Novel supercomplex organization of photosystem I in Anabaena and Cyanophora paradoxa.
The supercomplex organization of photosystem complexes was studied in various cyanobacteria, a glaucocystophyte and a primitive rhodophyte by blue-native PAGE with a wide range of detergent concentrations. In contrast to known cyanobacteria that produced the PSI trimer, a filamentous N(2)-fixing cyanobacterium Anabaena sp. PCC 7120 and a glaucocystophyte Cyanophora paradoxa NIES 547 had a PSI tetramer and dimer but no trimer at all. This was confirmed by sucrose density gradient centrifugation. A primitive rhodophyte Cyanidioschyzon merolae had two species of PSI monomeric complex with a light-harvesting Chl complex of a different composition. These results are discussed with regard to the evolution of the PSI supercomplex.
Department of Life Sciences, University of Tokyo, Komaba, Meguro, Tokyo, Japan.
Mai
M
Watanabe
Hisako
H
Kubota
Hajime
H
Wada
Rei
R
Narikawa
Masahiko
M
Ikeuchi
D017033:Anabaena / Q000378:metabolism*; D002498:Centrifugation; D044424:Cyanophora / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D045331:Photosystem I Protein Complex / Q000378:metabolism*
D045331:Photosystem I Protein Complex