Amino acids. Medical search. FAQ

sulfur amino
Additionally, decreased sulfur amino acid intake is known to cause oxidative stress. (mdpi.com)
Studies were designed to test whether oxidative stress in fructose-sweetened liquid-induced fatty liver is caused by decreased ad libitum solid food intake with associated inadequate sulfur amino acid intake. (mdpi.com)
C57BL6 mice were grouped as: control ( ad libitum water), fructose ( ad libitum 30% fructose-sweetened liquid), glucose ( ad libitum 30% glucose-sweetened water) and pair-fed ( ad libitum water and sulfur amino acid intake same as the fructose group). (mdpi.com)
however, inadequate sulfur amino acid intake was not the cause of this oxidative stress. (mdpi.com)
One-hundred twenty individually fed steer calves were used to evaluate feather meal as a source of sulfur amino acids. (unl.edu)
These results indicate feather meal can provide a portion of the sulfur amino acids lacking in meat and bone meal. (unl.edu)

different amino acids
Importantly, you can also find milligram amounts for 18 different amino acids in all 100 of our food profiles by clicking on the in-depth nutritional profile link toward the end of each food profile. (whfoods.org)
There are 20 different amino acids that combine to create the impressive array of chemical versatility of proteins. (news-medical.net)
A list of the different amino acids, their benefits and their food sources. (calameo.com)
Thus, the ribosome will not be able to discriminate between tRNAs with the same anticodon but linked to different amino acids. (wikipedia.org)
Amino acids can also be classified according to how many different amino acids they can be exchanged by through single nucleotide substitution. (wikipedia.org)

standard amino acids
Twenty of the proteinogenic amino acids are encoded directly by triplet codons in the genetic code and are known as "standard" amino acids. (wikipedia.org)
The genetic code encodes 20 standard amino acids for incorporation into proteins during translation. (wikipedia.org)
These non-standard amino acids do not have a dedicated codon, but are added in place of a stop codon when a specific sequence is present, UGA codon and SECIS element for selenocysteine, UAG PYLIS downstream sequence for pyrrolysine. (wikipedia.org)
This amino acid is formed by joining to the ε-amino group of lysine a carboxylated pyrroline ring There are various groups of amino acids: 20 standard amino acids 22 proteinogenic amino acids over 80 amino acids created abiotically in high concentrations about 900 are produced by natural pathways over 118 engineered amino acids have been placed into protein These groups overlap, but are not identical. (wikipedia.org)
Examples include: Among 20 standard amino acids: Phenylalanine Tryptophan Tyrosine Histidine Others: Thyroxine 5-Hydroxytryptophan L-DOPA Phenylalanine → Tyrosine → L-DOPA → (Dopamine) → (Epinephrine) → (Norepinephrine) Tryptophan → 5-hydroxytryptophan → (Serotonin) Phenylalanine → Tyrosine → Thyroxine Phenylalanine, tryptophan, and histidine are essential amino acids for animals. (wikipedia.org)
Ketogenic amino acid List of standard amino acids Glycolysis Metabolism Brosnan J (1 June 2003). (wikipedia.org)
Humans are an excellent example of this, since humans can only synthesize 11 of the 20 standard amino acids (a.k.a. non-essential amino acid), and in time of accelerated growth, histidine, can be considered an essential amino acid. (wikipedia.org)

aromatic
Here, we show how interference with CYP enzymes acts synergistically with disruption of the biosynthesis of aromatic amino acids by gut bacteria, as well as impairment in serum sulfate transport. (mdpi.com)
However, you will find recommended food sources for different types of amino acids (including branched chain, sulfur-containing, aromatic, and others) in the Summary of Food Sources section of this article. (whfoods.org)
Lastly, BCAAs share the same transport protein into the brain with aromatic amino acids (Trp, Tyr, and Phe). (wikipedia.org)
An aromatic amino acid (AAA) is an amino acid that includes an aromatic ring. (wikipedia.org)
Aromatic amino acids are able to absorb light due to their conjugated double bonds. (wikipedia.org)
This characteristic of aromatic amino acids is used to quantify the concentration of proteins in an unknown sample. (wikipedia.org)
Animals obtain aromatic amino acids from their diet, but all plants and micro-organisms must synthesize their aromatic amino acids through the metabolically costly shikimate pathway in order to make them. (wikipedia.org)
These aromatic amino acids are the derivatives of many secondary metabolites, all essential to a plant's biological functions, such as the hormones salicylate and auxin. (wikipedia.org)
Herbicides and antibiotics work by inhibiting these enzymes involved in the biosynthesis of aromatic amino acids, thereby rendering them toxic to plants. (wikipedia.org)
Aromatic L-amino acid decarboxylase Expanded genetic code Logan, Carolynn M. (wikipedia.org)
Cysteine (or sulphur-containing amino acids), tyrosine (or aromatic amino acids), and arginine are always required by infants and growing children. (wikipedia.org)

