Fig. 1.

Tetanus toxin. Tetanus neurotoxin is a 150 kDa tripartite toxin with a 50 kDa light chain which exhibits zinc endopeptidase activity and a 100 kDa heavy chain (H). The Hc domain can be further derivatised into two topologically distinct sub-domains termed HcC and HcN denoting C and N-terminal portions respectively. The panel of scFvs used in this study specifically binds the N-terminal sub-domain (clones N1 through N5), C-terminal sub-domain (C1 through C5) or the whole Hc fragment only (J1 through J5).