8U06

Imine reductase RedE bound with NADP+ and arcyriaflavin A (primary site)

8U06 の概要

• エントリーDOI: 10.2210/pdb8u06/pdb
• 分子名称: RedE, NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE, Arcyriaflavin A, ... (8 entities in total)
• 機能のキーワード: indolocarbazole, imine reductase, nadph-dependent, biosynthetic protein
• 由来する生物種: uncultured bacterium
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 69810.78

構造登録者

Daniel-Ivad, P.,Ryan, K.S. (登録日: 2023-08-28, 公開日: 2024-09-04, 最終更新日: 2025-03-05)

主引用文献

Daniel-Ivad, P.,Ryan, K.S.
An imine reductase that captures reactive intermediates in the biosynthesis of the indolocarbazole reductasporine.
J.Biol.Chem., 300:105642-105642, 2024

PubMed Abstract: Imine reductases (IREDs) and reductive aminases have been used in the synthesis of chiral amine products for drug manufacturing; however, little is known about their biological contexts. Here we employ structural studies and site-directed mutagenesis to interrogate the mechanism of the IRED RedE from the biosynthetic pathway to the indolocarbazole natural product reductasporine. Cocrystal structures with the substrate-mimic arcyriaflavin A reveal an extended active site cleft capable of binding two indolocarbazole molecules. Site-directed mutagenesis of a conserved aspartate in the primary binding site reveals a new role for this residue in anchoring the substrate above the NADPH cofactor. Variants targeting the secondary binding site greatly reduce catalytic efficiency, while accumulating oxidized side-products. As indolocarbazole biosynthetic intermediates are susceptible to spontaneous oxidation, we propose the secondary site acts to protect against autooxidation, and the primary site drives catalysis through precise substrate orientation and desolvation effects. The structure of RedE with its extended active site can be the starting point as a new scaffold for engineering IREDs and reductive aminases to intercept large substrates relevant to industrial applications.

PubMed: 38199566
DOI: 10.1016/j.jbc.2024.105642

実験手法

X-RAY DIFFRACTION (1.6 Å)