glycine
All amino acids except glycine (the simplest one) are optically active, having a stereocenter at their α-C atom. (wikipedia.org)
Cysteine can form glutathione (along with glutamic acid and glycine), a powerful antioxidant and detoxifier that functions in many enzyme systems. (healthy.net)
The proteinogenic amino acids are small subset of this group that possess central carbon atom (α- or 2-) bearing an amino group, a carboxyl group, a side chain and an α-hydrogen levo conformation, with the exception of glycine, which is achiral, and proline, whose amine group is a secondary amine and is consequently frequently referred to as an imino acid for traditional reasons, albeit not an imino. (wikipedia.org)
In humans, the glucogenic amino acids are: Alanine Arginine Asparagine Aspartic Cysteine Glutamic Glutamine Glycine Histidine Methionine Proline Serine Valine Amino acids that are both glucogenic and ketogenic (mnemonic "PITTT"): Isoleucine Phenylalanine Threonine Tryptophan Tyrosine Only leucine and lysine are not glucogenic (they are only ketogenic). (wikipedia.org)
Because all amino acids except glycine are chiral, biosynthetic pathways must generate the correct isomer with high fidelity. (wikipedia.org)

Asparagine
In 1806, French chemists Louis-Nicolas Vauquelin and Pierre Jean Robiquet isolated a compound in asparagus that was subsequently named asparagine, the first amino acid to be discovered. (wikipedia.org)
The conversion of aspartate into either the storage amino acid asparagine or aspartate family amino acids may be subject to a coordinated, reciprocal metabolic control, and this biochemical branch point is a part of a larger, coordinated regulatory mechanism of nitrogen and carbon storage and utilization. (wikipedia.org)
Chen H, Pan YX, Dudenhausen EE, Kilberg MS. Amino acid deprivation induces the transcription rate of the human asparagine synthetase gene through a timed program of expression and promoter binding of nutrient-responsive basic region/leucine zipper transcription factors as well as localized histone acetylation. (wikipedia.org)

phenylalanine
A lack of the enzyme phenylalanine hydroxylase, used in tyrosine synthesis, causes phenylketonuria and concurrently renders tyrosine an essential amino acid. (wikipedia.org)
Tyrosine is synthesized by the hydroxylation of phenylalanine, an essential amino acid. (wikipedia.org)

Cysteine
Cysteine and Cystine are sulfur-containing amino acids that are synthesized in the liver and are involved in multiple metabolic pathways. (healthy.net)
Cysteine is formed from homocysteine, which comes from the essential amino acid methionine. (healthy.net)
L-cysteine also forms another amino acid, L-cystine, which is important in hair and nail tissues. (healthy.net)
According to Grantham's distance, most similar amino acids are leucine and isoleucine and the most distant are cysteine and tryptophan. (wikipedia.org)

Alanine
Examples include β-alanine, GABA, and δ-aminolevulinic acid. (wikipedia.org)
β-alanine: an amino acid produced by aspartate 1-decarboxylase and a precursor to coenzyme A and the peptides carnosine and anserine. (wikipedia.org)
General chemical properties §: Values for Asp, Cys, Glu, His, Lys & Tyr were determined using the amino acid residue placed centrally in an alanine pentapeptide. (wikipedia.org)

Histidine
Rose's later work showed that eight amino acids are essential for adult human beings, with histidine also being essential for infants. (wikipedia.org)

