Adding to a broad collection of long wavelength FRET protease assay kits, AnaSpec has introduced the SensoLyte™ 520 Cathepsin S Assay Kit.
The SensoLyte™ 520 Cathepsin S Activity Assay Kit is a homogeneous assay that can be used to detect the activity of Cathepsin S in biological samples or in purified enzyme preparations. A unique long wavelength 5-FAM/QXL™ 520 FRET peptide substrate is used in this kit. When active Cathepsin S cleaves this FRET substrate, it results in an increase of 5-FAM fluorescence, which can be monitored at Ex/Em = 490 nm/520 nm. The long wavelength fluorescence of 5-FAM is less interfered by the autofluorescence of cell components and test compounds.
Cathepsin S is a lysosomal cysteine proteinase of the papain family. It plays a major role in the degradation of the invariant peptide chain associated with the major histocompatibility complex and thus affects antigen presentation.1, 2 Since antigen presentation is the key to immune response, Cathepsin S has been validated as an immunomodulatory target.3, 4 Cathepsin S is also involved in several pathologies including atherosclerosis, cancer, obesity and their associated diseases.5-9
AnaSpec also provides the SensoLyte 440 Cathespsin S Activity Assay Kit. The substrate used in this kit releases the AMC (7-amino-4-methylcoumarin) fluorophore upon Cathepsin S cleavage. AMC has bright blue fluorescence that can be detected with excitation at 354 nm and emission at 442 nm.
About AnaSpec, Inc.
AnaSpec, Inc. is a leading provider of integrated proteomics solutions to pharmaceutical, biotech, and academic research institutions throughout the world. With a vision for innovation through synergy, AnaSpec focuses on three core technologies: peptides, detection reagents (dyes, assay kits, & antibodies), and combinatorial chemistry.
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8. Taleb, S. et al, J. Clin. Endocrinol. Metab. 91, 1042 (2006)
9. Wang, B. et al, J. Biol. Chem. 281, 6020 (2006).