释义 |
amino acid
amino acidn. Any of various compounds containing an amino group (NH2), a carboxylic acid group (COOH), and a distinctive side chain, especially any of the 20 amino acids that link together to form proteins. Some amino acids (called nonessential) can be synthesized in the human body, while others (called essential) must be obtained through the diet.amino acid n (Biochemistry) any of a group of organic compounds containing one or more amino groups, -NH2, and one or more carboxyl groups, -COOH. The alpha-amino acids RCH(NH2)COOH (where R is either hydrogen or an organic group) are the component molecules of proteins; some can be synthesized in the body (nonessential amino acids) and others cannot and are thus essential components of the diet (essential amino acids) ami′no ac′id n. any of a class of organic compounds that contains at least one amino group, –NH2, and one carboxyl group, –COOH: the alpha-amino acids, RCH(NH2)COOH, are the building blocks from which proteins are constructed. [1895–1900] a·mi·no acid (ə-mē′nō) Any of a large number of compounds that are found in living cells, contain carbon, oxygen, hydrogen, and nitrogen, and join together to form proteins. ♦ About 20 amino acids are needed by animal cells to produce proteins, but only about half, called nonessential amino acids, can be produced by animal cells. The remaining half, called , essential amino acids, must be obtained from food.ThesaurusNoun | 1. | amino acid - organic compounds containing an amino group and a carboxylic acid group; "proteins are composed of various proportions of about 20 common amino acids"aminoalkanoic acidalanine - a crystalline amino acid that occurs in many proteinsasparagine - a crystalline amino acid found in proteins and in many plants (e.g., asparagus)aspartic acid - a crystalline amino acid found in proteins and occurring naturally in sugar beets and sugar canecanavanine - an amino acid found in the jack beancitrulline - an amino acid that does not occur in proteins but is an intermediate in the conversion of ornithine to argininecysteine - an amino acid containing sulfur that is found in most proteins; oxidizes on exposure to air to form cystinecystine - a crystalline amino acid found in proteins (especially keratin); discovered in bladder stonesdihydroxyphenylalanine, dopa - amino acid that is formed in the liver and converted into dopamine in the brainessential amino acid - an amino acid that is required by animals but that they cannot synthesize; must be supplied in the dietGABA, gamma aminobutyric acid - an amino acid that is found in the central nervous system; acts as an inhibitory neurotransmitterglutamic acid, glutaminic acid - an amino acid occurring in proteins; important in the nitrogen metabolism of plants; used in monosodium glutamate to enhance the flavor of meatsglutamine - a crystalline amino acid occurring in proteins; important in protein metabolismglycine - the simplest amino acid found in proteins and the principal amino acid in sugar canehydroxyproline - a crystalline amino acid obtained from gelatin or collageniodoamino acid - an amino acid with iodine addedornithine - an amino acid that does not occur in proteins but is important in the formation of ureaproline - an amino acid that is found in many proteins (especially collagen)organic compound - any compound of carbon and another element or a radicalprotein - any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers of amino acids; essential in the diet of animals for growth and for repair of tissues; can be obtained from meat and eggs and milk and legumes; "a diet high in protein"creatin, creatine - an amino acid that does not occur in proteins but is found in the muscle tissue of vertebrates both in the free form and as phosphocreatine; supplies energy for muscle contractionsarcosine - a sweetish crystalline amino acidserine - a sweetish crystalline amino acid involved in the synthesis by the body of cysteinethyronine - a phenolic amino acid of which thyroxine is a derivativetyramine - amino acid derived from tyrosine; has a sympathomimetic action; found in chocolate and cola drinks and ripe cheese and beer; "patients taking MAOIs should avoid foods containing tyramine"tyrosine - an amino acid found in most proteins; a precursor of several hormones | TranslationsAmino acid
amino [ah-me´no, am´ĭ-no] the monovalent radical NH2, when not united with an acid radical.amino acid any of a class of organic compounds containing the amino (NH2) and the carboxyl (COOH) groups, occurring naturally in plant and animal tissues and forming the chief constituents of protein. Twenty amino acids are necessary for protein synthesis. Eleven (the nonessential amino acids) can be synthesized by the human body and thus are not specifically required in the diet: alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine. Nine (the essential amino acids) cannot be synthesized by humans and thus are required in the diet: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Structural formulas for some representative amino acids. From Applegate, 2000. Protein foods that provide the essential amino acids are known as complete proteins; these include proteins from animal sources, such as meat, eggs, fish, and