-Ureidopropionic Acid

-Ureidopropionic acid is an intermediate in pyrimidine nucleotide catabolism. Nucleoside phosphorylases act, as shown here to yield a base and ribose-1-phosphate. If bases or nucleosides are not reused for nucleic acid synthesis via salvage pathways, the bases are further degraded to uric acid (purines) or -ureidopropionate (pyrimidines).

1. Dihydrouracil + H2O <=> -Ureidopropionic Acid (catalyzed by Hydropyrimidine Hydratase)

2. -Ureidopropionic Acid + H2O <=> Alanine +  NH4+ + CO2 (catalyzed by -Ureidopropionase)


See also: Figure 22.11, Pyrimidine Catabolism


INTERNET LINK: Pyrimidine Metabolism