Reaction: 5,6,7,8-tetrahydrobiopterin + 2 NADP+ = biopterin + 2 NADPH + 2 H+
Other name(s): PTR1; pteridine reductase 1
Systematic name: 5,6,7,8-tetrahydrobiopterin:NADP+ oxidoreductase
Comments: The enzyme from Leishmania (both amastigote and promastigote forms) catalyses the reduction by NADPH of folate and a wide variety of unconjugated pterins, including biopterin, to their tetrahydro forms. It also catalyses the reduction of 7,8-dihydropterins and 7,8-dihydrofolate to their tetrahydro forms. In contrast to EC 22.214.171.124 (dihydrofolate reductase) and EC 126.96.36.199 (6,7-dihydropteridine reductase), pteridine reductase will not catalyse the reduction of the quinonoid form of dihydrobiopterin. The enzyme is specific for NADPH; no activity has been detected with NADH. It also differs from EC 188.8.131.52 (dihydrofolate reductase) in being specific for the B side of NADPH.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 131384-61-7
1. Nare, B., Hardy, L. and Beverley, S.M. The roles of pteridine reductase 1 and dihydrofolate reductase-thymidylate synthase in pteridine metabolism in the protozoan parasite Leishmania major. J. Biol. Chem. 272 (1997) 13883-13891. [PMID: 9153248]
2. Gourley, D.G., Schüttelkopf, A.W., Leonard, G.A., Luba, J., Hardy, L.W., Beverley, S.M. and Hunter, W.N. Pteridine reductase mechanism correlates pterin metabolism with drug resistance in trypanosomatid parasites. Nat. Struct. Biol. 8 (2001) 521-525. [PMID: 11373620]
3. Fitzpatrick, P.F. The aromatic amino acid hydroxylases. Adv. Enzymol. Relat. Areas Mol. Biol. 74 (2000) 235-294. [PMID: 10800597]