Cathepsin S Fluorogenic Substrate, Ac-KQKLR-AMC

Ac-KQKLR-AMC is a fluorogenic peptide substrate used to measure cathepsin S activity. Cathepsin S is a lysosomal cysteine protease with important roles in antigen processing and MHC class II peptide loading. Cleavage of the peptide releases AMC, allowing continuous or endpoint fluorescence-based measurement of enzyme activity.

• cathepsin S activity assays
• antigen-processing research
• lysosomal protease studies
• cathepsin inhibitor screening

AMC fluorescence is typically monitored near 354 nm excitation and 442 nm emission. Reducing conditions and assay pH can strongly influence cysteine-protease activity and should be standardized.

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