Photosynthesis involves a protein 'piston'

(Osaka University) The photosystem I (PSI)-ferrodoxin (Fd) complex is important in electron transfer during photosynthesis, through which plants convert sunlight, carbon dioxide, and water into complex chemicals and oxygen. An Osaka University-led international collaboration recently crystallized the PSI-Fd complex for the first time. They found that the PSI-Fd complex contained Fd with weak and strong binding states and that Fd binding caused the PSI subunits to reorganize into a structure that facilitated rapid electron transfer.