Thermo Scientific Halt Phosphatase Inhibitor Cocktail preserves the phosphorylation state of proteins during and after cell lysis or tissue protein extraction.
The Halt Phosphatase Inhibitor Cocktail protects phosphoproteins from serine/threonine phosphatases as well as protein tyrosine phosphatases (PTPs) during cell lysis. The cocktail contains a mixture of four inhibitors of broad specificity, including sodium fluoride, sodium orthovanadate, sodium pyrophosphate and beta-glycerophosphate. Conveniently packaged in a 100X format, the cocktail is stable at 4°C and is suitable for use with any cell or tissue extract. The cocktail preserves protein phosphorylation in immunoprecipitation and kinase assays. Furthermore, the cocktail is compatible with popular protein assays such as the Thermo Scientific Pierce BCA Protein Assay Kit (Part No. 23225) and Bradford-based Pierce Coomassie Plus Assay Kit (Part No. 23236).
- All-in-one format – inhibits both serine-threonine phosphatases and protein tyrosine phosphatases
- Compatible – works with standard protein assays, including BCA and coomassie (Bradford) assays
- Convenient storage – refrigerator (2 to 8°C) storage saves valuable space in the freezer and provides for immediate use
- Multiple sizes – select a package size of the 100X cocktail that is ideal for any particular scale and workflow of protein extraction experiment
Preserved phosphorylation states of three proteins in cell lysate. HeLa cells were lysed in the absence (-) and presence (+) of a 1X concentration of the Thermo Scientific Halt Phosphatase Inhibitor Cocktail. Cell lysates were analyzed by Western blot for total and phosphorylated protein as indicated.
Panel A: MEK and phosphorylated MEK (PMEK).
Panel B: MAP Kinase and PMAP Kinase.
Panel C: STAT3 and PSTAT3.
The proteins are phosphorylated on serine, threonine/tyrosine and tyrosine, respectively.
Phosphorylation and dephosphorylation comprise a molecular on/off switch that regulates many key biological pathways within the cell, including signal transduction, cell division and apoptosis. To effectively study phosphorylation activation states, one must inactivate phosphatases to prevent their uncontrolled activity upon cell lysis. Halt Phosphatase Inhibitor Cocktail accomplishes this task.
The Halt Phosphatase Inhibitor Cocktail does not contain protease inhibitors. If necessary, protease inhibitors can be added along with the phosphatase inhibitor cocktail. Halt Phosphatase Inhibitor Cocktail is compatible with most detergent-based cell lysis reagents, including Thermo Scientific Pierce Cell Lysis Solutions. The cocktail is not directly compatible with 2D gel electrophoresis or immobilized metal chelate affinity chromatography. However, the components can be removed by dialysis or desalting before performing these incompatible procedures.
Halt Phosphatase Inhibitor is...
- Devoid of protease inhibitors. To protect against both proteases and phosphatases, use Halt Protease and Phosphatase Inhibitor Cocktail.
- Not compatible with immobilized metal chelate affinity chromatography (IMAC) and 2-D gel electrophoresis. Either dialyze or desalt sample to effectively remove inhibitors from cell extracts before performing such procedures.
- Supplied as a 100X concentrate that is effective when used at a final concentration of 1X; however, samples that contain particularly high levels of phosphatase activity may require a final concentration of 2-3X.
- Compatible with all Pierce Cell Lysis Solutions.
Review of Protease and Phosphatase Inhibitors
Cell Lysis Handbook
Mass Spec Sample Preparation Handbook
All Protease and Phosphatase Inhibitor Cocktails and Tablets
Pierce Cell Lysis Solutions