6UZV

The structure of a red shifted photosystem I complex

Summary for 6UZV

• Entry DOI: 10.2210/pdb6uzv/pdb
• EMDB information: 20963
• Descriptor: Photosystem I P700 chlorophyll a apoprotein A1, Photosystem I reaction center subunit XII, Photosystem I reaction center subunit PsaK 2, ... (20 entities in total)
• Functional Keywords: photosystem, antenna, chlorophyll, membrane, photosynthesis
• Biological source: Synechocystis sp. (strain PCC 6803 / Kazusa); More
• Total number of polymer chains: 33
• Total formula weight: 1086839.85

Authors

Toporik, H.,Williams, D.,Chiu, P.L.,Mazor, Y. (deposition date: 2019-11-15, release date: 2020-09-16, Last modification date: 2024-10-30)

Primary citation

Toporik, H.,Khmelnitskiy, A.,Dobson, Z.,Riddle, R.,Williams, D.,Lin, S.,Jankowiak, R.,Mazor, Y.
The structure of a red-shifted photosystem I reveals a red site in the core antenna.
Nat Commun, 11:5279-5279, 2020

PubMed Abstract: Photosystem I coordinates more than 90 chlorophylls in its core antenna while achieving near perfect quantum efficiency. Low energy chlorophylls (also known as red chlorophylls) residing in the antenna are important for energy transfer dynamics and yield, however, their precise location remained elusive. Here, we construct a chimeric Photosystem I complex in Synechocystis PCC 6803 that shows enhanced absorption in the red spectral region. We combine Cryo-EM and spectroscopy to determine the structurefunction relationship in this red-shifted Photosystem I complex. Determining the structure of this complex reveals the precise architecture of the low energy site as well as large scale structural heterogeneity which is probably universal to all trimeric Photosystem I complexes. Identifying the structural elements that constitute red sites can expand the absorption spectrum of oxygenic photosynthetic and potentially modulate light harvesting efficiency.

PubMed: 33077842
DOI: 10.1038/s41467-020-18884-w

Experimental method

ELECTRON MICROSCOPY (3.1 Å)