3TMR

IrisFP, planar chromophore

3TMR の概要

• エントリーDOI: 10.2210/pdb3tmr/pdb
• 関連するPDBエントリー: 1ZUX 2BTJ 2VVH 2VVI 2VVJ 3TMT
• 分子名称: Green to red photoconvertible GPF-like protein EosFP, SULFATE ION, SULFITE ION, ... (4 entities in total)
• 機能のキーワード: beta-can, fluorescent protein
• 由来する生物種: Lobophyllia hemprichii (Lobed brain coral)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 108313.54

構造登録者

Adam, V.,Carpentier, P.,Roy, A.,Field, M.,Bourgeois, D. (登録日: 2011-08-31, 公開日: 2011-11-16, 最終更新日: 2024-11-20)

主引用文献

Roy, A.,Field, M.J.,Adam, V.,Bourgeois, D.
The nature of transient dark States in a photoactivatable fluorescent protein.
J.Am.Chem.Soc., 133:18586-18589, 2011

PubMed Abstract: Fluorescent proteins (FPs) of the green fluorescent protein family blink and bleach like all fluorophores. However, contrary to organic dyes, the mechanisms by which transient losses of fluorescence occur in FPs have received little attention. Here, we focus on the photoactivatable IrisFP, for which a transient non-fluorescent chromophoric state with distorted geometry was recently reported (Adam, V.; et al. J. Am. Chem. Soc. 009, 131, 18063). We investigated the chemical nature of this blinked state by employing quantum chemical/molecular mechanical calculations. Our findings suggest two previously unidentified dark states that display similar distorted chromophores with a transiently ruptured π-electron system. Both are protonated at atom C(α) of the chromophore methylene bridge. Transient protonation may occur via proton transfer from the nearby Arg66 either in the triplet state T(1) after intersystem crossing or in an anionic radical (doublet) ground state. As Arg66 is conserved in green-to-red photoconvertible FPs, these dark states are predicted to be common to all these proteins. We also suggest that C(α) protonated dark states may accelerate photobleaching by favoring decarboxylation of the fully conserved Glu212.

PubMed: 22039963
DOI: 10.1021/ja2085355

実験手法

X-RAY DIFFRACTION (2 Å)