Database of articles cited by EMDB/PDB/SASBDB data

Keywords
Structure methods	All X-ray diffraction NMR electron microscopy small angle scattering neutron diffraction fiber diffraction powder diffraction infrared spectroscopy EPR fluorescence transfer theoretical model Hybrid
Author
Journal
IF	>30 >20 >10 >5 all

Title	Cryo-EM structures of light-harvesting 2 complexes from reveal the molecular origin of absorption tuning.
Journal, issue, pages	Proc Natl Acad Sci U S A, Vol. 119, Issue 43, Page e2210109119, Year 2022
Publish date	Oct 25, 2022
Authors	Pu Qian / Cam T Nguyen-Phan / Alastair T Gardiner / Tristan I Croll / Aleksander W Roszak / June Southall / Philip J Jackson / Cvetelin Vasilev / Pablo Castro-Hartmann / Kasim Sader / C Neil Hunter / Richard J Cogdell /
PubMed Abstract	The genomes of some purple photosynthetic bacteria contain a multigene family encoding a series of α- and β-polypeptides that together form a heterogeneous antenna of light-harvesting 2 (LH2) ...The genomes of some purple photosynthetic bacteria contain a multigene family encoding a series of α- and β-polypeptides that together form a heterogeneous antenna of light-harvesting 2 (LH2) complexes. To unravel this complexity, we generated four sets of deletion mutants in , each encoding a single type of gene pair and enabling the purification of complexes designated as PucA-LH2, PucB-LH2, PucD-LH2, and PucE-LH2. The structures of all four purified LH2 complexes were determined by cryogenic electron microscopy (cryo-EM) at resolutions ranging from 2.7 to 3.6 Å. Uniquely, each of these complexes contains a hitherto unknown polypeptide, γ, that forms an extended undulating ribbon that lies in the plane of the membrane and that encloses six of the nine LH2 αβ-subunits. The γ-subunit, which is located near to the cytoplasmic side of the complex, breaks the C9 symmetry of the LH2 complex and binds six extra bacteriochlorophylls (BChls) that enhance the 800-nm absorption of each complex. The structures show that all four complexes have two complete rings of BChls, conferring absorption bands centered at 800 and 850 nm on the PucA-LH2, PucB-LH2, and PucE-LH2 complexes, but, unusually, the PucD-LH2 antenna has only a single strong near-infared (NIR) absorption peak at 803 nm. Comparison of the cryo-EM structures of these LH2 complexes reveals altered patterns of hydrogen bonds between LH2 αβ-side chains and the bacteriochlorin rings, further emphasizing the major role that H bonds play in spectral tuning of bacterial antenna complexes.
External links	Proc Natl Acad Sci U S A / PubMed:36251992 / PubMed Central
Methods	EM (single particle)
Resolution	2.7 - 3.6 Å
Structure data	14633 7zcu EMDB-14633, PDB-7zcu: PucA-LH2 complex from Rps. palustris Method: EM (single particle) / Resolution: 2.7 Å 14650 7zdi EMDB-14650, PDB-7zdi: PucB-LH2 complex from Rps. palustris Method: EM (single particle) / Resolution: 2.9 Å 14682 7ze3 EMDB-14682, PDB-7ze3: PucD-LH2 complex from Rps. palustris Method: EM (single particle) / Resolution: 2.7 Å 14685 7ze8 EMDB-14685, PDB-7ze8: PucE-LH2 complex from Rps. palustris Method: EM (single particle) / Resolution: 3.6 Å
Chemicals	ChemComp-BCL: BACTERIOCHLOROPHYLL A ChemComp-IRM: 1,2-Dihydro-psi,psi-caroten-1-ol ChemComp-HOH: WATER ChemComp-ZE0: (3'E)-3',4'-didehydro-1,2-dihydro-psi,psi-caroten-1-ol
Source	rhodopseudomonas palustris atcc 17001 (phototrophic) rhodopseudomonas palustris (phototrophic)
Keywords	PHOTOSYNTHESIS / light harvesting complex 2 / LH2 / Rps. palustris / purple bacteria / cryo-EM / single particle analysis