Abstract
Cyanobacteria carry out photosynthetic light-energy conversion using phycobiliproteins for light harvesting and the chlorophyll-rich photosystems for photochemistry. While most cyanobacteria only absorb visible photons, some of them can acclimate to harvest far-red light (FRL, 700–800 nm) by integrating chlorophyll f and d in their photosystems and producing red-shifted allophycocyanin. Chlorophyll f insertion enables the photosystems to use FRL but slows down charge separation, reducing photosynthetic efficiency. Here we demonstrate with time-resolved fluorescence spectroscopy that on average charge separation in chlorophyll-f-containing Photosystem II becomes faster in the presence of red-shifted allophycocyanin antennas. This is different from all known photosynthetic systems, where additional light-harvesting complexes increase the overall absorption cross section but slow down charge separation. This remarkable property can be explained with the available structural and spectroscopic information. The unique design is probably important for these cyanobacteria to efficiently switch between visible and far-red light.
| Original language | English |
|---|---|
| Article number | 3562 |
| Pages (from-to) | 1-8 |
| Number of pages | 8 |
| Journal | Nature Communications |
| Volume | 13 |
| DOIs | |
| Publication status | Published - 21 Jun 2022 |
Bibliographical note
Funding Information:This project was supported by by the Netherlands Organization for Scientific Research (NWO) via a Top grant to R.C. and the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no. 675006 (to H.v.A. and R.C.). L.B. was supported by an EMBO long-term fellowship (EMBO ALTF 292-2017).
Publisher Copyright:
© 2022, The Author(s).
Funding
This project was supported by by the Netherlands Organization for Scientific Research (NWO) via a Top grant to R.C. and the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no. 675006 (to H.v.A. and R.C.). L.B. was supported by an EMBO long-term fellowship (EMBO ALTF 292-2017).
