Papain from Carica papaya

Leupeptin works as peptide antibiotic that has been isolated from different Streptomyces species. It is a reversible inhibitor of serine and cysteine proteases, eg. Plasmin, Trypsin, Papain, Cathepsin B and Thrombin. It does not inhibit pepsin, cathepsin A and D. The working concentration is 10-100µM (5 - 50µg/mL). Leupeptin is soluble in water. A 1mg/mL stock solution can be stored at -20°C for 6 months. Umezawa, H. (1976) Methods Enzymol. 45 (Part B), 678-695. Brass, L.F. & Smith, S.J. (1988) J. Biol. Chem. 263, 5210-5216. You will find further protease inhibitors here: Inhibitors >: Pepstatin A >, AEBSF >, Leupeptin >, TLCK >, or Bestatine >.

E-64 is an irreversible inhibitor of different cysteine proteases (papain, bromelain, ficin, cathepsin B, H and L, tumor-cathepsin, calpain, V-CATH from Autographa californica M nucleopolyhedro virus (AcMNPV) and Streptococcus-protease). All enzymes are completely inhibited by a concentration of 10 - 30 μM within 30 minutes. E-64 and other protease inhibitors (e. g. diisopropylfluorophosphate and PMSF) are able to inhibit the programmed cell death, that is induced by activation of the T cell receptor in different cell lines of the immune system, not by blocking the signal transduction. The effect of dexamethason, which induces apoptosis as an antagonist of the T cell receptor, is enhanced. If proteins are expressed in the baculo virus system with a functional v-cath gene, very often a proteolytic activity can be observed. This reduces the quality of the expressed protein significantly. The addition of E-64 to all reaction steps avoids the degradation almost completely. Stability: E-64 is stable against reducing agents. Stock solutions have concentrations between 1mM and 10mM in DMSO or 50% ethanol and are stable for several days, if stored at +4°C. Aliquots may be stored at -20°C for approx. one month. Synonyme: trans-Epoxysuccinyl-L-leucylamido(4-guanidino)butan; L-trans-3-Carboxyoxiran-2-carbonyl-L-leucylagmatin; N-(trans-Epoxysuccinyl)-L-leucin-4-guanidinobutylamid You will find further protease inhibitors here: Inhibitors >: Pepstatin A >, AEBSF >, Leupeptin >, TLCK >, PMSF >, Bestatine > or Diisopropylphosphorofluoridat (DFP) >.