PMID: 11179210 , Related PDB ids: 1B0P, 1E1L, 1F6M, 1FUM, 1GRA, 1H7W, 1H7X, 2DOR

Authors:

Dobritzsch D, Schneider G, Schnackerz KD, Lindqvist Y

Title:

Crystal structure of dihydropyrimidine dehydrogenase, a major determinant of the pharmacokinetics of the anti-cancer drug 5-fluorouracil.

Journal:

EMBO J. 2001 Feb 15;20(4):650-60.

Abstract:

Dihydropyrimidine dehydrogenase catalyzes the first step in pyrimidine degradation: the NADPH-dependent reduction of uracil and thymine to the corresponding 5,6-dihydropyrimidines. Its controlled inhibition has become an adjunct target for cancer therapy, since the enzyme is also responsible for the rapid breakdown of the chemotherapeutic drug 5-fluorouracil. The crystal structure of the homodimeric pig liver enzyme (2x 111 kDa) determined at 1.9 A resolution reveals a highly modular subunit organization, consisting of five domains with different folds. Dihydropyrimidine dehydrogenase contains two FAD, two FMN and eight [4Fe-4S] clusters, arranged in two electron transfer chains that pass the dimer interface twice. Two of the Fe-S clusters show a hitherto unobserved coordination involving a glutamine residue. The ternary complex of an inactive mutant of the enzyme with bound NADPH and 5-fluorouracil reveals the architecture of the substrate-binding sites and residues responsible for recognition and binding of the drug.