5U8X

Crystal structure of Fe-CAO1

5U8X の概要

• エントリーDOI: 10.2210/pdb5u8x/pdb
• 関連するPDBエントリー: 5U8Y
• 分子名称: Carotenoid oxygenase 1, FE (II) ION, CHLORIDE ION, ... (5 entities in total)
• 機能のキーワード: beta propeller, dioxygenase, resveratrol, carotenoid oxygenase, oxidoreductase
• 由来する生物種: Neurospora crassa OR74A
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 238723.29

構造登録者

Sui, X.,Palczewski, K.,Banerjee, S.,Kiser, P.D. (登録日: 2016-12-15, 公開日: 2017-05-31, 最終更新日: 2024-07-10)

主引用文献

Sui, X.,Weitz, A.C.,Farquhar, E.R.,Badiee, M.,Banerjee, S.,von Lintig, J.,Tochtrop, G.P.,Palczewski, K.,Hendrich, M.P.,Kiser, P.D.
Structure and Spectroscopy of Alkene-Cleaving Dioxygenases Containing an Atypically Coordinated Non-Heme Iron Center.
Biochemistry, 56:2836-2852, 2017

PubMed Abstract: Carotenoid cleavage oxygenases (CCOs) are non-heme iron enzymes that catalyze scission of alkene groups in carotenoids and stilbenoids to form biologically important products. CCOs possess a rare four-His iron center whose resting-state structure and interaction with substrates are incompletely understood. Here, we address this knowledge gap through a comprehensive structural and spectroscopic study of three phyletically diverse CCOs. The crystal structure of a fungal stilbenoid-cleaving CCO, CAO1, reveals strong similarity between its iron center and those of carotenoid-cleaving CCOs, but with a markedly different substrate-binding cleft. These enzymes all possess a five-coordinate high-spin Fe(II) center with resting-state Fe-His bond lengths of ∼2.15 Å. This ligand set generates an iron environment more electropositive than those of other non-heme iron dioxygenases as observed by Mössbauer isomer shifts. Dioxygen (O) does not coordinate iron in the absence of substrate. Substrates bind away (∼4.7 Å) from the iron and have little impact on its electronic structure, thus excluding coordination-triggered O binding. However, substrate binding does perturb the spectral properties of CCO Fe-NO derivatives, indicating proximate organic substrate and O-binding sites, which might influence Fe-O interactions. Together, these data provide a robust description of the CCO iron center and its interactions with substrates and substrate mimetics that illuminates commonalities as well as subtle and profound structural differences within the CCO family.

PubMed: 28493664
DOI: 10.1021/acs.biochem.7b00251

実験手法

X-RAY DIFFRACTION (2.165 Å)