We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Energy transfer in Anabaena variabilis filaments adapted to nitrogen-depleted and nitrogen-enriched conditions studied by time-resolved fluorescence.
- Authors
Onishi, Aya; Aikawa, Shimpei; Kondo, Akihiko; Akimoto, Seiji
- Abstract
Nitrogen is among the most important nutritious elements for photosynthetic organisms such as plants, algae, and cyanobacteria. Therefore, nitrogen depletion severely compromises the growth, development, and photosynthesis of these organisms. To preserve their integrity under nitrogen-depleted conditions, filamentous nitrogen-fixing cyanobacteria reduce atmospheric nitrogen to ammonia, and self-adapt by regulating their light-harvesting and excitation energy-transfer processes. To investigate the changes in the primary processes of photosynthesis, we measured the steady-state absorption and fluorescence spectra and time-resolved fluorescence spectra (TRFS) of whole filaments of the nitrogen-fixing cyanobacterium Anabaena variabilis at 77 K. The filaments were grown in standard and nitrogen-free media for 6 months. The TRFS were measured with a picosecond time-correlated single photon counting system. Despite the phycobilisome degradation, the energy-transfer paths within phycobilisome and from phycobilisome to both photosystems were maintained. However, the energy transfer from photosystem II to photosystem I was suppressed and a specific red chlorophyll band appeared under the nitrogen-depleted condition.
- Subjects
ANABAENA variabilis; ENERGY transfer; NITROGEN-fixing cyanobacteria; NITROGEN reduction; NITROGEN content of plants
- Publication
Photosynthesis Research, 2017, Vol 133, Issue 1-3, p317
- ISSN
0166-8595
- Publication type
Article
- DOI
10.1007/s11120-017-0352-4