Differential endopeptidase activity of different forms of type A botulinum neurotoxin: A unique relationship between the size of the substrate and activity of the enzyme

In this report, we demonstrate that SNAPtide as a commonly used substrate widely differ in reaction with BoNT/A complex, BoNT/A, and BoNT/A light chain. These findings have implications for assays used in detection, and in screening potential inhibitors.