4OGQ

Internal Lipid Architecture of the Hetero-Oligomeric Cytochrome b6f Complex

Summary for 4OGQ

• Entry DOI: 10.2210/pdb4ogq/pdb
• Related: 1Q90 1VF5 2E74 2E75 2E76 2ZT9 3CX5 4H0L 4H13 4H44
• Descriptor: Cytochrome b6, UNDECYL-MALTOSIDE, (1R)-2-(dodecanoyloxy)-1-[(phosphonooxy)methyl]ethyl tetradecanoate, ... (26 entities in total)
• Functional Keywords: electron transfer, plastocyanin, cytochrome c6, thylakoid membrane, electron transport
• Biological source: Nostoc sp.; More
• Cellular location: Cellular thylakoid membrane; Multi-pass membrane protein (By similarity): P0A384 Q93SX1; Cellular thylakoid membrane; Single-pass membrane protein (By similarity): Q93SW9 Q93SX0 Q8YVQ2 P0A3Y1 P58246 P61048
• Total number of polymer chains: 8
• Total formula weight: 126320.19

Authors

Hasan, S.S.,Cramer, W.A. (deposition date: 2014-01-16, release date: 2014-05-14, Last modification date: 2024-12-25)

Primary citation

Hasan, S.S.,Cramer, W.A.
Internal Lipid Architecture of the Hetero-Oligomeric Cytochrome b6f Complex.
Structure, 22:1008-1015, 2014

PubMed Abstract: The role of lipids in the assembly, structure, and function of hetero-oligomeric membrane protein complexes is poorly understood. The dimeric photosynthetic cytochrome b6f complex, a 16-mer of eight distinct subunits and 26 transmembrane helices, catalyzes transmembrane proton-coupled electron transfer for energy storage. Using a 2.5 Å crystal structure of the dimeric complex, we identified 23 distinct lipid-binding sites per monomer. Annular lipids are proposed to provide a connection for super-complex formation with the photosystem-I reaction center and the LHCII kinase enzyme for transmembrane signaling. Internal lipids mediate crosslinking to stabilize the domain-swapped iron-sulfur protein subunit, dielectric heterogeneity within intermonomer and intramonomer electron transfer pathways, and dimer stabilization through lipid-mediated intermonomer interactions. This study provides a complete structure analysis of lipid-mediated functions in a multi-subunit membrane protein complex and reveals lipid sites at positions essential for assembly and function.

PubMed: 24931468
DOI: 10.1016/j.str.2014.05.004

Experimental method

X-RAY DIFFRACTION (2.501 Å)