4F30

Structure of RPE65: P6522 crystal form grown in ammonium phosphate solution

4F30 の概要

• エントリーDOI: 10.2210/pdb4f30/pdb
• 関連するPDBエントリー: 3FSN 4F2Z 4F3A 4F3D
• 分子名称: Retinoid isomerohydrolase, FE (II) ION, PHOSPHATE ION (3 entities in total)
• 機能のキーワード: monotopic membrane protein, metalloprotein, non-heme iron protein, beta-propeller, smooth er membranes, isomerase, hydrolase
• 由来する生物種: Bos taurus (bovine)
• 細胞内の位置: Cytoplasm: Q28175
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 61191.01

構造登録者

Kiser, P.D.,Palczewski, K. (登録日: 2012-05-08, 公開日: 2012-10-03, 最終更新日: 2023-09-13)

主引用文献

Kiser, P.D.,Farquhar, E.R.,Shi, W.,Sui, X.,Chance, M.R.,Palczewski, K.
Structure of RPE65 isomerase in a lipidic matrix reveals roles for phospholipids and iron in catalysis.
Proc.Natl.Acad.Sci.USA, 109:E2747-E2756, 2012

PubMed Abstract: RPE65 is a key metalloenzyme responsible for maintaining visual function in vertebrates. Despite extensive research on this membrane-bound retinoid isomerase, fundamental questions regarding its enzymology remain unanswered. Here, we report the crystal structure of RPE65 in a membrane-like environment. These crystals, obtained from enzymatically active, nondelipidated protein, displayed an unusual packing arrangement wherein RPE65 is embedded in a lipid-detergent sheet. Structural differences between delipidated and nondelipidated RPE65 uncovered key residues involved in substrate uptake and processing. Complementary iron K-edge X-ray absorption spectroscopy data established that RPE65 as isolated contained a divalent iron center and demonstrated the presence of a tightly bound ligand consistent with a coordinated carboxylate group. These results support the hypothesis that the Lewis acidity of iron could be used to promote ester dissociation and generation of a carbocation intermediate required for retinoid isomerization.

PubMed: 23012475
DOI: 10.1073/pnas.1212025109

実験手法

X-RAY DIFFRACTION (3.15 Å)