Association of chlorophyll a/c(2) complexes to photosystem I and photosystem II in the cryptophyte Rhodomonas CS24.
Photosynthetic supercomplexes from the cryptophyte Rhodomonas CS24 were isolated by a short detergent treatment of membranes from the cryptophyte Rhodomonas CS24 and studied by electron microscopy and low-temperature absorption and fluorescence spectroscopy. At least three different types of supercomplexes of photosystem I (PSI) monomers and peripheral Chl a/c(2) proteins were found. The most common complexes have Chl a/c(2) complexes at both sides of the PSI core monomer and have dimensions of about 17x24 nm. The peripheral antenna in these supercomplexes shows no obvious similarities in size and/or shape with that of the PSI-LHCI supercomplexes from the green plant Arabidopsis thaliana and the green alga Chlamydomonas reinhardtii, and may be comprised of about 6-8 monomers of Chl a/c(2) light-harvesting complexes. In addition, two different types of supercomplexes of photosystem II (PSII) dimers and peripheral Chl a/c(2) proteins were found. The detected complexes consist of a PSII core dimer and three or four monomeric Chl a/c(2) proteins on one side of the PSII core at positions that in the largest complex are similar to those of Lhcb5, a monomer of the S-trimer of LHCII, Lhcb4 and Lhcb6 in green plants.
Department of Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Sami
S
Kereïche
Roman
R
Kouril
Gert T
GT
Oostergetel
Fabrizia
F
Fusetti
Egbert J
EJ
Boekema
Alexander B
AB
Doust
Chantal D
CD
van der Weij-de Wit
Jan P
JP
Dekker
D002734:Chlorophyll / Q000378:metabolism*; D000077194:Chlorophyll A; D002850:Chromatography, Gel; D044785:Cryptophyta / Q000378:metabolism*; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D013058:Mass Spectrometry; D008854:Microscopy, Electron; D045331:Photosystem I Protein Complex / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D045332:Photosystem II Protein Complex / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D013057:Spectrum Analysis; D013696:Temperature
D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D002734:Chlorophyll; C064041:chlorophyll c; D000077194:Chlorophyll A