Structural analysis of the catalytic and binding sites of Clostridium botulinum neurotoxin B

Clostridium botulinum neurotoxins are among the most potent toxins to human s. The crystal structures of intact C. botulinum neurotoxin type B (BoNT/B) and its complex with sialyllactose, determined at 1.8 and 2.6 Angstrom res olution, respectively, provide insight into its catalytic and binding sites . The position of the belt region in BoNT/B is different from that in BoNT/ A; this observation presents interesting possibilities for designing specif ic inhibitors that could be used to block the activity of this neurotoxin. The structures of BoNT/B and its complex with sialyllactose provide a detai led description of the active site and a model for interactions between the toxin and its cell surface receptor. The latter may provide valuable infor mation for recombinant vaccine development.