2PHY

PHOTOACTIVE YELLOW PROTEIN, DARK STATE (UNBLEACHED)

「1PHY」から置き換えられました

2PHY の概要

• エントリーDOI: 10.2210/pdb2phy/pdb
• 分子名称: PHOTOACTIVE YELLOW PROTEIN, 4'-HYDROXYCINNAMIC ACID (3 entities in total)
• 機能のキーワード: light sensor for negative phototaxis, photoreceptor
• 由来する生物種: Halorhodospira halophila
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 14052.73

構造登録者

Borgstahl, G.E.O.,Getzoff, E.D. (登録日: 1995-04-12, 公開日: 1995-10-15, 最終更新日: 2025-03-26)

主引用文献

Borgstahl, G.E.,Williams, D.R.,Getzoff, E.D.
1.4 A structure of photoactive yellow protein, a cytosolic photoreceptor: unusual fold, active site, and chromophore.
Biochemistry, 34:6278-6287, 1995

PubMed Abstract: A photosensing protein directs light energy captured by its chromophore into a photocycle. The protein's structure must accommodate the photocycle and promote the resulting chemical or conformational changes that lead to signal transduction. The 1.4 A crystallographic structure of photoactive yellow protein, determined by multiple isomorphous replacement methods, provides the first view at atomic resolution of a protein with a photocycle. The alpha/beta fold, which differs from the original chain tracing, shows striking similarity to distinct parts of the signal transduction proteins profilin and the SH2 domain. In the dark state structure of photoactive yellow protein, the novel 4-hydroxycinnamyl chromophore, covalently attached to Cys69, is buried within the major hydrophobic core of the protein and is tethered at both ends by hydrogen bonds. In the active site, the yellow anionic form of the chromophore is stabilized by hydrogen bonds from the side chains of Tyr42 and buried Glu46 to the phenolic oxygen atom and by electrostatic complementarity with the positively charged guanidinium group of Arg52. Thr50 further interlocks Tyr42, Glu46, and Arg52 through a network of active site hydrogen bonds. Arg52, located in a concavity of the protein surface adjacent to the dominant patch of negative electrostatic potential, shields the chromophore from solvent and is positioned to form a gateway for the phototactic signal. Overall, the high-resolution structure of photoactive yellow protein supports a mechanism whereby electrostatic interactions create an active site poised for photon-induced rearrangements and efficient protein-mediated signal transduction.

PubMed: 7756254
DOI: 10.1021/bi00019a004

実験手法

X-RAY DIFFRACTION (1.4 Å)