A. What amino acid residue(s) do you expect to control the pH-activity profile of the enzyme?

B. Indole is a competitive inhibitor of subtilisin with Ki of 0.05M. what is Vmax for the substrate mentioned above in the presence of 6.25 mM indole, if enzyme concentration is 14.5 micro M?

C. What is the enzymatic reaction rate in the presence of 1.0 M indole if the substrate concentration is 0.25M and all the other conditions are the same in B?

D. If you wish to design an inhibitor of subtilisin more potent than indole, how will you do that?

E. Is the reaction of subtilisin with N-acetyle-L-tyrosine ethyl ester diffusion-controlled? explain your answer.