Amyloid β-Protein (3-42) is the precursor of Pyr peptide. Pyroglutamate-modified Aβ (pEAβ) (3-42) is the core of the amyloid template block in Alzheimer's disease. pEAβ (3-42) accelerated the aggregation of Aβ (1-42), while Aβ (1-42) significantly slowed the primary and secondary nucleation of pEAβ (3-42) [1].