Leucine
Leucine may help metabolized to produce energy, as can isoleucine and valine, the other branched-chain amino acids during periods of fasting or starvation. (healthy.net)
Membrane transporters Transcription factors from the basic region/leucine zipper (bZIP) superfamily Growth factors Metabolic enzymes PCAF is recruited specifically to the CHOP amino acid response element (AARE) to enhance the ATF4 transcriptional activity. (wikipedia.org)
Leucine is an example of a typical amino acid. (wikipedia.org)

Lysine
In prokaryotes and plants the synthesis of the essential amino acids lysine and threonine is predominantly regulated by feed-back inhibition of aspartate kinase (AK) and dihydrodipicolinate synthase (DHPS). (wikipedia.org)
Thus, various feedstuffs may be fed in combination to increase net protein utilization, or a supplement of an individual amino acid (methionine, lysine, threonine, or tryptophan) can be added to the feed. (wikipedia.org)

glutamic acid
For example, in the human brain, glutamate (standard glutamic acid) and gamma-amino-butyric acid ("GABA", non-standard gamma-amino acid) are, respectively, the main excitatory and inhibitory neurotransmitters. (wikipedia.org)
A well known example in humans is sickle cell anemia, due to a mutation in beta globin where at position 6 glutamic acid (negatively charged) is exchanged with valine (not charged). (wikipedia.org)

glucogenic amino
The production of glucose from glucogenic amino acids involves these amino acids being converted to alpha keto acids and then to glucose, with both processes occurring in the liver. (wikipedia.org)

selenocysteine
The three additional protein-building amino acids are selenocysteine, pyrrolysine, and N-formylmethionine. (whfoods.org)
However, there are two extra proteinogenic amino acids: selenocysteine and pyrrolysine. (wikipedia.org)
In eukaryotes, there are only 21 proteinogenic amino acids, the 20 of the standard genetic code, plus selenocysteine. (wikipedia.org)
α-ketoacid + glutamate ⇄ amino acid + α-ketoglutarate Glutamate itself is formed by amination of α-ketoglutarate: α-ketoglutarate + NH+ 4 ⇄ glutamate Of the basic set of twenty amino acids (not counting selenocysteine), there are eight that human beings cannot synthesize. (wikipedia.org)

carboxyl group
They are characterized by the presence of a carboxyl group (COOH) and an amino group (NH 2 ) attached to the same carbon at the end of the compound. (factmonster.com)

peptides
Some non-proteinogenic amino acids are incorporated into nonribosomal peptides which are synthesized by non-ribosomal peptide synthetases. (wikipedia.org)

residues in proteins
Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. (wikipedia.org)
Post-translational modification of amino-acid residues in proteins leads to the formation of many proteinaceous, but non-proteinogenic, amino acids. (wikipedia.org)

another amino acid
When the carboxyl carbon atom of one amino acid covalently binds to the amino nitrogen atom of another amino acid with the release of a water molecule, a peptide bond is formed. (factmonster.com)
Most amino acids are synthesized from α-ketoacids, and later transaminated from another amino acid, usually glutamate. (wikipedia.org)

derivatives
The other nine must be consumed (usually as their protein derivatives), and so they are called essential amino acids. (wikipedia.org)
This enzyme belongs to the family of isomerases, specifically those racemases and epimerases acting on amino acids and derivatives. (wikipedia.org)

proteinogenic amin
N-formylmethionine (which is often the initial amino acid of proteins in bacteria, mitochondria, and chloroplasts) is generally considered as a form of methionine rather than as a separate proteinogenic amino acid. (wikipedia.org)

threonine
The last of the 20 common amino acids to be discovered was threonine in 1935 by William Cumming Rose, who also determined the essential amino acids and established the minimum daily requirements of all amino acids for optimal growth. (wikipedia.org)
This led William Cumming Rose to the discovery of the essential amino acid threonine. (wikipedia.org)

