An amino acid that is a constituent of most proteins, especially collagen.
- ‘The first five amino acids obtained were glycine, proline, threonine, glycine, and threonine.’
- ‘The amount of the amino acids threonine, proline and histidine were also increased in roots of slag-cultivated maize plants.’
- ‘The cationic component of the hemolymph is frequently replaced by potassium and free amino acids such as glutamate, proline, lysine and glycine.’
- ‘Active oxygen species cause protein damage through direct interaction with specific amino acids (lysine, arginine, proline or threonine).’
- ‘The GPP protein also contains several regions rich in alanine, proline, histidine, and glutamine.’
Early 20th century: contraction of the chemical name p(yr)rol(id)ine -2-carboxylic acid.