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Energy transfer from phycobilisomes to photosystem I at room temperature.

ABSTRACT: The phycobilisomes function as the primary light-harvesting antennae in cyanobacteria and red algae, effectively harvesting and transferring excitation energy to both photosystems. Here we investigate the direct energy transfer route from the phycobilisomes to photosystem I at room temperature in a mutant of the cyanobacterium Synechocystis sp. PCC 6803 that lacks photosystem II. The excitation dynamics are studied by picosecond time-resolved fluorescence measurements in combination with global and target analysis. Global analysis revealed several fast equilibration time scales and a decay of the equilibrated system with a time constant of ≈220 ps. From simultaneous target analysis of measurements with two different excitations of 400 nm (chlorophyll a) and 580 nm (phycobilisomes) a transfer rate of 42 ns^-1 from the terminal emitter of the phycobilisome to photosystem I was estimated.

SUBMITTER: Biswas A

PROVIDER: S-EPMC10800844 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature

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Energy transfer from phycobilisomes to photosystem I at room temperature.

Biswas Avratanu A Akhtar Parveen P Lambrev Petar H PH van Stokkum Ivo H M IHM

Frontiers in plant science 20240108

The phycobilisomes function as the primary light-harvesting antennae in cyanobacteria and red algae, effectively harvesting and transferring excitation energy to both photosystems. Here we investigate the direct energy transfer route from the phycobilisomes to photosystem I at room temperature in a mutant of the cyanobacterium <i>Synechocystis</i> sp. PCC 6803 that lacks photosystem II. The excitation dynamics are studied by picosecond time-resolved fluorescence measurements in combination with ...[more]

PMID: 38259910

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