- any of a large group of organic acids containing a carboxyl group, COOH, and an amino group, NH
- any of the 25 amino acids that link together into polypeptide chains to form proteins that are necessary for all life: in general, they are water-soluble, crystalline, amphoteric electrolytes having mirror-image isomeric forms with right and left optical activity: ten of these () cannot be synthesized by the human body and must be consumed
See amino acid in American Heritage Dictionary 4
An organic compound containing an amino group (NH2), a carboxylic acid group (COOH), and any of various side groups, especially any of the 20 compounds that have the basic formula NH2CHRCOOH, and that link together by peptide bonds to form proteins or that function as chemical messengers and as intermediates in metabolism.
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