8B7U

Bacterial chalcone isomerase H33A with taxifolin

8B7U の概要

• エントリーDOI: 10.2210/pdb8b7u/pdb
• 関連するPDBエントリー: 4D06
• 分子名称: Chalcone isomerase, (2R,3R)-2-(3,4-DIHYDROXYPHENYL)-3,5,7-TRIHYDROXY-2,3-DIHYDRO-4H-CHROMEN-4-ONE, CHLORIDE ION, ... (7 entities in total)
• 機能のキーワード: isomerase, bacterial chalcone isomerase, flavonoids, taxifoline
• 由来する生物種: Eubacterium ramulus
• タンパク質・核酸の鎖数: 18
• 化学式量合計: 597977.89

構造登録者

Hinrichs, W.,Palm, G.J. (登録日: 2022-10-03, 公開日: 2022-11-23, 最終更新日: 2024-01-31)

主引用文献

Palm, G.J.,Thomsen, M.,Berndt, L.,Hinrichs, W.
Structural Basis for (2 R ,3 R )-Taxifolin Binding and Reaction Products to the Bacterial Chalcone Isomerase of Eubacterium ramulus .
Molecules, 27:-, 2022

PubMed Abstract: The bacterial chalcone isomerase (CHI) from catalyses the first step in a flavanone-degradation pathway by a reverse Michael addition. The overall fold and the constitution of the active site of the enzyme completely differ from the well-characterised chalcone isomerase of plants. For (+)-taxifolin, CHI catalyses the intramolecular ring contraction to alphitonin. In this study, Fwe perform crystal structure analyses of CHI and its active site mutant His33Ala in the presence of the substrate taxifolin at 2.15 and 2.8 Å resolution, respectively. The inactive enzyme binds the substrate (+)-taxifolin as well defined, whereas the electron density maps of the native CHI show a superposition of substrate, product alphitonin, and most probably also the reaction intermediate taxifolin chalcone. Evidently, His33 mediates the stereospecific acid-base reaction by abstracting a proton from the flavonoid scaffold. The stereospecificity of the product is discussed.

PubMed: 36432010
DOI: 10.3390/molecules27227909

実験手法

X-RAY DIFFRACTION (2.8 Å)