Revealing the excited-state dynamics of the fluorescent protein Dendra2.
Green-to-red photoconversion is a reaction that occurs in a limited number of fluorescent proteins and that is currently mechanistically debated. In this contribution, we report on our investigation of the photoconvertible fluorescent protein Dendra2 by employing a combination of pump-probe, up-conversion and single photon timing spectroscopic techniques. Our findings indicate that upon excitation of the neutral green state an excited state proton transfer proceeds with a time constant of 3.4 ps between the neutral green and the anionic green states. In concentrated solution we detected resonance energy transfer (25 ps time constant) between green and red monomers. The time-resolved emission spectra suggest also the formation of a super-red species, first observed for DsRed (a red fluorescent protein from the corallimorph species Discosoma) and consistent with peculiar structural details present in both proteins.
Division of Molecular Imaging and Photonics, Department of Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200F, 3001 Heverlee, Belgium.
Eduard
E
Fron
Mark
M
Van der Auweraer
Benjamien
B
Moeyaert
Jan
J
Michiels
Hideaki
H
Mizuno
Johan
J
Hofkens
Virgile
V
Adam
D000818:Animals; D037421:Anthozoa / Q000378:metabolism; D019281:Dimerization; D031541:Fluorescence Resonance Energy Transfer; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008164:Luminescent Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics
C583169:Dendra2 protein, Dendronephthya; D008164:Luminescent Proteins; D011994:Recombinant Proteins; C413663:fluorescent protein 583