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Updated: Aug 17, 2026

Isolation and Characterization of Intact Phycobilisome in Cyanobacteria
Published on: November 10, 2021
Structure of cyanobacterial photosystem I
Ingo Grotjohann1, Petra Fromme
1Arizona State University, Tempe, AZ, 85287-1604, USA.
Abstract:
Photosystem I is one of the most fascinating membrane protein complexes for which a structure has been determined. It functions as a bio-solar energy converter, catalyzing one of the first steps of oxygenic photosynthesis. It captures the light of the sun by means of a large antenna system, consisting of chlorophylls and carotenoids, and transfers the energy to the center of the complex, driving the transmembrane electron transfer from plastoquinone to ferredoxin. Cyanobacterial Photosystem I is a trimer consisting of 36 proteins to which 381 cofactors are non-covalently attached. This review discusses the complex function of Photosystem I based on the structure of the complex at 2.5 A resolution as well as spectroscopic and biochemical data.
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