chymotrypsin-like proteasome

Aprotinin (Traskolan) is a broad-spectrum serine protease (BPTI) inhibitor that inhibits the activity of a number of different esterases and proteases. Aprotinin is an antifibrinolytic agent used to minimize hemorrhage during complex surgical procedures.

Z-LLL-AMC is a fluorogenic substrate for the chymotrypsin-like activity of the 26S proteasome or 20S proteolytic core. Chymotrypsin-like activity can be quantified by fluorescent detection of free AMC (also known as 7-amino-4-methylcoumarin), which is excited at 340-360 nm and emits at 440-460 nm. Z-LLL-AMC is typically used in cell lysates after experimental treatment.

Z-Gly-Pro-Phe-Leu-CHO (Z-GPFL-CHO) is a tetrapeptide aldehyde that acts as a selective and potent proteasome inhibitor, with inhibition constants (Ki) of 1.5 µM for branched-chain amino acid-preferred, 2.3 µM for small neutral amino acid-preferred, and 40.5 µM for chymotrypsin-like activities, and an inhibitory concentration (IC50) of 3.1 µM for peptidyl-glutamyl peptide hydrolyzing activity [1].

Proteasome-activating peptide 1 TFA is a potent activator of the proteasome, enhancing chymotrypsin-like proteasomal catalytic activity and increasing proteolytic rates both in vitro and in culture. It also inhibits protein aggregation in cellular models of amyotrophic lateral sclerosis (ALS) [1].

Suc-Leu-Leu-Val-Tyr-AMC is a fluorescent substrate for the 20S proteasome, as well as other chymotrypsin-like proteases (20S-proteasome chymotrypsin).

Proteasome-activating peptide 1 enhances chymotrypsin-like proteasomal catalytic activity, boosting proteolytic rates both in vitro and within cultured cells. Additionally, it inhibits protein aggregation in a cellular model of amyotrophic lateral sclerosis [1].