Dataset Information

Structural characterization of the reaction center-light harvesting 1-PufXY complex from Rhodobacter sphaeroides

ABSTRACT: Photosynthesis in purple bacteria, represented by Rhodobacter sphaeroides as a long-established model organism, utilizes a protein-cofactor complex to capture solar energy. This complex is embedded in specialized spherical membrane structures and comprises a central reaction center (RC) encircled by a ring of light harvesting 1 (LH1) polypeptides. The energy derived from light absorption drives the reduction of ubiquinone, entering from the membrane, to generate ubiquinol. The photosynthetic cycle is therefore dependent on the exchange of ubiquinone and ubiquinol to and from the RC. This exchange requires an additional protein (PufX) which prevents complete closure of the LH1 ring, leaving a channel which connects the RC with the membrane. The structure of the RC-LH1-PufX complex is under investigation by cryo-EM, revealing the presence of a previously undiscovered protein (PufY) that is also involved in channel formation. Proteomic analysis has verified the identities of the expected protein components of this complex, additionally confirming the presence of the newly-discovered PufY polypeptide mapped into the cryo-EM structure.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Rhodobacter Sphaeroides 2.4.1

SUBMITTER: Philip Jackson

LAB HEAD: Christopher Neil Hunter

PROVIDER: PXD028048 | Pride | 2022-02-15

REPOSITORIES: Pride

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Dataset's files

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			Action	DRS
	20210716_PJ_ProteinU_wt-1_20210716154626.raw	Raw
	20210716_PJ_ProteinU_wt-1_20210716154626.raw_20210718_Byonic.xlsx	Xlsx
	20210716_PJ_ProteinU_wt-2.raw	Raw
	20210716_PJ_ProteinU_wt-2.raw_20210718_Byonic.xlsx	Xlsx
	20210716_PJ_ProteinU_wt-3.raw	Raw

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Publications

Cryo-EM structure of the monomeric Rhodobacter sphaeroides RC-LH1 core complex at 2.5 Å.

Qian Pu P Swainsbury David J K DJK Croll Tristan I TI Salisbury Jack H JH Martin Elizabeth C EC Jackson Philip J PJ Hitchcock Andrew A Castro-Hartmann Pablo P Sader Kasim K Hunter C Neil CN

The Biochemical journal 20211001 20

Reaction centre light-harvesting 1 (RC-LH1) complexes are the essential components of bacterial photosynthesis. The membrane-intrinsic LH1 complex absorbs light and the energy migrates to an enclosed RC where a succession of electron and proton transfers conserves the energy as a quinol, which is exported to the cytochrome bc1 complex. In some RC-LH1 variants quinols can diffuse through small pores in a fully circular, 16-subunit LH1 ring, while in others missing LH1 subunits create a gap for qu ...[more]

PMID: 34590677

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