Applications of Zymography (Substrate-SDS-PAGE) for Peptidase Screening in a Post-Genomic Era

Peptidases are enzymes that catalyze the hydrolysis of peptide bonds in proteins or peptides. The hydrolysis can be specific or unspecific, leading to highly regulated cleavage of specific peptide bonds, or to complete degradation of proteins to oligopeptides and/or amino acids. Peptidases can be classified as endoor exopeptidases, the latter only act near the ends of the polypeptide chain. Endopeptidases are divided into six major families by virtue of the specific chemistry of their active site: aspartic, serine, metallo-, cysteine, glutamic and threonine peptidases (Rawlings et al. 2010).