

Soil Research ◽  
1966 ◽  
Vol 4 (1) ◽  
pp. 41 ◽  
Author(s):  
JN Ladd ◽  
JHA Butler
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Acid Hydrolysis ◽  
Humic Acids ◽  
Gel Filtration ◽  
Quinone Imine ◽  
Peptide Bonds ◽  
Molecular Weights ◽  
Soil Humic Acids ◽  
Properties Of Soil

Twenty-three model phenolic polymers, either nitrogen-free or incorporating amino acids, peptides, or proteins, have been prepared from p-benzoquinone and catechol under mild oxidative conditions. Two lines of experimentation have demonstrated properties of soil humic acids closely similar to those of polymers incorporating proteins, but different from those of polymers incorporating amino acids: (1) fractionation of humic acids and synthetic polymers by 'Sephadex' gel filtration showed that the percentage of components of molecular weights nominally greater than 100 000 ranged from 52-76 % for eight humic acids tested, 53-59 % for benzoquinone-protein polymers (excluding polymers containing protamine), but less than 20% for all other polymers; (2) acid hydrolysis with 6M HCl resulted in a partial release of polymer nitrogen. Amino acid nitrogen in the hydrolysates accounted for 32.4-51.9 % of humic acid nitrogen, 31.2-56.3 % of the nitrogen of polymers incorporating protein, but less than 10.8% of the nitrogen of polymers incorporating individual amino acids. Experiments with model monomeric N-phenylglycine derivatives and with polymers incorporating simple peptides showed that the bond between the carbon atom of an aromatic ring and the nitrogen atom of an a-amino acid is far more stable to acid hydrolysis than peptide bonds or bonds linking amino acids in humic acids. Glycine is, however, readily released from N-phenylglycine derivatives when conditions favour their oxidation to a quinone-imine intermediate. Incorporation of proteins into phenolic polymers prevented the detection of peptide bonds by the Folin reagent.

Amino Acids and the Asymmetry of Life

2013 ◽  
Vol 21 (2) ◽  
pp. 190-199 ◽  
Author(s):  
Uwe J. Meierhenrich
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Building Blocks ◽  
Space Mission ◽  
Mirror Image ◽  
Recent Experimental Data ◽  
Molecular Architecture ◽  
Amino Acid Enantiomers ◽  
Left Handed ◽  
Life On Earth

‘How did life start on Earth?’ and ‘Why were left-handed amino acids selected for the architecture of proteins?’ A new attempt to answer these questions of high public and interdisciplinary scientific interest will be provided by this review. It will describe most recent experimental data on how the basic and molecular building blocks of life, amino acids, formed in a prebiotic setting. Most amino acids are chiral, that is that they cannot be superimposed with their mirror image molecules (enantiomers). In processes triggering the origin of life on Earth, the equal occurrence, i.e. the parity between left-handed amino acids and their right-handed mirror images, was violated. In the case of amino acids, the balance was tipped to the left – as a result of which life's proteins today exclusively implement the left-handed form of amino acids, called l-amino acid enantiomers. Neither plants, nor animals, including humans, make use of d-amino acids for the molecular architecture of their proteins (enzymes). This review addresses the molecular asymmetry of amino acids in living organisms, namely the preference for left-handedness. What was the cause for the violation of molecular parity of amino acids in the emergence of life on Earth? All the fascinating models proposed by physicists, chemists, and biologists will be vividly presented including the scientific conflicts. Special emphasis will be given to amino acid enantiomers that were subjected to chiral photons. The interaction between racemic molecules and chiral photons was shown to produce an enantiomeric enrichment that will be discussed in the context of absolute asymmetric synthesis. The concluding paragraphs will describe the attempt to verify any of those models with the chirality-module of the Rosetta mission. This European space mission contains probe Philae that was launched on board the Rosetta spacecraft with the aim of landing on the icy surface of comet 67P/Churyumov-Gerasimenko and analysing whether chiral organic compounds are present that could have been brought to the Earth by comet impacts.

scholarly journals Qualitative Protein Hydrolyzed from Nerita undata in supralittoral rocks and mezolittoral zone of Hasa Cape using TLC

2021 ◽  
Vol 9 (2) ◽  
pp. 118-123
Author(s):  
Healthy Kainama ◽  
Hanoch J. Sohilait ◽  
Christian Jacob Souisa
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Essential Amino Acids ◽  
Coastal Communities ◽  
High Quality ◽  
Peptide Bonds ◽  
High Quality Protein ◽  
Kjeldahl Method ◽  
Acetic Acid Water ◽  
Layer Chromatography

Gastropods are the sources of protein for coastal communities in the Maluku islands. We conducted analysis quantitative and qualitative of protein in Nerita undata meat from Hasa Cape in Saparua Island. The percentage of protein was analyzed by the Kjeldahl method. Qualitative analysis began with breaking peptide bonds in protein to amino acid components by sulphuric acid and barium hydroxide hydrolyzed. We identified amino acid compounds by using thin-layer chromatography (TLC) in butanol-acetic acid-water (8:1:1, v/v) as eluent. The result showed that N. undata meat contains 11.15% of protein and twelve amino acid compounds. There are seven essential amino acids in N. undata meat from supralittoral rocks and mezolittoral zone of Hasa cape is a source of quality protein. Thus, this species can be considered as a source of high-quality protein.

