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Updated: Jun 6, 2026

Isolation and Characterization of Intact Phycobilisome in Cyanobacteria
Published on: November 10, 2021
Novel supercomplex organization of photosystem I in Anabaena and Cyanophora paradoxa
Mai Watanabe1, Hisako Kubota, Hajime Wada
1Department of Life Sciences, University of Tokyo, Komaba, Meguro, Tokyo, Japan.
Abstract:
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.
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