Research Highlights

Prof. dr. Egbert Boekema

Structure of photosynthetic complexes by electron microscopy

Photosynthesis by plants, algae and cyanobacteria is the energy conversion process where photons from sunlight are converted into chemically fixed energy. The main protein complexes involved are Photosystem I (PSI) and Photosystem II (PSII) that work in concert to carry out the light conversion steps leading to ATP and NADPH production in successive steps. Single particle cryo-electron microscopy is very useful to study the structure of complex membrane proteins at the level of medium – high resolution. The Boekema group focuses on the structure of the peripheral antenna of Photosystems I and II and has obtained significant results, including the concept of supercomplex formation of PSI and PSII with other components of the light reactions of photosynthesis. A novel supercomplex between PSI and light-harvesting complex II has been described^a and another relevant discovery concerns the function of the PSII antenna^b. Recent advances in cryo-EM allowed us to get 3D models at much higher resolution such as from the novel cyanobacterial tetrameric PSI structure (see figure)^c. Additional research, in collaboration with GBB or other groups, concerns utmost relevant bacterial complexes such as CRISPR^d,e.

^aPlant J (2014); ^bPlant Cell (2014); ^cBBA Bioenerg (2016); ^dNature Cell Biol (2010); ^ePNAS USA (2014)