Structural and quantum chemical basis for OCP-mediated quenching of phycobilisomes
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ABSTRACT:
SUBMITTER: Paul Victor Sauer
PROVIDER: EMPIAR-11644 | biostudies-other |
REPOSITORIES: biostudies-other
Publications
Structural and quantum chemical basis for OCP-mediated quenching of phycobilisomes.
Sauer Paul V PV Cupellini Lorenzo L Sutter Markus M Bondanza Mattia M Domínguez Martin María Agustina MA Kirst Henning H Bína David D Koh Adrian Fujiet AF Kotecha Abhay A Greber Basil J BJ Nogales Eva E Polívka Tomáš T Mennucci Benedetta B Kerfeld Cheryl A CA
Science advances 20240405 14
Cyanobacteria use large antenna complexes called phycobilisomes (PBSs) for light harvesting. However, intense light triggers non-photochemical quenching, where the orange carotenoid protein (OCP) binds to PBS, dissipating excess energy as heat. The mechanism of efficiently transferring energy from phycocyanobilins in PBS to canthaxanthin in OCP remains insufficiently understood. Using cryo-electron microscopy, we unveiled the OCP-PBS complex structure at 1.6- to 2.1-angstrom resolution, showcasi ...[more]
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