4OU9

Crystal structure of apocarotenoid oxygenase in the presence of Triton X-100

4OU9 の概要

• エントリーDOI: 10.2210/pdb4ou9/pdb
• 関連するPDBエントリー: 2BIW 4OU8
• 分子名称: Apocarotenoid-15,15'-oxygenase, FE (II) ION, CHLORIDE ION, ... (4 entities in total)
• 機能のキーワード: monotopic membrane protein, non-heme iron, metalloenzyme, 4-his iron center, beta propeller, carotenoid oxygenase, oxidoreductase
• 由来する生物種: Synechocystis sp.
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 217671.05

構造登録者

Sui, X.,Palczewski, K.,Kiser, P.D. (登録日: 2014-02-15, 公開日: 2014-03-19, 最終更新日: 2024-02-28)

主引用文献

Sui, X.,Kiser, P.D.,Che, T.,Carey, P.R.,Golczak, M.,Shi, W.,von Lintig, J.,Palczewski, K.
Analysis of Carotenoid Isomerase Activity in a Prototypical Carotenoid Cleavage Enzyme, Apocarotenoid Oxygenase (ACO).
J.Biol.Chem., 289:12286-12299, 2014

PubMed Abstract: Carotenoid cleavage enzymes (CCEs) constitute a group of evolutionarily related proteins that metabolize a variety of carotenoid and non-carotenoid substrates. Typically, these enzymes utilize a non-heme iron center to oxidatively cleave a carbon-carbon double bond of a carotenoid substrate. Some members also isomerize specific double bonds in their substrates to yield cis-apocarotenoid products. The apocarotenoid oxygenase from Synechocystis has been hypothesized to represent one such member of this latter category of CCEs. Here, we developed a novel expression and purification protocol that enabled production of soluble, native ACO in quantities sufficient for high resolution structural and spectroscopic investigation of its catalytic mechanism. High performance liquid chromatography and Raman spectroscopy revealed that ACO exclusively formed all-trans products. We also found that linear polyoxyethylene detergents previously used for ACO crystallization strongly inhibited the apocarotenoid oxygenase activity of the enzyme. We crystallized the native enzyme in the absence of apocarotenoid substrate and found electron density in the active site that was similar in appearance to the density previously attributed to a di-cis-apocarotenoid intermediate. Our results clearly demonstrated that ACO is in fact a non-isomerizing member of the CCE family. These results indicate that careful selection of detergent is critical for the success of structural studies aimed at elucidating structures of CCE-carotenoid/retinoid complexes.

PubMed: 24648526
DOI: 10.1074/jbc.M114.552836

実験手法

X-RAY DIFFRACTION (2 Å)