carbon
A branched-chain amino acid ( BCAA ) is an amino acid having an aliphatic side-chain with a branch (a central carbon atom bound to three or more carbon atoms). (wikipedia.org)
amino acid əmē´nō [ key ] , any one of a class of simple organic compounds containing carbon, hydrogen, oxygen, nitrogen, and in certain cases sulfur. (factmonster.com)
An amino acid is a carbon atom with a hydrogen atom, an organic acid {COOH}, an amino group {NH2}, and one other chemical group attached. (everything2.com)
A ball-and-stick model structure of polar amino acid glutamine (Gln, Q). Carbon in blue-grey, oxygen in red, nitrogen in green, hydrogen in silver. (openclipart.org)
The key elements of an amino acid are carbon (C), hydrogen (H), oxygen (O), and nitrogen (N), although other elements are found in the side chains of certain amino acids. (wikipedia.org)
In biochemistry, amino acids having both the amine and the carboxylic acid groups attached to the first (alpha-) carbon atom have particular importance. (wikipedia.org)
This amino acid contains a selenol group on its β-carbon Pyrrolysine. (wikipedia.org)
Thus a β amino acid has the amine group bonded to the second carbon away, and a γ amino acid has it on the third. (wikipedia.org)
In plants although the control of carbon fixation and nitrogen assimilation has been studied in detail, relatively little is known about the regulation of carbon and nitrogen flow into amino acids. (wikipedia.org)
The carbon backbones come from the glycolytic pathway, the pentose phosphate pathway, or the citric acid cycle. (wikipedia.org)
In each of the 19 pathways for the generation of chiral amino acids, the stereochemistry at the α-carbon atom is established by a transamination reaction that involves pyridoxal phosphate. (wikipedia.org)
Activated Tetrahydrofolate, a carrier of one-carbon units, plays an important role in the metabolism of amino acids and nucleotides. (wikipedia.org)
Ketogenic amino acids are unable to be converted to glucose as both carbon atoms in the ketone body are ultimately degraded to carbon dioxide in the citric acid cycle. (wikipedia.org)

protein-synthesis
Some natural amino acids, such as norleucine, are misincorporated translationally into proteins due to infidelity of the protein-synthesis process. (wikipedia.org)
The following illustrates the structures and abbreviations of the 21 amino acids that are directly encoded for protein synthesis by the genetic code of eukaryotes. (wikipedia.org)
Feedback and allosteric mechanisms ensure that all twenty amino acids are maintained in sufficient amounts for protein synthesis and other processes. (wikipedia.org)
Consequently, only a subset of the amino acids used in protein synthesis are essential nutrients. (wikipedia.org)

essential
Carnitine has only recently been noted as an important amino acid (the L- form only) essential to our health. (healthy.net)
Amino acids can be essential, nonessential or conditional. (news-medical.net)
The three proteinogenic BCAAs are among the nine essential amino acids for humans, accounting for 35% of the essential amino acids in muscle proteins and 40% of the preformed amino acids required by mammals. (wikipedia.org)
The Food and Nutrition Board (FNB) of the U.S. Institute of Medicine set Recommended Dietary Allowances (RDAs) for essential amino acids in 2002. (wikipedia.org)
Nine proteinogenic amino acids are called "essential" for humans because they cannot be produced from other compounds by the human body and so must be taken in as food. (wikipedia.org)
Essential amino acids may also differ between species. (wikipedia.org)
An essential amino acid cannot be synthesized in humans and must, therefore, be supplied in the diet. (wikipedia.org)
Conditionally essential amino acids are not normally required in the diet, but must be supplied exogenously to specific populations that do not synthesize it in adequate amounts. (wikipedia.org)
The amino acid response pathway is triggered by shortage of any essential amino acid, and results in an increase in activating transcription factor ATF4, which in turn affect many process by sundry pathways to limit or increase the production of other proteins. (wikipedia.org)
PDCAAS and DIAAS are the two major protein standards which determine the completeness of proteins by their unique composition of essential amino acids. (wikipedia.org)
Amino acids that must be obtained from the diet are called essential amino acids. (wikipedia.org)
The pathways for the biosynthesis of essential amino acids are much more complex than those for the nonessential ones. (wikipedia.org)
An essential amino acid, or indispensable amino acid, is an amino acid that cannot be synthesized de novo (from scratch) by the organism, and thus must be supplied in its diet. (wikipedia.org)
F V T W M L I K H). Six other amino acids are considered conditionally essential in the human diet, meaning their synthesis can be limited under special pathophysiological conditions, such as prematurity in the infant or individuals in severe catabolic distress. (wikipedia.org)
The following table lists the WHO and United States recommended daily amounts currently in use for essential amino acids in adult humans, together with their standard one-letter abbreviations. (wikipedia.org)
These concepts are important in the livestock industry, because the relative lack of one or more of the essential amino acids in animal feeds would have a limiting effect on growth and thus on feed conversion ratio. (wikipedia.org)
Although proteins from plant sources tend to have relatively lower concentrations of protein by mass in comparison to protein from eggs or milk, they are nevertheless "complete" in that they contain at least trace amounts of all of the amino acids that are essential in human nutrition. (wikipedia.org)
Certain native combinations of foods, such as corn and beans, soybeans and rice, or red beans and rice, contain the essential amino acids necessary for humans in adequate amounts. (wikipedia.org)
they have both chlorophyll as do plants, and also all the essential amino acids, as do animal proteins. (wikipedia.org)
The distinction between essential and non-essential amino acids is somewhat unclear, as some amino acids can be produced from others. (wikipedia.org)

