Paul V Sauer, Lorenzo Cupellini, Markus Sutter, Mattia Bondanza, María Agustina Domínguez Martin, Henning Kirst, David Bína, Adrian Fujiet Koh, Abhay Kotecha, Basil J Greber, Eva Nogales, Tomáš Polívka, Benedetta Mennucci, Cheryl A Kerfeld
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, showcasing its inherent flexibility...
April 5, 2024: Science Advances