Dihydropyrimidine dehydrogenase (NADP+)
In enzymology, a dihydropyrimidine dehydrogenase is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are 5,6-dihydrouracil and NADP+, whereas its 3 products are uracil, NADPH, and H+.
In humans the enzyme is encoded by the DPYD gene. It is the initial and rate-limiting step in pyrimidine catabolism. It catalyzes the reduction of uracil and thymine. It is also involved in the degradation of the chemotherapeutic drugs 5-fluorouracil and tegafur.. It also participates in beta-alanine metabolism and pantothenate and coa biosynthesis.Terminology
The systematic name of this enzyme class is 5,6-dihydrouracil:NADP+ 5-oxidoreductase.
Other names in common use include:
- dihydrothymine dehydrogenase
- dihydrouracil dehydrogenase
- 4,5-dihydrothymine: oxidoreductase
- DPD
- DHPDH
- dehydrogenase, dihydrouracil
- DHU dehydrogenase
- hydropyrimidine dehydrogenase
- dihydropyrimidine dehydrogenase
As of late 2007, 5 structures have been solved for this class of enzymes, with PDB accession codes,,,, and.Function
The protein is a pyrimidine catabolic enzyme and the initial and rate-limiting factor in the pathway of uracil and thymidine catabolism. Genetic deficiency of this enzyme results in an error in pyrimidine metabolism associated with thymine-uraciluria and an increased risk of toxicity in cancer patients receiving 5-fluorouracil chemotherapy.Interactive pathway map
