Proline is a unique proteinogenic amino acid with a cyclic structure. Its nitrogen atom is locked within a five-member ring, and peptides containing at least three consecutive proline residues are known to form polyproline helices, a feature that facilitates protein folding. Synthesis can be challenging due to steric hindrance and the slow rate of peptide bond formation, but our chemists have experience synthesising such peptides. Contact info@altabioscience.com to discuss your requirements.