Purine nucleotides are degraded by a pathway in which they lose their phosphate through the action of 5′-nucleotidase.
B.
Adenylate yields adenosine, which is deaminated to inosine by adenosine deaminase, and inosine is hydrolyzed to hypoxanthine (its purine base) and D-ribose.
C.
Hypoxanthine is oxidized successively to xanthine and then uric acid by xanthine oxidase, a flavoenzyme with an atom of molybdenum and four iron-sulfur centers in its prosthetic group.
D.
Molecular oxygen is the electron acceptor in this complex reaction.