Protease Inhibitors

Antipain
Stock 12.5 mg/mL

Working 12.5 ug/mL

''A reversible cysteine and serine protease inhibitor of trypsin, papain and cathepsin A and B. Slightly inhibits plasmin. More specific than leupeptin for papain and trypsin.''

'' Soluble in MeOH, water, and DMSO; less soluble in ethanol or acetonitrile. ''

Method

 * Antipain powder (5 mg in bottle)
 * ddH2O

Method (makes 400 uL of stock solution)

 * 1) Add 400 uL of ddH2O to the 5 mg bottle of antipain.
 * 2) Mix well and aliquot 20 uL into microcentrifuge tubes.
 * 3) Cover with aluminum foil and store at -20 °C. Stock solutions of 10 mM can be stored at -20°C for up to 9 months. Protect from light.

Chymostatin
Stock 10 mg/mL

Working 10 ug/mL

''Chymostatin is a strong inhibitor of many proteases, including chymotrypsin, chymotrypsin-like serine proteinases and several cysteine proteases (including papain). Chymostatin is a mixture of several components, typically ~70% chymostatin A, ~20% chymostatin B and 5-10% chymostatin C.''



''Soluble in DMSO. Partially soluble in H2O.''

Material

 * Chymostatin powder (5 mg in bottle)


 * DMSO (100%)

Method (makes 500 uL of stock solution)

 * 1) Add 500 uL of DMSO to the 5 mg bottle of chymostatin.
 * 2) Mix well and aliquot 20 uL into labeled microcentrifuge tubes.
 * 3) Store stock aliquots at -20 C. Stable for several months when stored in aliquots at -20 C.

E-64
Stock 10 mg/mL

Working 10 ug/mL

''E-64 is an irreversible, potent, and highly selective cysteine protease inhibitor. Interacts with the Sn subsites of proteases. Has no action on cysteine residues in other proteins. E-64 is also soluble in DMSO, a 10 mM solution can be prepared and stored at -20 C.''

Material

 * E-64 powder (5 mg in bottle)


 * ddH2O or DMSO (100%)

Method (makes 500 uL of stock solution)

 * 1) Add 500 ul of ddH2O or DMSO to the 5 mg bottle of E-64.
 * 2) Mix well and aliquot 30 uL into microcentrifuge tubes.
 * 3) Store at -20 C. Stock solutions are stable for 3-4 months at -20 C. Diluted solutions are stable for days at neutral pH.

Leupeptin
Stock 5 mg/mL

Working 5 ug/mL

''Leupeptin is an organic compound produced by actinomycetes, serine and cysteine proteases reversibly. Inhibits trypsin-like proteases and some cysteine proteases including endoproteinase Lys-C, Kallikrein, papain, thrombin, cathepsin B and trypsin.''

Materials

 * Leupeptin powder (5 mg in bottle)


 * ddH2O

Method (makes 1 mL of stock solution)

 * 1) Add 1 mL of ddH2O to the 5 mg bottle of leupeptin.
 * 2) Mix well and aliquot 20 uL into microcentrifuge tubes.
 * 3) Store at -20 C.  Stable for several hours in water. Stock solutions in water are stable for 1 week at 4 C and 6 months at -20 C. Avoid repeated thaw freeze cycles. 