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Conformational dynamics of light-harvesting complex II in a native membrane environment
- Source :
- Biophysical Journal, 120(2), 270-283, Biophysical Journal, 120(2), 270. Biophysical Society, Biophys J
- Publication Year :
- 2021
-
Abstract
- Photosynthetic light-harvesting complexes of higher plants, moss and green algae can undergo dynamic conformational transitions, which have been correlated to their ability to adapt to fluctuations in the light environment. Herein, we demonstrate the application of solid-state NMR spectroscopy on native, heterogeneous thylakoid membranes of Chlamydomonas reinhardtii (Cr) and on Cr Light-Harvesting Complex II (LHCII) in thylakoid lipid bilayers to detect LHCII conformational dynamics in its native membrane environment. We show that membrane-reconstituted LHCII contains selective sites that undergo fast, large-amplitude motions, including the phytol tails of two chlorophylls. Protein plasticity is also observed in the N-terminal stromal loop and in protein fragments facing the lumen, involving sites that stabilize the xanthophyll-cycle carotenoid violaxanthin and the two luteins. The results report on the intrinsic flexibility of LHCII pigment-protein complexes in a membrane environment, revealing putative sites for conformational switching. In thylakoid membranes, fast dynamics of protein and pigment sites is significantly reduced, which suggests that in their native organelle membranes, LHCII complexes are locked in specific conformational states.STATEMENT OF SIGNIFICANCEPhotosynthetic Light-Harvesting Complexes undergo dynamic conformational transitions that regulate the capacity of the light-harvesting antenna. We demonstrate the application of solid-state (ss)NMR spectroscopy to investigate the structural dynamics of LHCII, the most abundant LHC complex of plants and algae, in native membranes. Selective dynamic protein and pigment residues are identified that are putative sites for a conformational switch.
- Subjects :
- Chlorophyll
In situ
Light-Harvesting Protein Complexes
Biophysics
Chlamydomonas reinhardtii
010402 general chemistry
Photosynthesis
Thylakoids
01 natural sciences
03 medical and health sciences
chemistry.chemical_compound
0302 clinical medicine
Organelle
Lipid bilayer
030304 developmental biology
0303 health sciences
biology
Chemistry
Photosystem II Protein Complex
food and beverages
Articles
Nuclear magnetic resonance spectroscopy
biology.organism_classification
0104 chemical sciences
Membrane
Thylakoid
Helix
030217 neurology & neurosurgery
Violaxanthin
Subjects
Details
- Language :
- English
- ISSN :
- 00063495
- Database :
- OpenAIRE
- Journal :
- Biophysical Journal, 120(2), 270-283, Biophysical Journal, 120(2), 270. Biophysical Society, Biophys J
- Accession number :
- edsair.doi.dedup.....b46cdf24301d77d1a88eeabb11f7fb65