Fig. 2: Transmission electron photomicrographs (magnification 71,000×) showing the highly symmetrical bacterial microcompartments (BMCs)/carboxysome-like structures.

a Red arrows indicate carboxysome-like structures in the cellular cytoplasm of Carbonactinospora thermoautotrophica StC; b a close view of a carboxysome- like structure; and c The Fast Fourier Transform (FFT) image of the carboxysome-like structure, which is a mathematical representation of the spatial frequencies of the image25, showing that the StC carboxysome-like structure has a periodic organization with a well-ordered and highly symmetrical pattern.