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-Structure paper
Title | Asymmetric structure of the native Rhodobacter sphaeroides dimeric LH1-RC complex. |
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Journal, issue, pages | Nat Commun, Vol. 13, Issue 1, Page 1904, Year 2022 |
Publish date | Apr 7, 2022 |
Authors | Kazutoshi Tani / Ryo Kanno / Riku Kikuchi / Saki Kawamura / Kenji V P Nagashima / Malgorzata Hall / Ai Takahashi / Long-Jiang Yu / Yukihiro Kimura / Michael T Madigan / Akira Mizoguchi / Bruno M Humbel / Zheng-Yu Wang-Otomo / |
PubMed Abstract | Rhodobacter sphaeroides is a model organism in bacterial photosynthesis, and its light-harvesting-reaction center (LH1-RC) complex contains both dimeric and monomeric forms. Here we present cryo-EM ...Rhodobacter sphaeroides is a model organism in bacterial photosynthesis, and its light-harvesting-reaction center (LH1-RC) complex contains both dimeric and monomeric forms. Here we present cryo-EM structures of the native LH1-RC dimer and an LH1-RC monomer lacking protein-U (ΔU). The native dimer reveals several asymmetric features including the arrangement of its two monomeric components, the structural integrity of protein-U, the overall organization of LH1, and rigidities of the proteins and pigments. PufX plays a critical role in connecting the two monomers in a dimer, with one PufX interacting at its N-terminus with another PufX and an LH1 β-polypeptide in the other monomer. One protein-U was only partially resolved in the dimeric structure, signaling different degrees of disorder in the two monomers. The ΔU LH1-RC monomer was half-moon-shaped and contained 11 α- and 10 β-polypeptides, indicating a critical role for protein-U in controlling the number of αβ-subunits required for dimer assembly and stabilization. These features are discussed in relation to membrane topology and an assembly model proposed for the native dimeric complex. |
External links | Nat Commun / PubMed:35393413 / PubMed Central |
Methods | EM (single particle) |
Resolution | 2.63 - 2.75 Å |
Structure data | EMDB-32192, PDB-7vy2: EMDB-32193, PDB-7vy3: |
Chemicals | ChemComp-BCL: ChemComp-BPH: ChemComp-U10: ChemComp-LMT: ChemComp-PGV: ChemComp-FE: ChemComp-SPO: ChemComp-CDL: ChemComp-PTY: ChemComp-LDA: |
Source |
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Keywords | PHOTOSYNTHESIS / LH1-RC COMPLEX / PURPLE BACTERIA |