1.C.69 The Clostridium perfringens Beta-2 Toxin (Beta-2) Family

Clostridium perfringens beta-2 toxin (265 aas) forms pores in animal cells. The pore is fairly non-specific: K+, Ca2+, Na+ and Cl- fluxes were measured following treatment of HL60 cells with the toxin (Nagahama et al., 2003). The toxin forms oligomeric complexes of about 191 and 228 kDa in lipid rafts.

A 120 residue region of the ε-toxin of Clostridium perfringens (TC #1.C.5.1.1) shows significant sequence similarity to the pesticidal crystal protein Cry15Aa (insecticidal δ-endotoxin CryXVA(a)), and the first 77 residues of the epsilon toxin show sequence similarity with the first 82 residues of the beta-2 toxin of C. perfringens (TC #1.C.69). Cry15Aa is not demonstrably homologous to members of the channel-forming δ-endotoxin insecticidal crystal protein (ICP) family (TC #1.C.2).

The reactions catalyzed by beta toxin are:

ions (in) ions (out)



Nagahama, M. S. Hayashi, S. Morimitsu, and J. Sakurai. (2003). Biological activities and pore formation of Clostridium perfringens beta toxin in HL 60 cells. J. Biol. Chem. 278: 36934-36941.


TC#NameOrganismal TypeExample
1.C.69.1.1Beta-2 toxinGram-positive bacteriaBeta-2 toxin of Clostridium perfringens (BAB62455)

Beta2-toxin of 265 aas, Cpb2

Cpb2 of Clostridium perfringens


Uncharacterized protein of 249 aas

UP of Bacillus cereus