47. Which one of the following reactions is NOT catalyzed by an epimerase? (A) Ribulose 5-phosphate ↔ Xylulose 5-phosphate (B) UDP-Gal → UDPGIc (C) N-Acetyl-glucosamine 6-phosphate → N-Acetyl-mannosamine 6-phosphate (D) Glucose 1-phosphate ↔ Glucose 6-phosphate (E) All are catalyzed by an epimerase.