How orange carotenoid protein controls the excited state dynamics of canthaxanthin.

ABSTRACT: Orange Carotenoid Protein (OCP) is a ketocarotenoid-binding protein essential for photoprotection in cyanobacteria. The main steps of the photoactivated conversion which converts OCP from its resting state to the active one have been extensively investigated. However, the initial photochemical event in the ketocarotenoid which triggers the large structural changes finally leading to the active state is still not understood. Here we employ QM/MM surface hopping nonadiabatic dynamics to investigate the excited-state decay of canthaxanthin in OCP, both in the ultrafast S₂ to S₁ internal conversion and the slower decay leading back to the ground state. For the former step we show the involvement of an additional excited state, which in the literature has been often named

SUBMITTER: Arcidiacono A 

PROVIDER: S-EPMC10583711 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature