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Published on: August 28, 2018
Lipids in photosystem II: multifunctional cofactors
1Institut für Chemie/Max Volmer Laboratorium für Biophysikalische Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, D-10623 Berlin, Germany. janfkern@gmail.com
Journal of Photochemistry and Photobiology. B, Biology
|April 13, 2011
Summary
Lipids are essential cofactors in photosystem II (PSII) function, not just structural components. This study reveals their multifunctional roles in PSII operation and fine-tuning.
Area of Science:
- Biochemistry
- Structural Biology
- Photosynthesis Research
Background:
- Photosystem II (PSII) requires auxiliary molecules (cofactors) for functionality.
- Lipids were traditionally viewed as a hydrophobic matrix for membrane proteins.
- The specific roles of lipids in PSII fine-tuning and operation were not fully understood.
Purpose of the Study:
- To investigate the multifunctional roles of lipids as cofactors in photosystem II.
- To analyze the precise positioning and functional implications of lipids within PSII structure.
Main Methods:
- X-ray crystallography of cyanobacterial homodimeric PSII at 2.9 Å resolution.
- Detailed analysis of lipid binding sites and their interactions within the PSII complex.
Main Results:
- Identified 25 lipid molecules per monomer in the PSII structure.
- Bound lipids are crucial for PSII assembly and disassembly.
- Lipids facilitate plastoquinone exchange and may tune electron transfer.
- Lipids might function as an oxygen-outlet system from the lumen.
Conclusions:
- Lipids are multifunctional cofactors essential for photosystem II operation.
- The structural data provides insights into lipid-mediated regulation of PSII activity.
- Understanding lipid roles can inform strategies for optimizing photosynthetic efficiency.
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