TABLE 1.

Bacterial host and substrate targets of large clostridial toxins

ToxinOrganismSize (kDa)Intracellular targets
TcdAC. difficile308Rho, Rac, Cdc42
TcdBC. difficile270Rho, Rac, Cdc42
TcsHC. sordellii300Rho, Rac, Cdc42
TcsLC. sordellii270Ras, Rac, Rap, Ral, (Cdc42)b
TcnαC. novyi250Rho, Rac, Cdc42
TcdB-1470aC. difficile 1470270Ras, Rac, Rap, Ral, Cdc42
  • a TcdB-1470 is a hybrid between the TcdB cell entry domains and the TcsL enzymatic domain.

  • b Glucosylation of Cdc42 is strain specific in C. sordellii.