Helical allophycocyanin nanotubes absorb far-red light in a thermophilic cyanobacterium
| Autor: | Christopher J. Gisriel, Eduard Elias, Gaozhong Shen, Nathan T. Soulier, David A. Flesher, M. R. Gunner, Gary W. Brudvig, Roberta Croce, Donald A. Bryant |
|---|---|
| Přispěvatelé: | Biophysics Photosynthesis/Energy, LaserLaB - Energy |
| Jazyk: | angličtina |
| Rok vydání: | 2023 |
| Předmět: | |
| Zdroj: | Science advances, 9(12):eadg0251, 1-12. American Association for the Advancement of Science Science advances, vol 9, iss 12 Gisriel, C J, Elias, E, Shen, G, Soulier, N T, Flesher, D A, Gunner, M R, Brudvig, G W, Croce, R & Bryant, D A 2023, ' Helical allophycocyanin nanotubes absorb far-red light in a thermophilic cyanobacterium ', Science advances, vol. 9, no. 12, eadg0251, pp. 1-12 . https://doi.org/10.1126/sciadv.adg0251 |
| ISSN: | 2375-2548 |
| DOI: | 10.1126/sciadv.adg0251 |
| Popis: | To compete in certain low-light environments, some cyanobacteria express a paralog of the light-harvesting phycobiliprotein, allophycocyanin (AP), that strongly absorbs far-red light (FRL). Using cryo–electron microscopy and time-resolved absorption spectroscopy, we reveal the structure-function relationship of this FRL-absorbing AP complex (FRL-AP) that is expressed during acclimation to low light and that likely associates with chlorophyll a–containing photosystem I. FRL-AP assembles as helical nanotubes rather than typical toroids due to alterations of the domain geometry within each subunit. Spectroscopic characterization suggests that FRL-AP nanotubes are somewhat inefficient antenna; however, the enhanced ability to harvest FRL when visible light is severely attenuated represents a beneficial trade-off. The results expand the known diversity of light-harvesting proteins in nature and exemplify how biological plasticity is achieved by balancing resource accessibility with efficiency. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|