Using site specific mutagenesis to change residues in the substrate binding cleft of PKA (not residues involved in catalytic roles), how would you alter PKAâs substrate specifity? By this, I mean how would you specifically make mutations in the PKA enzyme amino acid sequence (not the substrate sequence) that would alter amino acid preferences for particular residues on a substrate peptide that you might want to design for this enzyme. Please think carefully about what this means. It does not mean changing ATP binding or altering the active site base or Mg binding site, as such mutations would only decrease overall catalytic activity of the phosphotransfer reaction. Please provide three detailed examples of how you could try to modify the substrate specificity of PKA (assuming that protein sequences exist in the cell that would match the newly designed substrate specificity of the enzyme).
Using site specific mutagenesis to change residues in the substrate binding cleft of PKA (not residues involved in catalytic roles), how would you alter PKAâs substrate specifity? By this, I mean how would you specifically make mutations in the PKA enzyme amino acid sequence (not the substrate sequence) that would alter amino acid preferences for particular residues on a substrate peptide that you might want to design for this enzyme. Please think carefully about what this means. It does not mean changing ATP binding or altering the active site base or Mg binding site, as such mutations would only decrease overall catalytic activity of the phosphotransfer reaction. Please provide three detailed examples of how you could try to modify the substrate specificity of PKA (assuming that protein sequences exist in the cell that would match the newly designed substrate specificity of the enzyme).
