抄録
Dihydropyrimidine dehydrogenase (DPD) is the first and rate-limiting enzyme of the pyrimidine reductive pathway in mammals and plants, and catalyzes the NADPH-dependent reduction of pyrimidines to 5,6-dihydropyrimidines. Although DPD homologs occur in many bacteria, their functions have not been clarified. We purified and characterized novel NADH-dependent DPD, PreT-PreA, from Escherichia coli K12 and NADPH-dependent DPD, PydX-PydA, from Pseudomonas putida. Biochemical and genetic studies revealed that PydX-PydA is the first enzyme of the pyrimidine reductive pathway in P. putida, but PreT-PreA is not involved in the reductive pathway in E. coli, suggesting PreT-PreA represents a novel class of DPDs.
