Molecular Origin of Photoprotection in Cyanobacteria Probed by Watermarked Femtosecond Stimulated Raman Spectroscopy

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60076658%3A12310%2F18%3A43897247" target="_blank" >RIV/60076658:12310/18:43897247 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68378271:_____/18:00501677 RIV/61388971:_____/18:00501677

Výsledek na webu

<a href="http://europepmc.org/backend/ptpmcrender.fcgi?accid=PMC5942868&blobtype=pdf" target="_blank" >http://europepmc.org/backend/ptpmcrender.fcgi?accid=PMC5942868&blobtype=pdf</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.jpclett.8b00663" target="_blank" >10.1021/acs.jpclett.8b00663</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Molecular Origin of Photoprotection in Cyanobacteria Probed by Watermarked Femtosecond Stimulated Raman Spectroscopy

Popis výsledku v původním jazyce

Photoprotection is fundamental in photosynthesis to avoid oxidative photodamage upon excess light exposure. Excited chlorophylls (Chl) are quenched by carotenoids, but the precise molecular origin remains controversial. The cyanobacterial HliC protein belongs to the Hlip family ancestral to plant light-harvesting complexes, and binds Chl a and beta-carotene in 2:1 ratio. We analyzed HliC by watermarked femtosecond stimulated Raman spectroscopy to follow the time evolution of its vibrational modes. We observed a 2 ps rise of the C=C stretch band of the 2A(g)(-) (S-1) state of beta- carotene upon CM a excitation, demonstrating energy transfer quenching and fast excess-energy dissipation. We detected two distinct beta-carotene conformers by the C=C stretch frequency of the 2A(g)(-) (S-1) state, but only the beta-carotene whose 2A(g)(-) energy level is significantly lowered and has a lower C=C stretch frequency is involved in quenching. It implies that the low carotenoid S-1 energy that results from specific pigment-protein or pigment-pigment interactions is the key property for creating a dissipative energy channel. We conclude that watermarked femtosecond stimulated Raman spectroscopy constitutes a promising experimental method to assess energy transfer and quenching mechanisms in oxygenic photosynthesis.

Název v anglickém jazyce

Molecular Origin of Photoprotection in Cyanobacteria Probed by Watermarked Femtosecond Stimulated Raman Spectroscopy

Popis výsledku anglicky

Photoprotection is fundamental in photosynthesis to avoid oxidative photodamage upon excess light exposure. Excited chlorophylls (Chl) are quenched by carotenoids, but the precise molecular origin remains controversial. The cyanobacterial HliC protein belongs to the Hlip family ancestral to plant light-harvesting complexes, and binds Chl a and beta-carotene in 2:1 ratio. We analyzed HliC by watermarked femtosecond stimulated Raman spectroscopy to follow the time evolution of its vibrational modes. We observed a 2 ps rise of the C=C stretch band of the 2A(g)(-) (S-1) state of beta- carotene upon CM a excitation, demonstrating energy transfer quenching and fast excess-energy dissipation. We detected two distinct beta-carotene conformers by the C=C stretch frequency of the 2A(g)(-) (S-1) state, but only the beta-carotene whose 2A(g)(-) energy level is significantly lowered and has a lower C=C stretch frequency is involved in quenching. It implies that the low carotenoid S-1 energy that results from specific pigment-protein or pigment-pigment interactions is the key property for creating a dissipative energy channel. We conclude that watermarked femtosecond stimulated Raman spectroscopy constitutes a promising experimental method to assess energy transfer and quenching mechanisms in oxygenic photosynthesis.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10608 - Biochemistry and molecular biology

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2018

Kód důvěrnosti údajů

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

Název periodika

JOURNAL OF PHYSICAL CHEMISTRY LETTERS

ISSN

1948-7185

e-ISSN

—

Svazek periodika

9

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

5

Strana od-do

1788-1792

Kód UT WoS článku

000429626900050

EID výsledku v databázi Scopus

2-s2.0-85045009663