Clostridium neurotoxin, receptor-binding C-terminal <p>The Clostridium neurotoxin family is composed of tetanus neurotoxins and seven serotypes of botulinum neurotoxin. The structure of the botulinum neurotoxin reveals a four domain protein. The N-terminal catalytic domain (<db_xref db="INTERPRO" dbkey="IPR000395"/>), the central translocation domains and two receptor-binding domains [<cite idref="PUB00016466"/>]. This domain is the C-terminal receptor-binding domain, which adopts a modified beta-trefoil fold with a six stranded beta-barrel and a beta-hairpin triplet capping the domain [<cite idref="PUB00016466"/>]. The first step in the intoxication process is a binding event between this domain and the pre-synaptic nerve ending [<cite idref="PUB00016466"/>]. </p>