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Updated: Jun 10, 2026

Isolation and Characterization of Intact Phycobilisome in Cyanobacteria
Published on: November 10, 2021
Structure of CyanoP at 2.8 A: implications for the evolution and function of the PsbP subunit of photosystem II
Franck Michoux1, Kenji Takasaka, Marko Boehm
1Division of Biology, Wolfson Biochemistry Building, Imperial College London,South Kensington Campus, London SW7 2AZ, UK.
Abstract:
We present here the crystal structure of CyanoP (Tlr2075) from Thermosynechococcus elongatus at 2.8 A. CyanoP is a substoichiometric component of the isolated cyanobacterial Photosystem II (PSII) complex, distantly related to the PsbP extrinsic subunit of the oxygen-evolving PSII complex in higher plants and green algae. Despite the relatively low degree of sequence similarity, we have found that CyanoP adopts the same beta-sandwich fold as higher-plant PsbP and contains a well-conserved metal (zinc)-binding site that is also present in plant PsbP. Our results support the idea that CyanoP represents the basal structural fold of the PsbP superfamily.
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