pyrrolysine
Pyrrolysine, sometimes considered "the 22nd amino acid", is not used by humans. (wikipedia.org)

Pathways
Next ketoacid reductisomerase reduces the acetohydroxy acids from the previous step to yield dihydroxyacids in both the valine and isoleucine pathways. (wikipedia.org)
Amino acid synthesis is the set of biochemical processes (metabolic pathways) by which the various amino acids are produced from other compounds. (wikipedia.org)
The pathways for the synthesis of nonessential amino acids are quite simple. (wikipedia.org)

inhibitory
There are inhibitory amino acids ( IAA ) or excitatory amino acids ( EAA ). (wikipedia.org)

synthesis
A transamination reaction takes place in the synthesis of most amino acids. (wikipedia.org)

common amino acids
In addition to these 20, scientists have synthesized more than 70 artificial amino acids that are not found in animals, and more than 100 less common amino acids also occur in biological systems, particularly in plants. (factmonster.com)

Nonessential Amino Acids
Nonessential amino acids are produced in the body. (wikipedia.org)

humans
R C G Q P Y). Five amino acids are dispensable in humans, meaning they can be synthesized in the body. (wikipedia.org)

nitrogen
Ammonia is the source of nitrogen for all the amino acids. (wikipedia.org)
Higher organisms consume the fixed nitrogen to synthesize amino acids, nucleotides, and other nitrogen-containing biomolecules. (wikipedia.org)

ornithine
Many amino acids, such as ornithine, are metabolic intermediates produced biosynthetically, but not incorporated translationally into proteins. (wikipedia.org)

aspartate
The metabolic regulation of expression of an Arabidopsis thaliana aspartate kinase/homoserine dehydrogenase (AK/HSD) gene, which encodes two linked key enzymes in the biosynthetic pathway of aspartate family amino acids has been studied. (wikipedia.org)

metabolism
Some non-protein building amino acids have been well-researched from the standpoint of metabolism, but less well investigated from the standpoint of food. (whfoods.org)
Amino acid metabolism Chapter on Amino acid catabolism in Biochemistry by Jeremy Berg, John Tymoczko, Lubert Stryer. (wikipedia.org)
ISBN 0-7167-4955-6 Accessed 2007-03-17 Amino acid metabolism Chapter on Protein Turnover and Amino Acid Catabolism in Biochemistry by Jeremy Berg, John Tymoczko, Lubert Stryer. (wikipedia.org)

living organisms
With a few important exceptions, living organisms keep all their amino acids in the "L" configuration. (wikipedia.org)

molecule
Amino "head" of one amino acid can be linked to the carboxyl tail of another by removal of a molecule of water (Peptide bond). (everything2.com)
sequence of amino acids in polypeptide chain determines the characters of the protein molecule. (everything2.com)
In these structures, the amine group displaced further from the carboxylic acid end of the amino acid molecule. (wikipedia.org)
Forming a peptide bond results in elimination of a molecule of water, so the mass of an amino acid unit within a protein chain is reduced by 18.01524 Da. (wikipedia.org)

