Cryo-imaging of photosystems and phycobilisomes in Anabaena sp. PCC 7120 cells
Language English Country Switzerland Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't
PubMed
26498711
DOI
10.1016/j.jphotobiol.2015.10.003
PII: S1011-1344(15)00324-3
Knihovny.cz E-resources
- Keywords
- Confocal microscopy, Cryogenic microscopy, Cyanobacteria, Membrane domains, Photosynthesis,
- MeSH
- Anabaena cytology enzymology metabolism MeSH
- Photosystem I Protein Complex chemistry metabolism MeSH
- Photosystem II Protein Complex chemistry metabolism MeSH
- Phycobilisomes chemistry metabolism MeSH
- Microscopy, Confocal * MeSH
- Protein Conformation MeSH
- Models, Molecular MeSH
- Protein Transport MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Photosystem I Protein Complex MeSH
- Photosystem II Protein Complex MeSH
- Phycobilisomes MeSH
Primary photosynthetic reactions take place inside thylakoid membrane where light-to-chemical energy conversion is catalyzed by two pigment-protein complexes, photosystem I (PSI) and photosystem II (PSII). Light absorption in cyanobacteria is increased by pigment-protein supercomplexes--phycobilisomes (PBSs) situated on thylakoid membrane surfaces that transfer excitation energy into both photosystems. We have explored the localization of PSI, PSII and PBSs in thylakoid membrane of native cyanobacteria cell Anabaena sp. 7120 by means of cryogenic confocal microscopy. We have adapted a conventional temperature controlling stage to an Olympus FV1000 confocal microscope. The presence of red shifted emission of chlorophylls from PSI has been confirmed by spectral measurements. Confocal fluorescence images of PSI (in a spectral range 710-750 nm), PSII (in a spectral range 690-705 nm) and PBSs (in a spectral range 650-680 nm) were recorded at low temperature. Co-localization of images showed spatial heterogeneity of PSI, PSII and PBSs over the thylakoid membrane, and three dominant areas were identified: PSI-PSII-PBS supercomplex area, PSII-PBS supercomplex area and PSI area. The observed results were discussed with regard to light-harvesting regulation in cyanobacteria.
References provided by Crossref.org
Fast Diffusion of the Unassembled PetC1-GFP Protein in the Cyanobacterial Thylakoid Membrane
