Across bacteria. protein-based organelles called bacterial microcompartments (BMCs) encapsulate key enzymes to regulate their activities. The model BMC is the carboxysome that encapsulates enzymes for CO2 fixation to increase efficiency and is found in many autotrophic bacteria. such as cyanobacteria. https://www.roneverhart.com/Carin-Shard-East-Non-Ladder/