BIOC 3560 Lecture Notes - Lecture 10: Serine Protease, Chymotrypsin, Digestive Enzyme

• School: University of Guelph
• Department: Biochemistry
• Course: BIOC 3560
• Professor: N/ A

Document Summary

Activated by cleavage of specific peptide bonds (one or more bonds) Conformational changes in the enzyme expose the active site. Activated by trypsin, produces -chymotrypsin --> cuts between arg15 and ile16. Chymotrypsin is the main active digestive enzyme for proteins. Many digestive enzymes are regulated by proteolysis --> prevents internal digestion of cells. Many proteolytic-regulated proteases are serine proteases --> active site contains serine. Enzymatic activity of chymotrypsin and other serine proteases is highly sensitive to ph. Allows his57 to act as a proton acceptor, induces nucleophilic activity in ser195. Allows formation of an ion pair with asp194, stabilizes the active conformation. Conformational changes induced by proteolytic cleavage are not the same as allostery. Both change conformation of the protein, but for different reasons. Formation of a blood clot is highly regulated. Active form of one factor plays an important role in activating the next factor in the sequence. 2 pathways must start to cause a clot.