scholarly journals Structural features that make oligopeptides susceptible substrates for hydrolysis by recombinant thimet oligopeptidase

1997 ◽  
Vol 324 (2) ◽  
pp. 517-522 ◽  
Author(s):  
Antonio. C. M CAMARGO ◽  
Marcelo. D GOMES ◽  
Antonia. P REICHL ◽  
Emer. S FERRO ◽  
Saul JACCHIERI ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Cleavage Site ◽  
Catalytic Efficiency ◽  
Structural Features ◽  
Amino Acid Residues ◽  
Systematic Analysis ◽  
Peptide Bonds ◽  
C Terminus ◽  
Thimet Oligopeptidase

A systematic analysis of the peptide sequences and lengths of several homologues of bioactive peptides and of a number of quenched-fluorescence (qf) opioid- and bradykinin-related peptides was performed to determine the main features leading the oligopeptides to hydrolysis by the recombinant rat testis thimet oligopeptidase (EC 3.4.24.15). The results indicate that a minimum substrate length of six amino acids is required and that among the oligopeptides six to thirteen amino acid residues long, their susceptibility as substrates is highly variable. Thimet oligopeptidase was able to hydrolyse, with similar catalytic efficiency, peptide bonds having hydrophobic or hydrophilic amino acids as well as proline in the P1 position of peptides, ranging from a minimum of six to a maximum of approximately thirteen amino acid residues. An intriguing observation was the shift of the cleavage site, at a Leu-Arg bond in qf dynorphin-(2–8) [qf-Dyn2–8; Abz-GGFLRRV-EDDnp, where Abz stands for o-aminobenzoyl and EDDnp for N-(2,4-dinitrophenyl) ethylenediamine], to Arg-Arg in qf-Dyn2–8Q, in which Gln was substituted for Val at its C-terminus. Similarly, a cleavage site displacement was also observed with the hydrolysis of the internally quenched-fluorescence bradykinin analogues containing Gln at the C-terminal position, namely Abz-RPPGFSPFR-EDDnp and Abz-GFSPFR-EDDnp are cleaved at the Phe-Ser bond, but Abz-RPPGFSPFRQ-EDDnp and Abz-GFSPFRQ-EDDnp are cleaved at the Pro-Phe bond.

scholarly journals Synthesis, extraction and idetification of meat bioactive peptides: a review

2021 ◽  
Vol 888 (1) ◽  
pp. 012058
Author(s):  
Edy Susanto ◽  
Anik Fadlilah ◽  
Muhammad Fathul Amin
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Functional Food ◽  
Bioactive Peptides ◽  
Peptide Identification ◽  
Bioactive Peptide ◽  
Covalent Bonds ◽  
Peptide Bonds ◽  
Body Location ◽  
Potential Use

Abstract The consumption of meat should consider the concept of functional food. The meat had a highquality protein and contain of bioactive peptide compounds. Amino acid was component of bioactive peptides compound. It joined by covalent bonds known as amide or peptide bonds. A lot of research was currently focused on the bioactive peptide compounds isolated from myofibril and sarcoplasmic proteins with the synthesis, extraction, and identification methods. This study used a systematic review to get the structure of amino acids that the source of bioactive components and the principle of synthesis, extraction and identification of bioactive peptide in the meat. This paper highlights were finding on the structure of amino acid in the meat. The proportion of amino acids was also different in each animal body location. The result identified that more than 170 peptides were released from the main structure of the myofibril (actin, myosin) and sarcoplasmic muscle proteins, and the synthesis, extraction and bioactive peptide identification in the meat as well as their potential use as functional food.

scholarly journals Study of the influence of neighboring amino acids on proline conformation

2016 ◽  
Vol 5 (6) ◽  
pp. 627-631
Author(s):  
Jose Elias Cancino Herrera ◽  
Salvador Noriega ◽  
Shehret Tilvaldyev ◽  
Alfredo Villanueva Montellano ◽  
Alejandra Flores Ortega
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Dft Calculations ◽  
Energy Minimum ◽  
Conformational Preference ◽  
Peptide Bonds ◽  
The Third ◽  
Conformational Preferences ◽  
Two Systems

DFT calculations made at the B3LYP/6-31+G(d) level were used to investigate how the incorporation of a second amino acid into the backbone affects the conformational preferences of proline. Specifically, the this research studied the second amino acids L-proline and L-alanine and the trans isomerism of the peptide bonds. The lowest energy minimum has been found to have a different conformation for the two systems investigated; while the third presents a different conformation. The results obtained offer evidence of the influence of these systems on the conformational preference of proline.

scholarly journals Vibration assisted electron tunneling through nano-gaps in graphene nano-ribbons for amino-acid and peptide bond recognition

