6YXR

Dunaliella Minimal Photosystem I

Summary for 6YXR

• Entry DOI: 10.2210/pdb6yxr/pdb
• Related: 6rhz
• EMDB information: 10995
• Descriptor: Chlorophyll a-b binding protein, chloroplastic, PsaF, Photosystem I reaction center subunit IX, ... (23 entities in total)
• Functional Keywords: membrane complex, photosystem i, dunaliella, light harvesting, excitation transfer, photosynthesis
• Biological source: Dunaliella salina (Green alga); More
• Total number of polymer chains: 11
• Total formula weight: 466243.70

Authors

Nelson, N.,Caspy, I.,Malavath, T.,Klaiman, D.,Shkolinsky, Y. (deposition date: 2020-05-03, release date: 2020-07-01, Last modification date: 2024-10-16)

Primary citation

Caspy, I.,Malavath, T.,Klaiman, D.,Fadeeva, M.,Shkolnisky, Y.,Nelson, N.
Structure and energy transfer pathways of the Dunaliella Salina photosystem I supercomplex.
Biochim Biophys Acta Bioenerg, 1861:148253-148253, 2020

PubMed Abstract: Oxygenic photosynthesis evolved more than 3 billion years ago in cyanobacteria. The increased complexity of photosystem I (PSI) became apparent from the high-resolution structures that were obtained for the complexes that were isolated from various organisms, ranging from cyanobacteria to plants. These complexes are all evolutionarily linked. In this paper, the researchers have uncovered the increased complexity of PSI in a single organism demonstrated by the coexistance of two distinct PSI compositions. The Large Dunaliella PSI contains eight additional subunits, six in PSI core and two light harvesting complexes. Two additional chlorophyll a molecules pertinent for efficient excitation energy transfer in state II transition were identified in PsaL and PsaO. Short distances between these newly identified chlorophylls correspond with fast excitation transfer rates previously reported during state II transition. The apparent PSI conformations could be a coping mechanism for the high salinity.

PubMed: 32569661
DOI: 10.1016/j.bbabio.2020.148253

Experimental method

ELECTRON MICROSCOPY (3.4 Å)