Phys.org  April 5, 2023 Carboxysomes are proteinaceous bacterial microcompartments that sequester the key enzymes for carbon fixation in cyanobacteria and some proteobacteria. Despite their significance in carbon fixation and great bioengineering potentials, the structural understanding of native carboxysomes is currently limited to low-resolution studies. An international team of researchers (UK, Germany, Austria) has characterized a native α-carboxysome from a marine cyanobacterium by single-particle cryoelectron microscopy. They have determined the structure of its RuBisCO enzyme, and obtained low-resolution maps of its icosahedral shell, and its concentric interior organization. They proposed a complete atomic model of an intact carboxysome, providing insight into […]