title: PSII-LHCII supercomplex organizations in photosynthetic membrane by coarse-grained simulation.
abstract: Green plant photosystem II (PSII) and light-harvesting complex II (LHCII) in the stacked grana regions of thylakoid membranes can self-organize into various PSII-LHCII supercomplexes with crystalline or fluid-like supramolecular structures to adjust themselves with external stimuli such as high/low light and temperatures, rendering tunable solar light absorption spectrum and photosynthesis efficiencies. However, the mechanisms controlling the PSII-LHCII supercomplex organizations remain elusive. In this work, we constructed a coarse-grained (CG) model of the thylakoid membrane including lipid molecules and a PSII-LHCII supercomplex considering association/dissociation of moderately bound-LHCIIs. The CG interaction between CG beads were constructed based on electron microscope (EM) experimental results, and we were able to simulate the PSII-LHCII supramolecular organization of a 500 × 500 nm(2) thylakoid membrane, which is compatible with experiments. Our CGMD simulations can successfully reproduce order structures of PSII-LHCII supercomplexes under various protein packing fractions, free-LHCII:PSII ratios, and temperatures, thereby providing insights into mechanisms leading to PSII-LHCII supercomplex organizations in photosynthetic membranes.
authors: Research Center for Applied Sciences, Academia Sinica , Taipei 11529, Taiwan.
authors: Cheng-Kuang
authors: CK
authors: Lee
authors: Chun-Wei
authors: CW
authors: Pao
authors: Berend
authors: B
authors: Smit
mesh_terms: D045342:Light-Harvesting Protein Complexes / Q000737:chemistry* / Q000378:metabolism; D008854:Microscopy, Electron; D056004:Molecular Dynamics Simulation; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000737:chemistry* / Q000378:metabolism; D020836:Protein Structure, Quaternary; D013696:Temperature; D020524:Thylakoids / Q000378:metabolism
chemical_list: D045342:Light-Harvesting Protein Complexes; D045332:Photosystem II Protein Complex