7OY8

Cryo-EM structure of the Rhodospirillum rubrum RC-LH1 complex

Summary for 7OY8

• Entry DOI: 10.2210/pdb7oy8/pdb
• Related: 7O0U 7O0V 7O0W 7O0X
• EMDB information: 13110
• Descriptor: Light-harvesting protein B-870 beta chain, (2R,5R,11R,14R)-5,8,11-trihydroxy-5,11-dioxido-17-oxo-2,14-bis(tetradecanoyloxy)-4,6,10,12,16-pentaoxa-5,11-diphosphatriacont-1-yl tetradecanoate, BACTERIOPHEOPHYTIN A, ... (18 entities in total)
• Functional Keywords: photosynthesis, light-harvesting complex, reaction centre, purple bacteria, membrane protein, structural protein
• Biological source: Rhodospirillum rubrum (strain ATCC 11170 / ATH 1.1.1 / DSM 467 / LMG 4362 / NCIMB 8255 / S1); More
• Total number of polymer chains: 35
• Total formula weight: 339533.05

Authors

Qian, P.,Croll, T.I.,Castro, H.P.,Moriarty, N.W.,sader, K.,Hunter, C.N. (deposition date: 2021-06-23, release date: 2021-09-22, Last modification date: 2024-11-13)

Primary citation

Qian, P.,Croll, T.I.,Swainsbury, D.J.K.,Castro-Hartmann, P.,Moriarty, N.W.,Sader, K.,Hunter, C.N.
Cryo-EM structure of the Rhodospirillum rubrum RC-LH1 complex at 2.5 angstrom.
Biochem.J., 478:3253-3263, 2021

PubMed Abstract: The reaction centre light-harvesting 1 (RC-LH1) complex is the core functional component of bacterial photosynthesis. We determined the cryo-electron microscopy (cryo-EM) structure of the RC-LH1 complex from Rhodospirillum rubrum at 2.5 Å resolution, which reveals a unique monomeric bacteriochlorophyll with a phospholipid ligand in the gap between the RC and LH1 complexes. The LH1 complex comprises a circular array of 16 αβ-polypeptide subunits that completely surrounds the RC, with a preferential binding site for a quinone, designated QP, on the inner face of the encircling LH1 complex. Quinols, initially generated at the RC QB site, are proposed to transiently occupy the QP site prior to traversing the LH1 barrier and diffusing to the cytochrome bc1 complex. Thus, the QP site, which is analogous to other such sites in recent cryo-EM structures of RC-LH1 complexes, likely reflects a general mechanism for exporting quinols from the RC-LH1 complex.

PubMed: 34402504
DOI: 10.1042/BCJ20210511

Experimental method

ELECTRON MICROSCOPY (2.5 Å)