What role does trypsin play in protein purification protocols?

Trypsin is a proteolytic enzyme that specifically cleaves peptide bonds at the carboxyl side of lysine and arginine residues. In protein purification protocols, this property is utilized to selectively digest proteins into smaller peptides, thereby allowing researchers to analyze specific regions of proteins or to modify proteins in a way that facilitates their purification. By breaking down larger, more complex protein structures, trypsin can help in the identification of specific domains or active sites that may be important for a protein's function.

This selective cleavage can also assist in removing unwanted proteins or contaminants from the sample, making subsequent purification steps more effective. Using trypsin at the correct concentration and under controlled conditions ensures that the desired proteins are retained while non-essential components are removed, thus enhancing the overall efficiency of the purification process.