Bal Ram Singh is in the Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, Dartmouth, Massachusetts 02747, USA. bsingh@umassd.edu
Crystal structures of type B botulinum neurotoxin, determined under conditions relevant to the extracellular binding and intracellular substrate cleavage steps of its toxic action, reveal that minimal structural changes occur upon binding a ganglioside or after substrate cleavage. The unique structure of this toxin provides information for developing preventive measures against botulism.
