Excitation Energy Transfer between Higher Excited States of Photosynthetic Pigments: 2. Chlorophyll b is a B Band Excitation Trap
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F23%3A10476899" target="_blank" >RIV/00216208:11320/23:10476899 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=XP-UNBz42m" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=XP-UNBz42m</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1021/acsomega.3c05896" target="_blank" >10.1021/acsomega.3c05896</a>
Alternative languages
Result language
angličtina
Original language name
Excitation Energy Transfer between Higher Excited States of Photosynthetic Pigments: 2. Chlorophyll b is a B Band Excitation Trap
Original language description
Chlorophylls (Chls) are known for fast, subpicosecond internal conversion (IC) from ultraviolet/blue absorbing ("B" or "Soret" states) to the energetically lower, red light-absorbing Q states. Consequently, excitation energy transfer (EET) in photosynthetic pigment-protein complexes involving the B states has so far not been considered. We present, for the first time, a theoretical framework for the existence of B-B EET in tightly coupled Chl aggregates such as photosynthetic pigment-protein complexes. We show that according to a Fo''rster resonance energy transport (FRET) scheme, unmodulated B-B EET has an unexpectedly high range. Unsuppressed, it could pose an existential threat-the damage potential of blue light for photochemical reaction centers (RCs) is well-known. This insight reveals so-far undescribed roles for carotenoids (Crts, cf. previous article in this series) and Chl b (this article) of possibly vital importance. Our model system is the photosynthetic antenna pigment-protein complex (CP29). The focus of the study is on the role of Chl b for EET in the Q and B bands. Further, the initial excited pigment distribution in the B band is computed for relevant solar irradiation and wavelength-centered laser pulses. It is found that both accessory pigment classes compete efficiently with Chl a absorption in the B band, leaving only 40% of B band excitations for Chl a. B state population is preferentially relocated to Chl b after excitation of any Chls, due to a near-perfect match of Chl b B band absorption with Chl a B state emission spectra. This results in an efficient depletion of the Chl a population (0.66 per IC/EET step, as compared to 0.21 in a Chl a-only system). Since Chl b only occurs in the peripheral antenna complexes of plants and algae, and RCs contain only Chl a, this would automatically trap potentially dangerous B state population in the antennae, preventing forwarding to the RCs.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10301 - Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)
Result continuities
Project
<a href="/en/project/GA22-17333S" target="_blank" >GA22-17333S: Light-driven energy conversion with biohybrid assemblies in nanocontainers</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2023
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
ACS Omega
ISSN
2470-1343
e-ISSN
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Volume of the periodical
8
Issue of the periodical within the volume
43
Country of publishing house
US - UNITED STATES
Number of pages
9
Pages from-to
40015-40023
UT code for WoS article
001122382500001
EID of the result in the Scopus database
2-s2.0-85176755401