Ultrafast Photoconversion Dynamics of the Knotless Phytochrome SynCph2

Fischer, Tobias; van Wilderen, Luuk J. G. W.; Gnau, Petra; Bredenbeck, Jens; Essen, Lars-Oliver; Wachtveitl, Josef; Slavov, Chavdar

doi:10.3390/ijms221910690

Open AccessArticle

Ultrafast Photoconversion Dynamics of the Knotless Phytochrome SynCph2

by

Tobias Fischer

¹

,

Luuk J. G. W. van Wilderen

²

,

Petra Gnau

³,

Jens Bredenbeck

²,

Lars-Oliver Essen

^3,4

,

Josef Wachtveitl

^1,*

and

Chavdar Slavov

^1,*

¹

Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt am Main, Max-von-Laue Straße 7, 60438 Frankfurt, Germany

²

Institute of Biophysics, Goethe University Frankfurt am Main, Max-von-Laue Straße 1, 60438 Frankfurt, Germany

³

Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany

⁴

Center for Synthetic Microbiology, Philipps-Universität Marburg, Hans-Meerwein-Straße 6, 35032 Marburg, Germany

^*

Authors to whom correspondence should be addressed.

Int. J. Mol. Sci. 2021, 22(19), 10690; https://doi.org/10.3390/ijms221910690

Submission received: 24 August 2021 / Revised: 24 September 2021 / Accepted: 28 September 2021 / Published: 2 October 2021

(This article belongs to the Special Issue Excited Electronic States of Organic Molecules–50 Years of an Interdisciplinary Research —A Tribute to Sir George Porter on the Occasion of His 100th Birthday)

Download

Browse Figures

Versions Notes

Abstract

The family of phytochrome photoreceptors contains proteins with different domain architectures and spectral properties. Knotless phytochromes are one of the three main subgroups classified by their distinct lack of the PAS domain in their photosensory core module, which is in contrast to the canonical PAS-GAF-PHY array. Despite intensive research on the ultrafast photodynamics of phytochromes, little is known about the primary kinetics in knotless phytochromes. Here, we present the ultrafast P_r ⇆ P_fr photodynamics of SynCph2, the best-known knotless phytochrome. Our results show that the excited state lifetime of P_r* (~200 ps) is similar to bacteriophytochromes, but much longer than in most canonical phytochromes. We assign the slow P_r* kinetics to relaxation processes of the chromophore-binding pocket that controls the bilin chromophore’s isomerization step. The P_fr photoconversion dynamics starts with a faster excited state relaxation than in canonical phytochromes, but, despite the differences in the respective domain architectures, proceeds via similar ground state intermediate steps up to Meta-F. Based on our observations, we propose that the kinetic features and overall dynamics of the ultrafast photoreaction are determined to a great extent by the geometrical context (i.e., available space and flexibility) within the binding pocket, while the general reaction steps following the photoexcitation are most likely conserved among the red/far-red phytochromes.

Keywords: tetrapyrrole-binding photoreceptors; phytochromes; photochemistry; photoisomerization; time-resolved spectroscopy

Share and Cite

MDPI and ACS Style

Fischer, T.; van Wilderen, L.J.G.W.; Gnau, P.; Bredenbeck, J.; Essen, L.-O.; Wachtveitl, J.; Slavov, C. Ultrafast Photoconversion Dynamics of the Knotless Phytochrome SynCph2. Int. J. Mol. Sci. 2021, 22, 10690. https://doi.org/10.3390/ijms221910690

AMA Style

Fischer T, van Wilderen LJGW, Gnau P, Bredenbeck J, Essen L-O, Wachtveitl J, Slavov C. Ultrafast Photoconversion Dynamics of the Knotless Phytochrome SynCph2. International Journal of Molecular Sciences. 2021; 22(19):10690. https://doi.org/10.3390/ijms221910690

Chicago/Turabian Style

Fischer, Tobias, Luuk J. G. W. van Wilderen, Petra Gnau, Jens Bredenbeck, Lars-Oliver Essen, Josef Wachtveitl, and Chavdar Slavov. 2021. "Ultrafast Photoconversion Dynamics of the Knotless Phytochrome SynCph2" International Journal of Molecular Sciences 22, no. 19: 10690. https://doi.org/10.3390/ijms221910690

APA Style

Fischer, T., van Wilderen, L. J. G. W., Gnau, P., Bredenbeck, J., Essen, L.-O., Wachtveitl, J., & Slavov, C. (2021). Ultrafast Photoconversion Dynamics of the Knotless Phytochrome SynCph2. International Journal of Molecular Sciences, 22(19), 10690. https://doi.org/10.3390/ijms221910690

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Menu

Ultrafast Photoconversion Dynamics of the Knotless Phytochrome SynCph2

Abstract

Share and Cite

Article Metrics

Article Access Statistics

Further Information

Guidelines

MDPI Initiatives

Follow MDPI