Study reveals mechanisms underlying oxygen-tolerant energy conversion in a marine photosynthetic bacterium
Photosynthetic bacteria do not release oxygen during photosynthesis but can convert solar energy into chemical energy with remarkably high efficiency. They also utilize near-infrared light—wavelengths unused by plants—and thrive in diverse environments, including freshwater, seawater, and hot springs. Among these organisms, the marine purple nonsulfur bacterium Rhodovulum sulfidophilum is a model species notable for its strong tolerance to oxygen. However, the molecular mechanism by which its light-harvesting and energy-converting LH1-RC complex maintains highly efficient photosynthesis under oxic conditions remains unclear. Researchers at University of Tsukuba used cryo-electron microscopy to visualize the structure of the protein complex responsible for photosynthesis in Rhodovulum sulfidophilum. Their analysis uncovered a previously unrecognized membrane protein and revealed structural features that could explain how this organism achieves efficient energy conversion des...