1EYQ

Chalcone isomerase and naringenin

1EYQ の概要

• エントリーDOI: 10.2210/pdb1eyq/pdb
• 関連するPDBエントリー: 1EYP
• 分子名称: CHALCONE-FLAVONONE ISOMERASE 1, SULFATE ION, NARINGENIN, ... (4 entities in total)
• 機能のキーワード: chalcone isomerase, flavonoid, isomerase
• 由来する生物種: Medicago sativa
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 48727.29

構造登録者

Jez, J.M.,Bowman, M.E.,Dixon, R.A.,Noel, J.P. (登録日: 2000-05-08, 公開日: 2000-09-06, 最終更新日: 2024-02-07)

主引用文献

Jez, J.M.,Bowman, M.E.,Dixon, R.A.,Noel, J.P.
Structure and mechanism of the evolutionarily unique plant enzyme chalcone isomerase.
Nat.Struct.Biol., 7:786-791, 2000

PubMed Abstract: Chalcone isomerase (CHI) catalyzes the intramolecular cyclization of chalcone synthesized by chalcone synthase (CHS) into (2S)-naringenin, an essential compound in the biosynthesis of anthocyanin pigments, inducers of Rhizobium nodulation genes, and antimicrobial phytoalexins. The 1.85 A resolution crystal structure of alfalfa CHI in complex with (2S)-naringenin reveals a novel open-faced beta-sandwich fold. Currently, proteins with homologous primary sequences are found only in higher plants. The topology of the active site cleft defines the stereochemistry of the cyclization reaction. The structure and mutational analysis suggest a mechanism in which shape complementarity of the binding cleft locks the substrate into a constrained conformation that allows the reaction to proceed with a second-order rate constant approaching the diffusion controlled limit. This structure raises questions about the evolutionary history of this structurally unique plant enzyme.

PubMed: 10966651
DOI: 10.1038/79025

実験手法

X-RAY DIFFRACTION (1.85 Å)