Oligomerization processes limit photoactivation and recovery of the orange carotenoid protein

• DOI: 10.1016/j.bpj.2022.07.004
• Publication Date: 2022-07-06T16:47:06Z
• Authors: Elena A. Andreeva; Stanisław Niziński; Adjélé Wilson; Matteo Levantino; Elke De Zitter; Rory Munro; Fernando Muzzopappa; Aurélien Thureau; Ninon Zala; Gotard Burdzinski; Michel Sliwa; Diana Kirilovsky; Giorgio Schirò; Jacques-Philippe ...
• Keywords: Photoprotection; Dark state

The orange carotenoid protein (OCP) is a photoactive involved in cyanobacterial photoprotection by quenching of the excess light-harvested energy. photoactivation mechanism remains elusive, part due to absence data pertaining timescales over which structural changes take place. It also unclear whether or not oligomerization dark-adapted and light-adapted OCP could play role regulation its energy-quenching activity. Here, we probed photoinduced combination static time-resolved X-ray scattering steady-state transient optical spectroscopy visible range. Our results suggest that partakes photocycle, with different oligomers slowing down overall thermal recovery state OCP. They furthermore reveal upon non-photoproductive excitation numbed forms, non-photoexcitable for at least ≈0.5 μs after absorption first photon.