Open AccessThree‐dimensional structure of the higher‐plant photosystem II reaction centre and evidence for its dimeric organization in vivo
Author(s) -
SANTINI Caterina,
TIDU Valentino,
TOG Giuseppe,
GHIRETTI MAGALDI Anna,
BASSI Roberto
Publication year - 1994
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1994.tb18742.x
Subject(s) - photosystem ii , oxygen evolving complex , protein subunit , transmission electron microscopy , chemistry , biophysics , crystallography , photosynthetic reaction centre , photosystem i , electron microscope , photochemistry , biology , photosynthesis , materials science , biochemistry , electron transfer , nanotechnology , optics , physics , gene
The three‐dimensional structure of photosystem II (PSII) has been determined by conventional transmission electron microscopy and computerized three‐dimensional reconstruction. Both the complete system and that lacking the oxygen‐evolving complex have been analyzed. The PSII complex has a four‐lobed structure with twofold symmetry. An estimate of the molecular mass and the results of Deriphat/PAGE analysis suggest that a reaction centre is present in each half of the structure resolved by electron microscopy. Stepwise removal of components of the complex showed that the removal of CP47 (a 47‐kDa chlorophyll‐protein complex) induces monomerization of PSII, which indicates the importance of this subunit for the dimeric structure.