Human BACE2 Synthetic Peptide. BACE2 or Beta Secretase 2 is responsible for the proteolytic processing of the amyloid precursor protein (APP). BACE2 cleaves APP between residues 690 and 691. This cleavage leads to the generation and extracellular release of beta-cleaved soluble APP. BACE2 is also know to cleave APP between residues 671 and 672. Accumulation of APP is a signature of Alzheimer disease and frequent complication of adult Down syndrome patients.