Molecular Weight: 620.54Salt Form: N/APurity: >96%Sequence (3-letter): Z-Ala-Ala-Asp-AFCSequence (1-letter): (Z)AAD(AFC)Storage: -20 °C or belowZ-Ala-Ala-Asp-AFC is a fluorogenic substrate for cathepsin S a lysosomal cysteine protease with important roles in MHC Class II antigen presentation and nociception. Cathepsin S also cleaves several extracellular matrix proteins (laminin fibronectin elastin osteocalcin) and glycosaminoglycans (heparin sulfate chondroitin sulfate).Activity is quantified by release of free fluorescent 7-amino-4-trifluoromethylcoumarin (AFC) which excites at 395-400 nm and emits at 495-505 nm.