Eenzyme trypsin recognizes Lys and Arg residues, and has substrate specificity pocket as shown. It has a Asp residue at the bottom of hydrophobic pocket. A mutation of Asp-189 to Ala-189 Asp 189 Changes the substrate specificity to Asp Changes the substrate specificity to Ala Changes the substrate specificity to Arg Does not change the substrate specificity None of the above