Molecular mechanism of photoactivation and structural location of the cyanobacterial orange carotenoid protein.

ABSTRACT: The orange carotenoid protein (OCP) plays a photoprotective role in cyanobacterial photosynthesis similar to that of nonphotochemical quenching in higher plants. Under high-light conditions, the OCP binds to the phycobilisome (PBS) and reduces the extent of transfer of energy to the photosystems. The protective cycle starts from a light-induced activation of the OCP. Detailed information about the molecular mechanism of this process as well as the subsequent recruitment of the active OCP to the phycobilisome are not known. We report here our investigation on the OCP photoactivation from the cyanobacterium Synechocystis sp. PCC 6803 by using a combination of native electrospray mass spectrometry (MS) and protein cross-linking. We demonstrate that native MS can capture the OCP with its intac

SUBMITTER: Zhang H 

PROVIDER: S-EPMC3963514 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature