<p>Aerolysin is a cytolytic toxin exported by the Gram-negative Aeromonasbacteria. The mature toxin binds to eukaryotic cells and aggregates to formholes (approximately 3 nm in diameter) leading to the destruction of themembrane permeability barrier and osmotic lysis. <taxon tax_id="1280">Staphylococcus aureus</taxon> also exports a cytotoxin, alpha-toxin, whose biological activity is similar to that of aerolysin. The sequences of both toxins are not similar except for a stretch of ten residues rather well conserved.</p>