An amino acid is a molecule containing an amine group, a carboxylic acid and a side chain, R, that varies depending on the amino acid.
General structure
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The general chemical structure of an alpha amino acid.
Proteinogenic amino acids
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These amino acids are used in proteins and divided up into essential and non-essential amino acids.
Essential | Non-essential | ||
---|---|---|---|
Isoleucine | Alanine | ||
Leucine | Arginine | ||
Lysine | Asparagine | ||
Methionine* | Aspartic acid | ||
Phenylalanine | Cysteine* | ||
Threonine | Glutamic acid | ||
Tryptophan | Glutamine | ||
Valine | Glycine | ||
- | - | Histidine | |
- | - | Proline | |
- | - | Selenocysteine | |
- | - | Serine | |
- | - | Tyrosine |
- - These amino acids contain sulphur atoms.