milk. Proteins that cannot supply the body with all the essential amino acids are known as incomplete proteins; these are the vegetable proteins most abundantly found in legumes (peas and beans), as well as certain grains. Because different incomplete proteins lack different amino acids, specific combinations can provide all of the essential amino acids. In certain inherited or acquired disorders of metabolism, specific amino acids accumulate in the blood (aminoacidemia) or are excreted in excess in the urine (aminoaciduria). Urinary amino acid levels are increased in liver disease, muscular dystrophies, phenylketonuria (PKU), lead poisoning, and folic acid deficiency.a·mi·no ac·id (AA, aa), (ă-mē'nō as'id), An organic acid in which one of the hydrogen atoms on a carbon atom has been replaced by NH2. Usually refers to an aminocarboxylic acid. However, taurine is also an amino acid. See also: α-amino acid. amino acidn. Any of various compounds containing an amino group (NH2), a carboxylic acid group (COOH), and a distinctive side chain, especially any of the 20 amino acids that link together to form proteins. Some amino acids (called nonessential) can be synthesized in the human body, while others (called essential) must be obtained through the diet.ami·no ac·id (AA, aa) (ă-mē'nō as'id) An organic acid in which one of the hydrogen atoms on a carbon atom has been replaced by NH2. Usually refers to an aminocarboxylic acid. However, taurine is also an amino acid. See also: alpha (α)-amino acidFig. 28 Amino acid . Structure of a generalized amino acid.Fig. 27 Amino acid . The 20 amino acids commonly found in protein, with the three-letter and, in brackets, one-letter abbreviation for each. amino acid a building block of protein, containing a carboxyl group (COOH) and an amino group (NH2), both attached to the same carbon atom. Over 80 amino acids are known to occur naturally, with 20 found commonly in proteins (see Fig. 27 ), each with a different side chain, called an ‘R’ group (see Fig. 28 ). Each of these common amino acids is described under its own heading. Many amino acids can be synthesized in the body from other amino acids by a process called TRANSAMINATION, although most organisms have a number of ESSENTIAL AMINO ACIDS that must be taken in with the diet. Each amino acid is coded by at least one triplet of DNA bases (see GENETIC CODE), and the string of amino acids making up a protein is joined by PEPTIDE BONDS to form a POLYPEPTIDE CHAIN. The sequence of amino acids is the PRIMARY STRUCTURE. Amino acids are soluble in water but vary considerably in their solubility. When in solution they are ionized (see ZWITTERION) and generally are electrically neutral with a pH known as the ISOELECTRIC POINT. They are amphoteric, i.e. acting as acids or bases if the pH is shifted. Amino acidAmino acids are small molecules that are used as building blocks for all proteins. Some amino acids are also used in the body for the manufacture of hormones. There are about 20 nutritionally important amino acids, including glutamic acid, glycine, methionine, lysine, tryptophan, serine, and glycine.Mentioned in: Amino Acid Disorders Screening, Cystinuria, Homocysteine, Phenylketonuria, Sickle Cell Disease, Stress Reduction, Vitamin B 6 Deficiencyami·no ac·id(aa) (ă-mē'nō as'id) An organic acid in which one of the hydrogen atoms on a carbon atom has been replaced by NH2. Usually refers to an aminocarboxylic acid. However, taurine is also an amino acid. See also: alpha (α)-amino acidPatient discussion about Amino acidQ. what are Amino Acids and what are their for? how do i need to do to keep it "going "? A. Amino acids are the basic structural building units of proteins. They form short polymer chains called peptides or longer chains called either polypeptides or proteins. The process of such formation from an mRNA template is known as translation, which is part of protein biosynthesis. Twenty amino acids are encoded by the standard genetic code and are called proteinogenic or standard amino acids. Other amino acids contained in proteins are usually formed by post-translational modification, which is modification after translation in protein synthesis. These modifications are often essential for the function or regulation of a protein; for example, the carboxylation of glutamate allows for better binding of calcium cations, and the hydroxylation of proline is critical for maintaining connective tissues and responding to oxygen starvation. For full article: http://en.wikipedia.org/wiki/Amino_acid Hope this helps. More discussions about Amino acidFinancialSeeAASee ANDVT Airterm See AAamino acid Related to amino acid: essential amino acidSynonyms for amino acidnoun organic compounds containing an amino group and a carboxylic acid groupSynonymsRelated Words- alanine
- asparagine
- aspartic acid
- canavanine
- citrulline
- cysteine
- cystine
- dihydroxyphenylalanine
- dopa
- essential amino acid
- GABA
- gamma aminobutyric acid
- glutamic acid
- glutaminic acid
- glutamine
- glycine
- hydroxyproline
- iodoamino acid
- ornithine
- proline
- organic compound
- protein
- creatin
- creatine
- sarcosine
- serine
- thyronine
- tyramine
- tyrosine
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