5LCB

In situ atomic-resolution structure of the baseplate antenna complex in Chlorobaculum tepidum obtained combining solid-state NMR spectroscopy, cryo electron microscopy and polarization spectroscopy

Summary for 5LCB

• Entry DOI: 10.2210/pdb5lcb/pdb
• EMDB information: 4033
• NMR Information: BMRB: 34012
• Descriptor: Bacteriochlorophyll c-binding protein, BACTERIOCHLOROPHYLL A (2 entities in total)
• Functional Keywords: photosynthesis, light-harvesting protein, binds bacteriochlorophyll a, oligomeric complex, bacteriochlorophyll binding protein
• Biological source: Chlorobium tepidum (strain ATCC 49652 / DSM 12025 / NBRC 103806 / TLS)
• Total number of polymer chains: 14
• Total formula weight: 99001.53

Authors

Nielsen, J.T.,Kulminskaya, N.V.,Bjerring, M.,Linnanto, J.M.,Ratsep, M.,Pedersen, M.,Lambrev, P.H.,Dorogi, M.,Garab, G.,Thomsen, K.,Jegerschold, C.,Frigaard, N.U.,Lindahl, M.,Nielsen, N.C. (deposition date: 2016-06-20, release date: 2016-07-27, Last modification date: 2025-05-07)

Primary citation

Nielsen, J.T.,Kulminskaya, N.V.,Bjerring, M.,Linnanto, J.M.,Ratsep, M.,Pedersen, M.O.,Lambrev, P.H.,Dorogi, M.,Garab, G.,Thomsen, K.,Jegerschold, C.,Frigaard, N.U.,Lindahl, M.,Nielsen, N.C.
In situ high-resolution structure of the baseplate antenna complex in Chlorobaculum tepidum.
Nat Commun, 7:12454-12454, 2016

PubMed Abstract: Photosynthetic antenna systems enable organisms harvesting light and transfer the energy to the photosynthetic reaction centre, where the conversion to chemical energy takes place. One of the most complex antenna systems, the chlorosome, found in the photosynthetic green sulfur bacterium Chlorobaculum (Cba.) tepidum contains a baseplate, which is a scaffolding super-structure, formed by the protein CsmA and bacteriochlorophyll a. Here we present the first high-resolution structure of the CsmA baseplate using intact fully functional, light-harvesting organelles from Cba. tepidum, following a hybrid approach combining five complementary methods: solid-state NMR spectroscopy, cryo-electron microscopy, isotropic and anisotropic circular dichroism and linear dichroism. The structure calculation was facilitated through development of new software, GASyCS for efficient geometry optimization of highly symmetric oligomeric structures. We show that the baseplate is composed of rods of repeated dimers of the strongly amphipathic CsmA with pigments sandwiched within the dimer at the hydrophobic side of the helix.

PubMed: 27534696
DOI: 10.1038/ncomms12454

Experimental method

ELECTRON MICROSCOPY (26.5 Å)
SOLID-STATE NMR (26.5 Å)