How reduced excitonic coupling enhances light harvesting in the main photosynthetic antennae of diatoms
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F17%3A10370629" target="_blank" >RIV/00216208:11320/17:10370629 - isvavai.cz</a>
Result on the web
<a href="http://dx.doi.org/10.1073/pnas.1714656115" target="_blank" >http://dx.doi.org/10.1073/pnas.1714656115</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1073/pnas.1714656115" target="_blank" >10.1073/pnas.1714656115</a>
Alternative languages
Result language
angličtina
Original language name
How reduced excitonic coupling enhances light harvesting in the main photosynthetic antennae of diatoms
Original language description
Strong excitonic interactions are a key design strategy in photosynthetic light harvesting, expanding the spectral cross-section for light absorption and creating considerably faster and more robust excitation energy transfer. These molecular excitons are a direct result of exceptionally densely packed pigments in photosynthetic proteins. The main light-harvesting complexes of diatoms, known as fucoxan-thin-chlorophyll proteins (FCPs), are an exception, displaying surprisingly weak excitonic coupling between their chlorophyll (Chl) a's, despite a high pigment density. Here, we show, using single-molecule spectroscopy, that the FCP complexes of Cyclotella meneghiniana switch frequently into stable, strongly emissive states shifted 4-10 nm toward the red. A few percent of isolated FCPa complexes and similar to 20% of isolated FCPb complexes, on average, were observed to populate these previously unobserved states, percentages that agree with the steady-state fluorescence spectra of FCP ensembles. Thus, the complexes use their enhanced sensitivity to static disorder to increase their light-harvesting capability in a number of ways. A disordered exciton model based on the structure of the main plant light-harvesting complex explains the red-shifted emission by strong localization of the excitation energy on a single Chl a pigment in the terminal emitter domain due to very specific pigment orientations. We suggest that the specific construction of FCP gives the complex a unique strategy to ensure that its light-harvesting function remains robust in the fluctuating protein environment despite limited excitonic interactions.
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
10610 - Biophysics
Result continuities
Project
<a href="/en/project/GA17-22160S" target="_blank" >GA17-22160S: Quantum theory of excitation energy transfer and advanced optical spectroscopy: from small dye molecules to light-harvesting complexes</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2017
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Proceedings of the National Academy of Sciences of the United States of America
ISSN
0027-8424
e-ISSN
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Volume of the periodical
114
Issue of the periodical within the volume
52
Country of publishing house
US - UNITED STATES
Number of pages
9
Pages from-to
"E11063"-"E11071"
UT code for WoS article
000418722400002
EID of the result in the Scopus database
2-s2.0-85039709582