Rapidly becoming the new industry
standard for long wavelength FRET protease assay kits, AnaSpec's SensoLyte™
suite is pleased to introduce the latest member to its growing family – 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
Figure 1. Detection of Cathepsin S with the SensoLyte™
520 Cathepsin S Assay Kit. This kit can detect 0.1 ng of enzyme (0.03 mUnits).
AnaSpec also provides the
Cathepsin 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.
Related Products and Services:
Cathepsin S Activity Assay Kit (Ex/Em = 354 nm/442 nm)
Cathepsin D Activity Assay Kit (Ex/Em = 490 nm/520 nm)
Cathepsin D Activity Assay Kit (Ex/Em = 330 nm/390 nm)
Substrates, Inhibitors & Peptide
Secretase Assay Kits
1. Honey, K and AY. Rudensky, Nat. Rev. Immunol. 3,
2. Hsieh, CS. et al, J. Immunol. 168, 2618 (2002).
3. Gupta, S. et al, Expert Opin. Ther. Targets 12,
4. Thurmond, RL et al, Curr. Opin. Investi.g Drugs 6,
5. Sukhova, GK. et al, J. Clin. Invest. 111,
6. Taleb, S. et al, FASEB J. 19, 1540 (2005).
7. Liu, J. et al, Atherosclerosis 186, 411 (2006).
8. Taleb, S. et al, J. Clin. Endocrinol. Metab. 91,
9. Wang, B. et al, J. Biol. Chem. 281, 6020 (2006).