Detailed Analysis Of Photosystem/Light-Harvesting Complex

Photosynthesis produces oxygen and carbohydrates from water and carbon dioxide efficiently, giving living things oxygen to breathe and food to eat at the same time. The detailed way in which it accomplishes this feat is something scientists would like to better understand, in part to perhaps mimic photosynthesis. Tingyun Kuang, Jian-Ren Shen, and coworkers at the Chinese Academy of Sciences, in Beijing, and Okayama University, in Japan, have now moved that goal one step closer to realization by determining the first atomic-resolution crystal structure of the pea plant’s photosystem I/light-harvesting complex I, a huge photosynthetic protein supercomplex found in higher plants (Science 2015, DOI: 10.1126/science.aab0214). One view of the structure (shown) makes it look like a pointy-headed jack-o’-lantern, in which subunits of photosystem I surround the eyes and a series of light-harvesting complex I proteins sit below the mouth. The structure, which reveals specific interactions between the supercomplex’s components, including numerous pigments and other cofactors, could lead to a more in-depth fundamental understanding of the highly efficient energy transfer and photoprotection mechanisms of plant photosynthesis.