Enzymes
The enzymes vary considerably in structure although they all perform the same type of reaction by binding ATP, one specific amino acid and its corresponding tRNA. (wikipedia.org)

proteins during tran
Proteinogenic amino acids are amino acids that are incorporated biosynthetically into proteins during translation. (wikipedia.org)

eukaryotes
Despite the use of only 22 amino acids (21 in eukaryotes) by the translational machinery to assemble proteins (the proteinogenic amino acids), over 140 amino acids are known to occur naturally in proteins and thousands more may occur in nature or be synthesized in the laboratory. (wikipedia.org)
Eukaryotes can synthesize some of the amino acids from other substrates. (wikipedia.org)

biochemistry
In biochemistry, non-coded or non-proteinogenic amino acids are those not naturally encoded or found in the genetic code of any organism. (wikipedia.org)

carboxylic acid
Technically, any organic compound with an amine (-NH2) and a carboxylic acid (-COOH) functional group is an amino acid. (wikipedia.org)

individual amino
When making nutritional recommendations for our everyday diet, health scientists have expressed much more confidence in estimating our total protein needs than in estimating our need for individual amino acids. (whfoods.org)
Part of the difficulty in determining our need for individual amino acids involves the interconversion of amino acids that is constantly taking place in our body. (whfoods.org)

sequence
The manner or sequence in which these amino acids combine to form a protein determines the 3-dimensional structure and function, which is unique to the particular protein. (news-medical.net)
The sequence of amino acids in a protein and hence protein function are determined by the genetic code. (everything2.com)
aa-tRNA + AMP The amino acid is coupled to the penultimate nucleotide at the 3'-end of the tRNA (the A in the sequence CCA) via an ester bond (roll over in illustration). (wikipedia.org)
It also has a unique carbohydrate moiety and a unique repetitive amino acid sequence which give it a high affinity for bonding to adhering proteins resulting in a tightening, anti-wrinkle effect. (wikipedia.org)
Amino acid replacement is a change from one amino acid to a different amino acid due to point mutation in DNA sequence. (wikipedia.org)
It is caused by nonsynonymous missense mutation which alters the codon sequence to code other amino acid instead of the originals. (wikipedia.org)
The magnitude of this process may vary depending on how similar or dissimilar the replaced amino acids are, as well as on their position in the sequence or the structure. (wikipedia.org)

racemization
When an organism dies, control over the configuration of the amino acids ceases, and the ratio of D to L moves from a value near 0 towards an equilibrium value near 1, a process called racemization. (wikipedia.org)
The rate at which racemization proceeds depends on the type of amino acid and on the average temperature, humidity, acidity (pH), and other characteristics of the enclosing matrix. (wikipedia.org)
These are important for amino acid dating because racemization occurs much faster in warm, wet conditions compared to cold, dry conditions. (wikipedia.org)
Data from the geochronological analysis of amino acid racemization has been building for thirty-five years. (wikipedia.org)
Verification of radiocarbon and other dating techniques by amino acid racemization and vice versa has occurred. (wikipedia.org)
Amino acid racemization also has a role in tissue and protein degradation studies, particularly useful in developing museum preservation methods. (wikipedia.org)

tryptophan
Sometimes amino acids are referred to with an L- in front of the name, as in L-tryptophan . (everything2.com)

converted into glucose
A glucogenic amino acid is an amino acid that can be converted into glucose through gluconeogenesis. (wikipedia.org)

catabolism
Cellular catabolism breaks amino acids down into smaller fragments. (factmonster.com)

polarity
There are three "types" of amino acids, as defined by the polarity of their subgroups. (everything2.com)
Epstein's coefficient of difference is based on the differences in polarity and size between replaced pairs of amino acids. (wikipedia.org)

