A new enzyme, NADPH-dihydropteridine reductase in bovine liver.
An enzyme designated as NADPH-dihydropteridine reductase was found in the extract of bovine liver and partially purified. In contrast to NADH-dpendent dihydropteridine reductase [EC 1.6.99.7], the enzyme catalyzes the reduction of quinonid-dihydropterin to tetrahydropterin in the presence of NADPH. The two enzymes were separated by column chromatography on DEAE-sephadex. Tyrosine formation in the phenylalanine hydroxylation system was also stimulated by NADPH-dihydropteridine reductase. The existence of these two dihydropteridine reductases suggests that the tetrahydro from ofpteridine cofactor may be regenerated in two different ways in vivo.
D000818:Animals; D002417:Cattle; D004093:Dihydropteridine Reductase / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008970:Molecular Weight; D009243:NAD; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D009249:NADP
D009243:NAD; D009249:NADP; D004093:Dihydropteridine Reductase; D009247:NADH, NADPH Oxidoreductases