<P> Chymotrypsin is synthesized in the pancreas by protein biosynthesis as a precursor called chymotrypsinogen that is enzymatically inactive . Trypsin activates chymotrypsinogen by cleaving peptidic bonds in positions Arg15 - Ile16 and produces π - Chymotrypsin . In turn , aminic group ( - NH3 ) of the Ile16 residue interacts with the side chain of Glu194 , producing the `` oxyanion hole '' and the hydrophobic `` S1 pocket '' . Moreover , Chymotrypsin induces its own activation by cleaving in positions 14 - 15 , 146 - 147 and 148 - 149 , producing α - Chymotrypsin ( which is more active and stable than π - Chymotrypsin ) . The resulting molecule is a three - polypeptide molecule interconnected via disulfide bonds . </P>
where does cleavage of the peptide bond by chymotrypsin occur
positions 14 - 15 , 146 - 147 and 148 - 149