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In enzymology, a dihydrokaempferol 4-reductase () is an enzyme that catalyzes the chemical reaction :cis-3,4-leucopelargonidin + NADP+ (+)-dihydrokaempferol + NADPH + H+ Thus, the two substrates of this enzyme are cis-3,4-leucopelargonidin and NADP+, whereas its 3 products are (+)-dihydrokaempferol, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is cis-3,4-leucopelargonidin:NADP+ 4-oxidoreductase. Other names in common use include dihydroflavanol 4-reductase (DFR), dihydromyricetin reductase, NADPH-dihydromyricetin reductase, and dihydroquercetin reductase. This enzyme participates in flavonoid biosynthesis. == Function == Anthocyanidins, common plant pigments, are further reduced by the enzyme dihydroflavonol 4-reductase (DFR) to the corresponding colorless leucoanthocyanidins. DFR uses dihydromyricetin (ampelopsin) NADPH and 2 H+ to produce leucodelphinidin and NADP.〔(Les cibles d’amélioration pour la qualité des raisins: L’exemple des flavonoïdes, Nancy Terrier (French) )〕 A cDNA for DFR has been cloned from the orchid ''Bromheadia finlaysoniana''.〔The isolation, molecular characterization and expression of dihydroflavonol 4-reductase cDNA in the orchid, ''Bromheadia finlaysoniana''. Chye-Fong Liew, Chiang-Shiong Loh, Chong-Jin Goh and Saw-Hoon Lim, Plant Science, Volume 135, Issue 2, 10 July 1998, Pages 161–169, 〕 Researchers in Japan have genetically manipulated roses by using RNA interference to knock out endogenous DFR, adding a gene DFR from an iris, and adding a gene for the blue pigment, delphinidin, in an effort to create a blue rose, which is being sold worldwide.〔Katsumoto Y et al (2007) Engineering of the Rose Flavonoid Biosynthetic Pathway Successfully Generated Blue-Hued Flowers Accumulating Delphinidin Plant Cell Physiol. 48(11): 1589–1600 ()〕〔Phys.Org website. April 4, 2005 (Plant gene replacement results in the world's only blue rose )〕 Dihydroflavonol 4-reductase is an enzyme part of the lignin biosynthesis pathway. In ''Arabidopsis thaliana'', the enzyme uses sinapaldehyde or coniferyl aldehyde or coumaraldehyde and NADPH to produce sinapyl alcohol or coniferyl alcohol or coumaryl alcohol respectively and NADP+. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Dihydrokaempferol 4-reductase」の詳細全文を読む スポンサード リンク
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