Cryo-EM structure of the dimeric Rhodobacter sphaeroides RC-LH1 core complex at 2.9 A: the structural basis for dimerisation.

ABSTRACT: The dimeric reaction centre light-harvesting 1 (RC-LH1) core complex of Rhodobacter sphaeroides converts absorbed light energy to a charge separation, and then it reduces a quinone electron and proton acceptor to a quinol. The angle between the two monomers imposes a bent configuration on the dimer complex, which exerts a major influence on the curvature of the membrane vesicles, known as chromatophores, where the light-driven photosynthetic reactions take place. To investigate the dimerisation interface between two RC-LH1 monomers, we determined the cryogenic electron microscopy structure of the dimeric complex at 2.9 Å resolution. The structure shows that each monomer consists of a central RC partly enclosed by a 14-subunit LH1 ring held in an open state by PufX and protein-Y polypeptide

SUBMITTER: Qian P 

PROVIDER: S-EPMC8652583 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature