We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
The structural basis for light acclimation in phycobilisome light harvesting systems systems in Porphyridium purpureum.
- Authors
Dodson, Emma Joy; Ma, Jianfei; Suissa Szlejf, Maayan; Maroudas-Sklare, Naama; Paltiel, Yossi; Adir, Noam; Sun, Shan; Sui, Sen-Fang; Keren, Nir
- Abstract
Photosynthetic organisms adapt to changing light conditions by manipulating their light harvesting complexes. Biophysical, biochemical, physiological and genetic aspects of these processes are studied extensively. The structural basis for these studies is lacking. In this study we address this gap in knowledge by focusing on phycobilisomes (PBS), which are large structures found in cyanobacteria and red algae. In this study we focus on the phycobilisomes (PBS), which are large structures found in cyanobacteria and red algae. Specifically, we examine red algae (Porphyridium purpureum) grown under a low light intensity (LL) and a medium light intensity (ML). Using cryo-electron microscopy, we resolve the structure of ML-PBS and compare it to the LL-PBS structure. The ML-PBS is 13.6 MDa, while the LL-PBS is larger (14.7 MDa). The LL-PBS structure have a higher number of closely coupled chromophore pairs, potentially the source of the red shifted fluorescence emission from LL-PBS. Interestingly, these differences do not significantly affect fluorescence kinetics parameters. This indicates that PBS systems can maintain similar fluorescence quantum yields despite an increase in LL-PBS chromophore numbers. These findings provide a structural basis to the processes by which photosynthetic organisms adapt to changing light conditions. Cryo-EM examination of phycobilisomes from red algae reveal light-induced structural changes and chromophore variations that have limited effects on fluorescence kinetics, providing insight into how photosynthetic organisms adapt to changing light conditions.
- Subjects
FLUORESCENCE yield; RED algae; LIGHT intensity; PHYCOBILISOMES; ACCLIMATIZATION; REDSHIFT
- Publication
Communications Biology, 2023, Vol 6, Issue 1, p1
- ISSN
2399-3642
- Publication type
Article
- DOI
10.1038/s42003-023-05586-4