Dual photoisomerization on distinct potential energy surfaces in a UV-absorbing rhodopsin

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F20%3A00536453" target="_blank" >RIV/68378271:_____/20:00536453 - isvavai.cz</a>

Výsledek na webu

<a href="http://hdl.handle.net/11104/0314228" target="_blank" >http://hdl.handle.net/11104/0314228</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/jacs.0c03229" target="_blank" >10.1021/jacs.0c03229</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Dual photoisomerization on distinct potential energy surfaces in a UV-absorbing rhodopsin

Popis výsledku v původním jazyce

UV-absorbing rhodopsins are essential for UV vision and sensing in all kingdoms of life. Unlike the well-known visible-absorbing rhodopsins, which bind a protonated retinal Schiff base for light absorption, UV-absorbing rhodopsins bind an unprotonated retinal Schiff base. Thus far, the photoreaction dynamics and mechanisms of UV-absorbing rhodopsins have remained essentially unknown. Here, we report the complete excited- and ground-state dynamics of the UV form of histidine kinase rhodopsin 1 (HKR1) from eukaryotic algae, using femtosecond stimulated Raman spectroscopy (FSRS) and transient absorption spectroscopy, covering time scales from femtoseconds to milliseconds. We found that energy-level ordering is inverted with respect to visible-absorbing rhodopsins, with an optically forbidden low-lying S-1 excited state that has Ag- symmetry and a higher-lying UV-absorbing S-2 state of Bu+ symmetry. UV-photoexcitation to the S-2 state elicits a unique dual-isomerization reaction: first, C13=C14 cis-trans isomerization occurs during S-2-S-1 evolution in <100 fs. This very fast reaction features the remarkable property that the newly formed isomer appears in the excited state rather than in the ground state. Second, C15=N16 anti-syn isomerization occurs on the S-1-S-0 evolution to the ground state in 4.8 ps. We detected two ground-state unprotonated retinal photoproducts, 13-trans/15-anti (all-trans) and 13-cis/15-syn, after relaxation to the ground state. These isomers become protonated in 58 mu s and 3.2 ms, respectively, resulting in formation of the blue-absorbing form of HKR1. Our results constitute a benchmark of UV-induced photochemistry of animal and microbial rhodopsins.

Název v anglickém jazyce

Dual photoisomerization on distinct potential energy surfaces in a UV-absorbing rhodopsin

Popis výsledku anglicky

UV-absorbing rhodopsins are essential for UV vision and sensing in all kingdoms of life. Unlike the well-known visible-absorbing rhodopsins, which bind a protonated retinal Schiff base for light absorption, UV-absorbing rhodopsins bind an unprotonated retinal Schiff base. Thus far, the photoreaction dynamics and mechanisms of UV-absorbing rhodopsins have remained essentially unknown. Here, we report the complete excited- and ground-state dynamics of the UV form of histidine kinase rhodopsin 1 (HKR1) from eukaryotic algae, using femtosecond stimulated Raman spectroscopy (FSRS) and transient absorption spectroscopy, covering time scales from femtoseconds to milliseconds. We found that energy-level ordering is inverted with respect to visible-absorbing rhodopsins, with an optically forbidden low-lying S-1 excited state that has Ag- symmetry and a higher-lying UV-absorbing S-2 state of Bu+ symmetry. UV-photoexcitation to the S-2 state elicits a unique dual-isomerization reaction: first, C13=C14 cis-trans isomerization occurs during S-2-S-1 evolution in <100 fs. This very fast reaction features the remarkable property that the newly formed isomer appears in the excited state rather than in the ground state. Second, C15=N16 anti-syn isomerization occurs on the S-1-S-0 evolution to the ground state in 4.8 ps. We detected two ground-state unprotonated retinal photoproducts, 13-trans/15-anti (all-trans) and 13-cis/15-syn, after relaxation to the ground state. These isomers become protonated in 58 mu s and 3.2 ms, respectively, resulting in formation of the blue-absorbing form of HKR1. Our results constitute a benchmark of UV-induced photochemistry of animal and microbial rhodopsins.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10610 - Biophysics

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of the American Chemical Society

ISSN

0002-7863

e-ISSN

—

Svazek periodika

142

Číslo periodika v rámci svazku

26

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

10

Strana od-do

11464-11473

Kód UT WoS článku

000547329800018

EID výsledku v databázi Scopus

2-s2.0-85087468750