Cryo-EM Structure of the <i>Rhodobacter sphaeroides</i> Light-Harvesting 2 Complex at 2.1 A.

ABSTRACT: Light-harvesting 2 (LH2) antenna complexes augment the collection of solar energy in many phototrophic bacteria. Despite its frequent role as a model for such complexes, there has been no three-dimensional (3D) structure available for the LH2 from the purple phototroph Rhodobacter sphaeroides. We used cryo-electron microscopy (cryo-EM) to determine the 2.1 Å resolution structure of this LH2 antenna, which is a cylindrical assembly of nine αβ heterodimer subunits, each of which binds three bacteriochlorophyll a (BChl) molecules and one carotenoid. The high resolution of this structure reveals all of the interpigment and pigment-protein interactions that promote the assembly and energy-transfer properties of this complex. Near the cytoplasmic face of the complex there is a ring

SUBMITTER: Qian P 

PROVIDER: S-EPMC8775250 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature