Photoswitching of the Fluorescent Protein asFP595: Mechanism, Proton Pathways, and Absorption Spectra

Schäfer, Lars; Groenhof, Gerrit; Klingen, Astrid R.; Ullmann, G. Matthias; Boggio‐Pasqua, Martial; Robb, Michael A.; Grubmüller, Helmut

doi:10.1002/ange.200602315

Cited by 49 publications

(93 citation statements)

References 47 publications

(49 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The QM/MM study by Nemukhin and co-workers considered the kindling fluorescent protein asFP595 [260] on the basis of the effective fragment potential method. The same protein was later studied by Schäfer et al [261] with TDDFT/OPLS (OPLS: optimized potentials for liquid simulations) calculations. It is interesting to note that the charges in the environmental system employed in the electrostatic coupling were represented by Gaussian functions instead of point charges, which in principle allows for a more accurate modeling of the Coulomb potential in the environment.…”

Section: Gfpmentioning

confidence: 99%

Subsystem‐Based Theoretical Spectroscopy of Biomolecules and Biomolecular Assemblies

Neugebauer

2009

ChemPhysChem

123

View full text Add to dashboard Cite

The absorption properties of chromophores in biomolecular systems are subject to several fine-tuning mechanisms. Specific interactions with the surrounding protein environment often lead to significant changes in the excitation energies, but bulk dielectric effects can also play an important role. Moreover, strong excitonic interactions can occur in systems with several chromophores at close distances. For interpretation purposes, it is often desirable to distinguish different types of environmental effects, such as geometrical, electrostatic, polarization, and response (or differential polarization) effects. Methods that can be applied for theoretical analyses of such effects are reviewed herein, ranging from continuum and point-charge models to explicit quantum chemical subsystem methods for environmental effects. Connections to physical model theories are also outlined. Prototypical applications to optical spectra and excited states of fluorescent proteins, biomolecular photoreceptors, and photosynthetic protein complexes are discussed.

show abstract

Section: Gfpmentioning

confidence: 99%

Subsystem‐Based Theoretical Spectroscopy of Biomolecules and Biomolecular Assemblies

Neugebauer

2009

ChemPhysChem

123

View full text Add to dashboard Cite

show abstract

“…16,19,21,33 The zwitterionic chromophore has been reported to play a crucial role in the photoswitchable fluorescent protein asFP595. 33 On the basis of simulated absorption spectra of asFP595, supported by pK a calculations, the trans wild type has a zwitterionic chromophore and the cis mutant of asFP595 has a neutral chromophore. A mechanism involving trans−cis isomerization of the chromophore, combined with several proton transfers, was proposed to underlie the photoactivation process.…”

Section: Introductionmentioning

confidence: 99%

Computational Study of Absorption Spectra of the Photoconvertible Fluorescent Protein EosFP in Different Protonation States

Imhof¹

2012

J. Chem. Theory Comput.

View full text Add to dashboard Cite

Absorption spectra of the green-to-red convertible fluorescent protein EosFP have been computed in a hybrid quantum mechanical/molecular mechanical (QM/MM) framework. The experimentally observed absorption maximum at ∼390 nm is well reproduced by the protein with a neutral chromophore, and the anionic form is computed to absorb close to the experimentally determined maximum at ∼500 nm. Absorption of a zwitterionic form is calculated to lie in the same spectral region; however, this species cannot be unambiguously assigned to the experimental spectra. Variation of the protonation states of residues surrounding the chromophore do not have significant impact on the positions of the absorption maxima. In particular, protonation of Glu212 leaves the calculated spectra largely unaffected. This is consistent with the spectra of the E212Q mutant, which differ from the wild-type spectra only in the intensities but not in the positions of the absorption bands.

show abstract

“…One of the most intriguing member from the family of the green fluorescent proteins (GFP) [1], the so-called kindling protein asFP595, which is the Ala143Gly mutant of the chromoprotein asCP [2] from the sea anemone Anemonia sulcata, attracts considerable attention in recent years [3][4][5][6][7][8][9][10][11][12]. This protein is initially non-fluorescent, but in response to intense green light irradiation at 568 nm it becomes brightly fluorescent (kindles) with emission at 595 nm.…”

Section: Introductionmentioning

confidence: 99%

Simulations on the kindling mechanism of the asFP595 fluorescent protein

Grigorenko

Nemukhin

Savitsky

2008

Small Animal Whole-Body Optical Imaging Based on Genetically Engineered Probes

View full text Add to dashboard Cite

We report the results of quantum mechanical -molecular mechanical (QM/MM) simulations aiming to elucidate the mechanism of kindling of the initially non-fluorescent protein asFP595, which is a mutated variant of the chromoprotein asCP from the sea anemone Anemonia sulcata. asFP595 becomes brightly fluorescent (kindles) with emission at 595 nm in response to intense light irradiation at 568 nm. In simulations, we use the flexible effective fragment QM/MM method with the complete active space self-consistent field (CASSCF) wavefunctions in the quantum part and the AMBER force field parameters in the molecular mechanical part. We analyze the computed scans over potential energy surfaces of the ground and excited electronic states and consider details of the working hypothesis that the trans-cis isomerization of the chromophore group inside the protein is responsible for kindling.

show abstract

Photoswitching of the Fluorescent Protein asFP595: Mechanism, Proton Pathways, and Absorption Spectra

Cited by 49 publications

References 47 publications

Subsystem‐Based Theoretical Spectroscopy of Biomolecules and Biomolecular Assemblies

Subsystem‐Based Theoretical Spectroscopy of Biomolecules and Biomolecular Assemblies

Computational Study of Absorption Spectra of the Photoconvertible Fluorescent Protein EosFP in Different Protonation States

Simulations on the kindling mechanism of the asFP595 fluorescent protein

Contact Info

Product

Resources

About