Protein Mass Spectrometry

Protease Profiler

Select the best protease for protein analysis!

Proteolysis and characterization of the digest peptides for identification, confirmation or deduction by mass spectrometry is a staple tool in proteomics. Proteases with cleavage sites of high specificity have the ability to generate predictable, consistent digest peptides, simplifying interpretation of mass spectra. Trypsin generates peptides in the useful mass range for mass spectrometry and is recognized as the most commonly used protease for protein identification. However, in instances where the trypsin may cleave at an active site or other feature of interest, a substitute protease may be the optimal choice.

The Protease Profiler Kit (PP0500) provides four proven alternative proteases in addition to Proteomics Grade Trypsin, an enzyme solubilization reagent and enzyme reaction buffer, all in a single convenient package. The kit allows flexibility to enable optimized digestion of target proteins with a variety of pre-qualified proteases.

Enzyme Specificity Optimal pH Average MW
Trypsin, Proteomics Grade Carboxyl side of Arg and Lys pH 8.0 23.3 kDa
Asp-N Amine side of Asp and Cys pH 6.0 - 8.5 24.5 kDa
Glu-C Carboxyl side of Glu and Asp pH 4.0 - 7.8 29.0 kDa
Lys-C Carboxyl side of Lys pH 8.5 28.0 kDa
Arg-C Carboxyl side of Arg pH 7.5 - 8.5 26.5 kDa

The Protease Profiler Kit is used for:

  • Characterization of protein structure. Explore the primary structure of your protein of interest through digestion with enzymes of distinct specificities.
  • Double Enzymatic Digestion. An initial digestion may result in peptide fragments greater than 5,000 Daltons, often beyond the optimum detection range for most MS systems/instruments. A second digestion using a protease with different specificity results in cleavage of the large peptides, generating smaller peptides suitable for MS.
  • Exploration of alternative proteases. Trypsin may be incompatible with some protein samples; find the protease best suited to your protein of interest and improve the quality of your data.
  • In-Solution or In-gel Digestion. Optimized protocols and reagents for both digest conditions are provided, enabling flexibility in your analysis.



  Proteomics Grade Trypsin
Asp-N Protease
Glu-C Protease
Lys-C Protease
Arg-C Protease
Enzyme Solubilization Reagent
Enzyme Reaction Buffer
  20 µg
2 µg
25 µg
5 µg
5 µg
1 mL
25 mL

Explore alternative proteases. Each enzyme creates a distinct peptide map; choose the digest that best allows you to characterize your protein of interest.

Product Code Product Name Size
PP0500 Protease Profiler Kit 1 kit

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