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Updated: Jun 26, 2026

Isolation and Characterization of Intact Phycobilisome in Cyanobacteria
Published on: November 10, 2021
The dynamic behavior of phycobilisome movement during light state transitions in cyanobacterium Synechocystis PCC6803
Shuzhen Yang1, Rui Zhang, Changchao Hu
1Beijing National Laboratory for Molecular Sciences (BNLMS), Photochemistry Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing, People's Republic of China.
Abstract:
Light state transition is a physiological function of oxygenic organisms to balance the excitation of photosystem II (PSII) and photosystem I (PSI), hence a prerequisite of oxygen-evolving photosynthesis. For cyanobacteria, phycobilisome (PBS) movement during light state transition has long been expected, but never observed. Here the dynamic behavior of PBS movement during state transition in cyanobacterium Synechocystis PCC6803 is experimentally detected via time-dependent fluorescence fluctuation. Under continuous excitation of PBSs in the intact cells, time-dependent fluorescence fluctuations resemble "damped oscillation" mode, which indicates dynamic searching of a PBS in an "overcorrection" manner for the "balance" position where PSII and PSI are excited equally. Based on the parallel model, it is suggested that the "damped oscillation" fluorescence fluctuation is originated from a collective movement of all the PBSs to find the "balance" position. Based on the continuous fluorescence fluctuation during light state transition and also variety of solar spectra, it may be deduced that light state transition of oxygen-evolution organisms is a natural behavior that occurs daily rather than an artificial phenomenon at extreme light conditions in laboratory.
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