The tetanus toxin protein has a molecular weight of 150 kDa. It is translated from the tetX gene as one protein which is subsequently cleaved into two parts: a 100 kDa heavy or B-chain and a 50 kDa light or A-chain. The chains are connected by a disulfide bond. * The B-chain binds to disialogangliosides (GD2 and GD1b) on the neuronal membrane and contains a translocation domain which aids the movement of the protein across that membrane and into the neuron. * The A-chain, an M27-family zinc endopeptidase, attacks the vesicle-associated membrane protein (VAMP). The TetX gene encoding this protein is located on the PE88 plasmid. Several structures of the binding domain and the peptidase domain have been solved by X-ray crystallography and deposited in the PDB. A summary of these structures is available using the UniPDB application at PDBe, for example or .
Tetanospasmin
Immunoevasin
Pentostatin
Endrin
Anordrin
Thrombin
Fibrinolysin
Cathelicidin