. "Cytosolic APRT dimer catalyzes the reaction of adenine and 5-phospho-alpha-D-ribose 1-diphosphate to form AMP and pyrophosphate (Holden et al. 1979)."^^ . . . . . . "Adenine + PRPP => AMP + PPi"^^ . "2.4.2.7"^^ . . . . .