Trypsin is a serine endopeptidase that specifically cleaves peptide bonds on the carboxy side of s-aminoethyl cysteine, arginine and lysine residues and typically there is little or no cleavage at arginyl-proline and lysyl-proline bonds. The distribution of these residues in proteins allows trypsin digestion to produce peptides that are readily identified by mass spectrometry.

• Modified by methylation and TPCK treatment
• Resistant to autolysis and degradation
• Specific activity >10000 U/mg protein

Native trypsin is prone to autolysis, resulting in pseudotrypsin, which exhibits a broader proteolytic specificity (a chymotrypsin like activity) and trypsin fragments that interfere with sequence analysis. MSG-Trypsin™ is chemically methylated to yield an enzymatically active protein with maximum trypsin specificity and is extremely resistant to autolysis. In addition, the modified trypsin is TPCK treated to inactive the interfering chymotrypsin activity and the resulting protein is affinity purified and lyophilised. The resulting trypsin is extremely resistant to autolysis and has a specific activity over 10000 units/mg protein. The maximum activity is in the pH range of 7 to 9 and the activity is reversibly inactivated at pH 4.