This beta-amyloid peptide (1-42) has Ile31 substituted with Pro31. Substitution of Ile31 by the helix-breaking amino acid, proline, completely abrogates the oxidative stress and neurotoxic properties of beta-amyloid (1-42).
H - Asp - Ala - Glu - Phe - Arg - His - Asp - Ser - Gly - Tyr - Glu - Val - His - His - Gln - Lys - Leu - Val - Phe - Phe - Ala - Glu - Asp - Val - Gly - Ser - Asn - Lys - Gly - Ala - Pro - Ile - Gly - Leu - Met - Val - Gly - Gly - Val - Val - Ile - Ala - OH