8FEU

Flavanone 4-Reductase from Sorghum bicolor-NADP(H) and naringenin complex

8FEU の概要

• エントリーDOI: 10.2210/pdb8feu/pdb
• 分子名称: 3-deoxyanthocyanidin synthase, NARINGENIN, NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE, ... (5 entities in total)
• 機能のキーワード: sdr type protein, flavanone, sorghum, oxidoreductase
• 由来する生物種: Sorghum bicolor (sorghum)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 78101.73

構造登録者

Zhang, B.,Kang, C. (登録日: 2022-12-06, 公開日: 2023-09-20, 最終更新日: 2023-10-11)

主引用文献

Lewis, J.A.,Zhang, B.,Harza, R.,Palmer, N.,Sarath, G.,Sattler, S.E.,Twigg, P.,Vermerris, W.,Kang, C.
Structural Similarities and Overlapping Activities among Dihydroflavonol 4-Reductase, Flavanone 4-Reductase, and Anthocyanidin Reductase Offer Metabolic Flexibility in the Flavonoid Pathway.
Int J Mol Sci, 24:-, 2023

PubMed Abstract: Flavonoids are potent antioxidants that play a role in defense against pathogens, UV-radiation, and the detoxification of reactive oxygen species. Dihydroflavonol 4-reductase (DFR) and flavanone 4-reductase (FNR) reduce dihydroflavonols and flavanones, respectively, using NAD(P)H to produce flavan-(3)-4-(di)ols in flavonoid biosynthesis. Anthocyanidin reductase (ANR) reduces anthocyanidins to flavan-3-ols. In addition to their sequences, the 3D structures of recombinant DFR, FNR and ANR from sorghum and switchgrass showed a high level of similarity. The catalytic mechanism, substrate-specificity and key residues of three reductases were deduced from crystal structures, site-directed mutagenesis, molecular docking, kinetics, and thermodynamic ana-lyses. Although DFR displayed its highest activity against dihydroflavonols, it also showed activity against flavanones and anthocyanidins. It was inhibited by the flavonol quercetin and high concentrations of dihydroflavonols/flavonones. SbFNR1 and SbFNR2 did not show any activity against dihydroflavonols. However, SbFNR1 displayed activity against flavanones and ANR activity against two anthocyanidins, cyanidin and pelargonidin. Therefore, SbFNR1 and SbFNR2 could be specific ANR isozymes without delphinidin activity. Sorghum has high concentrations of 3-deoxyanthocyanidins in vivo, supporting the observed high activity of SbDFR against flavonols. Mining of expression data indicated substantial induction of these three reductase genes in both switchgrass and sorghum in response to biotic stress. Key signature sequences for proper DFR/ANR classification are proposed and could form the basis for future metabolic engineering of flavonoid metabolism.

PubMed: 37762209
DOI: 10.3390/ijms241813901

実験手法

X-RAY DIFFRACTION (2.12 Å)