11.
An enzyme shows highest activity in the pH range 2.0 - 3.0. At pH 4.0 and pH 7.0, the enzyme exhibits 50% and 1%, respectively, of its highest activity. Which of the following states of anamino acid residue in the catalytic site is most responsible for its activity profile?
A:
A protonated Asp
B:
A deprotonated Asp
C:
A deprotonated Asn
D:
A protonated Asn
The answer is:
A
