Members of this family are proteins/peptides, synthesized by one cell and secreted for insertion into the membrane of another cell where they form transmembrane pores. Pore-forming toxins (PFTs) are the most common bacterial cytotoxic proteins and are required for virulence in a large number of important pathogens.
Over 100 subgroups belong to the "Pore-forming Toxins" family, including amongst others:
- The α-Hemolysin Channel-forming Toxin (αHL) Family
- The Aerolysin Channel-forming Toxin (Aerolysin) Family
- The Botulinum and Tetanus Toxin (BTT) Family
- The Pertussis Toxin (PTX) Family
- The Crystal Protein (Cry) Family
Alpha-Hemolysin Background Information
Alpha-hemolysin, also called Alpha-toxin, is secreted by Staphylococcus aureus. It binds to the membrane of eukaryotic cells (particularly red blood cells, RBC and formes pores, resulting in hemolysis. This toxin causes cell death by binding with the outer membrane.
UniProt: P09616 (Staphylococcus aureus)
Alpha-hemolysin forms a homo-heptameric β-barrel in biological membranes.
The secreted monomeric species associates with animal cell membranes to form a 232 kDa homoheptameric transmembrane β-barrel pore that promotes cell death by allowing bilayer permeability to ions, water and small solutes, thereby promoting cell lysis. αHL forms a solvent-filled channel with a length of 100 Å.
Bilayer Recordings on the Orbit Product family
Reviews and Links
- Zhang et al.: Apoptosis induced by Staphylococcus aureus toxins (2017) Microbiological Research 205:19-24 doi: 10.1016/j.micres.2017.08.006
Transporter classification database:
Data and Applications