Pore-forming toxins (PFTs) attracted the interest of structural biologists and microbiologists for decades due to its ability to act as soluble proteins and transmembrane complexes. PFTs are secreted as water soluble monomers, thereafter connect to the membrane of target cells. After that, they gather into circular oligomers, which enable its insertion into membrane via conformational changes in its composition resulting pore forming and cell death. Cryo-electron microscopy revealed a protein fold composed of two concentric beta barrels tightly linked by hydrophobic interactions. Aerolysin is a heptamer which seven molecules together form a barrel composed of 14 strands.

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