%0 Journal Article
%T Characterization of SNARE Cleavage Products Generated by Formulated Botulinum Neurotoxin Type-A Drug Products
%A Terrence Hunt
%A David Rupp
%A Gary Shimizu
%A Karen Tam
%A Julia Weidler
%A Jack Xie
%J Toxins
%D 2010
%I MDPI AG
%R 10.3390/toxins2082198
%X The study evaluated substrate cleavage product(s) generated by three botulinum neurotoxin serotype A (BoNT/A) medicinal drug products utilizing a novel and highly specific, light-chain activity, high-performance liquid chromatography (LCA-HPLC) method. Samples were reacted with a commercially available BoNT/A fluorescent substrate derived from the SNAP-25 sequence. Reaction products were separated by reversed-phase HPLC. The method detected an atypical cleavage pattern by one of the formulated drug products. IncobotulinumtoxinA produced two cleavage fragments rather than the single fragment typically generated by BoNT/A. Identification confirmed the secondary cleavage at a position corresponding to SNAP-25 Arg198¨CAla199 (normal BoNT/A cleavage is Gln197¨CArg198). Arg198¨CAla199 is also the cleavage site for trypsin and serotype C toxin. Normal cleavage was observed for all other BoNT/A drug product samples, as well as 900-kD and 150-kD bulk toxin BoNT/A. The reason for this unexpected secondary cleavage pattern by one formulated BoNT/A drug product is unknown. Possible explanations include a contaminating protease and/or damage to the 150-kD type-A toxin causing nonspecific substrate recognition and subsequent cleavage uncharacteristic of type-A toxin. The BoNT/A drug products were also analyzed via the LCA-HPLC assay using a commercial BoNT/C fluorescent substrate derived from the syntaxin sequence. Cleavage of the serotype C substrate by incobotulinumtoxinA was also confirmed whilst neither of the other drug products cleaved the syntaxin substrate.
%K abotulinumtoxinA
%K botulinum toxin
%K BOTOX£¿
%K Dysport£¿
%K incobotulinumtoxinA
%K onabotulinumtoxin A
%K SNAP-25
%K SNARE
%K syntaxin
%K Xeomin£¿
%U http://www.mdpi.com/2072-6651/2/8/2198