amino acid

noun, Biochemistry

any of a class of organic compounds that contains at least one amino group, –NH ₂ , and one carboxyl group, –COOH: the alpha-amino acids, RCH(NH ₂)COOH, are the building blocks from which proteins are constructed.

Compare essential amino acid.

Origin

1895-1900

Examples from the web for amino acid

The seaweed absorbs the extra nitrogen and converts it into an amino acid-the building block of protein-called arginine.
T cells can discriminate between self and nonself on the basis of a change in a single amino acid in a peptide.
Varying food intake and eating enough food takes care of amino acid balance.
It is a complete amino acid and is unusually high in protein for a seed.
It's a fact that asparagus, a member of the lily family, contains the sulfurous amino acid methionine.
The protein in question contains a lot of an amino acid called histidine.
So the amino acid chain is surrounded by water molecules.
The researchers made another genetic mutation that interfered with the breakdown of the amino acid tyrosine.
When this chemical reacts with amino acid compounds it detects fingerprints on paper.
Their amino acid sequence stays the same but their already abnormal structures become increasingly twisted.

British Dictionary definitions for amino acid

amino acid

noun

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)

amino acid in Medicine

amino acid n.
Abbr. AA
Any of various organic acids containing both an amino group and a carboxyl group, especially any of the 20 or more compounds that link together to form proteins.

amino acid in Science

amino acid
Any of a large number of compounds found in living cells that contain carbon, oxygen, hydrogen, and nitrogen, and join together to form proteins. Amino acids contain a basic amino group (NH₂) and an acidic carboxyl group (COOH), both attached to the same carbon atom. Since the carboxyl group has a proton available for binding with the electrons of another atom, and the amino group has electrons available for binding with a proton from another atom, the amino acid behaves as an acid and a base simultaneously. Twenty of the naturally occurring amino acids are the building blocks of proteins, which they form by being connected to each other in chains. Eight of those twenty, called essential amino acids, cannot be synthesized in the cells of humans and must be consumed as part of the diet. The remaining twelve are nonessential amino acids.