6KMX

Structure of PSI from H. hongdechloris grown under far-red light condition

This is a non-PDB format compatible entry.

Summary for 6KMX

• Entry DOI: 10.2210/pdb6kmx/pdb
• Related: 6KMW
• EMDB information: 0727
• Descriptor: Photosystem I P700 chlorophyll a apoprotein A1, CHLOROPHYLL A ISOMER, CHLOROPHYLL A, ... (21 entities in total)
• Functional Keywords: photosystem i, electron transport
• Biological source: Halomicronema hongdechloris C2206; More
• Total number of polymer chains: 27
• Total formula weight: 1011731.07

Authors

Kato, K.,Nagao, R.,Shen, J.R.,Miyazaki, N.,Akita, F. (deposition date: 2019-08-01, release date: 2020-01-15, Last modification date: 2024-03-27)

Primary citation

Kato, K.,Shinoda, T.,Nagao, R.,Akimoto, S.,Suzuki, T.,Dohmae, N.,Chen, M.,Allakhverdiev, S.I.,Shen, J.R.,Akita, F.,Miyazaki, N.,Tomo, T.
Structural basis for the adaptation and function of chlorophyll f in photosystem I.
Nat Commun, 11:238-238, 2020

PubMed Abstract: Chlorophylls (Chl) play pivotal roles in energy capture, transfer and charge separation in photosynthesis. Among Chls functioning in oxygenic photosynthesis, Chl f is the most red-shifted type first found in a cyanobacterium Halomicronema hongdechloris. The location and function of Chl f in photosystems are not clear. Here we analyzed the high-resolution structures of photosystem I (PSI) core from H. hongdechloris grown under white or far-red light by cryo-electron microscopy. The structure showed that, far-red PSI binds 83 Chl a and 7 Chl f, and Chl f are associated at the periphery of PSI but not in the electron transfer chain. The appearance of Chl f is well correlated with the expression of PSI genes induced under far-red light. These results indicate that Chl f functions to harvest the far-red light and enhance uphill energy transfer, and changes in the gene sequences are essential for the binding of Chl f.

PubMed: 31932639
DOI: 10.1038/s41467-019-13898-5

Experimental method

ELECTRON MICROSCOPY (2.41 Å)