Translations:Amino acid/65/en

Non-proteinogenic amino acids that are found in proteins are formed by post-translational modification. Such modifications can also determine the localization of the protein, e.g., the addition of long hydrophobic groups can cause a protein to bind to a phospholipid membrane. Examples:

• the carboxylation of glutamate allows for better binding of calcium cations,
• Hydroxyproline, generated by hydroxylation of proline, is a major component of the connective tissue collagen.
• Hypusine in the translation initiation factor EIF5A, contains a modification of lysine.