Definition of amino acid in US English:

amino acid


  • A simple organic compound containing both a carboxyl (—COOH) and an amino (—NH₂) group.

    Amino acids occur naturally in plant and animal tissues and are the basic constituents of proteins

    as modifier ‘the amino-acid sequence of a protein’
    • ‘Protein molecules are large biological polymers of small molecules called amino acids, and each protein has a unique amino-acid sequence.’
    • ‘Homocysteine is produced from the amino acid methionine, which is found in normal dietary protein.’
    • ‘To tackle this problem a variety of approaches have been developed to predict the three-dimensional structure of a protein given its amino-acid sequence.’
    • ‘Two known enzymes catabolize the essential amino acid tryptophan in mammals.’
    • ‘The simplest amino acid is glycine which contains a hydrogen atom as its side group.’


amino acid

/əˌmēnō ˈasəd//əˌminoʊ ˈæsəd/