Molecular Dynamics of Photosystem II Embedded in the Thylakoid Membranevan Eerden, F. J., van den Berg, T., Frederix, P. W. J. M., de Jong, D. H., Periole, X. & Marrink, S. J., 21-Apr-2017, In : Journal of Physical Chemistry B.. 121, 15, p. 3237–3249 jpcb.6b06865.
Research output: Contribution to journal › Article › Academic › peer-review
Photosystem II (PSII) is one of the key protein complexes in photosynthesis. We introduce a coarse grained model of PSII and present the analysis of 60 µs molecular dynamics simulations of PSII in both monomeric and dimeric form, embedded in a thylakoid membrane model that reflects its native lipid composition. We describe in detail the setup of the protein complex and the many natural cofactors, and characterize their mobility. Overall we find that the protein subunits and cofactors are more flexible towards the periphery of the complex, as well as near the PLQ exchange cavity and at the dimer interface. Of all cofactors, β-carotenes show the highest mobility. Some of the β-carotenes diffuse in and out of the protein complex via the thylakoid membrane. In contrast to the PSII dimer, the monomeric form adopts a tilted conformation in the membrane, with strong interactions between the soluble PsbO subunit and the glycolipid headgroups. Interestingly, the tilted conformation causes buckling of the membrane. Together, our results provide an unprecedented view of PSII dynamics on a microsecond time scale. Our data may be used as basis for the interpretation of experimental data as well as for theoretical models describing exciton energy transfer.
|Journal||Journal of Physical Chemistry B.|
|Publication status||Published - 21-Apr-2017|