6MEM

A unique supramolecular organization of photosystem I in the moss Physcomitrella patens

Summary for 6MEM

• Entry DOI: 10.2210/pdb6mem/pdb
• EMDB information: 9107
• Descriptor: Chlorophyll A/B binding protein 1, PsaA, Chlorophyll A/B binding protein 10, ... (24 entities in total)
• Functional Keywords: photosynthesis, complex, photosystem i, light harvesting complex, physcomitrella
• Biological source: Physcomitrella patens; More
• Total number of polymer chains: 24
• Total formula weight: 420509.28

Authors

Iwai, M.,Grob, P. (deposition date: 2018-09-06, release date: 2018-11-21, Last modification date: 2024-03-13)

Primary citation

Iwai, M.,Grob, P.,Iavarone, A.T.,Nogales, E.,Niyogi, K.K.
A unique supramolecular organization of photosystem I in the moss Physcomitrella patens.
Nat Plants, 4:904-909, 2018

PubMed Abstract: The photosynthesis machinery in chloroplast thylakoid membranes is comprised of multiple protein complexes and supercomplexes. Here, we show a novel supramolecular organization of photosystem I (PSI) in the moss Physcomitrella patens by single-particle cryo-electron microscopy. The moss-specific light-harvesting complex (LHC) protein Lhcb9 is involved in this PSI supercomplex, which has been shown to have a molecular density similar to that of the green alga Chlamydomonas reinhardtii. Our results show that the structural organization is unexpectedly different-two rows of the LHCI belt exist as in C. reinhardtii, but the outer one is shifted toward the PsaK side. Furthermore, one trimeric LHC protein and one monomeric LHC protein position alongside PsaL/K, filling the gap between these subunits and the outer LHCI belt. We provide evidence showing that Lhcb9 is a key factor, acting as a linkage between the PSI core and the outer LHCI belt to form the unique supramolecular organization of the PSI supercomplex in P. patens.

PubMed: 30374090
DOI: 10.1038/s41477-018-0271-1

Experimental method

ELECTRON MICROSCOPY (11.6 Å)