neurotransmitter
An amino acid neurotransmitter is an amino acid which is able to transmit a nerve message across a synapse . (wikipedia.org)
Amino acid neurotransmitter release ( exocytosis ) is dependent upon calcium Ca 2+ and is a presynaptic response. (wikipedia.org)
γ-Aminobutyric acid (GABA): a neurotransmitter in animals. (wikipedia.org)

synthesize
Of the 20-odd amino acids, there are 8 (or 9 , due to the expert factor ) that the body cannot synthesize for itself. (everything2.com)
Not all organisms are able to synthesize all amino acids. (wikipedia.org)

peptide chains
They include the 22 proteinogenic ("protein-building") amino acids, which combine into peptide chains ("polypeptides") to form the building-blocks of a vast array of proteins. (wikipedia.org)
Silk amino acids are produced by hydrolyzing (or breaking apart) silk proteins into smaller peptide chains, typically 18 to 19 amino acids in length. (wikipedia.org)

2000
Proteins tend to be typically comprised of between 50 to 2000 amino acids joined end-to-end in many different combinations. (news-medical.net)

Molecular
Amino acid dating is a dating technique used to estimate the age of a specimen in paleobiology, molecular paleontology, archaeology, forensic science, taphonomy, sedimentary geology and other fields. (wikipedia.org)
In molecular biology, the amino acid kinase domain is a protein domain. (wikipedia.org)
Silk amino acids have a lower molecular weight than silk protein powders and are moisturizing to skin and hair. (wikipedia.org)

biological
All biological tissues contain amino acids. (wikipedia.org)
Many important proteinogenic and non-proteinogenic amino acids have biological functions. (wikipedia.org)
Because of their biological significance, amino acids are important in nutrition and are commonly used in nutritional supplements, fertilizers, and food technology. (wikipedia.org)
Measures include the biological value, net protein utilization, protein efficiency ratio, protein digestibility-corrected amino acid score and complete proteins concept. (wikipedia.org)

ketone bodies
This is in contrast to the ketogenic amino acids, which are converted into ketone bodies. (wikipedia.org)
A ketogenic amino acid is an amino acid that can be degraded directly into acetyl-CoA, which is the precursor of ketone bodies. (wikipedia.org)

starvation
Amino acid response (AAR) is the mechanism triggered in mammalian cells by amino acid starvation. (wikipedia.org)

chirality
Some amino acids contain the opposite absolute chirality, chemicals that are not available from normal ribosomal translation/transcription machinery. (wikipedia.org)
At this step, the chirality of the amino acid is established. (wikipedia.org)

GABA
In contrast, non-proteinogenic amino acids are amino acids that are either not incorporated into proteins (like GABA, L-DOPA, or triiodothyronine), misincorporated in place of a genetically encoded amino acid, or not produced directly and in isolation by standard cellular machinery (like hydroxyproline). (wikipedia.org)

organic
Amino acids are organic compounds containing amine (-NH2) and carboxyl (-COOH) functional groups, along with a side chain (R group) specific to each amino acid. (wikipedia.org)

genetic code
The method that scientists have used to determine the protein-building role of these 20 core amino acids involves our genetic code. (whfoods.org)
About 500 naturally occurring amino acids are known (though only 20 appear in the genetic code) and can be classified in many ways. (wikipedia.org)
Codon-tRNA combinations not found in nature can also be used to "expand" the genetic code and form novel proteins known as alloproteins incorporating non-proteinogenic amino acids. (wikipedia.org)
(wikipedia.org)

bacteria
Occurrence of amino acids is based on 135 Archaea, 3775 Bacteria, 614 Eukaryota proteomes and human proteome (21 006 proteins) respectively. (wikipedia.org)

enzyme
Amino acid oxidoreductases are oxidoreductases, a type of enzyme, that act upon amino acids. (wikipedia.org)
In enzymology, an amino-acid racemase (EC 5.1.1.10) is an enzyme that catalyzes the chemical reaction an L-amino acid ⇌ {\displaystyle \rightleftharpoons } a D-amino acid Hence, this enzyme has one substrate, L-amino acid, and one product, D-amino acid. (wikipedia.org)
The systematic name of this enzyme class is amino-acid racemase. (wikipedia.org)
This enzyme is also called L-amino acid racemase. (wikipedia.org)