2019 ◽  
Vol 1 (9) ◽  
pp. 3547-3554 ◽  
Author(s):  
Giuseppe Zollo ◽  
Aldo Eugenio Rossini
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Electron Tunneling ◽  
Graphene Nanoribbons ◽  
Peptide Bond ◽  
Vibrational Modes ◽  
Peptide Bonds ◽  
Assisted Tunneling

Vibrational modes assisted tunneling in nano-gaps of graphene nanoribbons reveal specific features allowing the recognition of amino-acids and peptide bonds with atomistic resolution.

scholarly journals Kinetics and Substrate Specificity of Membrane-Reconstituted Peptide Transporter DtpT ofLactococcus lactis

2000 ◽  
Vol 182 (9) ◽  
pp. 2530-2535 ◽  
Author(s):  
Gang Fang ◽  
Wil N. Konings ◽  
Bert Poolman
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Substrate Specificity ◽  
Free Amino ◽  
Peptide Transport ◽  
Peptide Transporter ◽  
Amino Acid Residues ◽  
Peptide Bonds ◽  
Carboxyl Terminal ◽  
Affinity Interaction

ABSTRACT The peptide transport protein DtpT of Lactococcus lactis was purified and reconstituted into detergent-destabilized liposomes. The kinetics and substrate specificity of the transporter in the proteoliposomal system were determined, using Pro-[14C]Ala as a reporter peptide in the presence of various peptides or peptide mimetics. The DtpT protein appears to be specific for di- and tripeptides, with the highest affinities for peptides with at least one hydrophobic residue. The effect of the hydrophobicity, size, or charge of the amino acid was different for the amino- and carboxyl-terminal positions of dipeptides. Free amino acids, ω-amino fatty acid compounds, or peptides with more than three amino acid residues do not interact with DtpT. For high-affinity interaction with DtpT, the peptides need to have free amino and carboxyl termini, amino acids in the l configuration, andtrans-peptide bonds. Comparison of the specificity of DtpT with that of the eukaryotic homologues PepT1 and PepT2 shows that the bacterial transporter is more restrictive in its substrate recognition.

ISARIIN, A NEW DEPSIPEPTIDE FROM ISARIA CRETACEA

1962 ◽  
Vol 40 (8) ◽  
pp. 1579-1584 ◽  
Author(s):  
L. C. Vining ◽  
W. A. Taber
Keyword(s):  
Amino Acids ◽  
Quantitative Analysis ◽  
Amino Acid ◽  
Molar Ratio ◽  
Cyclic Structure ◽  
Terminal Amino Acid ◽  
Peptide Bonds ◽  
Metabolic Products ◽  
Ester Linkage ◽  
Terminal Amino

One of the metabolic products of the fungus Isaria cretacea has been found to yield four different amino acids and a hydroxyacid on acid hydrolysis. The amino acids were identified as glycine, L-alanine, L-valine, and D-leucine, and a quantitative analysis showed them to be present in the molar ratio of 1:1:2:1, respectively. The hydroxyacid was identified as D-β-hydroxydodecanoic acid. These units appear to be combined in a simple cyclic structure by means of peptide bonds and an ester linkage between the hydroxyl of hydroxydecanoic acid and the carboxyl of the C-terminal amino acid. The sequence valine → β-hydroxydodecanoic acid → glycine has been established.

Dietary intake of tryptophan tied emotion-related impulsivity in humans

2019 ◽  
pp. 1-8 ◽  
Author(s):  
Florian Javelle ◽  
Descartes Li ◽  
Philipp Zimmer ◽  
Sheri L. Johnson
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Food Intake ◽  
Essential Amino Acid ◽  
Food Habits ◽  
Psychological Disorder ◽  
Serotonin Synthesis ◽  
Amino Acid Tryptophan ◽  
Pass Through ◽  
Three Factor

Abstract. Emotion-related impulsivity, defined as the tendency to say or do things that one later regret during periods of heightened emotion, has been tied to a broad range of psychopathologies. Previous work has suggested that emotion-related impulsivity is tied to an impaired function of the serotonergic system. Central serotonin synthesis relies on the intake of the essential amino acid, tryptophan and its ability to pass through the blood brain barrier. Objective: The aim of this study was to determine the association between emotion-related impulsivity and tryptophan intake. Methods: Undergraduate participants (N = 25, 16 women, 9 men) completed a self-rated measure of impulsivity (Three Factor Impulsivity Index, TFI) and daily logs of their food intake and exercise. These data were coded using the software NutriNote to evaluate intakes of tryptophan, large neutral amino acids, vitamins B6/B12, and exercise. Results: Correlational analyses indicated that higher tryptophan intake was associated with significantly lower scores on two out of three subscales of the TFI, Pervasive Influence of Feelings scores r =  –.502, p < . 010, and (lack-of) Follow-Through scores, r =  –.407, p < . 050. Conclusion: Findings provide further evidence that emotion-related impulsivity is correlated to serotonergic indices, even when considering only food habits. It also suggests the need for more research on whether tryptophan supplements might be beneficial for impulsive persons suffering from a psychological disorder.

Sign in / Sign up

Export Citation Format

Share Document