What are the different types of proteases?

There are many different types of proteases. Some common examples of proteases include trypsin, collagenase, pepsin, chymotrypsin, dipeptidase, carboxypeptidase, elastase, aminopeptidase, thrombin, and insulinase. 

• Trypsin is found in pancreatic juice and breaks down proteins, proteoses, and peptones into dipeptides. 
• Collagenase functions to degrade collagen found in the extracellular matrix. Pepsin exists in the stomach and converts proteins into smaller peptides. 
• Chymotrypsin is a serine protease produced by the pancreas which hydrolyzes the peptide bonds of tryptophan, tyrosine, leucine, and phenylalanine. 
• Elastase is present in pancreatic juice and digests elastin to help digest food. 
• Dipeptidase is found in intestinal secretions and breaks dipeptides down into amino acids. 
• Insulinase is found in the liver and kidney, and functions to degrade insulin. 
• Carboxypeptidase hydrolyzes a peptide bond at the C-terminal end of a protein or peptide. 
• Thrombin is a protease that is involved in blood coagulation by converting fibrinogen to fibrin. 
• Aminopeptidases catalyze the cleavage of amino acids from the N-terminus of proteins or peptides. 

Proteolytic enzymes can be divided in two general groups based on the site of peptide bond cleavage. These groups are exopeptidase and endopeptidase. Exopeptidases catalyze the cleavage on terminal peptide bonds. Endopeptidases catalyze the cleavage of internal peptide bonds of proteins. Additionally, there are also oligopeptidases, which are enzymes that act on specific peptide bonds (substrates) rather than protein.