Protease and Phosphatase Inhibitor Cocktail

Mass spectrometry (MS) compatible protease inhibitor cocktail and phosphatase inhibitor cocktail, with broad specificity for the inhibition of:

• Serine, cysteine and aspartic proteases, and metalloproteases
• Tyrosine, serine/threonine, acid and alkaline phosphatases

All inhibitors and fillers were chosen so as not to interfere with LC-MS analyses. Any inhibitors capable of covalent, irreversible protein modification were avoided. This cocktail is EDTA-free. All inhibitors were selected to allow facile downstream sample processing, such as immobilized metal affinity chromatography (IMAC) for His-tagged protein purification and, uniquely, phosphopeptide enrichment.

MS-SAFE Protease and Phosphatase Inhibitor has been used to measure ribosomal protein S6 kinase (S6K) activity.

Tested in mammalian cell lysates and liver tissue extracts. Designed for use in samples to be analyzed by mass spectrometry.

Protease inhibitors: serine, cysteine and aspartic proteases, and metalloproteases
Phosphatase inhibitors: tyrosine, serine/threonine, acid and alkaline phosphatases

Comprehensive protease and phosphatase inhibitor cocktail for mass spectrometry analysis

Compatible with downstream sample processing such as His-tagged protein purification and phosphopeptide enrichment

Allows accurate measurement of protein activity and identification of phosphorylation sites.

Lyophilized powder that is water-soluble

One vial makes 20 mL of 1× inhibitor cocktail working solution, using either water or extraction/lysis buffer. Alternatively, a 10× concentrated solution may be prepared by adding 2 mL of water or extraction/lysis buffer. This 10× solution may then be diluted 10-fold into extraction/lysis buffer as needed for a 1× working solution.

Protease inhibitors:

• Bestatin hydrochloride
• Leupeptin
• Phosphoramidon disodium salt
• Pepstatin A
• Elastatinal
• Aprotinin
• Nafamostat mesylate
• Antipain

Phosphatase inhibitors

• Okadaic acid
• Sodium fluoride
• Sodium orthovanadate
• Bromotetramisole oxalate

Fillers

• β-lactose
• DL-leucine