Send to

Choose Destination
See comment in PubMed Commons below
Structure. 2009 May 13;17(5):637-50. doi: 10.1016/j.str.2009.03.006.

Plant photosystem I design in the light of evolution.

Author information

  • 1Biochemistry Department, George S Wise Faculty of Life Sciences, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv, Israel.


Photosystem I (PSI) is a membrane protein complex that catalyzes sunlight-driven transmembrane electron transfer as part of the photosynthetic machinery. Photosynthetic organisms appeared on the Earth about 3.5 billion years ago and provided an essential source of potential energy for the development of life. During the course of evolution, these primordial organisms were phagocytosed by more sophisticated eukaryotic cells, resulting in the evolvement of algae and plants. Despite the extended time interval between primordial cyanobacteria and plants, PSI has retained its fundamental mechanism of sunlight conversion. Being probably the most efficient photoelectric apparatus in nature, PSI operates with a quantum efficiency close to 100%. However, adapting to different ecological niches necessitated structural changes in the PSI design. Based on the recently solved structure of plant PSI, which revealed a complex of 17 protein subunits and 178 prosthetic groups, we analyze the evolutionary development of PSI. In addition, some aspects of PSI structure determination are discussed.

[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center