Protection from Endogenous Proteases During Protein Extraction
The process of breaking open cell walls and subcellular compartments during protein extraction liberates endogenous proteases. Without effective inhibition, these enzymes will quickly diminish yields of intact proteins from cell and tissue extracts. The addition of protease inhibitors to lysis buffers used for protein extractions is an effective means of protecting extracted proteins from enzymatic degradation by endogenous proteases.
Use Proteoloc™ EDTA-free if the next step in your workflow is isoelectric focusing, metal-affinity column separation, or another technique that is incompatible with chelation. Otherwise, use the standard Proteoloc™ Protease Inhibitor Cocktail, which contains EDTA. Both products offer protection against loss of intact proteins due to endogenous protease activity. Proteoloc™ Protease Inhibitor Cocktails are provided as 100X stock solutions in DMSO.
Protease Inhibitor Cocktail Proteloc contains the following protease inhibitors:
- AEBSF: Irreversible serine protease inhibitor. Inhibits chymotrypsin, kallikrein, plasmin, thrombin, and trypsin.
- Aprotinin: Reversible serine protease inhibitor. Inhibits chymotrypsin, kallikrein, plasmin, trypsinogen, and urokinase.
- Bestatin: Metalloprotease inhibitor selective for aminopeptidases. Inhibits activity of leucine aminopeptidase, aminopeptidase B, and triamino peptidase.
- E-64: Irreversible inhibitor of cystine proteases. Inhibits calpain, papain, and cathespin B.
- Leupeptin: Reversible inhibitor of serine and cystine proteases. Inhibits calpain, papain, trypsin, and cathespin B.
- Pepstatin A: Reversible aspartic acid protease inhibitor. Inhibits pepsin, rennin, cathespin D, chymosin, and protease B.
Proteoloc™ Inhibitor Cocktail is the protease inhibitor mixture recommended for use with UPX Universal Protein Extraction Kits.