|1qzv, resolution 4.44Å ()|
Crystal structure of plant photosystem I
Oxygenic photosynthesis is the principal producer of both oxygen and organic matter on Earth. The conversion of sunlight into chemical energy is driven by two multisubunit membrane protein complexes named photosystem I and II. We determined the crystal structure of the complete photosystem I (PSI) from a higher plant (Pisum sativum var. alaska) to 4.4 A resolution. Its intricate structure shows 12 core subunits, 4 different light-harvesting membrane proteins (LHCI) assembled in a half-moon shape on one side of the core, 45 transmembrane helices, 167 chlorophylls, 3 Fe-S clusters and 2 phylloquinones. About 20 chlorophylls are positioned in strategic locations in the cleft between LHCI and the core. This structure provides a framework for exploration not only of energy and electron transfer but also of the evolutionary forces that shaped the photosynthetic apparatus of terrestrial plants after the divergence of chloroplasts from marine cyanobacteria one billion years ago.
Crystal structure of plant photosystem I., Ben-Shem A, Frolow F, Nelson N, Nature. 2003 Dec 11;426(6967):630-5. PMID:14668855
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
About this Structure
- Ben-Shem A, Frolow F, Nelson N. Crystal structure of plant photosystem I. Nature. 2003 Dec 11;426(6967):630-5. PMID:14668855 doi:10.1038/nature02200
- Kiley P, Zhao X, Vaughn M, Baldo MA, Bruce BD, Zhang S. Self-assembling peptide detergents stabilize isolated photosystem I on a dry surface for an extended time. PLoS Biol. 2005 Jul;3(7):e230. Epub 2005 Jun 21. PMID:15954800 doi:10.1371/journal.pbio.0030230