3IER

Firefly luciferase apo structure (P41 form) with PEG 400 bound

3IER の概要

• エントリーDOI: 10.2210/pdb3ier/pdb
• 関連するPDBエントリー: 3IEP 3IES
• 分子名称: Luciferin 4-monooxygenase, TETRAETHYLENE GLYCOL (3 entities in total)
• 機能のキーワード: oxidoreductase, monooxygenase, photoprotein, luminescence, atp-binding, magnesium, metal-binding, nucleotide-binding, peroxisome
• 由来する生物種: Photinus pyralis (North American firefly)
• 細胞内の位置: Peroxisome : P08659
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 61112.31

構造登録者

Lovell, S.,Battaile, K.P.,Auld, D.S.,Thorne, N.,Lea, W.A.,Maloney, D.J.,Shen, M.,Raj, G.,Thomas, C.J.,Simeonov, A.,Hanzlik, R.P.,Inglese, J. (登録日: 2009-07-23, 公開日: 2010-02-16, 最終更新日: 2023-09-06)

主引用文献

Auld, D.S.,Lovell, S.,Thorne, N.,Lea, W.A.,Maloney, D.J.,Shen, M.,Rai, G.,Battaile, K.P.,Thomas, C.J.,Simeonov, A.,Hanzlik, R.P.,Inglese, J.
Molecular basis for the high-affinity binding and stabilization of firefly luciferase by PTC124.
Proc.Natl.Acad.Sci.USA, 107:4878-4883, 2010

PubMed Abstract: Firefly luciferase (FLuc), an ATP-dependent bioluminescent reporter enzyme, is broadly used in chemical biology and drug discovery assays. PTC124 (Ataluren; (3-[5-(2-fluorophenyl)-1,2,4-oxadiazol-3-yl]benzoic acid) discovered in an FLuc-based assay targeting nonsense codon suppression, is an unusually potent FLuc-inhibitor. Paradoxically, PTC124 and related analogs increase cellular FLuc activity levels by posttranslational stabilization. In this study, we show that FLuc inhibition and stabilization is the result of an inhibitory product formed during the FLuc-catalyzed reaction between its natural substrate, ATP, and PTC124. A 2.0 A cocrystal structure revealed the inhibitor to be the acyl-AMP mixed-anhydride adduct PTC124-AMP, which was subsequently synthesized and shown to be a high-affinity multisubstrate adduct inhibitor (MAI; K(D) = 120 pM) of FLuc. Biochemical assays, liquid chromatography/mass spectrometry, and near-attack conformer modeling demonstrate that formation of this novel MAI is absolutely dependent upon the precise positioning and reactivity of a key meta-carboxylate of PTC124 within the FLuc active site. We also demonstrate that the inhibitory activity of PTC124-AMP is relieved by free coenzyme A, a component present at high concentrations in luciferase detection reagents used for cell-based assays. This explains why PTC124 can appear to increase, instead of inhibit, FLuc activity in cell-based reporter gene assays. To our knowledge, this is an unusual example in which the "off-target" effect of a small molecule is mediated by an MAI mechanism.

PubMed: 20194791
DOI: 10.1073/pnas.0909141107

実験手法

X-RAY DIFFRACTION (2.05 Å)