Calpain Substrate III, Fluorogenic

A fluorogenic FRET peptide with a substrate sequence that is optimized for calpain-1 and -2 based on 106 known cleavage sites. It is cleaved by mammalian calpains with higher efficiency (k_cat/K_mx10^-2 (M^-1s^-1) = 69.8, 38.5, 20.0, 6.81, 3.58, 0.05, and <0.05 for calpain-2, trypsin, papain, calpain-B, calpain-A, chymotrypsin, and cathepsin-B, respectively). It is kinetically superior to other commonly used calpain substrates, such as LY-AMC (Cat. No. 208731) and α-spectrin cleavage site-based substrate (Cat. No. 208748). Has been used successfully in monitoring calpain activity in intact Drosophila S2 cells (cellular incorporation achieved with a lipofection reagent) and in COS-7 cell lysate.

Cell permeable: no

Primary Target
Substrate sequence that is optimized for calpain-1 and -2

Product does not compete with ATP.

Reversible: no

kcat/Kmx10-2 (M-1s-1) = 69.8, 38.5, 20.0, 6.81, 3.58, 0.05, and <0.05 for calpain-2, trypsin, papain, calpain-B, calpain-A, chymotrypsin, and cathepsin-B, respectively

Packaged under inert gas

Supplied as a trifluoroacetate salt.

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 3 months at -20°C.

DABCYL-Thr-Pro-Leu-Lys~Ser-Pro-Pro-Pro-Ser-Pro-Arg-EDANS

Tompa, P., et al. 2004. J. Biol. Chem.279, 20775.

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany

Toxicity: Irritant (B)