2POX

Dark state structure of the reversibly switchable fluorescent protein Dronpa

Summary for 2POX

• Entry DOI: 10.2210/pdb2pox/pdb
• Related: 2IE2 2IOV
• Descriptor: Fluorescent protein Dronpa (2 entities in total)
• Functional Keywords: luminescent protein; reversibly switchable fluorescent protein; green-fluorescent protein-like protein, fluorescent protein
• Biological source: Echinophyllia sp. SC22
• Total number of polymer chains: 4
• Total formula weight: 116987.85

Authors

Trowitzsch, S.,Weber, G.,Wahl, M.C. (deposition date: 2007-04-27, release date: 2007-07-17, Last modification date: 2024-10-30)

Primary citation

Andresen, M.,Stiel, A.C.,Trowitzsch, S.,Weber, G.,Eggeling, C.,Wahl, M.C.,Hell, S.W.,Jakobs, S.
Structural basis for reversible photoswitching in Dronpa
Proc.Natl.Acad.Sci.Usa, 104:13005-13009, 2007

PubMed Abstract: Dronpa is a novel GFP-like fluorescent protein with exceptional light-controlled switching properties. It may be reversibly switched between a fluorescent on-state and a nonfluorescent off-state by irradiation with light. To elucidate the molecular basis of the switching mechanism, we generated reversibly switchable Dronpa protein crystals. Using these crystals we determined the elusive dark-state structure of Dronpa at 1.95-A resolution. We found that the photoswitching results in a cis-trans isomerization of the chromophore accompanied by complex structural rearrangements of four nearby amino acid residues. Because of this cascade of intramolecular events, the chromophore is exposed to distinct electrostatic surface potentials, which are likely to influence the protonation equilibria at the chromophore. We suggest a comprehensive model for the light-induced switching mechanism, connecting a cascade of structural rearrangements with different protonation states of the chromophore.

PubMed: 17646653
DOI: 10.1073/pnas.0700629104

Experimental method

X-RAY DIFFRACTION (1.946 Å)