The C terminus of the catalytic domain of type A botulinum neurotoxin may facilitate product release from the active site

Abstract

Background: The function of C terminus of botulinum neurotoxin catalytic domain is unknown. Results: Synthetic C-terminal peptides competitively inhibited but at stoichiometric concentrations stimulated serotype A proteolytic activity. Conclusion: C terminus interacts with the active site and may function by removing a product. Significance: The inhibition and product removal appear to be a unique feature of typeAbotulinum neurotoxin among catalytic proteins. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.