Characterization of enzyme scaffolding inside the alpha-carboxysome by cryo-electron tomography.

Abstract

Roughly 20% of bacteria employ bacterial microcompartments (BMCs) to sequester enzymatic processes. In these structures, a cargo of enzymes and accessory proteins is encased within a semi-permeable protein shell that permits passage of substrates and products but restricts movement of intermediates. In addition to their importance as a component of many bacterial species’ metabolisms, BMCs have become a target of protein engineering due to their potential for enclosing cargos of choice for alternative pharmacological and biotechnological applications. The shells can be reassembled from purified proteins, and the full operons can be functionally expressed outside their native prokaryotes.