Volltext-Downloads (blau) und Frontdoor-Views (grau)

Role of missing carotenoid in reducing the fluorescence of single monomeric photosystem II core complexes

  • The fluorescence of monomeric photosystem II core complexes (mPSIIcc) of the cyanobacterium Thermosynechococcus elongatus, originating from redissolved crystals, is investigated by using single-molecule spectroscopy (SMS) at 1.6 K. The emission spectra of individual mPSIIcc are dominated by sharp zero-phonon lines, showing the existence of different emitters compatible with the F685, F689, and F695 bands reported formerly. The intensity of F695 is reduced in single mPSIIcc as compared to single PSIIcc-dimers (dPSIIcc). Crystal structures show that one of the β-carotene (β-Car) cofactors located at the monomer–monomer interface in dPSIIcc is missing in mPSIIcc. This β-Car in dPSIIcc is in van der Waals distance to chlorophyll (Chl) 17 in the CP47 subunit. We suggest that this Chl contributes to the F695 emitter. A loss of β-Car cofactors in mPSIIcc preparations will lead to an increased lifetime of the triplet state of Chl 17, which can explain the reduced singlet emission of F695 as observed in SMS.

Export metadata

Additional Services

Search Google Scholar

Statistics

frontdoor_oas
Metadaten
Author of HS ReutlingenBrecht, Marc
DOI:https://doi.org/10.1039/C6CP07748J
ISSN:1463-9076
Erschienen in:Physical chemistry, chemical physics : PCCP ; a journal of European Chemical Societies
Publisher:The Royal Society of Chemistry
Place of publication:Cambridge
Document Type:Journal article
Language:English
Publication year:2017
Volume:19
Issue:20
Page Number:6
First Page:13189
Last Page:13194
DDC classes:541 Physikalische Chemie
Open access?:Nein