Altering the exciton landscape by removal of specific chlorophylls in monomeric LHCII provides information on the sites of triplet formation and quenching by means of ODMR and EPR spectroscopies
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60077344%3A_____%2F21%3A00603876" target="_blank" >RIV/60077344:_____/21:00603876 - isvavai.cz</a>
Result on the web
<a href="https://www.sciencedirect.com/science/article/pii/S0005272821001146?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0005272821001146?via%3Dihub</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1016/j.bbabio.2021.148481" target="_blank" >10.1016/j.bbabio.2021.148481</a>
Alternative languages
Result language
angličtina
Original language name
Altering the exciton landscape by removal of specific chlorophylls in monomeric LHCII provides information on the sites of triplet formation and quenching by means of ODMR and EPR spectroscopies
Original language description
The triplet states populated under illumination in the monomeric light-harvesting complex II (LHCII) were analyzed by EPR and Optically Detected Magnetic Resonance (ODMR) in order to fully characterize the perturbations introduced by site-directed mutations leading to the removal of key chlorophylls. We considered the A2 and A5 mutants, lacking Chls a612(a611) and Chl a603 respectively, since these Chls have been proposed as the sites of formation of triplet states which are subsequently quenched by the luteins. Chls a612 and Chl a603 belong to the two clusters determining the low energy exciton states in the complex. Their removal is expected to significantly alter the excitation energy transfer pathways. On the basis of the TR- and pulse EPR triplet spectra, the two symmetrically related pairs constituted by Chl a612/Lut620 and Chl a603/Lut621 were both possible candidate for triplet-triplet energy transfer (TTET). However, the ODMR results clearly show that only Lut620 is involved in triplet quenching. In the A5 mutant, the Chl a612/Lut620 pair retains this pivotal photoprotective role, while the A2 mutant was found to activate an alternative pathway involving the Chl a603/Lut621pair. These results shows that LHCII is characterized by a robust photoprotective mechanism, able to adapt to the removal of individual chromophores while maintaining a remarkable degree of Chl triplet quenching. Small amounts of unquenched Chl triplet states were also detected. The analysis of the results allowed us to assign the sites of unquenched chlorophyll triplets to Chl a610 and Chl a602.
Czech name
—
Czech description
—
Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10608 - Biochemistry and molecular biology
Result continuities
Project
—
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2021
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Biochimica Et Biophysica Acta-Bioenergetics
ISSN
0005-2728
e-ISSN
1879-2650
Volume of the periodical
1862
Issue of the periodical within the volume
11
Country of publishing house
NL - THE KINGDOM OF THE NETHERLANDS
Number of pages
8
Pages from-to
148481
UT code for WoS article
000687486200003
EID of the result in the Scopus database
2-s2.0-85112313285