A highly sensitive fluorescence resonance energy transfer (FRET) peptide substrate (excitation max.: ~350 nm; emission max.: ~490), based on the GVNLDAEF sequence derived from the β-secretase site of the Swedish mutation of Amyloid Precursor Protein. Hydrolysis of the substrate at Leu-Asp bond by β-secretase results in fluorescence enhancement. Reported Kcat/km values (min-1/μM) for pro-mempasin 2 and its proteolytically activated species Leu28p-mempasin 2 are 0.044 and 0.040, respectively (at pH 4.5, 37°C).
