Structure of photosystem I complex of primordial cyanobacterium

April 14, 2022

A key to unravelling the evolution of photosynthetic organisms

A research group of Okayama University and the RIKEN SPring-8 Center, in collaboration with Kobe University and the RIKEN CSRS, successfully determined the structure of a photosystem I (PSI) trimer from a primordial cyanobacterium Gloeobacter using cryo-electron microscopy. The researchers found that the PSI trimer in this bacterium has amino acid sequences and pigment molecule arrangement in specific subunits significantly different from those in other cyanobacteria. In particular, Gloeobacter’s PSI lacked some chlorophylls. These features of PSI could be used as indicators of the evolution of photosynthetic organisms.

Original article
eLife doi:10.7554/eLife.73990
K. Kato, T. Hamaguchi, R. Nagao, K. Kawakami, Y. Ueno, T. Suzuki, H. Uchida, A. Murakami, Y. Nakajima, M. Yokono, S. Akimoto, N. Dohmae, K. Yonekura, J.-R. Shen,
"Structural basis for the absence of low-energy chlorophylls in a photosystem I trimer from Gloeobacter violaceus".
Naoshi Dohmae
Unit Leader
Biomolecular Characterization Unit