Under these circumstances, a group of Mie University, Ibaraki University, Okinawa Institute of Science and Technology Graduate University and others used a cryo-electron microscope to create a three-dimensional "core light collection complex" of Rhodospirillum rubrum (R. rubrum), a type of photosynthetic bacterium. Succeeded in visualizing.A photosynthetic complex is a complex membrane protein that allows photosynthetic bacteria to collect light energy and convert it from light to electrons for transmission.So far, the structure of another core light-harvesting complex that stabilizes in the presence of Ca2 + (calcium ion) has been clarified, but this complex has a stable interaction even in the absence of Ca2 +. It turned out that. This is the first time that the mechanism of a complex that is independent of Ca2 + has been clarified.

　Furthermore, by clarifying the detailed three-dimensional structure, the binding state of "rhodoquinone", which functions as an electron carrier for energy conversion, was also visualized.This suggested a model of the inflow and outflow pathways of quinones, and was able to clarify the pathway of electron transfer via quinones from the capture of light.

　This result is expected to be a hint that contributes to the development of diverse and efficient artificial use of solar energy.In addition, photosynthetic bacteria are being utilized in agriculture, and rhodoquinone is also attracting attention as an anthelmintic drug target, so it may contribute to the development of safe anthelmintic drugs.

Paper information:[Biochemistry] Cryo-EM Structure of the Photosynthetic LH1-RC Complex from Rhodospirillum rubrum