Photosystem I at 4 Å resolution represents the first structural model of a joint photosynthetic reaction centre and core antenna system
- 1 November 1996
- journal article
- research article
- Published by Springer Nature in Nature Structural & Molecular Biology
- Vol. 3 (11) , 965-973
- https://doi.org/10.1038/nsb1196-965
Abstract
The 4 Å X-ray structure model of trimeric photosystem I of the cyanobacterium Synechococcus elongatus reveals 31 transmembrane, nine surface and three stromal α-helices per monomer, assigned to the 11 protein subunits: PsaA and PsaB are related by a pseudo two-fold axis normal to the membrane plane, along which the electron transfer pigments are arranged. 65 antenna chlorophyll a (Chl a) molecules separated by ≤16 Å form an oval, clustered net, continuous with the electron transfer chain through the second and third Chl a pairs of the electron transfer system. This suggests a dual role for these Chl a both in excitation energy and electron transfer. The architecture of the protein core indicates quinone and iron-sulphur type reaction centres to have a common ancestor.Keywords
This publication has 54 references indexed in Scilit:
- Genes encoding eleven subunits of photosystem I from the thermophilic cyanobacterium Synechococcus sp.Gene, 1993
- Site-directed conversion of a cysteine to aspartate leads to the assembly of a N iron-sulfur[3Fe-4S] cluster to PsaC of photosystem I. The photoreduction of FA is independent of FBBiochemistry, 1992
- Structure of the membrane-bound protein photosynthetic reaction center from Rhodobacter sphaeroidesBiochemistry, 1991
- Mono-, di- and trimeric PS I reaction center complexes isolated from the thermophilic cyanobacterium Synechococcus sp.: Size, shape and activityBiochimica et Biophysica Acta (BBA) - Bioenergetics, 1990
- New assignment for the 250 μs kinetics in Photosystem I: P-700+ recombines with A−1 (not F−x)Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1989
- Identification of the plastocyanin binding subunit of photosystem IFEBS Letters, 1989
- Isolation of the intact photosystem I reaction center core containing P700 and iron‐sulfur center FXFEBS Letters, 1988
- The 8 kDa polypeptide in photosystem I is a probable candidate of an iron‐sulfur center protein coded by the chloroplast gene frxAFEBS Letters, 1987
- Preliminary characterization by X-ray diffraction of crystals of photochemical reaction centres from wild-type Rhodopseudomonas spheroidsJournal of Molecular Biology, 1987
- Function of the Two Cytochrome Components in Chloroplasts: A Working HypothesisNature, 1960